In xen_memory_setup() pages that occur in gaps in the memory map are
released back to Xen. This reduces the domain's current page count in
the hypervisor. The Xen balloon driver does not correctly decrease
its initial current_pages count to reflect this. If 'delta' pages are
released and the target is adjusted the resulting reservation is
always 'delta' less than the requested target.
This affects dom0 if the initial allocation of pages overlaps the PCI
memory region but won't affect most domU guests that have been setup
with pseudo-physical memory maps that don't have gaps.
Fix this by accouting for the released pages when starting the balloon
driver.
If the domain's targets are managed by xapi, the domain may eventually
run out of memory and die because xapi currently gets its target
calculations wrong and whenever it is restarted it always reduces the
target by 'delta'.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Xen PV on HVM guests require PCI support because they need the
xen-platform-pci driver in order to initialize xenbus.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If we want to use granted pages for AIO, changing the mappings of a user
vma and the corresponding p2m is not enough, we also need to update the
kernel mappings accordingly.
Currently this is only needed for pages that are created for user usages
through /dev/xen/gntdev. As in, pages that have been in use by the
kernel and use the P2M will not need this special mapping.
However there are no guarantees that in the future the kernel won't
start accessing pages through the 1:1 even for internal usage.
In order to avoid the complexity of dealing with highmem, we allocated
the pages lowmem.
We issue a HYPERVISOR_grant_table_op right away in
m2p_add_override and we remove the mappings using another
HYPERVISOR_grant_table_op in m2p_remove_override.
Considering that m2p_add_override and m2p_remove_override are called
once per page we use multicalls and hypercall batching.
Use the kmap_op pointer directly as argument to do the mapping as it is
guaranteed to be present up until the unmapping is done.
Before issuing any unmapping multicalls, we need to make sure that the
mapping has already being done, because we need the kmap->handle to be
set correctly.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
[v1: Removed GRANT_FRAME_BIT usage]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We use the page->private field and hence should use the proper
macros and set proper bits. Also WARN_ON in case somebody
tries to overwrite our data.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We dropped a lot of the MMU debugfs in favour of using
tracing API - but there is one which just provides
mostly static information that was made invisible by this change.
Bring it back.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'stable/bug.fixes' of git://oss.oracle.com/git/kwilk/xen:
xen/i386: follow-up to "replace order-based range checking of M2P table by linear one"
xen/irq: Alter the locking to use a mutex instead of a spinlock.
xen/e820: if there is no dom0_mem=, don't tweak extra_pages.
xen: disable PV spinlocks on HVM
The numbers obtained from the hypervisor really can't ever lead to an
overflow here, only the original calculation going through the order
of the range could have. This avoids the (as Jeremy points outs)
somewhat ugly NULL-based calculation here.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The patch "xen: use maximum reservation to limit amount of usable RAM"
(d312ae878b) breaks machines that
do not use 'dom0_mem=' argument with:
reserve RAM buffer: 000000133f2e2000 - 000000133fffffff
(XEN) mm.c:4976:d0 Global bit is set to kernel page fffff8117e
(XEN) domain_crash_sync called from entry.S
(XEN) Domain 0 (vcpu#0) crashed on cpu#0:
...
The reason being that the last E820 entry is created using the
'extra_pages' (which is based on how many pages have been freed).
The mentioned git commit sets the initial value of 'extra_pages'
using a hypercall which returns the number of pages (if dom0_mem
has been used) or -1 otherwise. If the later we return with
MAX_DOMAIN_PAGES as basis for calculation:
return min(max_pages, MAX_DOMAIN_PAGES);
and use it:
extra_limit = xen_get_max_pages();
if (extra_limit >= max_pfn)
extra_pages = extra_limit - max_pfn;
else
extra_pages = 0;
which means we end up with extra_pages = 128GB in PFNs (33554432)
- 8GB in PFNs (2097152, on this specific box, can be larger or smaller),
and then we add that value to the E820 making it:
Xen: 00000000ff000000 - 0000000100000000 (reserved)
Xen: 0000000100000000 - 000000133f2e2000 (usable)
which is clearly wrong. It should look as so:
Xen: 00000000ff000000 - 0000000100000000 (reserved)
Xen: 0000000100000000 - 000000027fbda000 (usable)
Naturally this problem does not present itself if dom0_mem=max:X
is used.
CC: stable@kernel.org
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
PV spinlocks cannot possibly work with the current code because they are
enabled after pvops patching has already been done, and because PV
spinlocks use a different data structure than native spinlocks so we
cannot switch between them dynamically. A spinlock that has been taken
once by the native code (__ticket_spin_lock) cannot be taken by
__xen_spin_lock even after it has been released.
Reported-and-Tested-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'stable/bug.fixes' of git://oss.oracle.com/git/kwilk/xen:
xen/smp: Warn user why they keel over - nosmp or noapic and what to use instead.
xen: x86_32: do not enable iterrupts when returning from exception in interrupt context
xen: use maximum reservation to limit amount of usable RAM
We have hit a couple of customer bugs where they would like to
use those parameters to run an UP kernel - but both of those
options turn of important sources of interrupt information so
we end up not being able to boot. The correct way is to
pass in 'dom0_max_vcpus=1' on the Xen hypervisor line and
the kernel will patch itself to be a UP kernel.
Fixes bug: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=637308
CC: stable@kernel.org
Acked-by: Ian Campbell <Ian.Campbell@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If vmalloc page_fault happens inside of interrupt handler with interrupts
disabled then on exit path from exception handler when there is no pending
interrupts, the following code (arch/x86/xen/xen-asm_32.S:112):
cmpw $0x0001, XEN_vcpu_info_pending(%eax)
sete XEN_vcpu_info_mask(%eax)
will enable interrupts even if they has been previously disabled according to
eflags from the bounce frame (arch/x86/xen/xen-asm_32.S:99)
testb $X86_EFLAGS_IF>>8, 8+1+ESP_OFFSET(%esp)
setz XEN_vcpu_info_mask(%eax)
Solution is in setting XEN_vcpu_info_mask only when it should be set
according to
cmpw $0x0001, XEN_vcpu_info_pending(%eax)
but not clearing it if there isn't any pending events.
Reproducer for bug is attached to RHBZ 707552
CC: stable@kernel.org
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Use the domain's maximum reservation to limit the amount of extra RAM
for the memory balloon. This reduces the size of the pages tables and
the amount of reserved low memory (which defaults to about 1/32 of the
total RAM).
On a system with 8 GiB of RAM with the domain limited to 1 GiB the
kernel reports:
Before:
Memory: 627792k/4472000k available
After:
Memory: 549740k/11132224k available
A increase of about 76 MiB (~1.5% of the unused 7 GiB). The reserved
low memory is also reduced from 253 MiB to 32 MiB. The total
additional usable RAM is 329 MiB.
For dom0, this requires at patch to Xen ('x86: use 'dom0_mem' to limit
the number of pages for dom0') (c/s 23790)
CC: stable@kernel.org
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The tracing code used sched_clock() to get tracing timestamps, which
ends up calling xen_clocksource_read(). xen_clocksource_read() must
disable preemption, but if preemption tracing is enabled, this results
in infinite recursion.
I've only noticed this when boot-time tracing tests are enabled, but it
seems like a generic bug. It looks like it would also affect
kvm_clocksource_read().
Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
* 'stable/bug.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/tracing: Fix tracing config option properly
xen: Do not enable PV IPIs when vector callback not present
xen/x86: replace order-based range checking of M2P table by linear one
xen: xen-selfballoon.c needs more header files
Steven Rostedt says we should use CONFIG_EVENT_TRACING.
Cc:Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Fix regression for HVM case on older (<4.1.1) hypervisors caused by
commit 99bbb3a84a
Author: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Date: Thu Dec 2 17:55:10 2010 +0000
xen: PV on HVM: support PV spinlocks and IPIs
This change replaced the SMP operations with event based handlers without
taking into account that this only works when the hypervisor supports
callback vectors. This causes unexplainable hangs early on boot for
HVM guests with more than one CPU.
BugLink: http://bugs.launchpad.net/bugs/791850
CC: stable@kernel.org
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-and-Reported-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The order-based approach is not only less efficient (requiring a shift
and a compare, typical generated code looking like this
mov eax, [machine_to_phys_order]
mov ecx, eax
shr ebx, cl
test ebx, ebx
jnz ...
whereas a direct check requires just a compare, like in
cmp ebx, [machine_to_phys_nr]
jae ...
), but also slightly dangerous in the 32-on-64 case - the element
address calculation can wrap if the next power of two boundary is
sufficiently far away from the actual upper limit of the table, and
hence can result in user space addresses being accessed (with it being
unknown what may actually be mapped there).
Additionally, the elimination of the mistaken use of fls() here (should
have been __fls()) fixes a latent issue on x86-64 that would trigger
if the code was run on a system with memory extending beyond the 44-bit
boundary.
CC: stable@kernel.org
Signed-off-by: Jan Beulich <jbeulich@novell.com>
[v1: Based on Jeremy's feedback]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-tip:
x86-64: Rework vsyscall emulation and add vsyscall= parameter
x86-64: Wire up getcpu syscall
x86: Remove unnecessary compile flag tweaks for vsyscall code
x86-64: Add vsyscall:emulate_vsyscall trace event
x86-64: Add user_64bit_mode paravirt op
x86-64, xen: Enable the vvar mapping
x86-64: Work around gold bug 13023
x86-64: Move the "user" vsyscall segment out of the data segment.
x86-64: Pad vDSO to a page boundary
We don' use it anymore and there are more false positives.
This reverts commit fc25151d9a.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'stable/bug.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/trace: Fix compile error when CONFIG_XEN_PRIVILEGED_GUEST is not set
xen: Fix misleading WARN message at xen_release_chunk
xen: Fix printk() format in xen/setup.c
xen/tracing: it looks like we wanted CONFIG_FTRACE
xen/self-balloon: Add dependency on tmem.
xen/balloon: Fix compile errors - missing header files.
xen/grant: Fix compile warning.
xen/pciback: remove duplicated #include
with CONFIG_XEN and CONFIG_FTRACE set we get this:
arch/x86/xen/trace.c:22: error: ‘__HYPERVISOR_console_io’ undeclared here (not in a function)
arch/x86/xen/trace.c:22: error: array index in initializer not of integer type
arch/x86/xen/trace.c:22: error: (near initialization for ‘xen_hypercall_names’)
arch/x86/xen/trace.c:23: error: ‘__HYPERVISOR_physdev_op_compat’ undeclared here (not in a function)
Issue was that the definitions of __HYPERVISOR were not pulled
if CONFIG_XEN_PRIVILEGED_GUEST was not set.
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Three places in the kernel assume that the only long mode CPL 3
selector is __USER_CS. This is not true on Xen -- Xen's sysretq
changes cs to the magic value 0xe033.
Two of the places are corner cases, but as of "x86-64: Improve
vsyscall emulation CS and RIP handling"
(c9712944b2), vsyscalls will segfault
if called with Xen's extra CS selector. This causes a panic when
older init builds die.
It seems impossible to make Xen use __USER_CS reliably without
taking a performance hit on every system call, so this fixes the
tests instead with a new paravirt op. It's a little ugly because
ptrace.h can't include paravirt.h.
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/f4fcb3947340d9e96ce1054a432f183f9da9db83.1312378163.git.luto@mit.edu
Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Xen needs to handle VVAR_PAGE, introduced in git commit:
9fd67b4ed0
x86-64: Give vvars their own page
Otherwise we die during bootup with a message like:
(XEN) mm.c:940:d10 Error getting mfn 1888 (pfn 1e3e48) from L1 entry
8000000001888465 for l1e_owner=10, pg_owner=10
(XEN) mm.c:5049:d10 ptwr_emulate: could not get_page_from_l1e()
[ 0.000000] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 0.000000] IP: [<ffffffff8103a930>] xen_set_pte+0x20/0xe0
Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/4659478ed2f3480938f96491c2ecbe2b2e113a23.1312378163.git.luto@mit.edu
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
WARN message should not complain
"Failed to release memory %lx-%lx err=%d\n"
^^^^^^^
about range when it fails to release just one page,
instead it should say what pfn is not freed.
In addition line:
printk(KERN_INFO "xen_release_chunk: looking at area pfn %lx-%lx: "
...
printk(KERN_CONT "%lu pages freed\n", len);
will be broken if WARN in between this line is fired. So fix it
by using a single printk for this.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Use correct format specifier for unsigned long.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Apparently we wanted CONFIG_FTRACE rather the CONFIG_FUNCTION_TRACER.
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6:
cpuidle: stop depending on pm_idle
x86 idle: move mwait_idle_with_hints() to where it is used
cpuidle: replace xen access to x86 pm_idle and default_idle
cpuidle: create bootparam "cpuidle.off=1"
mrst_pmu: driver for Intel Moorestown Power Management Unit
When a Xen Dom0 kernel boots on a hypervisor, it gets access
to the raw-hardware ACPI tables. While it parses the idle tables
for the hypervisor's beneift, it uses HLT for its own idle.
Rather than have xen scribble on pm_idle and access default_idle,
have it simply disable_cpuidle() so acpi_idle will not load and
architecture default HLT will be used.
cc: xen-devel@lists.xensource.com
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
When CONFIG_FUNCTION_TRACER is disabled, compilation fails as follows:
CC arch/x86/xen/setup.o
In file included from arch/x86/include/asm/xen/hypercall.h:42,
from arch/x86/xen/setup.c:19:
include/trace/events/xen.h:31: warning: 'struct multicall_entry' declared inside parameter list
include/trace/events/xen.h:31: warning: its scope is only this definition or declaration, which is probably not what you want
include/trace/events/xen.h:31: warning: 'struct multicall_entry' declared inside parameter list
include/trace/events/xen.h:31: warning: 'struct multicall_entry' declared inside parameter list
include/trace/events/xen.h:31: warning: 'struct multicall_entry' declared inside parameter list
[...]
arch/x86/xen/trace.c:5: error: '__HYPERVISOR_set_trap_table' undeclared here (not in a function)
arch/x86/xen/trace.c:5: error: array index in initializer not of integer type
arch/x86/xen/trace.c:5: error: (near initialization for 'xen_hypercall_names')
arch/x86/xen/trace.c:6: error: '__HYPERVISOR_mmu_update' undeclared here (not in a function)
arch/x86/xen/trace.c:6: error: array index in initializer not of integer type
arch/x86/xen/trace.c:6: error: (near initialization for 'xen_hypercall_names')
Fix this by making sure struct multicall_entry has a declaration in
scope at all times, and don't bother compiling xen/trace.c when tracing
is disabled.
