Commit Graph

3002 Commits

Author SHA1 Message Date
Steven Rostedt 228bdaa95f x86: Keep current stack in NMI breakpoints
We want to allow NMI handlers to have breakpoints to be able to
remove stop_machine from ftrace, kprobes and jump_labels. But if
an NMI interrupts a current breakpoint, and then it triggers a
breakpoint itself, it will switch to the breakpoint stack and
corrupt the data on it for the breakpoint processing that it
interrupted.

Instead, have the NMI check if it interrupted breakpoint processing
by checking if the stack that is currently used is a breakpoint
stack. If it is, then load a special IDT that changes the IST
for the debug exception to keep the same stack in kernel context.
When the NMI is done, it puts it back.

This way, if the NMI does trigger a breakpoint, it will keep
using the same stack and not stomp on the breakpoint data for
the breakpoint it interrupted.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-12-21 15:38:55 -05:00
Matt Fleming e8c7106280 x86, efi: Calling __pa() with an ioremap()ed address is invalid
If we encounter an efi_memory_desc_t without EFI_MEMORY_WB set
in ->attribute we currently call set_memory_uc(), which in turn
calls __pa() on a potentially ioremap'd address.

On CONFIG_X86_32 this is invalid, resulting in the following
oops on some machines:

  BUG: unable to handle kernel paging request at f7f22280
  IP: [<c10257b9>] reserve_ram_pages_type+0x89/0x210
  [...]

  Call Trace:
   [<c104f8ca>] ? page_is_ram+0x1a/0x40
   [<c1025aff>] reserve_memtype+0xdf/0x2f0
   [<c1024dc9>] set_memory_uc+0x49/0xa0
   [<c19334d0>] efi_enter_virtual_mode+0x1c2/0x3aa
   [<c19216d4>] start_kernel+0x291/0x2f2
   [<c19211c7>] ? loglevel+0x1b/0x1b
   [<c19210bf>] i386_start_kernel+0xbf/0xc8

A better approach to this problem is to map the memory region
with the correct attributes from the start, instead of modifying
it after the fact. The uncached case can be handled by
ioremap_nocache() and the cached by ioremap_cache().

Despite first impressions, it's not possible to use
ioremap_cache() to map all cached memory regions on
CONFIG_X86_64 because EFI_RUNTIME_SERVICES_DATA regions really
don't like being mapped into the vmalloc space, as detailed in
the following bug report,

	https://bugzilla.redhat.com/show_bug.cgi?id=748516

Therefore, we need to ensure that any EFI_RUNTIME_SERVICES_DATA
regions are covered by the direct kernel mapping table on
CONFIG_X86_64. To accomplish this we now map E820_RESERVED_EFI
regions via the direct kernel mapping with the initial call to
init_memory_mapping() in setup_arch(), whereas previously these
regions wouldn't be mapped if they were after the last E820_RAM
region until efi_ioremap() was called. Doing it this way allows
us to delete efi_ioremap() completely.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Huang Ying <huang.ying.caritas@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1321621751-3650-1-git-send-email-matt@console-pimps.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-09 08:32:26 +01:00
Linus Torvalds 45e713efe2 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  intr_remapping: Fix section mismatch in ir_dev_scope_init()
  intel-iommu: Fix section mismatch in dmar_parse_rmrr_atsr_dev()
  x86, amd: Fix up numa_node information for AMD CPU family 15h model 0-0fh northbridge functions
  x86, AMD: Correct align_va_addr documentation
  x86/rtc, mrst: Don't register a platform RTC device for for Intel MID platforms
  x86/mrst: Battery fixes
  x86/paravirt: PTE updates in k(un)map_atomic need to be synchronous, regardless of lazy_mmu mode
  x86: Fix "Acer Aspire 1" reboot hang
  x86/mtrr: Resolve inconsistency with Intel processor manual
  x86: Document rdmsr_safe restrictions
  x86, microcode: Fix the failure path of microcode update driver init code
  Add TAINT_FIRMWARE_WORKAROUND on MTRR fixup
  x86/mpparse: Account for bus types other than ISA and PCI
  x86, mrst: Change the pmic_gpio device type to IPC
  mrst: Added some platform data for the SFI translations
  x86,mrst: Power control commands update
  x86/reboot: Blacklist Dell OptiPlex 990 known to require PCI reboot
  x86, UV: Fix UV2 hub part number
  x86: Add user_mode_vm check in stack_overflow_check
2011-12-05 16:54:15 -08:00
Linus Torvalds 7125faceab Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched, x86: Avoid unnecessary overflow in sched_clock
  sched: Fix buglet in return_cfs_rq_runtime()
  sched: Avoid SMT siblings in select_idle_sibling() if possible
  sched: Set the command name of the idle tasks in SMP kernels
  sched, rt: Provide means of disabling cross-cpu bandwidth sharing
  sched: Document wait_for_completion_*() return values
  sched_fair: Fix a typo in the comment describing update_sd_lb_stats
  sched: Add a comment to effective_load() since it's a pain
2011-12-05 16:50:24 -08:00
Mathias Nyman 35d4769962 x86/rtc, mrst: Don't register a platform RTC device for for Intel MID platforms
Intel MID x86 platforms have a memory mapped virtual RTC
instead.  No MID platform have the default ports (and
accessing them may do weird stuff).

