Commit Graph

32 Commits

Author SHA1 Message Date
Juergen Gross 71c208dd54 x86/xen: Zero MSR_IA32_SPEC_CTRL before suspend
Older Xen versions (4.5 and before) might have problems migrating pv
guests with MSR_IA32_SPEC_CTRL having a non-zero value. So before
suspending zero that MSR and restore it after being resumed.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Cc: stable@vger.kernel.org
Cc: xen-devel@lists.xenproject.org
Cc: boris.ostrovsky@oracle.com
Link: https://lkml.kernel.org/r/20180226140818.4849-1-jgross@suse.com
2018-02-28 16:03:19 +01:00
Linus Torvalds 051089a2ee xen: features and fixes for v4.15-rc1
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Merge tag 'for-linus-4.15-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:
 "Xen features and fixes for v4.15-rc1

  Apart from several small fixes it contains the following features:

   - a series by Joao Martins to add vdso support of the pv clock
     interface

   - a series by Juergen Gross to add support for Xen pv guests to be
     able to run on 5 level paging hosts

   - a series by Stefano Stabellini adding the Xen pvcalls frontend
     driver using a paravirtualized socket interface"

* tag 'for-linus-4.15-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (34 commits)
  xen/pvcalls: fix potential endless loop in pvcalls-front.c
  xen/pvcalls: Add MODULE_LICENSE()
  MAINTAINERS: xen, kvm: track pvclock-abi.h changes
  x86/xen/time: setup vcpu 0 time info page
  x86/xen/time: set pvclock flags on xen_time_init()
  x86/pvclock: add setter for pvclock_pvti_cpu0_va
  ptp_kvm: probe for kvm guest availability
  xen/privcmd: remove unused variable pageidx
  xen: select grant interface version
  xen: update arch/x86/include/asm/xen/cpuid.h
  xen: add grant interface version dependent constants to gnttab_ops
  xen: limit grant v2 interface to the v1 functionality
  xen: re-introduce support for grant v2 interface
  xen: support priv-mapping in an HVM tools domain
  xen/pvcalls: remove redundant check for irq >= 0
  xen/pvcalls: fix unsigned less than zero error check
  xen/time: Return -ENODEV from xen_get_wallclock()
  xen/pvcalls-front: mark expected switch fall-through
  xen: xenbus_probe_frontend: mark expected switch fall-throughs
  xen/time: do not decrease steal time after live migration on xen
  ...
2017-11-16 13:06:27 -08:00
Joao Martins 2229f70b5b x86/xen/time: setup vcpu 0 time info page
In order to support pvclock vdso on xen we need to setup the time
info page for vcpu 0 and register the page with Xen using the
VCPUOP_register_vcpu_time_memory_area hypercall. This hypercall
will also forcefully update the pvti which will set some of the
necessary flags for vdso. Afterwards we check if it supports the
PVCLOCK_TSC_STABLE_BIT flag which is mandatory for having
vdso/vsyscall support. And if so, it will set the cpu 0 pvti that
will be later on used when mapping the vdso image.

The xen headers are also updated to include the new hypercall for
registering the secondary vcpu_time_info struct.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2017-11-08 16:33:14 -05:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Vitaly Kuznetsov 9963236d7c x86/xen: split suspend.c for PV and PVHVM guests
Slit the code in suspend.c into suspend_pv.c and suspend_hvm.c.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2017-05-02 11:09:17 +02:00
Linus Torvalds c9bed1cf51 xen: features and fixes for 4.5-rc0
- Stolen ticks and PV wallclock support for arm/arm64.
 - Add grant copy ioctl to gntdev device.
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Merge tag 'for-linus-4.5-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from David Vrabel:
 "Xen features and fixes for 4.5-rc0:

   - Stolen ticks and PV wallclock support for arm/arm64

   - Add grant copy ioctl to gntdev device"