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
* 'stable/drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pciback: Have 'passthrough' option instead of XEN_PCIDEV_BACKEND_PASS and XEN_PCIDEV_BACKEND_VPCI
xen/pciback: Remove the DEBUG option.
xen/pciback: Drop two backends, squash and cleanup some code.
xen/pciback: Print out the MSI/MSI-X (PIRQ) values
xen/pciback: Don't setup an fake IRQ handler for SR-IOV devices.
xen: rename pciback module to xen-pciback.
xen/pciback: Fine-grain the spinlocks and fix BUG: scheduling while atomic cases.
xen/pciback: Allocate IRQ handler for device that is shared with guest.
xen/pciback: Disable MSI/MSI-X when reseting a device
xen/pciback: guest SR-IOV support for PV guest
xen/pciback: Register the owner (domain) of the PCI device.
xen/pciback: Cleanup the driver based on checkpatch warnings and errors.
xen/pciback: xen pci backend driver.
xen: tmem: self-ballooning and frontswap-selfshrinking
xen: Add module alias to autoload backend drivers
xen: Populate xenbus device attributes
xen: Add __attribute__((format(printf... where appropriate
xen: prepare tmem shim to handle frontswap
xen: allow enable use of VGA console on dom0
Singleton calls seem to end up being pretty common, so just
directly call the hypercall rather than going via multicall.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
It's useful - and probably should be a config - but its very heavyweight,
especially with the tracing stuff to help sort out problems.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Make sure the fastpath code is inlined. Batch the page permission change
and the pin/unpin, and make sure that it can be batched with any
adjacent set_pte/pmd/etc operations.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Other than sanity check and debug message, the x86 specific version of
memblock reserve/free functions are simple wrappers around the generic
versions - memblock_reserve/free().
This patch adds debug messages with caller identification to the
generic versions and replaces x86 specific ones and kills them.
arch/x86/include/asm/memblock.h and arch/x86/mm/memblock.c are empty
after this change and removed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310462166-31469-14-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Removing __init from check_platform_magic since it is called by
xen_unplug_emulated_devices in non-init contexts (It probably gets inlined
because of -finline-functions-called-once, removing __init is more to avoid
mismatch being reported).
Signed-off-by: Raghavendra D Prabhu <rprabhu@wnohang.net>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Simple enough - we use an extern defined symbol which is not
defined when CONFIG_SMP is not defined. This fixes the linker
dying.
CC: stable@kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The earlier attempts (24bdb0b62c)
at fixing this problem caused other problems to surface (PV guests
with no PCI passthrough would have SWIOTLB turned on - which meant
64MB of precious contingous DMA32 memory being eaten up per guest).
The problem was: "on xen we add an extra memory region at the end of
the e820, and on this particular machine this extra memory region
would start below 4g and cross over the 4g boundary:
[0xfee01000-0x192655000)
Unfortunately e820_end_of_low_ram_pfn does not expect an
e820 layout like that so it returns 4g, therefore initial_memory_mapping
will map [0 - 0x100000000), that is a memory range that includes some
reserved memory regions."
The memory range was the IOAPIC regions, and with the 1-1 mapping
turned on, it would map them as RAM, not as MMIO regions. This caused
the hypervisor to complain. Fortunately this is experienced only under
the initial domain so we guard for it.
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
.. As it won't actually power off the machine.
Reported-by: Sven Köhler <sven.koehler@gmail.com>
Tested-by: Sven Köhler <sven.koehler@gmail.com>
Signed-off-by: Tom Goetz <tom.goetz@virtualcomputer.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The MAXSMP config option requires CPUMASK_OFFSTACK, which in turn
requires we init the memory for the maps while we bring up the cpus.
MAXSMP also increases NR_CPUS to 4096. This increase in size exposed an
issue in the argument construction for multicalls from
xen_flush_tlb_others. The args should only need space for the actual
number of cpus.
Also in 2.6.39 it exposes a bootup problem.
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffff8157a1d3>] set_cpu_sibling_map+0x123/0x30d
...
Call Trace:
[<ffffffff81039a3f>] ? xen_restore_fl_direct_reloc+0x4/0x4
[<ffffffff819dc4db>] xen_smp_prepare_cpus+0x36/0x135
..
CC: stable@kernel.org
Signed-off-by: Andrew Jones <drjones@redhat.com>
[v2: Updated to compile on 3.0]
[v3: Updated to compile when CONFIG_SMP is not defined]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We only need to set max_pfn_mapped to the last pfn mapped on x86_64 to
make sure that cleanup_highmap doesn't remove important mappings at
_end.
We don't need to do this on x86_32 because cleanup_highmap is not called
on x86_32. Besides lowering max_pfn_mapped on x86_32 has the unwanted
side effect of limiting the amount of memory available for the 1:1
kernel pagetable allocation.
This patch reverts the x86_32 part of the original patch.
CC: stable@kernel.org
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Get the information about the VGA console hardware from Xen, and put
it into the form the bootloader normally generates, so that the rest
of the kernel can deal with VGA as usual.
[ Impact: make VGA console work in dom0 ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
[v1: Rebased on 2.6.39]
[v2: Removed incorrect comments and fixed compile warnings]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
b->args[] has MC_ARGS elements, so the comparison here should be
">=" instead of ">". Otherwise we read past the end of the array
one space.
CC: stable@kernel.org
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
* 'upstream/tidy-xen-mmu-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen: fix compile without CONFIG_XEN_DEBUG_FS
Use arbitrary_virt_to_machine() to deal with ioremapped pud updates.
Use arbitrary_virt_to_machine() to deal with ioremapped pmd updates.
xen/mmu: remove all ad-hoc stats stuff
xen: use normal virt_to_machine for ptes
xen: make a pile of mmu pvop functions static
vmalloc: remove vmalloc_sync_all() from alloc_vm_area()
xen: condense everything onto xen_set_pte
xen: use mmu_update for xen_set_pte_at()
xen: drop all the special iomap pte paths.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits)
b43: fix comment typo reqest -> request
Haavard Skinnemoen has left Atmel
cris: typo in mach-fs Makefile
Kconfig: fix copy/paste-ism for dell-wmi-aio driver
doc: timers-howto: fix a typo ("unsgined")
perf: Only include annotate.h once in tools/perf/util/ui/browsers/annotate.c
md, raid5: Fix spelling error in comment ('Ofcourse' --> 'Of course').
treewide: fix a few typos in comments
regulator: change debug statement be consistent with the style of the rest
Revert "arm: mach-u300/gpio: Fix mem_region resource size miscalculations"
audit: acquire creds selectively to reduce atomic op overhead
rtlwifi: don't touch with treewide double semicolon removal
treewide: cleanup continuations and remove logging message whitespace
ath9k_hw: don't touch with treewide double semicolon removal
include/linux/leds-regulator.h: fix syntax in example code
tty: fix typo in descripton of tty_termios_encode_baud_rate
xtensa: remove obsolete BKL kernel option from defconfig
m68k: fix comment typo 'occcured'
arch:Kconfig.locks Remove unused config option.
treewide: remove extra semicolons
...
We no longer support HIGHPTE allocations, so ptes should always be
within the kernel's direct map, and don't need pagetable walks
to convert to machine addresses.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
xen_set_pte_at and xen_clear_pte are essentially identical to
xen_set_pte, so just make them all common.
When batched set_pte and pte_clear are the same, but the unbatch operation
must be different: they need to update the two halves of the pte in
different order.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
In principle update_va_mapping is a good match for set_pte_at, since
it gets the address being mapped, which allows Xen to use its linear
pagetable mapping.
However that assumes that the pmd for the address is attached to the
current pagetable, which may not be true for a given user address space
because the kernel pmd is not shared (at least on 32-bit guests).
Normally the kernel will automatically sync a missing part of the
pagetable with the init_mm pagetable transparently via faults, but that
fails when a missing address is passed to Xen.
And while the linear pagetable mapping is very useful for 32-bit Xen
(as it avoids an explicit domain mapping), 32-bit Xen is deprecated.
64-bit Xen has all memory mapped all the time, so it makes no real
difference.
The upshot is that we should use mmu_update, since it can operate on
non-current pagetables or detached pagetables.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Xen can work out when we're doing IO mappings for itself, so we don't
need to do anything special, and the extra tests just clog things up.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
* 'timers-clocksource-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
clocksource: convert mips to generic i8253 clocksource
clocksource: convert x86 to generic i8253 clocksource
clocksource: convert footbridge to generic i8253 clocksource
clocksource: add common i8253 PIT clocksource
blackfin: convert to clocksource_register_hz
mips: convert to clocksource_register_hz/khz
sparc: convert to clocksource_register_hz/khz
alpha: convert to clocksource_register_hz
microblaze: convert to clocksource_register_hz/khz
ia64: convert to clocksource_register_hz/khz
x86: Convert remaining x86 clocksources to clocksource_register_hz/khz
Make clocksource name const
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (60 commits)
sched: Fix and optimise calculation of the weight-inverse
sched: Avoid going ahead if ->cpus_allowed is not changed
sched, rt: Update rq clock when unthrottling of an otherwise idle CPU
sched: Remove unused parameters from sched_fork() and wake_up_new_task()
sched: Shorten the construction of the span cpu mask of sched domain
sched: Wrap the 'cfs_rq->nr_spread_over' field with CONFIG_SCHED_DEBUG
sched: Remove unused 'this_best_prio arg' from balance_tasks()
sched: Remove noop in alloc_rt_sched_group()
sched: Get rid of lock_depth
sched: Remove obsolete comment from scheduler_tick()
sched: Fix sched_domain iterations vs. RCU
sched: Next buddy hint on sleep and preempt path
sched: Make set_*_buddy() work on non-task entities
sched: Remove need_migrate_task()
sched: Move the second half of ttwu() to the remote cpu
sched: Restructure ttwu() some more
sched: Rename ttwu_post_activation() to ttwu_do_wakeup()
sched: Remove rq argument from ttwu_stat()
sched: Remove rq->lock from the first half of ttwu()
sched: Drop rq->lock from sched_exec()
...
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: Fix rt_rq runtime leakage bug
* 'stable/irq' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: do not clear and mask evtchns in __xen_evtchn_do_upcall
* 'stable/p2m.bugfixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/p2m: Create entries in the P2M_MFN trees's to track 1-1 mappings
* 'stable/e820.bugfixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/setup: Fix for incorrect xen_extra_mem_start initialization under 32-bit
xen/setup: Ignore E820_UNUSABLE when setting 1-1 mappings.
* 'stable/mmu.bugfixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen mmu: fix a race window causing leave_mm BUG()
* 'stable/backend.base.v3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pci: Fix compiler error when CONFIG_XEN_PRIVILEGED_GUEST is not set.
xen/p2m: Add EXPORT_SYMBOL_GPL to the M2P override functions.
xen/p2m/m2p/gnttab: Support GNTMAP_host_map in the M2P override.
xen/irq: The Xen hypervisor cleans up the PIRQs if the other domain forgot.
xen/irq: Export 'xen_pirq_from_irq' function.
xen/irq: Add support to check if IRQ line is shared with other domains.
xen/irq: Check if the PCI device is owned by a domain different than DOMID_SELF.
xen/pci: Add xen_[find|register|unregister]_device_domain_owner functions.
* 'stable/gntalloc.v7' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/gntdev,gntalloc: Remove unneeded VM flags
Cleanup code/data sections definitions
accordingly to include/linux/init.h.
Signed-off-by: Daniel Kiper <dkiper@net-space.pl>
[v1: Rebased on top of latest linus's to include fixes in mmu.c]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Conflicts:
arch/ia64/kernel/cyclone.c
arch/mips/kernel/i8253.c
arch/x86/kernel/i8253.c
Reason: Resolve conflicts so further cleanups do not conflict further
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
.. when applicable. We need to track in the p2m_mfn and
p2m_mfn_p the MFNs and pointers, respectivly, for the P2M entries
that are allocated for the identity mappings. Without this,
a PV domain with an E820 that triggers the 1-1 mapping to kick in,
won't be able to be restored as the P2M won't have the identity
mappings.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
git commit 24bdb0b62c (xen: do not create
the extra e820 region at an addr lower than 4G) does not take into
account that ifdef CONFIG_X86_32 instead of e820_end_of_low_ram_pfn()
find_low_pfn_range() is called (both calls are from arch/x86/kernel/setup.c).
find_low_pfn_range() behaves correctly and does not require change in
xen_extra_mem_start initialization. Additionally, if xen_extra_mem_start
is initialized in the same way as ifdef CONFIG_X86_64 then memory hotplug
support for Xen balloon driver (under development) is broken.
Signed-off-by: Daniel Kiper <dkiper@net-space.pl>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When we parse the raw E820, the Xen hypervisor can set "E820_RAM"
to "E820_UNUSABLE" if the mem=X argument is used. As such we
should _not_ consider the E820_UNUSABLE as an 1-1 identity
mapping, but instead use the same case as for E820_RAM.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Introduce a new x86_init hook called pagetable_reserve that at the end
of init_memory_mapping is used to reserve a range of memory addresses for
the kernel pagetable pages we used and free the other ones.