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: feng.tang@intel.com
Cc: Feng Tang <feng.tang@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05 17:09:21 +01:00
Ingo Molnar f1b23714cb Merge branch 'ucode' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp into x86/urgent 2011-12-05 16:38:51 +01:00
Borislav Petkov ce37defc0f x86: Document rdmsr_safe restrictions
Recently, I got bitten by using rdmsr_safe too early in the boot
process. Document its shortcomings for future reference.

Link: http://lkml.kernel.org/r/4ED5B70F.606@lwfinger.net
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
2011-12-05 14:28:37 +01:00
Jacob Pan 48bc556210 x86,mrst: Power control commands update
On the Intel MID devices SCU commands are issued to manage power
off and the like. We need to issue different ones for
non-Lincroft based devices.

Signed-off-by: Alek Du <alek.du@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05 12:42:11 +01:00
Jack Steiner b495e039b4 x86, UV: Fix UV2 hub part number
There was a mixup when the SGI UV2 hub chip was sent to be
fabricated, and it ended up with the wrong part number in the
HRP_NODE_ID mmr. Future versions of the chip will (may) have the
correct part number. Change the UV infrastructure to recognize
both part numbers as valid IDs of a UV2 hub chip.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Link: http://lkml.kernel.org/r/20111129210058.GA20452@sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05 11:49:52 +01:00
Konrad Rzeszutek Wilk e5fd47bfab xen/pm_idle: Make pm_idle be default_idle under Xen.
The idea behind commit d91ee5863b ("cpuidle: replace xen access to x86
pm_idle and default_idle") was to have one call - disable_cpuidle()
which would make pm_idle not be molested by other code.  It disallows
cpuidle_idle_call to be set to pm_idle (which is excellent).

But in the select_idle_routine() and idle_setup(), the pm_idle can still
be set to either: amd_e400_idle, mwait_idle or default_idle.  This
depends on some CPU flags (MWAIT) and in AMD case on the type of CPU.

In case of mwait_idle we can hit some instances where the hypervisor
(Amazon EC2 specifically) sets the MWAIT and we get:

  Brought up 2 CPUs
  invalid opcode: 0000 [#1] SMP

  Pid: 0, comm: swapper Not tainted 3.1.0-0.rc6.git0.3.fc16.x86_64 #1
  RIP: e030:[<ffffffff81015d1d>]  [<ffffffff81015d1d>] mwait_idle+0x6f/0xb4
  ...
  Call Trace:
   [<ffffffff8100e2ed>] cpu_idle+0xae/0xe8
   [<ffffffff8149ee78>] cpu_bringup_and_idle+0xe/0x10
  RIP  [<ffffffff81015d1d>] mwait_idle+0x6f/0xb4
   RSP <ffff8801d28ddf10>

In the case of amd_e400_idle we don't get so spectacular crashes, but we
do end up making an MSR which is trapped in the hypervisor, and then
follow it up with a yield hypercall.  Meaning we end up going to
hypervisor twice instead of just once.

The previous behavior before v3.0 was that pm_idle was set to
default_idle regardless of select_idle_routine/idle_setup.

We want to do that, but only for one specific case: Xen.  This patch
does that.

Fixes RH BZ #739499 and Ubuntu #881076
Reported-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-03 10:49:58 -08:00
Salman Qazi 4cecf6d401 sched, x86: Avoid unnecessary overflow in sched_clock
(Added the missing signed-off-by line)

In hundreds of days, the __cycles_2_ns calculation in sched_clock
has an overflow.  cyc * per_cpu(cyc2ns, cpu) exceeds 64 bits, causing
the final value to become zero.  We can solve this without losing
any precision.

We can decompose TSC into quotient and remainder of division by the
scale factor, and then use this to convert TSC into nanoseconds.

Signed-off-by: Salman Qazi <sqazi@google.com>
Acked-by: John Stultz <johnstul@us.ibm.com>
Reviewed-by: Paul Turner <pjt@google.com>
Cc: stable@kernel.org
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20111115221121.7262.88871.stgit@dungbeetle.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-16 19:51:25 +01:00
Jacob Pan 064a59b6dd x86/mrst: Avoid reporting wrong nmi status
Moorestown/Medfield platform does not have port 0x61 to report
NMI status, nor does it have external NMI sources. The only NMI
sources are from lapic, as results of perf counter overflow or
IPI, e.g. NMI watchdog or spin lock debug.

Reading port 0x61 on Moorestown will return 0xff which misled
NMI handlers to false critical errors such memory parity error.
The subsequent ioport access for NMI handling can also cause
undefined behavior on Moorestown.

This patch allows kernel process NMI due to watchdog or backrace
dump without unnecessary hangs.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
[hand applied]
Signed-off-by: Alan Cox <alan@linux.intel.com>
2011-11-10 16:21:01 +01:00
Dirk Brandewie 0a9153261d x86/mrst: Add support for Penwell clock calibration
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-10 16:20:59 +01:00
Jacob Pan 1ade93efd0 x86/apic: Allow use of lapic timer early calibration result
lapic timer calibration can be combined with tsc in platform
specific calibration functions. if such calibration result is
obtained early, we can skip the redundant calibration loops.

