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  1. 24 4月, 2015 6 次提交
  3. 12 11月, 2014 1 次提交
  5. 13 12月, 2013 1 次提交
  7. 07 11月, 2013 1 次提交
    • K
      PCI: Add x86_msi.msi_mask_irq() and msix_mask_irq() · 0e4ccb15
      由 Konrad Rzeszutek Wilk 提交于 
      Certain platforms do not allow writes in the MSI-X BARs to setup or tear
down vector values.  To combat against the generic code trying to write to
that and either silently being ignored or crashing due to the pagetables
being marked R/O this patch introduces a platform override.

Note that we keep two separate, non-weak, functions default_mask_msi_irqs()
and default_mask_msix_irqs() for the behavior of the arch_mask_msi_irqs()
and arch_mask_msix_irqs(), as the default behavior is needed by x86 PCI
code.

For Xen, which does not allow the guest to write to MSI-X tables - as the
hypervisor is solely responsible for setting the vector values - we
implement two nops.

This fixes a Xen guest crash when passing a PCI device with MSI-X to the
guest.  See the bugzilla for more details.

[bhelgaas: add bugzilla info]
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=64581Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
CC: Sucheta Chakraborty <sucheta.chakraborty@qlogic.com>
CC: Zhenzhong Duan <zhenzhong.duan@oracle.com>
      0e4ccb15
  9. 29 5月, 2013 1 次提交
    • D
      x86: Increase precision of x86_platform.get/set_wallclock() · 3565184e
      由 David Vrabel 提交于 
      All the virtualized platforms (KVM, lguest and Xen) have persistent
wallclocks that have more than one second of precision.

read_persistent_wallclock() and update_persistent_wallclock() allow
for nanosecond precision but their implementation on x86 with
x86_platform.get/set_wallclock() only allows for one second precision.
This means guests may see a wallclock time that is off by up to 1
second.

Make set_wallclock() and get_wallclock() take a struct timespec
parameter (which allows for nanosecond precision) so KVM and Xen
guests may start with a more accurate wallclock time and a Xen dom0
can maintain a more accurate wallclock for guests.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
      3565184e
  11. 28 1月, 2013 7 次提交
  13. 18 11月, 2012 1 次提交
  15. 12 9月, 2012 4 次提交
  17. 06 6月, 2012 1 次提交
  19. 25 5月, 2012 1 次提交
  21. 02 5月, 2012 1 次提交
  23. 17 4月, 2012 1 次提交
  25. 20 3月, 2012 1 次提交
    • M
      x86: kvmclock: abstract save/restore sched_clock_state · b74f05d6
      由 Marcelo Tosatti 提交于 
      Upon resume from hibernation, CPU 0's hvclock area contains the old
values for system_time and tsc_timestamp. It is necessary for the
hypervisor to update these values with uptodate ones before the CPU uses
them.

Abstract TSC's save/restore sched_clock_state functions and use
restore_state to write to KVM_SYSTEM_TIME MSR, forcing an update.

Also move restore_sched_clock_state before __restore_processor_state,
since the later calls CONFIG_LOCK_STAT's lockstat_clock (also for TSC).
Thanks to Igor Mammedov for tracking it down.

Fixes suspend-to-disk with kvmclock.
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>
      b74f05d6
  27. 05 3月, 2012 1 次提交
    • I
      x86: Introduce x86_cpuinit.early_percpu_clock_init hook · df156f90
      由 Igor Mammedov 提交于 
      When kvm guest uses kvmclock, it may hang on vcpu hot-plug.
This is caused by an overflow in pvclock_get_nsec_offset,

    u64 delta = tsc - shadow->tsc_timestamp;

which in turn is caused by an undefined values from percpu
hv_clock that hasn't been initialized yet.
Uninitialized clock on being booted cpu is accessed from
   start_secondary
    -> smp_callin
      ->  smp_store_cpu_info
        -> identify_secondary_cpu
          -> mtrr_ap_init
            -> mtrr_restore
              -> stop_machine_from_inactive_cpu
                -> queue_stop_cpus_work
                  ...
                    -> sched_clock
                      -> kvm_clock_read
which is well before x86_cpuinit.setup_percpu_clockev call in
start_secondary, where percpu clock is initialized.

This patch introduces a hook that allows to setup/initialize
per_cpu clock early and avoid overflow due to reading
  - undefined values
  - old values if cpu was offlined and then onlined again

Another possible early user of this clock source is ftrace that
accesses it to get timestamps for ring buffer entries. So if
mtrr_ap_init is moved from identify_secondary_cpu to past
x86_cpuinit.setup_percpu_clockev in start_secondary, ftrace
may cause the same overflow/hang on cpu hot-plug anyway.

More complete description of the problem:
  https://lkml.org/lkml/2012/2/2/101

Credits to Marcelo Tosatti <mtosatti@redhat.com> for hook idea.
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>
      df156f90
  29. 07 1月, 2012 1 次提交
  31. 06 12月, 2011 1 次提交
  33. 10 11月, 2011 2 次提交
  35. 13 5月, 2011 1 次提交
    • S
      x86,xen: introduce x86_init.mapping.pagetable_reserve · 279b706b
      由 Stefano Stabellini 提交于 
      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 4b239f45
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: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      279b706b
  37. 15 2月, 2011 1 次提交
  39. 18 10月, 2010 1 次提交
  41. 08 7月, 2010 1 次提交
  43. 27 2月, 2010 1 次提交
    • R
      x86: Enable NMI on all cpus on UV · 78c06176
      由 Russ Anderson 提交于 
      Enable NMI on all cpus in UV system and add an NMI handler
to dump_stack on each cpu.

By default on x86 all the cpus except the boot cpu have NMI
masked off.  This patch enables NMI on all cpus in UV system
and adds an NMI handler to dump_stack on each cpu.  This
way if a system hangs we can NMI the machine and get a
backtrace from all the cpus.

Version 2: Use x86_platform driver mechanism for nmi init, per
           Ingo's suggestion.

Version 3: Clean up Ingo's nits.
Signed-off-by: NRuss Anderson <rja@sgi.com>
LKML-Reference: <20100226164912.GA24439@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      78c06176
  45. 26 2月, 2010 1 次提交
  47. 20 2月, 2010 2 次提交