On native it just calls memblock_x86_reserve_range while on xen it also
takes care of setting the spare memory previously allocated
for kernel pagetable pages from RO to RW, so that it can be used for
other purposes.
A detailed explanation of the reason why this hook is needed follows.
As a consequence of the commit:
commit 4b239f458c
Author: Yinghai Lu <yinghai@kernel.org>
Date: Fri Dec 17 16:58:28 2010 -0800
x86-64, mm: Put early page table high
at some point init_memory_mapping is going to reach the pagetable pages
area and map those pages too (mapping them as normal memory that falls
in the range of addresses passed to init_memory_mapping as argument).
Some of those pages are already pagetable pages (they are in the range
pgt_buf_start-pgt_buf_end) therefore they are going to be mapped RO and
everything is fine.
Some of these pages are not pagetable pages yet (they fall in the range
pgt_buf_end-pgt_buf_top; for example the page at pgt_buf_end) so they
are going to be mapped RW. When these pages become pagetable pages and
are hooked into the pagetable, xen will find that the guest has already
a RW mapping of them somewhere and fail the operation.
The reason Xen requires pagetables to be RO is that the hypervisor needs
to verify that the pagetables are valid before using them. The validation
operations are called "pinning" (more details in arch/x86/xen/mmu.c).
In order to fix the issue we mark all the pages in the entire range
pgt_buf_start-pgt_buf_top as RO, however when the pagetable allocation
is completed only the range pgt_buf_start-pgt_buf_end is reserved by
init_memory_mapping. Hence the kernel is going to crash as soon as one
of the pages in the range pgt_buf_end-pgt_buf_top is reused (b/c those
ranges are RO).
For this reason we need a hook to reserve the kernel pagetable pages we
used and free the other ones so that they can be reused for other
purposes.
On native it just means calling memblock_x86_reserve_range, on Xen it
also means marking RW the pagetable pages that we allocated before but
that haven't been used before.
Another way to fix this is without using the hook is by adding a 'if
(xen_pv_domain)' in the 'init_memory_mapping' code and calling the Xen
counterpart, but that is just nasty.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
mask_rw_pte is currently checking if a pfn is a pagetable page if it
falls in the range pgt_buf_start - pgt_buf_end but that is incorrect
because pgt_buf_end is a moving target: pgt_buf_top is the real
boundary.
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
As a consequence of the commit:
commit 4b239f458c
Author: Yinghai Lu <yinghai@kernel.org>
Date: Fri Dec 17 16:58:28 2010 -0800
x86-64, mm: Put early page table high
it causes the Linux kernel to crash under Xen:
mapping kernel into physical memory
Xen: setup ISA identity maps
about to get started...
(XEN) mm.c:2466:d0 Bad type (saw 7400000000000001 != exp 1000000000000000) for mfn b1d89 (pfn bacf7)
(XEN) mm.c:3027:d0 Error while pinning mfn b1d89
(XEN) traps.c:481:d0 Unhandled invalid opcode fault/trap [#6] on VCPU 0 [ec=0000]
(XEN) domain_crash_sync called from entry.S
(XEN) Domain 0 (vcpu#0) crashed on cpu#0:
...
The reason is that at some point init_memory_mapping is going to reach
the pagetable pages area and map those pages too (mapping them as normal
memory that falls in the range of addresses passed to init_memory_mapping
as argument). Some of those pages are already pagetable pages (they are
in the range pgt_buf_start-pgt_buf_end) therefore they are going to be
mapped RO and everything is fine.
Some of these pages are not pagetable pages yet (they fall in the range
pgt_buf_end-pgt_buf_top; for example the page at pgt_buf_end) so they
are going to be mapped RW. When these pages become pagetable pages and
are hooked into the pagetable, xen will find that the guest has already
a RW mapping of them somewhere and fail the operation.
The reason Xen requires pagetables to be RO is that the hypervisor needs
to verify that the pagetables are valid before using them. The validation
operations are called "pinning" (more details in arch/x86/xen/mmu.c).
In order to fix the issue we mark all the pages in the entire range
pgt_buf_start-pgt_buf_top as RO, however when the pagetable allocation
is completed only the range pgt_buf_start-pgt_buf_end is reserved by
init_memory_mapping. Hence the kernel is going to crash as soon as one
of the pages in the range pgt_buf_end-pgt_buf_top is reused (b/c those
ranges are RO).
For this reason, this function is introduced which is called _after_
the init_memory_mapping has completed (in a perfect world we would
call this function from init_memory_mapping, but lets ignore that).
Because we are called _after_ init_memory_mapping the pgt_buf_[start,
end,top] have all changed to new values (b/c another init_memory_mapping
is called). Hence, the first time we enter this function, we save
away the pgt_buf_start value and update the pgt_buf_[end,top].
When we detect that the "old" pgt_buf_start through pgt_buf_end
PFNs have been reserved (so memblock_x86_reserve_range has been called),
we immediately set out to RW the "old" pgt_buf_end through pgt_buf_top.
And then we update those "old" pgt_buf_[end|top] with the new ones
so that we can redo this on the next pagetable.
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Reviewed-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
[v1: Updated with Jeremy's comments]
[v2: Added the crash output]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If the backends, which use these two functions, are compiled as
a module we need these two functions to be exported.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The two "is_early_ioremap_ptep" checks in mask_rw_pte are only used on
x86_64, in fact early_ioremap is not used at all to setup the initial
pagetable on x86_32.
Moreover on x86_32 the two checks are wrong because the range
pgt_buf_start..pgt_buf_end initially should be mapped RW because
the pages in the range are not pagetable pages yet and haven't been
cleared yet. Afterwards considering the pgt_buf_start..pgt_buf_end is
part of the initial mapping, xen_alloc_pte is capable of turning
the ptes RO when they become pagetable pages.
Fix the issue and improve the readability of the code providing two
different implementation of mask_rw_pte for x86_32 and x86_64.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Do not add the extra e820 region at a physical address lower than 4G
because it breaks e820_end_of_low_ram_pfn().
It is OK for us to move the xen_extra_mem_start up and down because this
is the index of the memory that can be ballooned in/out - it is memory
not available to the kernel during bootup.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We only supported the M2P (and P2M) override only for the
GNTMAP_contains_pte type mappings. Meaning that we grants
operations would "contain the machine address of the PTE to update"
If the flag is unset, then the grant operation is
"contains a host virtual address". The latter case means that
the Hypervisor takes care of updating our page table
(specifically the PTE entry) with the guest's MFN. As such we should
not try to do anything with the PTE. Previous to this patch
we would try to clear the PTE which resulted in Xen hypervisor
being upset with us:
(XEN) mm.c:1066:d0 Attempt to implicitly unmap a granted PTE c0100000ccc59067
(XEN) domain_crash called from mm.c:1067
(XEN) Domain 0 (vcpu#0) crashed on cpu#3:
(XEN) ----[ Xen-4.0-110228 x86_64 debug=y Not tainted ]----
and crashing us.
This patch allows us to inhibit the PTE clearing in the PV guest
if the GNTMAP_contains_pte is not set.
On the m2p_remove_override path we provide the same parameter.
Sadly in the grant-table driver we do not have a mechanism to
tell m2p_remove_override whether to clear the PTE or not. Since
the grant-table driver is used by user-space, we can safely assume
that it operates only on PTE's. Hence the implementation for
it to work on !GNTMAP_contains_pte returns -EOPNOTSUPP. In the future
we can implement the support for this. It will require some extra
accounting structure to keep track of the page[i], and the flag.
[v1: Added documentation details, made it return -EOPNOTSUPP instead
of trying to do a half-way implementation]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
For future rework of try_to_wake_up() we'd like to push part of that
function onto the CPU the task is actually going to run on.
In order to do so we need a generic callback from the existing scheduler IPI.
This patch introduces such a generic callback: scheduler_ipi() and
implements it as a NOP.
BenH notes: PowerPC might use this IPI on offline CPUs under rare conditions!
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reviewed-by: Frank Rowand <frank.rowand@am.sony.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110405152728.744338123@chello.nl
Make XEN_SAVE_RESTORE select HIBERNATE_CALLBACKS.
Remove XEN_SAVE_RESTORE dependency from PM_SLEEP.
Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Xen fails to mask XSAVE from the cpuid feature, despite not historically
supporting guest use of XSAVE. However, now that XSAVE support has been
added to Xen, we need to reliably detect its presence.
The most reliable way to do this is to look at the OSXSAVE feature in
cpuid which is set iff the OS (Xen, in this case), has set
CR4.OSXSAVE.
[ Cleaned up conditional a bit. - Jeremy ]
Signed-off-by: Shan Haitao <haitao.shan@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Some (old) versions of Xen just kill the domain if it tries to set any
unknown bits in CR4, so we can't reliably probe for OSXSAVE in
CR4.
Since Xen doesn't support XSAVE for guests at the moment, and no such
support is being worked on, there's no downside in just unconditionally
masking XSAVE support.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
There are valid situations in which this error is not
a warning. Mainly when QEMU maps a guest memory and uses
the VM_IO flag to set the MFNs. For right now make the
WARN be WARN_ONCE. In the future we will:
1). Remove the VM_IO code handling..
2). .. which will also remove this debug facility.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Fix section mismatch warnings:
set_phys_range_identity() is called by __init xen_set_identity(),
so also mark set_phys_range_identity() as __init.
then:
__early_alloc_p2m() is called set_phys_range_identity(), so also mark
__early_alloc_p2m() as __init.
WARNING: arch/x86/built-in.o(.text+0x7856): Section mismatch in reference from the function __early_alloc_p2m() to the function .init.text:extend_brk()
The function __early_alloc_p2m() references
the function __init extend_brk().
This is often because __early_alloc_p2m lacks a __init
annotation or the annotation of extend_brk is wrong.
WARNING: arch/x86/built-in.o(.text+0x7967): Section mismatch in reference from the function set_phys_range_identity() to the function .init.text:extend_brk()
The function set_phys_range_identity() references
the function __init extend_brk().
This is often because set_phys_range_identity lacks a __init
annotation or the annotation of extend_brk is wrong.
[v2: Per Stephen Hemming recommonedation made __early_alloc_p2m static]
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
It is possible to add a p2m override on pages that are currently mapped
to INVALID_P2M_ENTRY; in particular, this will happen when using
ballooned pages in gntdev. This means that set_phys_to_machine must be
used instead of __set_phys_to_machine.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
xen: update mask_rw_pte after kernel page tables init changes
xen: set max_pfn_mapped to the last pfn mapped
x86: Cleanup highmap after brk is concluded
Fix up trivial onflict (added header file includes) in
arch/x86/mm/init_64.c
After "x86-64, mm: Put early page table high" already existing kernel
page table pages can be mapped using early_ioremap too so we need to
update mask_rw_pte to make sure these pages are still mapped RO.
The reason why we have to do that is explain by the commit message of
fef5ba797991f9335bcfc295942b684f9bf613a1:
"Xen requires that all pages containing pagetable entries to be mapped
read-only. If pages used for the initial pagetable are already mapped
then we can change the mapping to RO. However, if they are initially
unmapped, we need to make sure that when they are later mapped, they
are also mapped RO.
..SNIP..
the pagetable setup code early_ioremaps the pages to write their
entries, so we must make sure that mappings created in the early_ioremap
fixmap area are mapped RW. (Those mappings are removed before the pages
are presented to Xen as pagetable pages.)"
We accomplish all this in mask_rw_pte by mapping RO all the pages mapped
using early_ioremap apart from the last one that has been allocated
because it is not a page table page yet (it has not been hooked into the
page tables yet).
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
LKML-Reference: <alpine.DEB.2.00.1103171739050.3382@kaball-desktop>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Do not set max_pfn_mapped to the end of the initial memory mappings,
that also contain pages that don't belong in pfn space (like the mfn
list).
Set max_pfn_mapped to the last real pfn mapped in the initial memory
mappings that is the pfn backing _end.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
LKML-Reference: <alpine.DEB.2.00.1103171739050.3382@kaball-desktop>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Flush TLB if PGD entry is changed in i386 PAE mode
x86, dumpstack: Correct stack dump info when frame pointer is available
x86: Clean up csum-copy_64.S a bit
x86: Fix common misspellings
x86: Fix misspelling and align params
x86: Use PentiumPro-optimized partial_csum() on VIA C7
They were generated by 'codespell' and then manually reviewed.
Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: trivial@kernel.org
LKML-Reference: <1300389856-1099-3-git-send-email-lucas.demarchi@profusion.mobi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'stable/hvc-console' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/hvc: Disable probe_irq_on/off from poking the hvc-console IRQ line.
* 'stable/gntalloc.v6' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: gntdev: fix build warning
xen/p2m/m2p/gnttab: do not add failed grant maps to m2p override
xen-gntdev: Add cast to pointer
xen-gntdev: Fix incorrect use of zero handle
xen: change xen/[gntdev/gntalloc] to default m
xen-gntdev: prevent using UNMAP_NOTIFY_CLEAR_BYTE on read-only mappings
xen-gntdev: Avoid double-mapping memory
xen-gntdev: Avoid unmapping ranges twice
xen-gntdev: Use map->vma for checking map validity
xen-gntdev: Fix unmap notify on PV domains
xen-gntdev: Fix memory leak when mmap fails
xen/gntalloc,gntdev: Add unmap notify ioctl
xen-gntalloc: Userspace grant allocation driver
xen-gntdev: Support mapping in HVM domains
xen-gntdev: Add reference counting to maps
xen-gntdev: Use find_vma rather than iterating our vma list manually
xen-gntdev: Change page limit to be global instead of per-open
* 'stable/balloon' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (24 commits)
xen-gntdev: Use ballooned pages for grant mappings
xen-balloon: Add interface to retrieve ballooned pages
xen-balloon: Move core balloon functionality out of module
xen/balloon: Remove pr_info's and don't alter retry_count
xen/balloon: Protect against CPU exhaust by event/x process
xen/balloon: Migration from mod_timer() to schedule_delayed_work()
xen/balloon: Removal of driver_pages
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6: (21 commits)
PM / Hibernate: Reduce autotuned default image size
PM / Core: Introduce struct syscore_ops for core subsystems PM
PM QoS: Make pm_qos settings readable
PM / OPP: opp_find_freq_exact() documentation fix
PM: Documentation/power/states.txt: fix repetition
PM: Make system-wide PM and runtime PM treat subsystems consistently
PM: Simplify kernel/power/Kconfig
PM: Add support for device power domains
PM: Drop pm_flags that is not necessary
PM: Allow pm_runtime_suspend() to succeed during system suspend
PM: Clean up PM_TRACE dependencies and drop unnecessary Kconfig option
PM: Remove CONFIG_PM_OPS
PM: Reorder power management Kconfig options
PM: Make CONFIG_PM depend on (CONFIG_PM_SLEEP || CONFIG_PM_RUNTIME)
PM / ACPI: Remove references to pm_flags from bus.c
PM: Do not create wakeup sysfs files for devices that cannot wake up
USB / Hub: Do not call device_set_wakeup_capable() under spinlock
PM: Use appropriate printk() priority level in trace.c
PM / Wakeup: Don't update events_check_enabled in pm_get_wakeup_count()
PM / Wakeup: Make pm_save_wakeup_count() work as documented
...