Signed-off-by: Jacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-10 16:20:57 +01:00
Feng Tang cf8ff6b6ab x86/platform: Add a wallclock_init func to x86_platforms ops
Some wall clock devices use MMIO based HW register, this new
function will give them a chance to do some initialization work
before their get/set_time service get called.

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-10 16:20:53 +01:00
Luck, Tony 66f5ddf30a x86/mce: Make mce_chrdev_ops 'static const'
Arjan would like to make struct file_operations const, but
mce-inject directly writes to the mce_chrdev_ops to install its
write handler. In an ideal world mce-inject would have its own
character device, but we have a sizable legacy of test scripts
that hardwire "/dev/mcelog", so it would be painful to switch to
a separate device now. Instead, this patch switches to a stub
function in the mce code, with a registration helper that
mce-inject can call when it is loaded.

Note that this would also allow for a sane process to allow
mce-inject to be unloaded again (with an unregister function,
and appropriate module_{get,put}() calls), but that is left for
potential future patches.

Reported-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/4eb2e1971326651a3b@agluck-desktop.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-08 16:17:11 +01:00
Linus Torvalds 403299a851 Merge branch 'upstream/xen-settime' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'upstream/xen-settime' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xen/dom0: set wallclock time in Xen
  xen: add dom0_op hypercall
  xen/acpi: Domain0 acpi parser related platform hypercall
2011-11-06 20:15:05 -08:00
Linus Torvalds 06d381484f Merge branch 'stable/vmalloc-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/vmalloc-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  net: xen-netback: use API provided by xenbus module to map rings
  block: xen-blkback: use API provided by xenbus module to map rings
  xen: use generic functions instead of xen_{alloc, free}_vm_area()
2011-11-06 18:31:36 -08:00
Linus Torvalds a0a4194c94 Merge branch 'for-next' of git://git.infradead.org/users/sameo/mfd-2.6
* 'for-next' of git://git.infradead.org/users/sameo/mfd-2.6: (80 commits)
  mfd: Fix missing abx500 header file updates
  mfd: Add missing <linux/io.h> include to intel_msic
  x86, mrst: add platform support for MSIC MFD driver
  mfd: Expose TurnOnStatus in ab8500 sysfs
  mfd: Remove support for early drop ab8500 chip
  mfd: Add support for ab8500 v3.3
  mfd: Add ab8500 interrupt disable hook
  mfd: Convert db8500-prcmu panic() into pr_crit()
  mfd: Refactor db8500-prcmu request_clock() function
  mfd: Rename db8500-prcmu init function
  mfd: Fix db5500-prcmu defines
  mfd: db8500-prcmu voltage domain consumers additions
  mfd: db8500-prcmu reset code retrieval
  mfd: db8500-prcmu tweak for modem wakeup
  mfd: Add db8500-pcmu watchdog accessor functions for watchdog
  mfd: hwacc power state db8500-prcmu accessor
  mfd: Add db8500-prcmu accessors for PLL and SGA clock
  mfd: Move to the new db500 PRCMU API
  mfd: Create a common interface for dbx500 PRCMU drivers
  mfd: Initialize DB8500 PRCMU regs
  ...

Fix up trivial conflicts in
	arch/arm/mach-imx/mach-mx31moboard.c
	arch/arm/mach-omap2/board-omap3beagle.c
	arch/arm/mach-u300/include/mach/irqs.h
	drivers/mfd/wm831x-spi.c
2011-11-03 09:40:51 -07:00
Linus Torvalds dc47d3810c Merge git://github.com/herbertx/crypto
* git://github.com/herbertx/crypto: (48 commits)
  crypto: user - Depend on NET instead of selecting it
  crypto: user - Add dependency on NET
  crypto: talitos - handle descriptor not found in error path
  crypto: user - Initialise match in crypto_alg_match
  crypto: testmgr - add twofish tests
  crypto: testmgr - add blowfish test-vectors
  crypto: Make hifn_795x build depend on !ARCH_DMA_ADDR_T_64BIT
  crypto: twofish-x86_64-3way - fix ctr blocksize to 1
  crypto: blowfish-x86_64 - fix ctr blocksize to 1
  crypto: whirlpool - count rounds from 0
  crypto: Add userspace report for compress type algorithms
  crypto: Add userspace report for cipher type algorithms
  crypto: Add userspace report for rng type algorithms
  crypto: Add userspace report for pcompress type algorithms
  crypto: Add userspace report for nivaead type algorithms
  crypto: Add userspace report for aead type algorithms
  crypto: Add userspace report for givcipher type algorithms
  crypto: Add userspace report for ablkcipher type algorithms
  crypto: Add userspace report for blkcipher type algorithms
  crypto: Add userspace report for ahash type algorithms
  ...
2011-11-01 09:24:41 -07:00
Christopher Yeoh fcf634098c Cross Memory Attach
The basic idea behind cross memory attach is to allow MPI programs doing
intra-node communication to do a single copy of the message rather than a
double copy of the message via shared memory.

The following patch attempts to achieve this by allowing a destination
process, given an address and size from a source process, to copy memory
directly from the source process into its own address space via a system
call.  There is also a symmetrical ability to copy from the current
process's address space into a destination process's address space.

