linux-toradex.git/drivers/clocksource/arm_arch_timer.c, branch v5.1-rc4 Linux kernel for Apalis and Colibri modules Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm 2019-03-15T22:00:28+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-03-15T22:00:28+00:00 636deed6c0bc137a7c4f4a97ae1fcf0ad75323da Pull KVM updates from Paolo Bonzini: "ARM: - some cleanups - direct physical timer assignment - cache sanitization for 32-bit guests s390: - interrupt cleanup - introduction of the Guest Information Block - preparation for processor subfunctions in cpu models PPC: - bug fixes and improvements, especially related to machine checks and protection keys x86: - many, many cleanups, including removing a bunch of MMU code for unnecessary optimizations - AVIC fixes Generic: - memcg accounting" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (147 commits) kvm: vmx: fix formatting of a comment KVM: doc: Document the life cycle of a VM and its resources MAINTAINERS: Add KVM selftests to existing KVM entry Revert "KVM/MMU: Flush tlb directly in the kvm_zap_gfn_range()" KVM: PPC: Book3S: Add count cache flush parameters to kvmppc_get_cpu_char() KVM: PPC: Fix compilation when KVM is not enabled KVM: Minor cleanups for kvm_main.c KVM: s390: add debug logging for cpu model subfunctions KVM: s390: implement subfunction processor calls arm64: KVM: Fix architecturally invalid reset value for FPEXC32_EL2 KVM: arm/arm64: Remove unused timer variable KVM: PPC: Book3S: Improve KVM reference counting KVM: PPC: Book3S HV: Fix build failure without IOMMU support Revert "KVM: Eliminate extra function calls in kvm_get_dirty_log_protect()" x86: kvmguest: use TSC clocksource if invariant TSC is exposed KVM: Never start grow vCPU halt_poll_ns from value below halt_poll_ns_grow_start KVM: Expose the initial start value in grow_halt_poll_ns() as a module parameter KVM: grow_halt_poll_ns() should never shrink vCPU halt_poll_ns KVM: x86/mmu: Consolidate kvm_mmu_zap_all() and kvm_mmu_zap_mmio_sptes() KVM: x86/mmu: WARN if zapping a MMIO spte results in zapping children ... 
Pull KVM updates from Paolo Bonzini:
 "ARM:
   - some cleanups
   - direct physical timer assignment
   - cache sanitization for 32-bit guests

  s390:
   - interrupt cleanup
   - introduction of the Guest Information Block
   - preparation for processor subfunctions in cpu models

  PPC:
   - bug fixes and improvements, especially related to machine checks
     and protection keys

  x86:
   - many, many cleanups, including removing a bunch of MMU code for
     unnecessary optimizations
   - AVIC fixes