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (93 commits)
x86, tlb, UV: Do small micro-optimization for native_flush_tlb_others()
x86-64, NUMA: Don't call numa_set_distanc() for all possible node combinations during emulation
x86-64, NUMA: Don't assume phys node 0 is always online in numa_emulation()
x86-64, NUMA: Clean up initmem_init()
x86-64, NUMA: Fix numa_emulation code with node0 without RAM
x86-64, NUMA: Revert NUMA affine page table allocation
x86: Work around old gas bug
x86-64, NUMA: Better explain numa_distance handling
x86-64, NUMA: Fix distance table handling
mm: Move early_node_map[] reverse scan helpers under HAVE_MEMBLOCK
x86-64, NUMA: Fix size of numa_distance array
x86: Rename e820_table_* to pgt_buf_*
bootmem: Move __alloc_memory_core_early() to nobootmem.c
bootmem: Move contig_page_data definition to bootmem.c/nobootmem.c
bootmem: Separate out CONFIG_NO_BOOTMEM code into nobootmem.c
x86-64, NUMA: Seperate out numa_alloc_distance() from numa_set_distance()
x86-64, NUMA: Add proper function comments to global functions
x86-64, NUMA: Move NUMA emulation into numa_emulation.c
x86-64, NUMA: Prepare numa_emulation() for moving NUMA emulation into a separate file
x86-64, NUMA: Do not scan two times for setup_node_bootmem()
...
Fix up conflicts in arch/x86/kernel/smpboot.c
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, binutils, xen: Fix another wrong size directive
x86: Remove dead config option X86_CPU
x86: Really print supported CPUs if PROCESSOR_SELECT=y
x86: Fix a bogus unwind annotation in lib/semaphore_32.S
um, x86-64: Fix UML build after adding CFI annotations to lib/rwsem_64.S
x86: Remove unused bits from lib/thunk_*.S
x86: Use {push,pop}_cfi in more places
x86-64: Add CFI annotations to lib/rwsem_64.S
x86, asm: Cleanup unnecssary macros in asm-offsets.c
x86, system.h: Drop unused __SAVE/__RESTORE macros
x86: Use bitmap library functions
x86: Partly unify asm-offsets_{32,64}.c
x86: Reduce back the alignment of the per-CPU data section
* 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm:
xen: suspend: remove xen_hvm_suspend
xen: suspend: pull pre/post suspend hooks out into suspend_info
xen: suspend: move arch specific pre/post suspend hooks into generic hooks
xen: suspend: refactor non-arch specific pre/post suspend hooks
xen: suspend: add "arch" to pre/post suspend hooks
xen: suspend: pass extra hypercall argument via suspend_info struct
xen: suspend: refactor cancellation flag into a structure
xen: suspend: use HYPERVISOR_suspend for PVHVM case instead of open coding
xen: switch to new schedop hypercall by default.
xen: use new schedop interface for suspend
xen: do not respond to unknown xenstore control requests
xen: fix compile issue if XEN is enabled but XEN_PVHVM is disabled
xen: PV on HVM: support PV spinlocks and IPIs
xen: make the ballon driver work for hvm domains
xen-blkfront: handle Xen major numbers other than XENVBD
xen: do not use xen_info on HVM, set pv_info name to "Xen HVM"
xen: no need to delay xen_setup_shutdown_event for hvm guests anymore
* 'stable/ia64' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: ia64 build broken due to "xen: switch to new schedop hypercall by default."
* 'stable/blkfront-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: Union the blkif_request request specific fields
* 'stable/cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: annotate functions which only call into __init at start of day
xen p2m: annotate variable which appears unused
xen: events: mark cpu_evtchn_mask_p as __refdata
* 'stable/irq.rework' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/irq: Cleanup up the pirq_to_irq for DomU PV PCI passthrough guests as well.
xen: Use IRQF_FORCE_RESUME
xen/timer: Missing IRQF_NO_SUSPEND in timer code broke suspend.
xen: Fix compile error introduced by "switch to new irq_chip functions"
xen: Switch to new irq_chip functions
xen: Remove stale irq_chip.end
xen: events: do not free legacy IRQs
xen: events: allocate GSIs and dynamic IRQs from separate IRQ ranges.
xen: events: add xen_allocate_irq_{dynamic, gsi} and xen_free_irq
xen:events: move find_unbound_irq inside CONFIG_PCI_MSI
xen: handled remapped IRQs when enabling a pcifront PCI device.
genirq: Add IRQF_FORCE_RESUME
* 'stable/pcifront-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
pci/xen: When free-ing MSI-X/MSI irq->desc also use generic code.
pci/xen: Cleanup: convert int** to int[]
pci/xen: Use xen_allocate_pirq_msi instead of xen_allocate_pirq
xen-pcifront: Sanity check the MSI/MSI-X values
xen-pcifront: don't use flush_scheduled_work()
* 'stable/p2m-identity.v4.9.1' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/m2p: Check whether the MFN has IDENTITY_FRAME bit set..
xen/m2p: No need to catch exceptions when we know that there is no RAM
xen/debug: WARN_ON when identity PFN has no _PAGE_IOMAP flag set.
xen/debugfs: Add 'p2m' file for printing out the P2M layout.
xen/setup: Set identity mapping for non-RAM E820 and E820 gaps.
xen/mmu: WARN_ON when racing to swap middle leaf.
xen/mmu: Set _PAGE_IOMAP if PFN is an identity PFN.
xen/mmu: Add the notion of identity (1-1) mapping.
xen: Mark all initial reserved pages for the balloon as INVALID_P2M_ENTRY.
* 'stable/e820' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/e820: Don't mark balloon memory as E820_UNUSABLE when running as guest and fix overflow.
xen/setup: Inhibit resource API from using System RAM E820 gaps as PCI mem gaps.
From the users' point of view CONFIG_PM is really only used for
making it possible to set CONFIG_SUSPEND, CONFIG_HIBERNATION,
CONFIG_PM_RUNTIME and (surprisingly enough) CONFIG_XEN_SAVE_RESTORE
(CONFIG_PM_OPP also depends on CONFIG_PM, but quite artificially).
However, both CONFIG_SUSPEND and CONFIG_HIBERNATION require platform
support (independent of CONFIG_PM) and it is not quite obvious that
CONFIG_PM has to be set for CONFIG_XEN_SAVE_RESTORE to be available.
Thus, from the users' point of view, it would be more logical to
automatically select CONFIG_PM if any of the above options depending
on it are set.
Make CONFIG_PM depend on (CONFIG_PM_SLEEP || CONFIG_PM_RUNTIME),
which will cause it to be selected when any of CONFIG_SUSPEND,
CONFIG_HIBERNATION, CONFIG_PM_RUNTIME, CONFIG_XEN_SAVE_RESTORE is
set and will clarify its meaning.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Removal of driver_pages (I do not have seen any references to it).
Signed-off-by: Daniel Kiper <dkiper@net-space.pl>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Only enabled if XEN_DEBUG is enabled. We print a warning
when:
pfn_to_mfn(pfn) == pfn, but no VM_IO (_PAGE_IOMAP) flag set
(and pfn is an identity mapped pfn)
pfn_to_mfn(pfn) != pfn, and VM_IO flag is set.
(ditto, pfn is an identity mapped pfn)
[v2: Make it dependent on CONFIG_XEN_DEBUG instead of ..DEBUG_FS]
[v3: Fix compiler warning]
Reviewed-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We walk over the whole P2M tree and construct a simplified view of
which PFN regions belong to what level and what type they are.
Only enabled if CONFIG_XEN_DEBUG_FS is set.
[v2: UNKN->UNKNOWN, use uninitialized_var]
[v3: Rebased on top of mmu->p2m code split]
[v4: Fixed the else if]
Reviewed-by: Ian Campbell <Ian.Campbell@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We walk the E820 region and start at 0 (for PV guests we start
at ISA_END_ADDRESS) and skip any E820 RAM regions. For all other
regions and as well the gaps we set them to be identity mappings.
The reasons we do not want to set the identity mapping from 0->
ISA_END_ADDRESS when running as PV is b/c that the kernel would
try to read DMI information and fail (no permissions to read that).
There is a lot of gnarly code to deal with that weird region so
we won't try to do a cleanup in this patch.
This code ends up calling 'set_phys_to_identity' with the start
and end PFN of the the E820 that are non-RAM or have gaps.
On 99% of machines that means one big region right underneath the
4GB mark. Usually starts at 0xc0000 (or 0x80000) and goes to
0x100000.
[v2: Fix for E820 crossing 1MB region and clamp the start]
[v3: Squshed in code that does this over ranges]
[v4: Moved the comment to the correct spot]
[v5: Use the "raw" E820 from the hypervisor]
[v6: Added Review-by tag]
Reviewed-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The initial bootup code uses set_phys_to_machine quite a lot, and after
bootup it would be used by the balloon driver. The balloon driver does have
mutex lock so this should not be necessary - but just in case, add
a WARN_ON if we do hit this scenario. If we do fail this, it is OK
to continue as there is a backup mechanism (VM_IO) that can bypass
the P2M and still set the _PAGE_IOMAP flags.
[v2: Change from WARN to BUG_ON]
[v3: Rebased on top of xen->p2m code split]
[v4: Change from BUG_ON to WARN]
Reviewed-by: Ian Campbell <Ian.Campbell@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If we find that the PFN is within the P2M as an identity
PFN make sure to tack on the _PAGE_IOMAP flag.
Reviewed-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Our P2M tree structure is a three-level. On the leaf nodes
we set the Machine Frame Number (MFN) of the PFN. What this means
is that when one does: pfn_to_mfn(pfn), which is used when creating
PTE entries, you get the real MFN of the hardware. When Xen sets
up a guest it initially populates a array which has descending
(or ascending) MFN values, as so:
idx: 0, 1, 2
[0x290F, 0x290E, 0x290D, ..]
so pfn_to_mfn(2)==0x290D. If you start, restart many guests that list
starts looking quite random.
We graft this structure on our P2M tree structure and stick in
those MFN in the leafs. But for all other leaf entries, or for the top
root, or middle one, for which there is a void entry, we assume it is
"missing". So
pfn_to_mfn(0xc0000)=INVALID_P2M_ENTRY.
We add the possibility of setting 1-1 mappings on certain regions, so
that:
pfn_to_mfn(0xc0000)=0xc0000
The benefit of this is, that we can assume for non-RAM regions (think
PCI BARs, or ACPI spaces), we can create mappings easily b/c we
get the PFN value to match the MFN.
For this to work efficiently we introduce one new page p2m_identity and
allocate (via reserved_brk) any other pages we need to cover the sides
(1GB or 4MB boundary violations). All entries in p2m_identity are set to
INVALID_P2M_ENTRY type (Xen toolstack only recognizes that and MFNs,
no other fancy value).
On lookup we spot that the entry points to p2m_identity and return the identity
value instead of dereferencing and returning INVALID_P2M_ENTRY. If the entry
points to an allocated page, we just proceed as before and return the PFN.
If the PFN has IDENTITY_FRAME_BIT set we unmask that in appropriate functions
(pfn_to_mfn).
The reason for having the IDENTITY_FRAME_BIT instead of just returning the
PFN is that we could find ourselves where pfn_to_mfn(pfn)==pfn for a
non-identity pfn. To protect ourselves against we elect to set (and get) the
IDENTITY_FRAME_BIT on all identity mapped PFNs.
This simplistic diagram is used to explain the more subtle piece of code.
There is also a digram of the P2M at the end that can help.
Imagine your E820 looking as so:
1GB 2GB
/-------------------+---------\/----\ /----------\ /---+-----\
| System RAM | Sys RAM ||ACPI| | reserved | | Sys RAM |
\-------------------+---------/\----/ \----------/ \---+-----/
^- 1029MB ^- 2001MB
[1029MB = 263424 (0x40500), 2001MB = 512256 (0x7D100), 2048MB = 524288 (0x80000)]
And dom0_mem=max:3GB,1GB is passed in to the guest, meaning memory past 1GB
is actually not present (would have to kick the balloon driver to put it in).
When we are told to set the PFNs for identity mapping (see patch: "xen/setup:
Set identity mapping for non-RAM E820 and E820 gaps.") we pass in the start
of the PFN and the end PFN (263424 and 512256 respectively). The first step is
to reserve_brk a top leaf page if the p2m[1] is missing. The top leaf page
covers 512^2 of page estate (1GB) and in case the start or end PFN is not
aligned on 512^2*PAGE_SIZE (1GB) we loop on aligned 1GB PFNs from start pfn to
end pfn. We reserve_brk top leaf pages if they are missing (means they point
to p2m_mid_missing).