- Use of /proc/pid/mem has been considered, but there are issues with
  using it:
  - Does not allow for specifying iovecs for both src and dest, assuming
    preadv or pwritev was implemented either the area read from or
  written to would need to be contiguous.
  - Currently mem_read allows only processes who are currently
  ptrace'ing the target and are still able to ptrace the target to read
  from the target. This check could possibly be moved to the open call,
  but its not clear exactly what race this restriction is stopping
  (reason  appears to have been lost)
  - Having to send the fd of /proc/self/mem via SCM_RIGHTS on unix
  domain socket is a bit ugly from a userspace point of view,
  especially when you may have hundreds if not (eventually) thousands
  of processes  that all need to do this with each other
  - Doesn't allow for some future use of the interface we would like to
  consider adding in the future (see below)
  - Interestingly reading from /proc/pid/mem currently actually
  involves two copies! (But this could be fixed pretty easily)

As mentioned previously use of vmsplice instead was considered, but has
problems.  Since you need the reader and writer working co-operatively if
the pipe is not drained then you block.  Which requires some wrapping to
do non blocking on the send side or polling on the receive.  In all to all
communication it requires ordering otherwise you can deadlock.  And in the
example of many MPI tasks writing to one MPI task vmsplice serialises the
copying.

There are some cases of MPI collectives where even a single copy interface
does not get us the performance gain we could.  For example in an
MPI_Reduce rather than copy the data from the source we would like to
instead use it directly in a mathops (say the reduce is doing a sum) as
this would save us doing a copy.  We don't need to keep a copy of the data
from the source.  I haven't implemented this, but I think this interface
could in the future do all this through the use of the flags - eg could
specify the math operation and type and the kernel rather than just
copying the data would apply the specified operation between the source
and destination and store it in the destination.

Although we don't have a "second user" of the interface (though I've had
some nibbles from people who may be interested in using it for intra
process messaging which is not MPI).  This interface is something which
hardware vendors are already doing for their custom drivers to implement
fast local communication.  And so in addition to this being useful for
OpenMPI it would mean the driver maintainers don't have to fix things up
when the mm changes.

There was some discussion about how much faster a true zero copy would
go. Here's a link back to the email with some testing I did on that:

http://marc.info/?l=linux-mm&m=130105930902915&w=2

There is a basic man page for the proposed interface here:

http://ozlabs.org/~cyeoh/cma/process_vm_readv.txt

This has been implemented for x86 and powerpc, other architecture should
mainly (I think) just need to add syscall numbers for the process_vm_readv
and process_vm_writev. There are 32 bit compatibility versions for
64-bit kernels.

For arch maintainers there are some simple tests to be able to quickly
verify that the syscalls are working correctly here:

http://ozlabs.org/~cyeoh/cma/cma-test-20110718.tgz

Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: <linux-man@vger.kernel.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:44 -07:00
Linus Torvalds 1bc87b0055 Merge branch 'kvm-updates/3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm
* 'kvm-updates/3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm: (75 commits)
  KVM: SVM: Keep intercepting task switching with NPT enabled
  KVM: s390: implement sigp external call
  KVM: s390: fix register setting
  KVM: s390: fix return value of kvm_arch_init_vm
  KVM: s390: check cpu_id prior to using it
  KVM: emulate lapic tsc deadline timer for guest
  x86: TSC deadline definitions
  KVM: Fix simultaneous NMIs
  KVM: x86 emulator: convert push %sreg/pop %sreg to direct decode
  KVM: x86 emulator: switch lds/les/lss/lfs/lgs to direct decode
  KVM: x86 emulator: streamline decode of segment registers
  KVM: x86 emulator: simplify OpMem64 decode
  KVM: x86 emulator: switch src decode to decode_operand()
  KVM: x86 emulator: qualify OpReg inhibit_byte_regs hack
  KVM: x86 emulator: switch OpImmUByte decode to decode_imm()
  KVM: x86 emulator: free up some flag bits near src, dst
  KVM: x86 emulator: switch src2 to generic decode_operand()
  KVM: x86 emulator: expand decode flags to 64 bits
  KVM: x86 emulator: split dst decode to a generic decode_operand()
  KVM: x86 emulator: move memop, memopp into emulation context
  ...
2011-10-30 15:36:45 -07:00
Linus Torvalds 0e59e7e7fe Merge branch 'next-rebase' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci
* 'next-rebase' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci:
  PCI: Clean-up MPS debug output
  pci: Clamp pcie_set_readrq() when using "performance" settings
  PCI: enable MPS "performance" setting to properly handle bridge MPS
  PCI: Workaround for Intel MPS errata
  PCI: Add support for PASID capability
  PCI: Add implementation for PRI capability
  PCI: Export ATS functions to modules
  PCI: Move ATS implementation into own file
  PCI / PM: Remove unnecessary error variable from acpi_dev_run_wake()
  PCI hotplug: acpiphp: Prevent deadlock on PCI-to-PCI bridge remove
  PCI / PM: Extend PME polling to all PCI devices
  PCI quirk: mmc: Always check for lower base frequency quirk for Ricoh 1180:e823
  PCI: Make pci_setup_bridge() non-static for use by arch code
  x86: constify PCI raw ops structures
  PCI: Add quirk for known incorrect MPSS
  PCI: Add Solarflare vendor ID and SFC4000 device IDs
2011-10-28 14:20:44 -07:00
Linus Torvalds f362f98e7c Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/vfs-queue
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/vfs-queue: (21 commits)
  leases: fix write-open/read-lease race
  nfs: drop unnecessary locking in llseek
  ext4: replace cut'n'pasted llseek code with generic_file_llseek_size
  vfs: add generic_file_llseek_size
  vfs: do (nearly) lockless generic_file_llseek
  direct-io: merge direct_io_walker into __blockdev_direct_IO
  direct-io: inline the complete submission path
  direct-io: separate map_bh from dio
  direct-io: use a slab cache for struct dio
  direct-io: rearrange fields in dio/dio_submit to avoid holes
  direct-io: fix a wrong comment
  direct-io: separate fields only used in the submission path from struct dio
  vfs: fix spinning prevention in prune_icache_sb
  vfs: add a comment to inode_permission()
  vfs: pass all mask flags check_acl and posix_acl_permission
  vfs: add hex format for MAY_* flag values
  vfs: indicate that the permission functions take all the MAY_* flags
  compat: sync compat_stats with statfs.
  vfs: add "device" tag to /proc/self/mountstats
  cleanup: vfs: small comment fix for block_invalidatepage
  ...