* tag 'for-linus-4.5-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/gntdev: add ioctl for grant copy
  x86/xen: don't reset vcpu_info on a cancelled suspend
  xen/gntdev: constify mmu_notifier_ops structures
  xen/grant-table: constify gnttab_ops structure
  xen/time: use READ_ONCE
  xen/x86: convert remaining timespec to timespec64 in xen_pvclock_gtod_notify
  xen/x86: support XENPF_settime64
  xen/arm: set the system time in Xen via the XENPF_settime64 hypercall
  xen/arm: introduce xen_read_wallclock
  arm: extend pvclock_wall_clock with sec_hi
  xen: introduce XENPF_settime64
  xen/arm: introduce HYPERVISOR_platform_op on arm and arm64
  xen: rename dom0_op to platform_op
  xen/arm: account for stolen ticks
  arm64: introduce CONFIG_PARAVIRT, PARAVIRT_TIME_ACCOUNTING and pv_time_ops
  arm: introduce CONFIG_PARAVIRT, PARAVIRT_TIME_ACCOUNTING and pv_time_ops
  missing include asm/paravirt.h in cputime.c
  xen: move xen_setup_runstate_info and get_runstate_snapshot to drivers/xen/time.c
2016-01-12 13:05:36 -08:00
Ouyang Zhaowei (Charles) 6a1f513776 x86/xen: don't reset vcpu_info on a cancelled suspend
On a cancelled suspend the vcpu_info location does not change (it's
still in the per-cpu area registered by xen_vcpu_setup()).  So do not
call xen_hvm_init_shared_info() which would make the kernel think its
back in the shared info.  With the wrong vcpu_info, events cannot be
received and the domain will hang after a cancelled suspend.

Signed-off-by: Charles Ouyang <ouyangzhaowei@huawei.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-01-04 11:49:25 +00:00
Andrew Morton facca61683 arch/x86/xen/suspend.c: include xen/xen.h
Fix the build warning:

  arch/x86/xen/suspend.c: In function 'xen_arch_pre_suspend':
  arch/x86/xen/suspend.c:70:9: error: implicit declaration of function 'xen_pv_domain' [-Werror=implicit-function-declaration]
          if (xen_pv_domain())
              ^

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-12-29 17:45:49 -08:00
Boris Ostrovsky de0afc9bde xen: Resume PMU from non-atomic context
Resuming PMU currently triggers a warning from ___might_sleep() (assuming
CONFIG_DEBUG_ATOMIC_SLEEP is set) when xen_pmu_init() allocates GFP_KERNEL
page because we are in state resembling atomic context.

Move resuming PMU to xen_arch_resume() which is called in regular context.
For symmetry move suspending PMU to xen_arch_suspend() as well.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: <stable@vger.kernel.org> # 4.3
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-12-02 17:17:17 +00:00
Boris Ostrovsky 65d0cf0be7 xen/PMU: Initialization code for Xen PMU
Map shared data structure that will hold CPU registers, VPMU context,
V/PCPU IDs of the CPU interrupted by PMU interrupt. Hypervisor fills
this information in its handler and passes it to the guest for further
processing.

Set up PMU VIRQ.

Now that perf infrastructure will assume that PMU is available on a PV
guest we need to be careful and make sure that accesses via RDPMC
instruction don't cause fatal traps by the hypervisor. Provide a nop
RDPMC handler.

For the same reason avoid issuing a warning on a write to APIC's LVTPC.

Both of these will be made functional in later patches.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-08-20 12:25:20 +01:00
Boris Ostrovsky 2b953a5e99 xen: Suspend ticks on all CPUs during suspend
Commit 77e32c89a7 ("clockevents: Manage device's state separately for
the core") decouples clockevent device's modes from states. With this
change when a Xen guest tries to resume, it won't be calling its
set_mode op which needs to be done on each VCPU in order to make the
hypervisor aware that we are in oneshot mode.

This happens because clockevents_tick_resume() (which is an intermediate
step of resuming ticks on a processor) doesn't call clockevents_set_state()
anymore and because during suspend clockevent devices on all VCPUs (except
for the one doing the suspend) are left in ONESHOT state. As result, during
resume the clockevents state machine will assume that device is already
where it should be and doesn't need to be updated.

To avoid this problem we should suspend ticks on all VCPUs during
suspend.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-04-29 17:10:05 +01:00
Thomas Gleixner f46481d0a7 tick/xen: Provide and use tick_suspend_local() and tick_resume_local()
Xen calls on every cpu into tick_resume() which is just wrong.
tick_resume() is for the syscore global suspend/resume
invocation. What XEN really wants is a per cpu local resume
function.