With the E820 example above, 263424 is not 1GB aligned so we allocate a
reserve_brk page which will cover the PFNs estate from 0x40000 to 0x80000.
Each entry in the allocate page is "missing" (points to p2m_missing).
Next stage is to determine if we need to do a more granular boundary check
on the 4MB (or 2MB depending on architecture) off the start and end pfn's.
We check if the start pfn and end pfn violate that boundary check, and if
so reserve_brk a middle (p2m[x][y]) leaf page. This way we have a much finer
granularity of setting which PFNs are missing and which ones are identity.
In our example 263424 and 512256 both fail the check so we reserve_brk two
pages. Populate them with INVALID_P2M_ENTRY (so they both have "missing" values)
and assign them to p2m[1][2] and p2m[1][488] respectively.
At this point we would at minimum reserve_brk one page, but could be up to
three. Each call to set_phys_range_identity has at maximum a three page
cost. If we were to query the P2M at this stage, all those entries from
start PFN through end PFN (so 1029MB -> 2001MB) would return INVALID_P2M_ENTRY
("missing").
The next step is to walk from the start pfn to the end pfn setting
the IDENTITY_FRAME_BIT on each PFN. This is done in 'set_phys_range_identity'.
If we find that the middle leaf is pointing to p2m_missing we can swap it over
to p2m_identity - this way covering 4MB (or 2MB) PFN space. At this point we
do not need to worry about boundary aligment (so no need to reserve_brk a middle
page, figure out which PFNs are "missing" and which ones are identity), as that
has been done earlier. If we find that the middle leaf is not occupied by
p2m_identity or p2m_missing, we dereference that page (which covers
512 PFNs) and set the appropriate PFN with IDENTITY_FRAME_BIT. In our example
263424 and 512256 end up there, and we set from p2m[1][2][256->511] and
p2m[1][488][0->256] with IDENTITY_FRAME_BIT set.
All other regions that are void (or not filled) either point to p2m_missing
(considered missing) or have the default value of INVALID_P2M_ENTRY (also
considered missing). In our case, p2m[1][2][0->255] and p2m[1][488][257->511]
contain the INVALID_P2M_ENTRY value and are considered "missing."
This is what the p2m ends up looking (for the E820 above) with this
fabulous drawing:
p2m /--------------\
/-----\ | &mfn_list[0],| /-----------------\
| 0 |------>| &mfn_list[1],| /---------------\ | ~0, ~0, .. |
|-----| | ..., ~0, ~0 | | ~0, ~0, [x]---+----->| IDENTITY [@256] |
| 1 |---\ \--------------/ | [p2m_identity]+\ | IDENTITY [@257] |
|-----| \ | [p2m_identity]+\\ | .... |
| 2 |--\ \-------------------->| ... | \\ \----------------/
|-----| \ \---------------/ \\
| 3 |\ \ \\ p2m_identity
|-----| \ \-------------------->/---------------\ /-----------------\
| .. +->+ | [p2m_identity]+-->| ~0, ~0, ~0, ... |
\-----/ / | [p2m_identity]+-->| ..., ~0 |
/ /---------------\ | .... | \-----------------/
/ | IDENTITY[@0] | /-+-[x], ~0, ~0.. |
/ | IDENTITY[@256]|<----/ \---------------/
/ | ~0, ~0, .... |
| \---------------/
|
p2m_missing p2m_missing
/------------------\ /------------\
| [p2m_mid_missing]+---->| ~0, ~0, ~0 |
| [p2m_mid_missing]+---->| ..., ~0 |
\------------------/ \------------/
where ~0 is INVALID_P2M_ENTRY. IDENTITY is (PFN | IDENTITY_BIT)
Reviewed-by: Ian Campbell <ian.campbell@citrix.com>
[v5: Changed code to use ranges, added ASCII art]
[v6: Rebased on top of xen->p2m code split]
[v4: Squished patches in just this one]
[v7: Added RESERVE_BRK for potentially allocated pages]
[v8: Fixed alignment problem]
[v9: Changed 1<<3X to 1<<BITS_PER_LONG-X]
[v10: Copied git commit description in the p2m code + Add Review tag]
[v11: Title had '2-1' - should be '1-1' mapping]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If we have a guest that asked for:
memory=1024
maxmem=2048
Which means we want 1GB now, and create pagetables so that we can expand
up to 2GB, we would have this E820 layout:
[ 0.000000] BIOS-provided physical RAM map:
[ 0.000000] Xen: 0000000000000000 - 00000000000a0000 (usable)
[ 0.000000] Xen: 00000000000a0000 - 0000000000100000 (reserved)
[ 0.000000] Xen: 0000000000100000 - 0000000080800000 (usable)
Due to patch: "xen/setup: Inhibit resource API from using System RAM E820 gaps as PCI mem gaps."
we would mark the memory past the 1GB mark as unusuable resulting in:
[ 0.000000] BIOS-provided physical RAM map:
[ 0.000000] Xen: 0000000000000000 - 00000000000a0000 (usable)
[ 0.000000] Xen: 00000000000a0000 - 0000000000100000 (reserved)
[ 0.000000] Xen: 0000000000100000 - 0000000040000000 (usable)
[ 0.000000] Xen: 0000000040000000 - 0000000080800000 (unusable)
which meant that we could not balloon up anymore. We could
balloon the guest down. The fix is to run the code introduced
by the above mentioned patch only for the initial domain.
We will have to revisit this once we start introducing a modified
E820 for PCI passthrough so that we can utilize the P2M identity code.
We also fix an overflow by having UL instead of ULL on 32-bit machines.
[v2: Ian pointed to the overflow issue]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
It's forbidden to take the page_table_lock with the irq disabled
or if there's contention the IPIs (for tlb flushes) sent with
the page_table_lock held will never run leading to a deadlock.
Nobody takes the pgd_lock from irq context so the _irqsave can be
removed.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: <stable@kernel.org>
LKML-Reference: <201102162345.p1GNjMjm021738@imap1.linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The patches missed an indirect use of IRQF_NO_SUSPEND pulled in via
IRQF_TIMER. The following patch fixes the issue.
With this fixlet PV guest migration works just fine. I also booted the
entire series as a dom0 kernel and it appeared fine.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
With this patch, we diligently set regions that will be used by the
balloon driver to be INVALID_P2M_ENTRY and under the ownership
of the balloon driver. We are OK using the __set_phys_to_machine
as we do not expect to be allocating any P2M middle or entries pages.
The set_phys_to_machine has the side-effect of potentially allocating
new pages and we do not want that at this stage.
We can do this because xen_build_mfn_list_list will have already
allocated all such pages up to xen_max_p2m_pfn.
We also move the check for auto translated physmap down the
stack so it is present in __set_phys_to_machine.
[v2: Rebased with mmu->p2m code split]
Reviewed-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
PAGE_SIZE_asm, PAGE_SHIFT_asm, THREAD_SIZE_asm can be safely removed from
asm-offsets.c, and be replaced by their non-'_asm' counterparts in the code
that uses them, since the _AC macro defined in include/linux/const.h makes
PAGE_SIZE/PAGE_SHIFT/THREAD_SIZE work with as.
Signed-off-by: Stratos Psomadakis <psomas@cslab.ece.ntua.gr>
LKML-Reference: <1298666774-17646-2-git-send-email-psomas@cslab.ece.ntua.gr>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
xen_pre_device_suspend is unused on ia64.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Initialize PV spinlocks on boot CPU right after native_smp_prepare_cpus
(that switch to APIC mode and initialize APIC routing); on secondary
CPUs on CPU_UP_PREPARE.
Enable the usage of event channels to send and receive IPIs when
running as a PV on HVM guest.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
e820_table_{start|end|top}, which are used to buffer page table
allocation during early boot, are now derived from memblock and don't
have much to do with e820. Change the names so that they reflect what
they're used for.
This patch doesn't introduce any behavior change.
-v2: Ingo found that earlier patch "x86: Use early pre-allocated page
table buffer top-down" caused crash on 32bit and needed to be
dropped. This patch was updated to reflect the change.
-tj: Updated commit description.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
With the hypervisor argument of dom0_mem=X we iterate over the physical
(only for the initial domain) E820 and subtract the the size from each
E820_RAM region the delta so that the cumulative size of all E820_RAM regions
is equal to 'X'. This sometimes ends up with E820_RAM regions with zero size
(which are removed by e820_sanitize) and E820_RAM that are smaller
than physically.
Later on the PCI API looks at the E820 and attempts to set up an
resource region for the "PCI mem". The E820 (assume dom0_mem=1GB is
set) compared to the physical looks as so:
[ 0.000000] BIOS-provided physical RAM map:
[ 0.000000] Xen: 0000000000000000 - 0000000000097c00 (usable)
[ 0.000000] Xen: 0000000000097c00 - 0000000000100000 (reserved)
-[ 0.000000] Xen: 0000000000100000 - 00000000defafe00 (usable)
+[ 0.000000] Xen: 0000000000100000 - 0000000040000000 (usable)
[ 0.000000] Xen: 00000000defafe00 - 00000000defb1ea0 (ACPI NVS)
[ 0.000000] Xen: 00000000defb1ea0 - 00000000e0000000 (reserved)
[ 0.000000] Xen: 00000000f4000000 - 00000000f8000000 (reserved)
..
And we get
[ 0.000000] Allocating PCI resources starting at 40000000 (gap: 40000000:9efafe00)
while it should have started at e0000000 (a nice big gap up to
f4000000 exists). The "Allocating PCI" is part of the resource API.
The users that end up using those PCI I/O regions usually supply their
own BARs when calling the resource API (request_resource, or allocate_resource),
but there are exceptions which provide an empty 'struct resource' and
expect the API to provide the 'struct resource' to be populated with valid values.
The one that triggered this bug was the intel AGP driver that requested
a region for the flush page (intel_i9xx_setup_flush).
Before this patch, when running under Xen hypervisor, the 'struct resource'
returned could have (depending on the dom0_mem size) physical ranges of a 'System RAM'
instead of 'I/O' regions. This ended up with the Hypervisor failing a request
to populate PTE's with those PFNs as the domain did not have access to those
'System RAM' regions (rightly so).
After this patch, the left-over E820_RAM region from the truncation, will be
labeled as E820_UNUSABLE. The E820 will look as so:
[ 0.000000] BIOS-provided physical RAM map:
[ 0.000000] Xen: 0000000000000000 - 0000000000097c00 (usable)
[ 0.000000] Xen: 0000000000097c00 - 0000000000100000 (reserved)
-[ 0.000000] Xen: 0000000000100000 - 00000000defafe00 (usable)
+[ 0.000000] Xen: 0000000000100000 - 0000000040000000 (usable)
+[ 0.000000] Xen: 0000000040000000 - 00000000defafe00 (unusable)
[ 0.000000] Xen: 00000000defafe00 - 00000000defb1ea0 (ACPI NVS)
[ 0.000000] Xen: 00000000defb1ea0 - 00000000e0000000 (reserved)
[ 0.000000] Xen: 00000000f4000000 - 00000000f8000000 (reserved)
For more information:
http://mid.gmane.org/1A42CE6F5F474C41B63392A5F80372B2335E978C@shsmsx501.ccr.corp.intel.com
BugLink: http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=1726
Signed-off-by: Fengzhe Zhang <fengzhe.zhang@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This converts the remaining x86 clocksources to use
clocksource_register_hz/khz.
CC: jacob.jun.pan@intel.com
CC: Glauber Costa <glommer@redhat.com>
CC: Dimitri Sivanich <sivanich@sgi.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Jeremy Fitzhardinge <jeremy@xensource.com>
CC: Chris McDermott <lcm@us.ibm.com>
CC: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [xen]
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Both xen_hvm_init_shared_info and xen_build_mfn_list_list can be
called at resume time as well as at start of day but only reference
__init functions (extend_brk) at start of day. Hence annotate with
__ref.
WARNING: arch/x86/built-in.o(.text+0x4f1): Section mismatch in reference
from the function xen_hvm_init_shared_info() to the function
.init.text:extend_brk()
The function xen_hvm_init_shared_info() references
the function __init extend_brk().
This is often because xen_hvm_init_shared_info lacks a __init
annotation or the annotation of extend_brk is wrong.
xen_hvm_init_shared_info calls extend_brk() iff !shared_info_page and
initialises shared_info_page with the result. This happens at start of
day only.
WARNING: arch/x86/built-in.o(.text+0x599b): Section mismatch in reference
from the function xen_build_mfn_list_list() to the function
.init.text:extend_brk()
The function xen_build_mfn_list_list() references
the function __init extend_brk().
This is often because xen_build_mfn_list_list lacks a __init
annotation or the annotation of extend_brk is wrong.
(this warning occurs multiple times)
xen_build_mfn_list_list only calls extend_brk() at boot time, while
building the initial mfn list list
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC arch/x86/xen/p2m.o
arch/x86/xen/p2m.c: In function 'm2p_remove_override':
arch/x86/xen/p2m.c:460: warning: 'address' may be used uninitialized in this function
arch/x86/xen/p2m.c: In function 'm2p_add_override':
arch/x86/xen/p2m.c:426: warning: 'address' may be used uninitialized in this function
In actual fact address is inialised in one "if (!PageHighMem(page))"
statement and used in a second and so is always initialised before
use.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
With this patch, the cpuidle driver does not load and
does not issue the mwait operations. Instead the hypervisor
is doing them (b/c we call the safe_halt pvops call).
This fixes quite a lot of bootup issues wherein the user had
to force interrupts for the continuation of the bootup.
Details are discussed in:
http://lists.xensource.com/archives/html/xen-devel/2011-01/msg00535.html
[v2: Wrote the commit description]
Reported-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Tested-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Under Dell Inspiron 1525, and Intel SandyBridge SDP's the
BIOS e820 RAM is not page-aligned:
[ 0.000000] Xen: 0000000000100000 - 00000000df66d800 (usable)
We were not handling that and ended up setting up a pagetable
that included up to df66e000 with the disastrous effect that when
memset(NODE_DATA(nodeid), 0, sizeof(pg_data_t));
tried to clear the page it would crash at the 2K mark.