Fix up trivial conflict in fs/gfs2/file.c (llseek changes)
2011-10-28 10:49:34 -07:00
Eric W. Biederman 1448c721e4 compat: sync compat_stats with statfs.
This was found by inspection while tracking a similar
bug in compat_statfs64, that has been fixed in mainline
since decemeber.

- This fixes a bug where not all of the f_spare fields
  were cleared on mips and s390.
- Add the f_flags field to struct compat_statfs
- Copy f_flags to userspace in case someone cares.
- Use __clear_user to copy the f_spare field to userspace
  to ensure that all of the elements of f_spare are cleared.
  On some architectures f_spare is has 5 ints and on some
  architectures f_spare only has 4 ints.  Which makes
  the previous technique of clearing each int individually
  broken.

I don't expect anyone actually uses the old statfs system
call anymore but if they do let them benefit from having
the compat and the native version working the same.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2011-10-28 14:58:53 +02:00
Linus Torvalds d630ba565f Merge branch 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: uv2: Workaround for UV2 Hub bug (system global address format)
2011-10-28 05:43:56 -07:00
Linus Torvalds 5fd862f1db Merge branch 'x86-spinlocks-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-spinlocks-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, ticketlock: remove obsolete comment
  x86, cmpxchg: Use __compiletime_error() to make usage messages a bit nicer
  x86, ticketlock: Make __ticket_spin_trylock common
  x86, ticketlock: Convert __ticket_spin_lock to use xadd()
  x86, ticketlock: Convert spin loop to C
  x86, ticketlock: Clean up types and accessors
  x86: Use xadd helper more widely
  x86: Add xadd helper macro
  x86, cmpxchg: Unify cmpxchg into cmpxchg.h
  x86, cmpxchg: Move 64-bit set64_bit() to match 32-bit
  x86, cmpxchg: Move 32-bit __cmpxchg_wrong_size to match 64 bit.
  x86, cmpxchg: <linux/alternative.h> has LOCK_PREFIX
2011-10-28 05:43:29 -07:00
Linus Torvalds 8e6d539e0f Merge branch 'x86-rdrand-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-rdrand-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, random: Verify RDRAND functionality and allow it to be disabled
  x86, random: Architectural inlines to get random integers with RDRAND
  random: Add support for architectural random hooks

Fix up trivial conflicts in drivers/char/random.c: the architectural
random hooks touched "get_random_int()" that was simplified to use MD5
and not do the keyptr thing any more (see commit 6e5714eaf77d: "net:
Compute protocol sequence numbers and fragment IDs using MD5").
2011-10-28 05:29:07 -07:00
Linus Torvalds 8237eb946a Merge branch 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, microcode, AMD: Add microcode revision to /proc/cpuinfo
  x86, microcode: Correct microcode revision format
  coretemp: Get microcode revision from cpu_data
  x86, intel: Use c->microcode for Atom errata check
  x86, intel: Output microcode revision in /proc/cpuinfo
  x86, microcode: Don't request microcode from userspace unnecessarily

