Commit Graph

4 Commits

Author SHA1 Message Date
Linus Torvalds
412d070b31 ARM:
* Correctly save/restore PMUSERNR_EL0 when host userspace is using
   PMU counters directly
 
 * Fix GICv2 emulation on GICv3 after the locking rework
 
 * Don't use smp_processor_id() in kvm_pmu_probe_armpmu(), and
   document why
 
 Generic:
 
 * Avoid setting page table entries pointing to a deleted memslot if a
   host page table entry is changed concurrently with the deletion.
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmSUoQoUHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroP6swf5ATU/csLrT1gR5v+YkXmlUUUi4423
 VceijG7Y2+XSH7dk9svf1WLLi4OTvxs4WfUEEnFPmEXMx9PkL+btaACcXfVjpolA
 dD6RsPk6fZ8XOpVkjuWENFJtstm9jOUQIZeEShvIKRabHRFHAPlmYF6LJ67S/j+E
 iK/8ScnAHznbsGlN+HhLhwpLxzkam09ZwpXt9eT1ZNev7E8FAnYI9nGGxz6UIqAW
 WHWJIyMpYpXZYsNuHXDMUAvn1TCpkKM0i38NEll0qEUktI9pW3cmm3kOSAlVe+47
 V3LMtAP0v2VC938VAPsXBZgDlVr7yfEqzb73VBGd9776QDK3b6rjF1ZDYA==
 =fuod
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "ARM:

   - Correctly save/restore PMUSERNR_EL0 when host userspace is using
     PMU counters directly

   - Fix GICv2 emulation on GICv3 after the locking rework

   - Don't use smp_processor_id() in kvm_pmu_probe_armpmu(), and
     document why

  Generic:

   - Avoid setting page table entries pointing to a deleted memslot if a
     host page table entry is changed concurrently with the deletion"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: Avoid illegal stage2 mapping on invalid memory slot
  KVM: arm64: Use raw_smp_processor_id() in kvm_pmu_probe_armpmu()
  KVM: arm64: Restore GICv2-on-GICv3 functionality
  KVM: arm64: PMU: Don't overwrite PMUSERENR with vcpu loaded
  KVM: arm64: PMU: Restore the host's PMUSERENR_EL0
2023-06-22 17:54:10 -07:00
Reiji Watanabe
0c2f9acf6a KVM: arm64: PMU: Don't overwrite PMUSERENR with vcpu loaded
Currently, with VHE, KVM sets ER, CR, SW and EN bits of
PMUSERENR_EL0 to 1 on vcpu_load(), and saves and restores
the register value for the host on vcpu_load() and vcpu_put().
If the value of those bits are cleared on a pCPU with a vCPU
loaded (armv8pmu_start() would do that when PMU counters are
programmed for the guest), PMU access from the guest EL0 might
be trapped to the guest EL1 directly regardless of the current
PMUSERENR_EL0 value of the vCPU.

Fix this by not letting armv8pmu_start() overwrite PMUSERENR_EL0
on the pCPU where PMUSERENR_EL0 for the guest is loaded, and
instead updating the saved shadow register value for the host
so that the value can be restored on vcpu_put() later.
While vcpu_{put,load}() are manipulating PMUSERENR_EL0, disable
IRQs to prevent a race condition between these processes and IPIs
that attempt to update PMUSERENR_EL0 for the host EL0.

Suggested-by: Mark Rutland <mark.rutland@arm.com>
Suggested-by: Marc Zyngier <maz@kernel.org>
Fixes: 83a7a4d643 ("arm64: perf: Enable PMU counter userspace access for perf event")
Signed-off-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230603025035.3781797-3-reijiw@google.com
2023-06-04 17:19:36 +01:00
Geert Uytterhoeven
68e3f61eb9 ARM: perf: Mark all accessor functions inline
When just including <asm/arm_pmuv3.h>:

    arch/arm/include/asm/arm_pmuv3.h:110:13: error: ‘write_pmevtypern’ defined but not used [-Werror=unused-function]
      110 | static void write_pmevtypern(int n, unsigned long val)
	  |             ^~~~~~~~~~~~~~~~
    arch/arm/include/asm/arm_pmuv3.h:103:13: error: ‘write_pmevcntrn’ defined but not used [-Werror=unused-function]
      103 | static void write_pmevcntrn(int n, unsigned long val)
	  |             ^~~~~~~~~~~~~~~
    arch/arm/include/asm/arm_pmuv3.h:95:22: error: ‘read_pmevcntrn’ defined but not used [-Werror=unused-function]
       95 | static unsigned long read_pmevcntrn(int n)
	  |                      ^~~~~~~~~~~~~~

Fix this by adding the missing "inline" keywords to the three accessor
functions that lack them.

Fixes: 009d6dc87a ("ARM: perf: Allow the use of the PMUv3 driver on 32bit ARM")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/3a7d9bc7470aa2d85696ee9765c74f8c03fb5454.1683561482.git.geert+renesas@glider.be
Signed-off-by: Will Deacon <will@kernel.org>
2023-05-16 14:57:29 +01:00
Marc Zyngier
009d6dc87a ARM: perf: Allow the use of the PMUv3 driver on 32bit ARM
The only thing stopping the PMUv3 driver from compiling on 32bit
is the lack of defined system registers names and the handful of
required helpers.

This is easily solved by providing the sysreg accessors and updating
the Kconfig entry.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Co-developed-by: Zaid Al-Bassam <zalbassam@google.com>
Signed-off-by: Zaid Al-Bassam <zalbassam@google.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20230317195027.3746949-8-zalbassam@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-03-27 14:01:18 +01:00