Initially reported by Michael Young @
http://lists.xensource.com/archives/html/xen-devel/2011-01/msg00108.html
The fix is to page-align the size and also take into consideration
the start of the E820 (in case that is not page-aligned either). This
fixes the bootup failure on those affected machines.
This patch is a rework of the Micheal A Young initial patch and
considers the case if the start is not page-aligned.
Reported-by: Michael A Young <m.a.young@durham.ac.uk>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Michael A Young <m.a.young@durham.ac.uk>
In case the mfn_list does not have enough entries to fill
a p2m page we do not want the entries from max_pfn up to
the boundary to be filled with unknown values. Hence
set them to INVALID_P2M_ENTRY.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
After changing the p2m mapping to a tree by
commit 58e05027b5
xen: convert p2m to a 3 level tree
and trying to boot a DomU with 615MB of memory, the following crash was
observed in the dump:
kernel direct mapping tables up to 26f00000 @ 1ec4000-1fff000
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<c0107397>] xen_set_pte+0x27/0x60
*pdpt = 0000000000000000 *pde = 0000000000000000
Adding further debug statements showed that when trying to set up
pfn=0x26700 the returned mapping was invalid.
pfn=0x266ff calling set_pte(0xc1fe77f8, 0x6b3003)
pfn=0x26700 calling set_pte(0xc1fe7800, 0x3)
Although the last_pfn obtained from the startup info is 0x26700, which
should in turn not be hit, the additional 8MB which are added as extra
memory normally seem to be ok. This lead to looking into the initial
p2m tree construction, which uses the smaller value and assuming that
there is other code handling the extra memory.
When the p2m tree is set up, the leaves are directly pointed to the
array which the domain builder set up. But if the mapping is not on a
boundary that fits into one p2m page, this will result in the last leaf
being only partially valid. And as the invalid entries are not
initialized in that case, things go badly wrong.
I am trying to fix that by checking whether the current leaf is a
complete map and if not, allocate a completely new page and copy only
the valid pointers there. This may not be the most efficient or elegant
solution, but at least it seems to allow me booting DomUs with memory
assignments all over the range.
BugLink: http://bugs.launchpad.net/bugs/686692
[v2: Redid a bit of commit wording and fixed a compile warning]
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Fix sparse warning for non-ANSI function declaration:
arch/x86/xen/irq.c:129:30: warning: non-ANSI function declaration of function 'xen_init_irq_ops'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
During early boot, local IRQ is disabled until IRQ subsystem is
properly initialized. During this time, no one should enable
local IRQ and some operations which usually are not allowed with
IRQ disabled, e.g. operations which might sleep or require
communications with other processors, are allowed.
lockdep tracked this with early_boot_irqs_off/on() callbacks.
As other subsystems need this information too, move it to
init/main.c and make it generally available. While at it,
toggle the boolean to early_boot_irqs_disabled instead of
enabled so that it can be initialized with %false and %true
indicates the exceptional condition.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <20110120110635.GB6036@htj.dyndns.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'stable/gntdev' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/p2m: Fix module linking error.
xen p2m: clear the old pte when adding a page to m2p_override
xen gntdev: use gnttab_map_refs and gnttab_unmap_refs
xen: introduce gnttab_map_refs and gnttab_unmap_refs
xen p2m: transparently change the p2m mappings in the m2p override
xen/gntdev: Fix circular locking dependency
xen/gntdev: stop using "token" argument
xen: gntdev: move use of GNTMAP_contains_pte next to the map_op
xen: add m2p override mechanism
xen: move p2m handling to separate file
xen/gntdev: add VM_PFNMAP to vma
xen/gntdev: allow usermode to map granted pages
xen: define gnttab_set_map_op/unmap_op
Fix up trivial conflict in drivers/xen/Kconfig
When adding a page to m2p_override we change the p2m of the page so we
need to also clear the old pte of the kernel linear mapping because it
doesn't correspond anymore.
When we remove the page from m2p_override we restore the original p2m of
the page and we also restore the old pte of the kernel linear mapping.
Before changing the p2m mappings in m2p_add_override and
m2p_remove_override, check that the page passed as argument is valid and
return an error if it is not.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
In m2p_add_override store the original mfn into page->index and then
change the p2m mapping, setting mfns as FOREIGN_FRAME.
In m2p_remove_override restore the original mapping.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Add a simple hashtable based mechanism to override some portions of the
m2p, so that we can find out the pfn corresponding to an mfn of a
granted page. In fact entries corresponding to granted pages in the m2p
hold the original pfn value of the page in the source domain that
granted it.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'stable/bug-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/event: validate irq before get evtchn by irq
xen/fb: fix potential memory leak
xen/fb: fix xenfb suspend/resume race.
xen: disable ACPI NUMA for PV guests
xen/irq: Cleanup the find_unbound_irq
* 'stable/generic' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: HVM X2APIC support
apic: Move hypervisor detection of x2apic to hypervisor.h
Xen does not currently expose PV-NUMA information to PV
guests. Therefore disable NUMA for the time being to prevent the
kernel picking up on an host-level NUMA information which it might
come across in the firmware.
[ Added comment - Jeremy ]
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This patch is similiar to Gleb Natapov's patch for KVM, which enable the
hypervisor to emulate x2apic feature for the guest. By this way, the emulation
of lapic would be simpler with x2apic interface(MSR), and faster.
[v2: Re-organized 'xen_hvm_need_lapic' per Ian Campbell suggestion]
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Use this_cpu_ops to reduce code size and simplify things in various places.
V3->V4:
Move instance of this_cpu_inc_return to a later patchset so that
this patch can be applied without infrastructure changes.
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86/pvclock: Zero last_value on resume
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf record: Fix eternal wait for stillborn child
perf header: Don't assume there's no attr info if no sample ids is provided
perf symbols: Figure out start address of kernel map from kallsyms
perf symbols: Fix kallsyms kernel/module map splitting
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
nohz: Fix printk_needs_cpu() return value on offline cpus
printk: Fix wake_up_klogd() vs cpu hotplug
* '2.6.37-rc4-pvhvm-fixes' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm:
xen: unplug the emulated devices at resume time
xen: fix save/restore for PV on HVM guests with pirq remapping
xen: resume the pv console for hvm guests too
xen: fix MSI setup and teardown for PV on HVM guests
xen: use PHYSDEVOP_get_free_pirq to implement find_unbound_pirq
* 'upstream/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen: allocate irq descs on any NUMA node
xen: prevent crashes with non-HIGHMEM 32-bit kernels with largeish memory
xen: use default_idle
xen: clean up "extra" memory handling some more
* 'upstream/bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen: x86/32: perform initial startup on initial_page_table
xen: don't bother to stop other cpus on shutdown/reboot
On stock 2.6.37-rc4, running:
# mount lilith:/export /mnt/lilith
# find /mnt/lilith/ -type f -print0 | xargs -0 file
crashes the machine fairly quickly under Xen. Often it results in oops
messages, but the couple of times I tried just now, it just hung quietly
and made Xen print some rude messages:
(XEN) mm.c:2389:d80 Bad type (saw 7400000000000001 != exp
3000000000000000) for mfn 1d7058 (pfn 18fa7)
(XEN) mm.c:964:d80 Attempt to create linear p.t. with write perms
(XEN) mm.c:2389:d80 Bad type (saw 7400000000000010 != exp
1000000000000000) for mfn 1d2e04 (pfn 1d1fb)
(XEN) mm.c:2965:d80 Error while pinning mfn 1d2e04
Which means the domain tried to map a pagetable page RW, which would
allow it to map arbitrary memory, so Xen stopped it. This is because
vm_unmap_ram() left some pages mapped in the vmalloc area after NFS had
finished with them, and those pages got recycled as pagetable pages
while still having these RW aliases.
Removing those mappings immediately removes the Xen-visible aliases, and
so it has no problem with those pages being reused as pagetable pages.
Deferring the TLB flush doesn't upset Xen because it can flush the TLB
itself as needed to maintain its invariants.
When unmapping a region in the vmalloc space, clear the ptes
immediately. There's no point in deferring this because there's no
amortization benefit.
The TLBs are left dirty, and they are flushed lazily to amortize the
cost of the IPIs.
This specific motivation for this patch is an oops-causing regression
since 2.6.36 when using NFS under Xen, triggered by the NFS client's use
of vm_map_ram() introduced in 56e4ebf877 ("NFS: readdir with vmapped
pages") . XFS also uses vm_map_ram() and could cause similar problems.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Bryan Schumaker <bjschuma@netapp.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Alex Elder <aelder@sgi.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Only make swapper_pg_dir readonly and pinned when generic x86 architecture code
(which also starts on initial_page_table) switches to it. This helps ensure
that the generic setup paths work on Xen unmodified. In particular
clone_pgd_range writes directly to the destination pgd entries and is used to
initialise swapper_pg_dir so we need to ensure that it remains writeable until
the last possible moment during bring up.
This is complicated slightly by the need to avoid sharing kernel PMD entries
when running under Xen, therefore the Xen implementation must make a copy of
the kernel PMD (which is otherwise referred to by both intial_page_table and
swapper_pg_dir) before switching to swapper_pg_dir.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Xen will shoot all the VCPUs when we do a shutdown hypercall, so there's
no need to do it manually.
In any case it will fail because all the IPI irqs have been pulled
down by this point, so the cross-CPU calls will simply hang forever.
Until change 76fac077db the function calls
were not synchronously waited for, so this wasn't apparent. However after
that change the calls became synchronous leading to a hang on shutdown
on multi-VCPU guests.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
Cc: Alok Kataria <akataria@vmware.com>
If the guest domain has been suspend/resumed or migrated, then the
system clock backing the pvclock clocksource may revert to a smaller
value (ie, can be non-monotonic across the migration/save-restore).
Make sure we zero last_value in that case so that the domain
continues to see clock updates.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Only make swapper_pg_dir readonly and pinned when generic x86 architecture code
(which also starts on initial_page_table) switches to it. This helps ensure
that the generic setup paths work on Xen unmodified. In particular
clone_pgd_range writes directly to the destination pgd entries and is used to
initialise swapper_pg_dir so we need to ensure that it remains writeable until
the last possible moment during bring up.
This is complicated slightly by the need to avoid sharing kernel PMD entries
when running under Xen, therefore the Xen implementation must make a copy of
the kernel PMD (which is otherwise referred to by both intial_page_table and
swapper_pg_dir) before switching to swapper_pg_dir.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We just need the idle loop to drop into safe_halt, which default_idle()
is perfectly capable of doing. There's no need to duplicate it.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Make sure that extra_pages is added for all E820_RAM regions beyond
mem_end - completely excluded regions as well as the remains of partially
included regions.
Also makes sure the extra region is not unnecessarily high, and simplifies
the logic to decide which regions should be added.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
* upstream/core:
xen/events: Use PIRQ instead of GSI value when unmapping MSI/MSI-X irqs.
xen: set IO permission early (before early_cpu_init())
xen: re-enable boot-time ballooning
xen/balloon: make sure we only include remaining extra ram
xen/balloon: the balloon_lock is useless
xen: add extra pages to balloon
xen/events: use locked set|clear_bit() for cpu_evtchn_mask
xen/evtchn: clear secondary CPUs' cpu_evtchn_mask[] after restore
xen: implement XENMEM_machphys_mapping
* upstream/xenfs:
Revert "xen/privcmd: create address space to allow writable mmaps"
xen/xenfs: update xenfs_mount for new prototype
xen: fix header export to userspace
xen: set vma flag VM_PFNMAP in the privcmd mmap file_op
xen: xenfs: privcmd: check put_user() return code
* upstream/evtchn:
xen: make evtchn's name less generic
xen/evtchn: the evtchn device is non-seekable
xen/evtchn: add missing static
xen/evtchn: Fix name of Xen event-channel device
xen/evtchn: don't do unbind_from_irqhandler under spinlock
xen/evtchn: remove spurious barrier
xen/evtchn: ports start enabled
xen/evtchn: dynamically allocate port_user array
xen/evtchn: track enabled state for each port
This patch is based off "xen dom0: Set up basic IO permissions for dom0."
by Juan Quintela <quintela@redhat.com>.
On AMD machines when we boot the kernel as Domain 0 we get this nasty:
mapping kernel into physical memory
Xen: setup ISA identity maps
about to get started...
(XEN) traps.c:475:d0 Unhandled general protection fault fault/trap [#13] on VCPU 0 [ec=0000]
(XEN) domain_crash_sync called from entry.S
(XEN) Domain 0 (vcpu#0) crashed on cpu#0:
(XEN) ----[ Xen-4.1-101116 x86_64 debug=y Not tainted ]----
(XEN) CPU: 0
(XEN) RIP: e033:[<ffffffff8130271b>]
(XEN) RFLAGS: 0000000000000282 EM: 1 CONTEXT: pv guest
(XEN) rax: 000000008000c068 rbx: ffffffff8186c680 rcx: 0000000000000068
(XEN) rdx: 0000000000000cf8 rsi: 000000000000c000 rdi: 0000000000000000
(XEN) rbp: ffffffff81801e98 rsp: ffffffff81801e50 r8: ffffffff81801eac
(XEN) r9: ffffffff81801ea8 r10: ffffffff81801eb4 r11: 00000000ffffffff
(XEN) r12: ffffffff8186c694 r13: ffffffff81801f90 r14: ffffffffffffffff
(XEN) r15: 0000000000000000 cr0: 000000008005003b cr4: 00000000000006f0
(XEN) cr3: 0000000221803000 cr2: 0000000000000000
(XEN) ds: 0000 es: 0000 fs: 0000 gs: 0000 ss: e02b cs: e033
(XEN) Guest stack trace from rsp=ffffffff81801e50:
RIP points to read_pci_config() function.