  Generic:
   - memcg accounting"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (147 commits)
  kvm: vmx: fix formatting of a comment
  KVM: doc: Document the life cycle of a VM and its resources
  MAINTAINERS: Add KVM selftests to existing KVM entry
  Revert "KVM/MMU: Flush tlb directly in the kvm_zap_gfn_range()"
  KVM: PPC: Book3S: Add count cache flush parameters to kvmppc_get_cpu_char()
  KVM: PPC: Fix compilation when KVM is not enabled
  KVM: Minor cleanups for kvm_main.c
  KVM: s390: add debug logging for cpu model subfunctions
  KVM: s390: implement subfunction processor calls
  arm64: KVM: Fix architecturally invalid reset value for FPEXC32_EL2
  KVM: arm/arm64: Remove unused timer variable
  KVM: PPC: Book3S: Improve KVM reference counting
  KVM: PPC: Book3S HV: Fix build failure without IOMMU support
  Revert "KVM: Eliminate extra function calls in kvm_get_dirty_log_protect()"
  x86: kvmguest: use TSC clocksource if invariant TSC is exposed
  KVM: Never start grow vCPU halt_poll_ns from value below halt_poll_ns_grow_start
  KVM: Expose the initial start value in grow_halt_poll_ns() as a module parameter
  KVM: grow_halt_poll_ns() should never shrink vCPU halt_poll_ns
  KVM: x86/mmu: Consolidate kvm_mmu_zap_all() and kvm_mmu_zap_mmio_sptes()
  KVM: x86/mmu: WARN if zapping a MMIO spte results in zapping children
  ...
clocksource/drivers/arch_timer: Workaround for Allwinner A64 timer instability 2019-02-23T11:13:45+00:00 Samuel Holland samuel@sholland.org 2019-01-13T02:17:18+00:00 c950ca8c35eeb32224a63adc47e12f9e226da241 The Allwinner A64 SoC is known[1] to have an unstable architectural timer, which manifests itself most obviously in the time jumping forward a multiple of 95 years[2][3]. This coincides with 2^56 cycles at a timer frequency of 24 MHz, implying that the time went slightly backward (and this was interpreted by the kernel as it jumping forward and wrapping around past the epoch). Investigation revealed instability in the low bits of CNTVCT at the point a high bit rolls over. This leads to power-of-two cycle forward and backward jumps. (Testing shows that forward jumps are about twice as likely as backward jumps.) Since the counter value returns to normal after an indeterminate read, each "jump" really consists of both a forward and backward jump from the software perspective. Unless the kernel is trapping CNTVCT reads, a userspace program is able to read the register in a loop faster than it changes. A test program running on all 4 CPU cores that reported jumps larger than 100 ms was run for 13.6 hours and reported the following: Count | Event -------+--------------------------- 9940 | jumped backward 699ms 268 | jumped backward 1398ms 1 | jumped backward 2097ms 16020 | jumped forward 175ms 6443 | jumped forward 699ms 2976 | jumped forward 1398ms 9 | jumped forward 356516ms 9 | jumped forward 357215ms 4 | jumped forward 714430ms 1 | jumped forward 3578440ms This works out to a jump larger than 100 ms about every 5.5 seconds on each CPU core. The largest jump (almost an hour!) was the following sequence of reads: 0x0000007fffffffff → 0x00000093feffffff → 0x0000008000000000 Note that the middle bits don't necessarily all read as all zeroes or all ones during the anomalous behavior; however the low 10 bits checked by the function in this patch have never been observed with any other value. Also note that smaller jumps are much more common, with backward jumps of 2048 (2^11) cycles observed over 400 times per second on each core. (Of course, this is partially explained by lower bits rolling over more frequently.) Any one of these could have caused the 95 year time skip. Similar anomalies were observed while reading CNTPCT (after patching the kernel to allow reads from userspace). However, the CNTPCT jumps are much less frequent, and only small jumps were observed. The same program as before (except now reading CNTPCT) observed after 72 hours: Count | Event -------+--------------------------- 17 | jumped backward 699ms 52 | jumped forward 175ms 2831 | jumped forward 699ms 5 | jumped forward 1398ms Further investigation showed that the instability in CNTPCT/CNTVCT also affected the respective timer's TVAL register. The following values were observed immediately after writing CNVT_TVAL to 0x10000000: CNTVCT | CNTV_TVAL | CNTV_CVAL | CNTV_TVAL Error --------------------+------------+--------------------+----------------- 0x000000d4a2d8bfff | 0x10003fff | 0x000000d4b2d8bfff | +0x00004000 0x000000d4a2d94000 | 0x0fffffff | 0x000000d4b2d97fff | -0x00004000 0x000000d4a2d97fff | 0x10003fff | 0x000000d4b2d97fff | +0x00004000 0x000000d4a2d9c000 | 0x0fffffff | 0x000000d4b2d9ffff | -0x00004000 The pattern of errors in CNTV_TVAL seemed to depend on exactly which value was written to it. For example, after writing 0x10101010: CNTVCT | CNTV_TVAL | CNTV_CVAL | CNTV_TVAL Error --------------------+------------+--------------------+----------------- 0x000001ac3effffff | 0x1110100f | 0x000001ac4f10100f | +0x1000000 0x000001ac40000000 | 0x1010100f | 0x000001ac5110100f | -0x1000000 0x000001ac58ffffff | 0x1110100f | 0x000001ac6910100f | +0x1000000 0x000001ac66000000 | 0x1010100f | 0x000001ac7710100f | -0x1000000 0x000001ac6affffff | 0x1110100f | 0x000001ac7b10100f | +0x1000000 0x000001ac6e000000 | 0x1010100f | 0x000001ac7f10100f | -0x1000000 I was also twice able to reproduce the issue covered by Allwinner's workaround[4], that writing to TVAL sometimes fails, and both CVAL and TVAL are left with entirely bogus values. One was the following values: CNTVCT | CNTV_TVAL | CNTV_CVAL --------------------+------------+-------------------------------------- 0x000000d4a2d6014c | 0x8fbd5721 | 0x000000d132935fff (615s in the past) Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> ======================================================================== Because the CPU can read the CNTPCT/CNTVCT registers faster than they change, performing two reads of the register and comparing the high bits (like other workarounds) is not a workable solution. And because the timer can jump both forward and backward, no pair of reads can distinguish a good value from a bad one. The only way to guarantee a good value from consecutive reads would be to read _three_ times, and take the middle value only if the three values are 1) each unique and 2) increasing. This takes at minimum 3 counter cycles (125 ns), or more if an anomaly is detected. However, since there is a distinct pattern to the bad values, we can optimize the common case (1022/1024 of the time) to a single read by simply ignoring values that match the error pattern. This still takes no more than 3 cycles in the worst case, and requires much less code. As an additional safety check, we still limit the loop iteration to the number of max-frequency (1.2 GHz) CPU cycles in three 24 MHz counter periods. For the TVAL registers, the simple solution is to not use them. Instead, read or write the CVAL and calculate the TVAL value in software. Although the manufacturer is aware of at least part of the erratum[4], there is no official name for it. For now, use the kernel-internal name "UNKNOWN1". [1]: https://github.com/armbian/build/commit/a08cd6fe7ae9 [2]: https://forum.armbian.com/topic/3458-a64-datetime-clock-issue/ [3]: https://irclog.whitequark.org/linux-sunxi/2018-01-26 [4]: https://github.com/Allwinner-Homlet/H6-BSP4.9-linux/blob/master/drivers/clocksource/arm_arch_timer.c#L272 Acked-by: Maxime Ripard <maxime.ripard@bootlin.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Samuel Holland <samuel@sholland.org> Cc: stable@vger.kernel.org Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> 
The Allwinner A64 SoC is known[1] to have an unstable architectural
timer, which manifests itself most obviously in the time jumping forward
a multiple of 95 years[2][3]. This coincides with 2^56 cycles at a
timer frequency of 24 MHz, implying that the time went slightly backward
(and this was interpreted by the kernel as it jumping forward and
wrapping around past the epoch).