Fix up trivial conflicts in arch/x86/kernel/cpu/amd.c (conflict between
moving AMD BSP code to cpu_dev helper function and adding AMD microcode
revision to /proc/cpuinfo code)
2011-10-28 05:14:48 -07:00
Linus Torvalds 107095a946 Merge branch 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, cpu: Add cpufeature flag for PCIDs
2011-10-28 05:04:04 -07:00
Linus Torvalds e34eb39c1c Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, amd: Include linux/elf.h since we use stuff from asm/elf.h
  x86: cache_info: Update calculation of AMD L3 cache indices
  x86: cache_info: Kill the atomic allocation in amd_init_l3_cache()
  x86: cache_info: Kill the moronic shadow struct
  x86: cache_info: Remove bogus free of amd_l3_cache data
  x86, amd: Include elf.h explicitly, prepare the code for the module.h split
  x86-32, amd: Move va_align definition to unbreak 32-bit build
  x86, amd: Move BSP code to cpu_dev helper
  x86: Add a BSP cpu_dev helper
  x86, amd: Avoid cache aliasing penalties on AMD family 15h
2011-10-28 05:03:12 -07:00
Linus Torvalds dfa4a423cf Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86-64, unistd: Remove bogus __IGNORE_getcpu
  x86, mm, trivial: Remove unnecessary get_order() in free_thread_info()
  x86, cleanup: Remove unneeded version.h include from arch/x86/
2011-10-26 17:43:08 +02:00
Linus Torvalds 7b86572a7a Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86-64: Fix CFI data for interrupt frames
  x86-64: Don't apply destructive erratum workaround on unaffected CPUs
2011-10-26 17:42:03 +02:00
Linus Torvalds 0791e98dd1 Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/irq: Standardize on CONFIG_SPARSE_IRQ=y
  x86, ioapic: Clean up ioapic/apic_id usage
  x86, ioapic: Factor out print_IO_APIC() to only print one io apic
  x86, ioapic: Print out irte with right ioapic index
  x86, ioapic: Split up setup_ioapic_entry()
  x86, ioapic: Pass struct irq_attr * to setup_ioapic_irq()
  apic, i386/bigsmp: Fix false warnings regarding logical APIC ID mismatches
2011-10-26 17:30:33 +02:00
Linus Torvalds 7115e3fcf4 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (121 commits)
  perf symbols: Increase symbol KSYM_NAME_LEN size
  perf hists browser: Refuse 'a' hotkey on non symbolic views
  perf ui browser: Use libslang to read keys
  perf tools: Fix tracing info recording
  perf hists browser: Elide DSO column when it is set to just one DSO, ditto for threads
  perf hists: Don't consider filtered entries when calculating column widths
  perf hists: Don't decay total_period for filtered entries
  perf hists browser: Honour symbol_conf.show_{nr_samples,total_period}
  perf hists browser: Do not exit on tab key with single event
  perf annotate browser: Don't change selection line when returning from callq
  perf tools: handle endianness of feature bitmap
  perf tools: Add prelink suggestion to dso update message
  perf script: Fix unknown feature comment
  perf hists browser: Apply the dso and thread filters when merging new batches
  perf hists: Move the dso and thread filters from hist_browser
  perf ui browser: Honour the xterm colors
  perf top tui: Give color hints just on the percentage, like on --stdio
  perf ui browser: Make the colors configurable and change the defaults
  perf tui: Remove unneeded call to newtCls on startup
  perf hists: Don't format the percentage on hist_entry__snprintf
  ...

Fix up conflicts in arch/x86/kernel/kprobes.c manually.

Ingo's tree did the insane "add volatile to const array", which just
doesn't make sense ("volatile const"?).  But we could remove the const
*and* make the array volatile to make doubly sure that gcc doesn't
optimize it away..

Also fix up kernel/trace/ring_buffer.c non-data-conflicts manually: the
reader_lock has been turned into a raw lock by the core locking merge,
and there was a new user of it introduced in this perf core merge.  Make
sure that new use also uses the raw accessor functions.
2011-10-26 17:03:38 +02:00
Linus Torvalds 982653009b Merge branch 'core-iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, ioapic: Consolidate the explicit EOI code
  x86, ioapic: Restore the mask bit correctly in eoi_ioapic_irq()
  x86, kdump, ioapic: Reset remote-IRR in clear_IO_APIC
  iommu: Rename the DMAR and INTR_REMAP config options
  x86, ioapic: Define irq_remap_modify_chip_defaults()
  x86, msi, intr-remap: Use the ioapic set affinity routine
  iommu: Cleanup ifdefs in detect_intel_iommu()
  iommu: No need to set dmar_disabled in check_zero_address()
  iommu: Move IOMMU specific code to intel-iommu.c
  intr_remap: Call dmar_dev_scope_init() explicitly
  x86, x2apic: Enable the bios request for x2apic optout
2011-10-26 16:11:53 +02:00
Linus Torvalds aa77677e0a Merge branch 'staging-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
* 'staging-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1519 commits)
  staging: et131x: Remove redundant check and return statement
  staging: et131x: Mainly whitespace changes to appease checkpatch
  staging: et131x: Remove last of the forward declarations
  staging: et131x: Remove even more forward declarations
  staging: et131x: Remove yet more forward declarations
  staging: et131x: Remove more forward declarations
  staging: et131x: Remove forward declaration of et131x_adapter_setup
  staging: et131x: Remove some forward declarations
  staging: et131x: Remove unused rx_ring.recv_packet_pool
  staging: et131x: Remove call to find pci pm capability
  staging: et131x: Remove redundant et131x_reset_recv() call
  staging: et131x: Remove unused rx_ring.recv_buffer_pool
  Staging: bcm: Fix three initialization errors in InterfaceDld.c
  Staging: bcm: Fix coding style issues in InterfaceDld.c
  staging:iio:dac: Add AD5360 driver
  staging:iio:trigger:bfin-timer: Fix compile error
  Staging: vt6655: add some range checks before memcpy()
  Staging: vt6655: whitespace fixes to iotcl.c
  Staging: vt6656: add some range checks before memcpy()
  Staging: vt6656: whitespace cleanups in ioctl.c
  ...