The issue is that we don't set IO permissions for the Linux kernel early enough.
The call sequence used to be:
xen_start_kernel()
x86_init.oem.arch_setup = xen_setup_arch;
setup_arch:
- early_cpu_init
- early_init_amd
- read_pci_config
- x86_init.oem.arch_setup [ xen_arch_setup ]
- set IO permissions.
We need to set the IO permissions earlier on, which this patch does.
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Now that the balloon driver doesn't stumble over non-RAM pages, we
can enable the extra space for ballooning.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
* commit 'v2.6.37-rc2': (10093 commits)
Linux 2.6.37-rc2
capabilities/syslog: open code cap_syslog logic to fix build failure
i2c: Sanity checks on adapter registration
i2c: Mark i2c_adapter.id as deprecated
i2c: Drivers shouldn't include <linux/i2c-id.h>
i2c: Delete unused adapter IDs
i2c: Remove obsolete cleanup for clientdata
include/linux/kernel.h: Move logging bits to include/linux/printk.h
Fix gcc 4.5.1 miscompiling drivers/char/i8k.c (again)
hwmon: (w83795) Check for BEEP pin availability
hwmon: (w83795) Clear intrusion alarm immediately
hwmon: (w83795) Read the intrusion state properly
hwmon: (w83795) Print the actual temperature channels as sources
hwmon: (w83795) List all usable temperature sources
hwmon: (w83795) Expose fan control method
hwmon: (w83795) Fix fan control mode attributes
hwmon: (lm95241) Check validity of input values
hwmon: Change mail address of Hans J. Koch
PCI: sysfs: fix printk warnings
GFS2: Fix inode deallocation race
...
This hypercall allows Xen to specify a non-default location for the
machine to physical mapping. This capability is used when running a 32
bit domain 0 on a 64 bit hypervisor to shrink the hypervisor hole to
exactly the size required.
[ Impact: add Xen hypercall definitions ]
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Set VM_PFNMAP in the privcmd mmap file_op, rather than later in
xen_remap_domain_mfn_range when it is too late because
vma_wants_writenotify has already been called and vm_page_prot has
already been modified.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
We already deliberately setup a 1-1 P2M for the region up to 1M in
order to allow code which assumes this region is already mapped to
work without having to convert everything to ioremap.
Domain 0 should not return any apparently unused memory regions
(reserved or otherwise) in this region to Xen since the e820 may not
accurately reflect what the BIOS has stashed in this region.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
sizeof(pmd_t *) is 4 bytes on 32-bit PAE leading to an allocation of
only 2048 bytes. The correct size is sizeof(pmd_t) giving us a full
page allocation.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
and branch 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm
* 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm:
xen: register xen pci notifier
xen: initialize cpu masks for pv guests in xen_smp_init
xen: add a missing #include to arch/x86/pci/xen.c
xen: mask the MTRR feature from the cpuid
xen: make hvc_xen console work for dom0.
xen: add the direct mapping area for ISA bus access
xen: Initialize xenbus for dom0.
xen: use vcpu_ops to setup cpu masks
xen: map a dummy page for local apic and ioapic in xen_set_fixmap
xen: remap MSIs into pirqs when running as initial domain
xen: remap GSIs as pirqs when running as initial domain
xen: introduce XEN_DOM0 as a silent option
xen: map MSIs into pirqs
xen: support GSI -> pirq remapping in PV on HVM guests
xen: add xen hvm acpi_register_gsi variant
acpi: use indirect call to register gsi in different modes
xen: implement xen_hvm_register_pirq
xen: get the maximum number of pirqs from xen
xen: support pirq != irq
* 'stable/xen-pcifront-0.8.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (27 commits)
X86/PCI: Remove the dependency on isapnp_disable.
xen: Update Makefile with CONFIG_BLOCK dependency for biomerge.c
MAINTAINERS: Add myself to the Xen Hypervisor Interface and remove Chris Wright.
x86: xen: Sanitse irq handling (part two)
swiotlb-xen: On x86-32 builts, select SWIOTLB instead of depending on it.
MAINTAINERS: Add myself for Xen PCI and Xen SWIOTLB maintainer.
xen/pci: Request ACS when Xen-SWIOTLB is activated.
xen-pcifront: Xen PCI frontend driver.
xenbus: prevent warnings on unhandled enumeration values
xenbus: Xen paravirtualised PCI hotplug support.
xen/x86/PCI: Add support for the Xen PCI subsystem
x86: Introduce x86_msi_ops
msi: Introduce default_[teardown|setup]_msi_irqs with fallback.
x86/PCI: Export pci_walk_bus function.
x86/PCI: make sure _PAGE_IOMAP it set on pci mappings
x86/PCI: Clean up pci_cache_line_size
xen: fix shared irq device passthrough
xen: Provide a variant of xen_poll_irq with timeout.
xen: Find an unbound irq number in reverse order (high to low).
xen: statically initialize cpu_evtchn_mask_p
...
Fix up trivial conflicts in drivers/pci/Makefile
* akpm-incoming-2: (139 commits)
epoll: make epoll_wait() use the hrtimer range feature
select: rename estimate_accuracy() to select_estimate_accuracy()
Remove duplicate includes from many files
ramoops: use the platform data structure instead of module params
kernel/resource.c: handle reinsertion of an already-inserted resource
kfifo: fix kfifo_alloc() to return a signed int value
w1: don't allow arbitrary users to remove w1 devices
alpha: remove dma64_addr_t usage
mips: remove dma64_addr_t usage
sparc: remove dma64_addr_t usage
fuse: use release_pages()
taskstats: use real microsecond granularity for CPU times
taskstats: split fill_pid function
taskstats: separate taskstats commands
delayacct: align to 8 byte boundary on 64-bit systems
delay-accounting: reimplement -c for getdelays.c to report information on a target command
namespaces Kconfig: move namespace menu location after the cgroup
namespaces Kconfig: remove the cgroup device whitelist experimental tag
namespaces Kconfig: remove pointless cgroup dependency
namespaces Kconfig: make namespace a submenu
...
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
percpu: Remove the multi-page alignment facility
x86-32: Allocate irq stacks seperate from percpu area
x86-32, mm: Remove duplicated #include
x86, printk: Get rid of <0> from stack output
x86, kexec: Make sure to stop all CPUs before exiting the kernel
x86/vsmp: Eliminate kconfig dependency warning
* 'upstream/xenfs' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen/privcmd: make privcmd visible in domU
xen/privcmd: move remap_domain_mfn_range() to core xen code and export.
privcmd: MMAPBATCH: Fix error handling/reporting
xenbus: export xen_store_interface for xenfs
xen/privcmd: make sure vma is ours before doing anything to it
xen/privcmd: print SIGBUS faults
xen/xenfs: set_page_dirty is supposed to return true if it dirties
xen/privcmd: create address space to allow writable mmaps
xen: add privcmd driver
xen: add variable hypercall caller
xen: add xen_set_domain_pte()
xen: add /proc/xen/xsd_{kva,port} to xenfs
* 'upstream/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen: (29 commits)
xen: include xen/xen.h for definition of xen_initial_domain()
xen: use host E820 map for dom0
xen: correctly rebuild mfn list list after migration.
xen: improvements to VIRQ_DEBUG output
xen: set up IRQ before binding virq to evtchn
xen: ensure that all event channels start off bound to VCPU 0
xen/hvc: only notify if we actually sent something
xen: don't add extra_pages for RAM after mem_end
xen: add support for PAT
xen: make sure xen_max_p2m_pfn is up to date
xen: limit extra memory to a certain ratio of base
xen: add extra pages for E820 RAM regions, even if beyond mem_end
xen: make sure xen_extra_mem_start is beyond all non-RAM e820
xen: implement "extra" memory to reserve space for pages not present at boot
xen: Use host-provided E820 map
xen: don't map missing memory
xen: defer building p2m mfn structures until kernel is mapped
xen: add return value to set_phys_to_machine()
xen: convert p2m to a 3 level tree
xen: make install_p2mtop_page() static
...
Fix up trivial conflict in arch/x86/xen/mmu.c, and fix the use of
'reserve_early()' - in the new memblock world order it is now
'memblock_x86_reserve_range()' instead. Pointed out by Jeremy.
Pv guests don't have ACPI and need the cpu masks to be set
correctly as early as possible so we call xen_fill_possible_map from
xen_smp_init.
On the other hand the initial domain supports ACPI so in this case we skip
xen_fill_possible_map and rely on it. However Xen might limit the number
of cpus usable by the domain, so we filter those masks during smp
initialization using the VCPUOP_is_up hypercall.
It is important that the filtering is done before
xen_setup_vcpu_info_placement.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
CC arch/x86/xen/setup.o
arch/x86/xen/setup.c: In function 'xen_memory_setup':
arch/x86/xen/setup.c:161: error: implicit declaration of function 'xen_initial_domain'
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
We don't want Linux to think that the cpu supports MTRRs when running
under Xen because MTRR operations could only be performed through
hypercalls.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
add the direct mapping area for ISA bus access when running as initial
domain
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Add XEN_DOM0 to arch/x86/xen/Kconfig as a silent compile time option
that gets enabled when xen and basic x86, acpi and pci support are
selected.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When running as initial domain, get the real physical memory map from
xen using the XENMEM_machine_memory_map hypercall and use it to setup
the e820 regions.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Otherwise the second migration attempt fails because the mfn_list_list
still refers to all the old mfns.
We need to update the entires in both p2m_top_mfn and the mid_mfn
pages which p2m_top_mfn refers to.
In order to do this we need to keep track of the virtual addresses
mapping the p2m_mid_mfn pages since we cannot rely on
mfn_to_virt(p2m_top_mfn[idx]) since p2m_top_mfn[idx] will still
contain the old MFN after a migration, which may now belong to another
domain and hence have a different mapping in the m2p.
Therefore add and maintain a third top level page, p2m_top_mfn_p[],
which tracks the virtual addresses of the mfns contained in
p2m_top_mfn[].
We also need to update the content of the p2m_mid_missing_mfn page on
resume to refer to the page's new mfn.
p2m_missing does not need updating since the migration process takes
care of the leaf p2m pages for us.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
If an E820 region is entirely beyond mem_end, don't attempt to truncate
it and add the truncated pages to extra_pages, as they will be negative.
Also, make sure the extra memory region starts after all BIOS provided
E820 regions (and in the case of RAM regions, post-clipping).
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Convert Linux PAT entries into Xen ones when constructing ptes. Linux
doesn't use _PAGE_PAT for ptes, so the only difference in the first 4
entries is that Linux uses _PAGE_PWT for WC, whereas Xen (and default)
use it for WT.
xen_pte_val does the inverse conversion.
We hard-code assumptions about Linux's current PAT layout, but a
warning on the wrmsr to MSR_IA32_CR_PAT should point out any problems.
If necessary we could go to a more general table-based conversion between
Linux and Xen PAT entries.
hugetlbfs poses a problem at the moment, the x86 architecture uses the
same flag for _PAGE_PAT and _PAGE_PSE, which changes meaning depending
on which pagetable level we're using. At the moment this should be OK
so long as nobody tries to do a pte_val on a hugetlbfs pte.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Keep xen_max_p2m_pfn up to date with the end of the extra memory
we're adding. It is possible that it will be too high since memory
may be truncated by a "mem=" option on the kernel command line, but
that won't matter.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
If extra memory is very much larger than the base memory size
then all of the base memory can be filled with structures reserved to
describe the extra memory, leaving no space for anything else.
Even at the maximum ratio there will be little space for anything else,
but this change is intended to at least allow the system to boot rather
than crash mysteriously.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
If an entire E820 RAM region is beyond mem_end, still add its
pages to the extra area so that space can be used by the kernel.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
If Xen gives us non-RAM E820 entries (dom0 only, typically), then
make sure the extra RAM region is beyond them. It's OK for
the extra space to grow into E820 regions, however.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
When using the e820 map to get the initial pseudo-physical address space,
look for either Xen-provided memory which doesn't lie within an E820
region, or an E820 RAM region which extends beyond the Xen-provided
memory range.
Count these pages, and add them to a new "extra memory" range. This range
has an E820 RAM range to describe it - so the kernel will allocate page
structures for it - but it is also marked reserved so that the kernel
will not attempt to use it.
The balloon driver can then add this range as a set of currently
ballooned-out pages, which can be used to extend the domain beyond its
original size.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Rather than simply using a flat memory map from Xen, use its provided
E820 map. This allows the domain builder to tell the domain to reserve
space for more pages than those initially provided at domain-build time.
It also allows the host to specify holes in the address space (for
PCI-passthrough, for example).
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
When setting up a pte for a missing pfn (no matching mfn), just create
an empty pte rather than a junk mapping.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
When building mfn parts of p2m structure, we rely on being able to
use mfn_to_virt, which in turn requires kernel to be mapped into
the linear area (which is distinct from the kernel image mapping
on 64-bit). Defer calling xen_build_mfn_list_list() until after
xen_setup_kernel_pagetable();
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
set_phys_to_machine() can return false on failure, which means a memory
allocation failure for the p2m structure. It can only fail if setting
the mfn for a pfn in previously unused address space. It is guaranteed
to succeed if you're setting a mapping to INVALID_P2M_ENTRY or updating
the mfn for an existing pfn.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Make the p2m structure a 3 level tree which covers the full possible
physical space.
The p2m structure contains mappings from the domain's pfns to system-wide
mfns. The structure has 3 levels and two roots. The first root is for
the domain's own use, and is linked with virtual addresses. The second
is all mfn references, and is used by Xen on save/restore to allow it to
update the p2m mapping for the domain.
At boot, the domain builder provides a simple flat p2m array for all the
initially present pages. We construct the two levels above that using
the early_brk allocator. After early boot time, set_phys_to_machine()
will allocate any missing levels using the normal kernel allocator
(at GFP_KERNEL, so it must be called in a normal blocking context).