Provide a tick_resume_local() function and use it in XEN.

Also provide a complementary tick_suspend_local() and modify
tick_unfreeze() and tick_freeze(), respectively, to use the
new local tick resume/suspend functions.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[ Combined two patches, rebased, modified subject/changelog. ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1698741.eezk9tnXtG@vostro.rjw.lan
[ Merged to latest timers/core. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-01 14:23:00 +02:00
Thomas Gleixner 4ffee521f3 clockevents: Make suspend/resume calls explicit
clockevents_notify() is a leftover from the early design of the
clockevents facility. It's really not a notification mechanism,
it's a multiplex call.

We are way better off to have explicit calls instead of this
monstrosity. Split out the suspend/resume() calls and invoke
them directly from the call sites.

No locking required at this point because these calls happen
with interrupts disabled and a single cpu online.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[ Rebased on top of 4.0-rc5. ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/713674030.jVm1qaHuPf@vostro.rjw.lan
[ Rebased on top of latest timers/core. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-01 14:22:59 +02:00
David Vrabel aa8532c322 xen: refactor suspend pre/post hooks
New architectures currently have to provide implementations of 5 different
functions: xen_arch_pre_suspend(), xen_arch_post_suspend(),
xen_arch_hvm_post_suspend(), xen_mm_pin_all(), and xen_mm_unpin_all().

Refactor the suspend code to only require xen_arch_pre_suspend() and
xen_arch_post_suspend().

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2014-05-12 17:19:56 +01:00
Konrad Rzeszutek Wilk e9daff24a2 Revert "xen PVonHVM: use E820_Reserved area for shared_info"
This reverts commit 9d02b43dee.

We are doing this b/c on 32-bit PVonHVM with older hypervisors
(Xen 4.1) it ends up bothing up the start_info. This is bad b/c
we use it for the time keeping, and the timekeeping code loops
forever - as the version field never changes. Olaf says to
revert it, so lets do that.

Acked-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-02-14 21:29:31 -05:00
Olaf Hering 9d02b43dee xen PVonHVM: use E820_Reserved area for shared_info
This is a respin of 00e37bdb01
("xen PVonHVM: move shared_info to MMIO before kexec").

Currently kexec in a PVonHVM guest fails with a triple fault because the
new kernel overwrites the shared info page. The exact failure depends on
the size of the kernel image. This patch moves the pfn from RAM into an
E820 reserved memory area.

The pfn containing the shared_info is located somewhere in RAM. This will
cause trouble if the current kernel is doing a kexec boot into a new
kernel. The new kernel (and its startup code) can not know where the pfn
is, so it can not reserve the page. The hypervisor will continue to update
the pfn, and as a result memory corruption occours in the new kernel.

The toolstack marks the memory area FC000000-FFFFFFFF as reserved in the
E820 map. Within that range newer toolstacks (4.3+) will keep 1MB
starting from FE700000 as reserved for guest use. Older Xen4 toolstacks
will usually not allocate areas up to FE700000, so FE700000 is expected
to work also with older toolstacks.

In Xen3 there is no reserved area at a fixed location. If the guest is
started on such old hosts the shared_info page will be placed in RAM. As
a result kexec can not be used.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-02 11:04:01 -04:00
Konrad Rzeszutek Wilk ca08649eb5 Revert "xen PVonHVM: move shared_info to MMIO before kexec"
This reverts commit 00e37bdb01.

During shutdown of PVHVM guests with more than 2VCPUs on certain
machines we can hit the race where the replaced shared_info is not
replaced fast enough and the PV time clock retries reading the same
area over and over without any any success and is stuck in an
infinite loop.

Acked-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-16 13:05:25 -04:00
Olaf Hering 00e37bdb01 xen PVonHVM: move shared_info to MMIO before kexec
Currently kexec in a PVonHVM guest fails with a triple fault because the
new kernel overwrites the shared info page. The exact failure depends on
the size of the kernel image. This patch moves the pfn from RAM into
MMIO space before the kexec boot.

The pfn containing the shared_info is located somewhere in RAM. This
will cause trouble if the current kernel is doing a kexec boot into a
new kernel. The new kernel (and its startup code) can not know where the
pfn is, so it can not reserve the page. The hypervisor will continue to
update the pfn, and as a result memory corruption occours in the new
kernel.