Investigation revealed instability in the low bits of CNTVCT at the
point a high bit rolls over. This leads to power-of-two cycle forward
and backward jumps. (Testing shows that forward jumps are about twice as
likely as backward jumps.) Since the counter value returns to normal
after an indeterminate read, each "jump" really consists of both a
forward and backward jump from the software perspective.

Unless the kernel is trapping CNTVCT reads, a userspace program is able
to read the register in a loop faster than it changes. A test program
running on all 4 CPU cores that reported jumps larger than 100 ms was
run for 13.6 hours and reported the following:

 Count | Event
-------+---------------------------
  9940 | jumped backward      699ms
   268 | jumped backward     1398ms
     1 | jumped backward     2097ms
 16020 | jumped forward       175ms
  6443 | jumped forward       699ms
  2976 | jumped forward      1398ms
     9 | jumped forward    356516ms
     9 | jumped forward    357215ms
     4 | jumped forward    714430ms
     1 | jumped forward   3578440ms

This works out to a jump larger than 100 ms about every 5.5 seconds on
each CPU core.

The largest jump (almost an hour!) was the following sequence of reads:
    0x0000007fffffffff → 0x00000093feffffff → 0x0000008000000000

Note that the middle bits don't necessarily all read as all zeroes or
all ones during the anomalous behavior; however the low 10 bits checked
by the function in this patch have never been observed with any other
value.

Also note that smaller jumps are much more common, with backward jumps
of 2048 (2^11) cycles observed over 400 times per second on each core.
(Of course, this is partially explained by lower bits rolling over more
frequently.) Any one of these could have caused the 95 year time skip.

Similar anomalies were observed while reading CNTPCT (after patching the
kernel to allow reads from userspace). However, the CNTPCT jumps are
much less frequent, and only small jumps were observed. The same program
as before (except now reading CNTPCT) observed after 72 hours:

 Count | Event
-------+---------------------------
    17 | jumped backward      699ms
    52 | jumped forward       175ms
  2831 | jumped forward       699ms
     5 | jumped forward      1398ms

Further investigation showed that the instability in CNTPCT/CNTVCT also
affected the respective timer's TVAL register. The following values were
observed immediately after writing CNVT_TVAL to 0x10000000:

 CNTVCT             | CNTV_TVAL  | CNTV_CVAL          | CNTV_TVAL Error
--------------------+------------+--------------------+-----------------
 0x000000d4a2d8bfff | 0x10003fff | 0x000000d4b2d8bfff | +0x00004000
 0x000000d4a2d94000 | 0x0fffffff | 0x000000d4b2d97fff | -0x00004000
 0x000000d4a2d97fff | 0x10003fff | 0x000000d4b2d97fff | +0x00004000
 0x000000d4a2d9c000 | 0x0fffffff | 0x000000d4b2d9ffff | -0x00004000

The pattern of errors in CNTV_TVAL seemed to depend on exactly which
value was written to it. For example, after writing 0x10101010:

 CNTVCT             | CNTV_TVAL  | CNTV_CVAL          | CNTV_TVAL Error
--------------------+------------+--------------------+-----------------
 0x000001ac3effffff | 0x1110100f | 0x000001ac4f10100f | +0x1000000
 0x000001ac40000000 | 0x1010100f | 0x000001ac5110100f | -0x1000000
 0x000001ac58ffffff | 0x1110100f | 0x000001ac6910100f | +0x1000000
 0x000001ac66000000 | 0x1010100f | 0x000001ac7710100f | -0x1000000
 0x000001ac6affffff | 0x1110100f | 0x000001ac7b10100f | +0x1000000
 0x000001ac6e000000 | 0x1010100f | 0x000001ac7f10100f | -0x1000000

I was also twice able to reproduce the issue covered by Allwinner's
workaround[4], that writing to TVAL sometimes fails, and both CVAL and
TVAL are left with entirely bogus values. One was the following values:

 CNTVCT             | CNTV_TVAL  | CNTV_CVAL
--------------------+------------+--------------------------------------
 0x000000d4a2d6014c | 0x8fbd5721 | 0x000000d132935fff (615s in the past)
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>

========================================================================

Because the CPU can read the CNTPCT/CNTVCT registers faster than they
change, performing two reads of the register and comparing the high bits
(like other workarounds) is not a workable solution. And because the
timer can jump both forward and backward, no pair of reads can
distinguish a good value from a bad one. The only way to guarantee a
good value from consecutive reads would be to read _three_ times, and
take the middle value only if the three values are 1) each unique and
2) increasing. This takes at minimum 3 counter cycles (125 ns), or more
if an anomaly is detected.

However, since there is a distinct pattern to the bad values, we can
optimize the common case (1022/1024 of the time) to a single read by
simply ignoring values that match the error pattern. This still takes no
more than 3 cycles in the worst case, and requires much less code. As an
additional safety check, we still limit the loop iteration to the number
of max-frequency (1.2 GHz) CPU cycles in three 24 MHz counter periods.

For the TVAL registers, the simple solution is to not use them. Instead,
read or write the CVAL and calculate the TVAL value in software.

Although the manufacturer is aware of at least part of the erratum[4],
there is no official name for it. For now, use the kernel-internal name
"UNKNOWN1".

[1]: https://github.com/armbian/build/commit/a08cd6fe7ae9
[2]: https://forum.armbian.com/topic/3458-a64-datetime-clock-issue/
[3]: https://irclog.whitequark.org/linux-sunxi/2018-01-26
[4]: https://github.com/Allwinner-Homlet/H6-BSP4.9-linux/blob/master/drivers/clocksource/arm_arch_timer.c#L272

Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
clocksource/arm_arch_timer: Store physical timer IRQ number for KVM on VHE 2019-02-19T21:05:22+00:00 Andre Przywara andre.przywara@arm.com 2018-07-06T08:11:50+00:00 ee7930490a8f84570e96268f5736e99570b58307 A host running in VHE mode gets the EL2 physical timer as its time source (accessed using the EL1 sysreg accessors, which get re-directed to the EL2 sysregs by VHE). The EL1 physical timer remains unused by the host kernel, allowing us to pass that on directly to a KVM guest and saves us from emulating this timer for the guest on VHE systems. Store the EL1 Physical Timer's IRQ number in struct arch_timer_kvm_info on VHE systems to allow KVM to use it. Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@arm.com> 
A host running in VHE mode gets the EL2 physical timer as its time
source (accessed using the EL1 sysreg accessors, which get re-directed
to the EL2 sysregs by VHE).

The EL1 physical timer remains unused by the host kernel, allowing us to
pass that on directly to a KVM guest and saves us from emulating this
timer for the guest on VHE systems.

Store the EL1 Physical Timer's IRQ number in
struct arch_timer_kvm_info on VHE systems to allow KVM to use it.