Because the early_brk() API requires us to pre-reserve the maximum amount
of memory we could allocate, there is still a CONFIG_XEN_MAX_DOMAIN_MEMORY
config option, but its only negative side-effect is to increase the
kernel's apparent bss size. However, since all unused brk memory is
returned to the heap, there's no real downside to making it large.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Allocate p2m tables based on the actual runtime maximum pfn rather than
the static config-time limit.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Use early brk mechanism to allocate p2m tables, to save memory when
booting non-Xen.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
vfs: make no_llseek the default
vfs: don't use BKL in default_llseek
llseek: automatically add .llseek fop
libfs: use generic_file_llseek for simple_attr
mac80211: disallow seeks in minstrel debug code
lirc: make chardev nonseekable
viotape: use noop_llseek
raw: use explicit llseek file operations
ibmasmfs: use generic_file_llseek
spufs: use llseek in all file operations
arm/omap: use generic_file_llseek in iommu_debug
lkdtm: use generic_file_llseek in debugfs
net/wireless: use generic_file_llseek in debugfs
drm: use noop_llseek
* 'core-memblock-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (74 commits)
x86-64: Only set max_pfn_mapped to 512 MiB if we enter via head_64.S
xen: Cope with unmapped pages when initializing kernel pagetable
memblock, bootmem: Round pfn properly for memory and reserved regions
memblock: Annotate memblock functions with __init_memblock
memblock: Allow memblock_init to be called early
memblock/arm: Fix memblock_region_is_memory() typo
x86, memblock: Remove __memblock_x86_find_in_range_size()
memblock: Fix wraparound in find_region()
x86-32, memblock: Make add_highpages honor early reserved ranges
x86, memblock: Fix crashkernel allocation
arm, memblock: Fix the sparsemem build
memblock: Fix section mismatch warnings
powerpc, memblock: Fix memblock API change fallout
memblock, microblaze: Fix memblock API change fallout
x86: Remove old bootmem code
x86, memblock: Use memblock_memory_size()/memblock_free_memory_size() to get correct dma_reserve
x86: Remove not used early_res code
x86, memblock: Replace e820_/_early string with memblock_
x86: Use memblock to replace early_res
x86, memblock: Use memblock_debug to control debug message print out
...
Fix up trivial conflicts in arch/x86/kernel/setup.c and kernel/Makefile
* git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-irqflags:
Fix IRQ flag handling naming
MIPS: Add missing #inclusions of <linux/irq.h>
smc91x: Add missing #inclusion of <linux/irq.h>
Drop a couple of unnecessary asm/system.h inclusions
SH: Add missing consts to sys_execve() declaration
Blackfin: Rename IRQ flags handling functions
Blackfin: Add missing dep to asm/irqflags.h
Blackfin: Rename DES PC2() symbol to avoid collision
Blackfin: Split the BF532 BFIN_*_FIO_FLAG() functions to their own header
Blackfin: Split PLL code from mach-specific cdef headers
* 'x86-vmware-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, paravirt: Remove alloc_pmd_clone hook, only used by VMI
x86, vmware: Remove deprecated VMI kernel support
Fix up trivial #include conflict in arch/x86/kernel/smpboot.c
x86 smp_ops now has a new op, stop_other_cpus which takes a parameter
"wait" this allows the caller to specify if it wants to stop until all
the cpus have processed the stop IPI. This is required specifically
for the kexec case where we should wait for all the cpus to be stopped
before starting the new kernel. We now wait for the cpus to stop in
all cases except for panic/kdump where we expect things to be broken
and we are doing our best to make things work anyway.
This patch fixes a legitimate regression, which was introduced during
2.6.30, by commit id 4ef702c10b.
Signed-off-by: Alok N Kataria <akataria@vmware.com>
LKML-Reference: <1286833028.1372.20.camel@ank32.eng.vmware.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: <stable@kernel.org> v2.6.30-36
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This allows xenfs to be built as a module, previously it required flush_tlb_all
and arbitrary_virt_to_machine to be exported.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Add xen_set_domain_pte() to allow setting a pte mapping a page from
another domain. The common case is to map from DOMID_IO, the pseudo
domain which owns all IO pages, but will also be used in the privcmd
interface to map other domain pages.
[ Impact: new Xen-internal API for cross-domain mappings ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
It used to done in the Xen startup code but that is not really
appropiate.
[v2: Update Kconfig with PCI requirement]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The frontend stub lives in arch/x86/pci/xen.c, alongside other
sub-arch PCI init code (e.g. olpc.c).
It provides a mechanism for Xen PCI frontend to setup/destroy
legacy interrupts, MSI/MSI-X, and PCI configuration operations.
[ Impact: add core of Xen PCI support ]
[ v2: Removed the IOMMU code and only focusing on PCI.]
[ v3: removed usage of pci_scan_all_fns as that does not exist]
[ v4: introduced pci_xen value to fix compile warnings]
[ v5: squished fixes+features in one patch, changed Reviewed-by to Ccs]
[ v7: added Acked-by]
Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Qing He <qing.he@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
If a guest domain wants to access PCI devices through the frontend
driver (coming later in the patch series), it will need access to the
I/O space.
[ Impact: Allow for domU IO access, preparing for pci passthrough ]
Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.
The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.
New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.
The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.
Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.
Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.
===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}
@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}
@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};
@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};
@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};
@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};
@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};
// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};
@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};
// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};
// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};
// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};
@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};
// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////
@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};
@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};
@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};
@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Xen requires that all pages containing pagetable entries to be mapped
read-only. If pages used for the initial pagetable are already mapped
then we can change the mapping to RO. However, if they are initially
unmapped, we need to make sure that when they are later mapped, they
are also mapped RO.
We do this by knowing that the kernel pagetable memory is pre-allocated
in the range e820_table_start - e820_table_end, so any pfn within this
range should be mapped read-only. However, the pagetable setup code
early_ioremaps the pages to write their entries, so we must make sure
that mappings created in the early_ioremap fixmap area are mapped RW.
(Those mappings are removed before the pages are presented to Xen
as pagetable pages.)
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
LKML-Reference: <4CB63A80.8060702@goop.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The Xen setup code needs to call memblock_x86_reserve_range() very early,
so allow it to initialize the memblock subsystem before doing so. The
second memblock_init() is ignored.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
LKML-Reference: <4CACFDAD.3090900@goop.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Fix the IRQ flag handling naming. In linux/irqflags.h under one configuration,
it maps:
local_irq_enable() -> raw_local_irq_enable()
local_irq_disable() -> raw_local_irq_disable()
local_irq_save() -> raw_local_irq_save()
...
and under the other configuration, it maps:
raw_local_irq_enable() -> local_irq_enable()
raw_local_irq_disable() -> local_irq_disable()
raw_local_irq_save() -> local_irq_save()
...
This is quite confusing. There should be one set of names expected of the
arch, and this should be wrapped to give another set of names that are expected
by users of this facility.
Change this to have the arch provide:
flags = arch_local_save_flags()
flags = arch_local_irq_save()
arch_local_irq_restore(flags)
arch_local_irq_disable()
arch_local_irq_enable()
arch_irqs_disabled_flags(flags)
arch_irqs_disabled()
arch_safe_halt()
Then linux/irqflags.h wraps these to provide:
raw_local_save_flags(flags)
raw_local_irq_save(flags)
raw_local_irq_restore(flags)
raw_local_irq_disable()
raw_local_irq_enable()
raw_irqs_disabled_flags(flags)
raw_irqs_disabled()
raw_safe_halt()
with type checking on the flags 'arguments', and then wraps those to provide:
local_save_flags(flags)
local_irq_save(flags)
local_irq_restore(flags)
local_irq_disable()
local_irq_enable()
irqs_disabled_flags(flags)
irqs_disabled()
safe_halt()
with tracing included if enabled.
The arch functions can now all be inline functions rather than some of them
having to be macros.
Signed-off-by: David Howells <dhowells@redhat.com> [X86, FRV, MN10300]
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> [Tile]
Signed-off-by: Michal Simek <monstr@monstr.eu> [Microblaze]
Tested-by: Catalin Marinas <catalin.marinas@arm.com> [ARM]
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> [AVR]
Acked-by: Tony Luck <tony.luck@intel.com> [IA-64]
Acked-by: Hirokazu Takata <takata@linux-m32r.org> [M32R]
Acked-by: Greg Ungerer <gerg@uclinux.org> [M68K/M68KNOMMU]
Acked-by: Ralf Baechle <ralf@linux-mips.org> [MIPS]
Acked-by: Kyle McMartin <kyle@mcmartin.ca> [PA-RISC]
Acked-by: Paul Mackerras <paulus@samba.org> [PowerPC]
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [S390]
Acked-by: Chen Liqin <liqin.chen@sunplusct.com> [Score]
Acked-by: Matt Fleming <matt@console-pimps.org> [SH]
Acked-by: David S. Miller <davem@davemloft.net> [Sparc]
Acked-by: Chris Zankel <chris@zankel.net> [Xtensa]
Reviewed-by: Richard Henderson <rth@twiddle.net> [Alpha]
Reviewed-by: Yoshinori Sato <ysato@users.sourceforge.jp> [H8300]
Cc: starvik@axis.com [CRIS]
Cc: jesper.nilsson@axis.com [CRIS]
Cc: linux-cris-kernel@axis.com
if !xen_have_vector_callback do not initialize PV timer unconditionally
because we still don't know how many cpus are available and if there is
more than one we won't be able to receive the timer interrupts on
cpu > 0.
This patch fixes an hang at boot when Xen does not support vector
callbacks and the guest has multiple vcpus.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
1.include linux/memblock.h directly. so later could reduce e820.h reference.
2 this patch is done by sed scripts mainly
-v2: use MEMBLOCK_ERROR instead of -1ULL or -1UL
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
We utilize the IOMMU_INIT macros to create this dependency:
[null]
|
[pci_xen_swiotlb_detect]
|
[pci_swiotlb_detect_override]
|
[pci_swiotlb_detect_4gb]
In other words, we set 'pci_xen_swiotlb_detect' to be
the first detection to be run during start.
CC: Fujita Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
LKML-Reference: <1282845485-8991-7-git-send-email-konrad.wilk@oracle.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
VMI was the only user of the alloc_pmd_clone hook, given that VMI
is now removed we can also remove this hook.
Signed-off-by: Alok N Kataria <akataria@vmware.com>
LKML-Reference: <1282608357.19396.36.camel@ank32.eng.vmware.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
It is not immediately clear what this option causes to become
ignored. The actual meaning is that it is not necessary to unplug the
emulated devices to safely use the PV ones, even if the platform does
not support the unplug protocol. (pressumably the user will only add
this option if they have ensured that their domain configuration is
safe).
I think xen_emul_unplug=unnecessary better captures this.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>
this allows the user to disable pvhvm and revert to emulated devices
in case of a system misconfiguration (e.g. initramfs with only
emulated drivers in it).
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>
* 'stable/xen-swiotlb-0.8.6' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
x86: Detect whether we should use Xen SWIOTLB.
pci-swiotlb-xen: Add glue code to setup dma_ops utilizing xen_swiotlb_* functions.
swiotlb-xen: SWIOTLB library for Xen PV guest with PCI passthrough.
xen/mmu: inhibit vmap aliases rather than trying to clear them out
vmap: add flag to allow lazy unmap to be disabled at runtime
xen: Add xen_create_contiguous_region
xen: Rename the balloon lock
xen: Allow unprivileged Xen domains to create iomap pages
xen: use _PAGE_IOMAP in ioremap to do machine mappings
Fix up trivial conflicts (adding both xen swiotlb and xen pci platform
driver setup close to each other) in drivers/xen/{Kconfig,Makefile} and
include/xen/xen-ops.h
* upstream/pvhvm:
Introduce CONFIG_XEN_PVHVM compile option
blkfront: do not create a PV cdrom device if xen_hvm_guest
support multiple .discard.* sections to avoid section type conflicts
xen/pvhvm: fix build problem when !CONFIG_XEN
xenfs: enable for HVM domains too
x86: Call HVMOP_pagetable_dying on exit_mmap.
x86: Unplug emulated disks and nics.
x86: Use xen_vcpuop_clockevent, xen_clocksource and xen wallclock.
xen: Fix find_unbound_irq in presence of ioapic irqs.
xen: Add suspend/resume support for PV on HVM guests.
xen: Xen PCI platform device driver.
x86/xen: event channels delivery on HVM.
x86: early PV on HVM features initialization.
xen: Add support for HVM hypercalls.
Conflicts:
arch/x86/xen/enlighten.c
arch/x86/xen/time.c
* upstream/core:
xen/panic: use xen_reboot and fix smp_send_stop
Xen: register panic notifier to take crashes of xen guests on panic
xen: support large numbers of CPUs with vcpu info placement
xen: drop xen_sched_clock in favour of using plain wallclock time
pvops: do not notify callers from register_xenstore_notifier
xen: make sure pages are really part of domain before freeing
xen: release unused free memory
Offline vcpu when using stop_self.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Register a panic notifier so that when the guest crashes it can shut
down the domain and indicate it was a crash to the host.
Signed-off-by: Donald Dutile <ddutile@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
When vcpu info placement is supported, we're not limited to MAX_VIRT_CPUS
vcpus. However, if it isn't supported, then ignore any excess vcpus.
Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
xen_sched_clock only counts unstolen time. In principle this should
be useful to the Linux scheduler so that it knows how much time a process
actually consumed. But in practice this doesn't work very well as the
scheduler expects the sched_clock time to be synchronized between
cpus. It also uses sched_clock to measure the time a task spends
sleeping, in which case "unstolen time" isn't meaningful.
So just use plain xen_clocksource_read to return wallclock nanoseconds
for sched_clock.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
This patch introduce a CONFIG_XEN_PVHVM compile time option to
enable/disable Xen PV on HVM support.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
David Vrabel