Fix up conflicts in:
 - drivers/{Kconfig,Makefile}, drivers/staging/{Kconfig,Makefile}:
	vg driver movement
 - drivers/staging/brcm80211/brcmfmac/{dhd_linux.c,mac80211_if.c}:
	driver removal vs now stale changes
 - drivers/staging/rtl8192e/r8192E_core.c:
	driver removal vs now stale changes
 - drivers/staging/et131x/et131*:
	driver consolidation into one file, tried to do fixups
2011-10-26 15:39:02 +02:00
Linus Torvalds 59e5253417 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (59 commits)
  MAINTAINERS: linux-m32r is moderated for non-subscribers
  linux@lists.openrisc.net is moderated for non-subscribers
  Drop default from "DM365 codec select" choice
  parisc: Kconfig: cleanup Kernel page size default
  Kconfig: remove redundant CONFIG_ prefix on two symbols
  cris: remove arch/cris/arch-v32/lib/nand_init.S
  microblaze: add missing CONFIG_ prefixes
  h8300: drop puzzling Kconfig dependencies
  MAINTAINERS: microblaze-uclinux@itee.uq.edu.au is moderated for non-subscribers
  tty: drop superfluous dependency in Kconfig
  ARM: mxc: fix Kconfig typo 'i.MX51'
  Fix file references in Kconfig files
  aic7xxx: fix Kconfig references to READMEs
  Fix file references in drivers/ide/
  thinkpad_acpi: Fix printk typo 'bluestooth'
  bcmring: drop commented out line in Kconfig
  btmrvl_sdio: fix typo 'btmrvl_sdio_sd6888'
  doc: raw1394: Trivial typo fix
  CIFS: Don't free volume_info->UNC until we are entirely done with it.
  treewide: Correct spelling of successfully in comments
  ...
2011-10-25 12:11:02 +02:00
Greg Kroah-Hartman 43a3beb6da Merge branch 'staging-next' into Linux 3.1
This was done to resolve a conflict in the
drivers/staging/comedi/drivers/ni_labpc.c file that resolved a build
bugfix in Linus's tree with a "better" bugfix that was in the
staging-next tree that resolved the issue in a more complete manner.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-25 09:18:11 +02:00
Linus Torvalds 31018acd4c Merge branches 'stable/bug.fixes-3.2' and 'stable/mmu.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/bug.fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/p2m/debugfs: Make type_name more obvious.
  xen/p2m/debugfs: Fix potential pointer exception.
  xen/enlighten: Fix compile warnings and set cx to known value.
  xen/xenbus: Remove the unnecessary check.
  xen/irq: If we fail during msi_capability_init return proper error code.
  xen/events: Don't check the info for NULL as it is already done.
  xen/events: BUG() when we can't allocate our event->irq array.

* 'stable/mmu.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: Fix selfballooning and ensure it doesn't go too far
  xen/gntdev: Fix sleep-inside-spinlock
  xen: modify kernel mappings corresponding to granted pages
  xen: add an "highmem" parameter to alloc_xenballooned_pages
  xen/p2m: Use SetPagePrivate and its friends for M2P overrides.
  xen/p2m: Make debug/xen/mmu/p2m visible again.
  Revert "xen/debug: WARN_ON when identity PFN has no _PAGE_IOMAP flag set."
2011-10-25 09:17:47 +02:00
Alan Cox 42c2544b2d x86, mrst: Some drivers need to known when an SCU is available
Add a notifier so that drivers can hook into SCU availability in order to
take actions post initialisation when/if the SCU becomes available.

In the ideal world we wouldn't need this and we could avoid any init
dependancies of this form, but in practice we can't do it for some cases.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2011-10-24 14:09:15 +02:00
Jan Beulich 72da0b07b1 x86: constify PCI raw ops structures
As with any other such change, the goal is to prevent inadvertent
writes to these structures (assuming DEBUG_RODATA is enabled), and to
separate data (possibly frequently) written to from such never getting
modified.

Reviewed-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-10-14 09:05:28 -07:00
Andi Kleen 506ed6b53e x86, intel: Output microcode revision in /proc/cpuinfo
I got a request to make it easier to determine the microcode
update level on Intel CPUs. This patch adds a new "microcode"
field to /proc/cpuinfo.

The microcode level is also outputed on fatal machine checks
together with the other CPUID model information.

I removed the respective code from the microcode update driver,
it just reads the field from cpu_data. Also when the microcode
is updated it fills in the new values too.

I had to add a memory barrier to native_cpuid to prevent it
being optimized away when the result is not used.

This turns out to clean up further code which already got this
information manually. This is done in followon patches.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1318466795-7393-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-14 13:16:35 +02:00
Yinghai Lu 141d55e6cc x86/irq: Standardize on CONFIG_SPARSE_IRQ=y
Sparseirq got introduced in v2.6.28 and Thomas did a huge cleanup
around v2.6.38 that eliminated basically all disadvantages
of it.

So we can remove non-sparseirq support now and simplify
our IRQ degrees of freedom a bit.

Suggested-and-acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/4E95E21D.6090200@oracle.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-13 12:12:12 +02:00
Robert Richter b716916679 perf, x86: Implement IBS initialization
This patch implements IBS feature detection and initialzation. The
code is shared between perf and oprofile. If IBS is available on the
system for perf, a pmu is setup.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1316597423-25723-3-git-send-email-robert.richter@amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-10 06:57:16 +02:00
Robert Richter ee5789dbcc perf, x86: Share IBS macros between perf and oprofile
Moving IBS macros from oprofile to <asm/perf_event.h> to make it
available to perf. No additional changes.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1316597423-25723-2-git-send-email-robert.richter@amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-10 06:57:11 +02:00
Don Zickus b227e23399 x86, nmi: Add in logic to handle multiple events and unknown NMIs
Previous patches allow the NMI subsystem to process multipe NMI events
in one NMI.  As previously discussed this can cause issues when an event
triggered another NMI but is processed in the current NMI.  This causes the
next NMI to go unprocessed and become an 'unknown' NMI.