One way to work around this issue is to allocate a page in the
xen-platform pci device's BAR memory range. But pci init is done very
late and the shared_info page is already in use very early to read the
pvclock. So moving the pfn from RAM to MMIO is racy because some code
paths on other vcpus could access the pfn during the small   window when
the old pfn is moved to the new pfn. There is even a  small window were
the old pfn is not backed by a mfn, and during that time all reads
return -1.

Because it is not known upfront where the MMIO region is located it can
not be used right from the start in xen_hvm_init_shared_info.

To minimise trouble the move of the pfn is done shortly before kexec.
This does not eliminate the race because all vcpus are still online when
the syscore_ops will be called. But hopefully there is no work pending
at this point in time. Also the syscore_op is run last which reduces the
risk further.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-19 15:52:05 -04:00
Ian Campbell 03c8142bd2 xen: suspend: add "arch" to pre/post suspend hooks
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>
2011-02-25 16:43:12 +00:00
Stefano Stabellini e057a4b6e0 xen: fix compile issue if XEN is enabled but XEN_PVHVM is disabled
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2011-02-25 16:43:06 +00:00
Stefano Stabellini 512b109ec9 xen: unplug the emulated devices at resume time
Early after being resumed we need to unplug again the emulated devices.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2010-12-02 14:40:53 +00:00
Stefano Stabellini 409771d258 x86: Use xen_vcpuop_clockevent, xen_clocksource and xen wallclock.
Use xen_vcpuop_clockevent instead of hpet and APIC timers as main
clockevent device on all vcpus, use the xen wallclock time as wallclock
instead of rtc and use xen_clocksource as clocksource.
The pv clock algorithm needs to work correctly for the xen_clocksource
and xen wallclock to be usable, only modern Xen versions offer a
reliable pv clock in HVM guests (XENFEAT_hvm_safe_pvclock).

Using the hpet as clocksource means a VMEXIT every time we read/write to
the hpet mmio addresses, pvclock give us a better rating without
VMEXITs. Same goes for the xen wallclock and xen_vcpuop_clockevent

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Don Dutile <ddutile@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-07-26 23:13:25 -07:00
Stefano Stabellini 016b6f5fe8 xen: Add suspend/resume support for PV on HVM guests.
Suspend/resume requires few different things on HVM: the suspend
hypercall is different; we don't need to save/restore memory related
settings; except the shared info page and the callback mechanism.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-07-22 16:46:21 -07:00
Ian Campbell cd52e17ea8 xen: ensure timer tick is resumed even on CPU driving the resume
The core suspend/resume code is run from stop_machine on CPU0 but
parts of the suspend/resume machinery (including xen_arch_resume) are
run on whichever CPU happened to schedule the xenwatch kernel thread.

As part of the non-core resume code xen_arch_resume is called in order
to restart the timer tick on non-boot processors. The boot processor
itself is taken care of by core timekeeping code.

xen_arch_resume uses smp_call_function which does not call the given
function on the current processor. This means that we can end up with
one CPU not receiving timer ticks if the xenwatch thread happened to
be scheduled on CPU > 0.

Use on_each_cpu instead of smp_call_function to ensure the timer tick
is resumed everywhere.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Stable Kernel <stable@kernel.org> # .32.x
2010-06-03 09:34:04 +01:00
Ian Campbell f6eafe3665 xen: call clock resume notifier on all CPUs
tick_resume() is never called on secondary processors. Presumably this
is because they are offlined for suspend on native and so this is
normally taken care of in the CPU onlining path. Under Xen we keep all
CPUs online over a suspend.

This patch papers over the issue for me but I will investigate a more
generic, less hacky, way of doing to the same.

tick_suspend is also only called on the boot CPU which I presume should
be fixed too.

Signed-off-by: Ian Campbell <Ian.Campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2009-12-03 11:14:55 -08:00
Ian Campbell fa24ba62ea xen: correctly restore pfn_to_mfn_list_list after resume
pvops kernels >= 2.6.30 can currently only be saved and restored once. The
second attempt to save results in:

    ERROR Internal error: Frame# in pfn-to-mfn frame list is not in pseudophys
    ERROR Internal error: entry 0: p2m_frame_list[0] is 0xf2c2c2c2, max 0x120000
    ERROR Internal error: Failed to map/save the p2m frame list

I finally narrowed it down to:

    commit cdaead6b4e
        Author: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
        Date:   Fri Feb 27 15:34:59 2009 -0800

            xen: split construction of p2m mfn tables from registration

            Build the p2m_mfn_list_list early with the rest of the p2m table, but
            register it later when the real shared_info structure is in place.

            Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

The unforeseen side-effect of this change was to cause the mfn list list to not
be rebuilt on resume. Prior to this change it would have been rebuilt via
xen_post_suspend() -> xen_setup_shared_info() -> xen_setup_mfn_list_list().

Fix by explicitly calling xen_build_mfn_list_list() from xen_post_suspend().

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-12-03 11:14:51 -08:00
Ingo Molnar 99d0000f71 x86, xen: fix hardirq.h merge fallout
Impact: build fix

This build error:

 arch/x86/xen/suspend.c:22: error: implicit declaration of function 'fix_to_virt'
 arch/x86/xen/suspend.c:22: error: 'FIX_PARAVIRT_BOOTMAP' undeclared (first use in this function)
 arch/x86/xen/suspend.c:22: error: (Each undeclared identifier is reported only once
 arch/x86/xen/suspend.c:22: error: for each function it appears in.)

triggers because the hardirq.h unification removed an implicit fixmap.h
include - on which arch/x86/xen/suspend.c depended. Add the fixmap.h
include explicitly.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-23 11:09:15 +01:00
Mike Travis b78936e14e xen: convert to cpumask_var_t and new cpumask primitives.
Simple change, and eventual space saving when NR_CPUS >> nr_cpu_ids.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
2008-12-16 17:40:57 -08:00
Isaku Yamahata ad55db9fed xen: add xen_arch_resume()/xen_timer_resume hook for ia64 support
add xen_timer_resume() hook.

Timer resume should be done after event channel is resumed.
add xen_arch_resume() hook when ipi becomes usable after resume.
After resume, some cpu specific resource must be reinitialized
on ia64 that can't be set by another cpu.

However available hooks is run once on only one cpu so that ipi has
to be used.

During stop_machine_run() ipi can't be used because interrupt is masked.
So add another hook after stop_machine_run().
Another approach might be use resume hook which is run by
device_resume(). However device_resume() may be executed on
suspend error recovery path.

So it is necessary to determine whether it is executed on real resume path
or error recovery path.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 10:55:50 +02:00
Jeremy Fitzhardinge d07af1f0e3 xen: resume timers on all vcpus
On resume, the vcpu timer modes will not be restored.  The timer
infrastructure doesn't do this for us, since it assumes the cpus
are offline.  We can just poke the other vcpus into the right mode
directly though.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-02 13:25:44 +02:00
Jeremy Fitzhardinge 9c7a794209 xen: restore vcpu_info mapping
If we're using vcpu_info mapping, then make sure its restored on all
processors before relasing them from stop_machine.

The only complication is that if this fails, we can't continue because
we've already made assumptions that the mapping is available (baked in
calls to the _direct versions of the functions, for example).

Fortunately this can only happen with a 32-bit hypervisor, which may
possibly run out of mapping space.  On a 64-bit hypervisor, this is a
non-issue.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-02 13:25:34 +02:00
Jeremy Fitzhardinge 0e91398f2a xen: implement save/restore
This patch implements Xen save/restore and migration.

Saving is triggered via xenbus, which is polled in
drivers/xen/manage.c.  When a suspend request comes in, the kernel
prepares itself for saving by:

1 - Freeze all processes.  This is primarily to prevent any
    partially-completed pagetable updates from confusing the suspend
    process.  If CONFIG_PREEMPT isn't defined, then this isn't necessary.

2 - Suspend xenbus and other devices

3 - Stop_machine, to make sure all the other vcpus are quiescent.  The
    Xen tools require the domain to run its save off vcpu0.

4 - Within the stop_machine state, it pins any unpinned pgds (under
    construction or destruction), performs canonicalizes various other
    pieces of state (mostly converting mfns to pfns), and finally

5 - Suspend the domain

Restore reverses the steps used to save the domain, ending when all
the frozen processes are thawed.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-27 10:11:38 +02:00