To handle this, we first have to flag whether or not the NMI handler handled
more than one event or not.  If it did, then there exists a chance that
the next NMI might be already processed.  Once the NMI is flagged as a
candidate to be swallowed, we next look for a back-to-back NMI condition.

This is determined by looking at the %rip from pt_regs.  If it is the same
as the previous NMI, it is assumed the cpu did not have a chance to jump
back into a non-NMI context and execute code and instead handled another NMI.

If both of those conditions are true then we will swallow any unknown NMI.

There still exists a chance that we accidentally swallow a real unknown NMI,
but for now things seem better.

An optimization has also been added to the nmi notifier rountine.  Because x86
can latch up to one NMI while currently processing an NMI, we don't have to
worry about executing _all_ the handlers in a standalone NMI.  The idea is
if multiple NMIs come in, the second NMI will represent them.  For those
back-to-back NMI cases, we have the potentail to drop NMIs.  Therefore only
execute all the handlers in the second half of a detected back-to-back NMI.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1317409584-23662-5-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-10 06:57:01 +02:00
Don Zickus 9c48f1c629 x86, nmi: Wire up NMI handlers to new routines
Just convert all the files that have an nmi handler to the new routines.
Most of it is straight forward conversion.  A couple of places needed some
tweaking like kgdb which separates the debug notifier from the nmi handler
and mce removes a call to notify_die.

[Thanks to Ying for finding out the history behind that mce call

https://lkml.org/lkml/2010/5/27/114

And Boris responding that he would like to remove that call because of it

https://lkml.org/lkml/2011/9/21/163]

The things that get converted are the registeration/unregistration routines
and the nmi handler itself has its args changed along with code removal
to check which list it is on (most are on one NMI list except for kgdb
which has both an NMI routine and an NMI Unknown routine).

Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Corey Minyard <minyard@acm.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Corey Minyard <minyard@acm.org>
Cc: Jack Steiner <steiner@sgi.com>
Link: http://lkml.kernel.org/r/1317409584-23662-4-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-10 06:56:57 +02:00
Don Zickus c9126b2ee8 x86, nmi: Create new NMI handler routines
The NMI handlers used to rely on the notifier infrastructure.  This worked
great until we wanted to support handling multiple events better.

One of the key ideas to the nmi handling is to process _all_ the handlers for
each NMI.  The reason behind this switch is because NMIs are edge triggered.
If enough NMIs are triggered, then they could be lost because the cpu can
only latch at most one NMI (besides the one currently being processed).

In order to deal with this we have decided to process all the NMI handlers
for each NMI.  This allows the handlers to determine if they recieved an
event or not (the ones that can not determine this will be left to fend
for themselves on the unknown NMI list).

As a result of this change it is now possible to have an extra NMI that
was destined to be received for an already processed event.  Because the
event was processed in the previous NMI, this NMI gets dropped and becomes
an 'unknown' NMI.  This of course will cause printks that scare people.

However, we prefer to have extra NMIs as opposed to losing NMIs and as such
are have developed a basic mechanism to catch most of them.  That will be
a later patch.

To accomplish this idea, I unhooked the nmi handlers from the notifier
routines and created a new mechanism loosely based on doIRQ.  The reason
for this is the notifier routines have a couple of shortcomings.  One we
could't guarantee all future NMI handlers used NOTIFY_OK instead of
NOTIFY_STOP.  Second, we couldn't keep track of the number of events being
handled in each routine (most only handle one, perf can handle more than one).
Third, I wanted to eventually display which nmi handlers are registered in
the system in /proc/interrupts to help see who is generating NMIs.

The patch below just implements the new infrastructure but doesn't wire it up
yet (that is the next patch).  Its design is based on doIRQ structs and the
atomic notifier routines.  So the rcu stuff in the patch isn't entirely untested
(as the notifier routines have soaked it) but it should be double checked in
case I copied the code wrong.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1317409584-23662-3-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-10 06:56:52 +02:00
Gleb Natapov 144d31e6f1 perf, intel: Use GO/HO bits in perf-ctr
Intel does not have guest/host-only bit in perf counters like AMD
does.  To support GO/HO bits KVM needs to switch EVENTSELn values
(or PERF_GLOBAL_CTRL if available) at a guest entry. If a counter is
configured to count only in a guest mode it stays disabled in a host,
but VMX is configured to switch it to enabled value during guest entry.

This patch adds GO/HO tracking to Intel perf code and provides interface
for KVM to get a list of MSRs that need to be switched on a guest entry.

Only cpus with architectural PMU (v1 or later) are supported with this
patch.  To my knowledge there is not p6 models with VMX but without
architectural PMU and p4 with VMX are rare and the interface is general
enough to support them if need arise.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1317816084-18026-7-git-send-email-gleb@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-10 06:56:42 +02:00