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
arm64: arch_timer: Add workaround for ARM erratum 1188873 2018-10-01T12:38:47+00:00 Marc Zyngier marc.zyngier@arm.com 2018-09-27T16:15:34+00:00 95b861a4a6d94f64d5242605569218160ebacdbe When running on Cortex-A76, a timer access from an AArch32 EL0 task may end up with a corrupted value or register. The workaround for this is to trap these accesses at EL1/EL2 and execute them there. This only affects versions r0p0, r1p0 and r2p0 of the CPU. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
When running on Cortex-A76, a timer access from an AArch32 EL0
task may end up with a corrupted value or register. The workaround for
this is to trap these accesses at EL1/EL2 and execute them there.

This only affects versions r0p0, r1p0 and r2p0 of the CPU.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
clocksource: arm_arch_timer: Set arch_mem_timer cpumask to cpu_possible_mask 2018-07-10T20:12:47+00:00 Sudeep Holla sudeep.holla@arm.com 2018-07-09T15:45:36+00:00 5e18e412973d6bb1804de1d4d30a891c774b006e Currently, arch_mem_timer cpumask is set to cpu_all_mask which should be fine. However, cpu_possible_mask is more accurate and if there are other clockevent source in the system which are set to cpu_possible_mask, then having cpu_all_mask may result in issue. E.g. on a platform with arm,sp804 timer with rating 300 and cpu_possible_mask and this arch_mem_timer timer with rating 400 and cpu_all_mask, tick_check_preferred may choose both preferred as the cpumasks are not equal though they must be. This issue was root caused incorrectly initially and a fix was merged as commit 1332a9055801 ("tick: Prefer a lower rating device only if it's CPU local device"). Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kevin Hilman <khilman@baylibre.com> Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Cc: linux-arm-kernel@lists.infradead.org Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Link: https://lkml.kernel.org/r/1531151136-18297-2-git-send-email-sudeep.holla@arm.com 
Currently, arch_mem_timer cpumask is set to cpu_all_mask which should be
fine. However, cpu_possible_mask is more accurate and if there are other
clockevent source in the system which are set to cpu_possible_mask, then
having cpu_all_mask may result in issue.

E.g. on a platform with arm,sp804 timer with rating 300 and
cpu_possible_mask and this arch_mem_timer timer with rating 400 and
cpu_all_mask, tick_check_preferred may choose both preferred as the
cpumasks are not equal though they must be.

This issue was root caused incorrectly initially and a fix was merged as
commit 1332a9055801 ("tick: Prefer a lower rating device only if it's CPU
local device").

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/1531151136-18297-2-git-send-email-sudeep.holla@arm.com
Merge tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm 2017-11-16T21:00:24+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-11-16T21:00:24+00:00 974aa5630b318938273d7efe7a2cf031c7b927db Pull KVM updates from Radim Krčmář: "First batch of KVM changes for 4.15 Common: - Python 3 support in kvm_stat - Accounting of slabs to kmemcg ARM: - Optimized arch timer handling for KVM/ARM - Improvements to the VGIC ITS code and introduction of an ITS reset ioctl - Unification of the 32-bit fault injection logic - More exact external abort matching logic PPC: - Support for running hashed page table (HPT) MMU mode on a host that is using the radix MMU mode; single threaded mode on POWER 9 is added as a pre-requisite - Resolution of merge conflicts with the last second 4.14 HPT fixes - Fixes and cleanups s390: - Some initial preparation patches for exitless interrupts and crypto - New capability for AIS migration - Fixes x86: - Improved emulation of LAPIC timer mode changes, MCi_STATUS MSRs, and after-reset state - Refined dependencies for VMX features - Fixes for nested SMI injection - A lot of cleanups" * tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (89 commits) KVM: s390: provide a capability for AIS state migration KVM: s390: clear_io_irq() requests are not expected for adapter interrupts KVM: s390: abstract conversion between isc and enum irq_types KVM: s390: vsie: use common code functions for pinning KVM: s390: SIE considerations for AP Queue virtualization KVM: s390: document memory ordering for kvm_s390_vcpu_wakeup KVM: PPC: Book3S HV: Cosmetic post-merge cleanups KVM: arm/arm64: fix the incompatible matching for external abort KVM: arm/arm64: Unify 32bit fault injection KVM: arm/arm64: vgic-its: Implement KVM_DEV_ARM_ITS_CTRL_RESET KVM: arm/arm64: Document KVM_DEV_ARM_ITS_CTRL_RESET KVM: arm/arm64: vgic-its: Free caches when GITS_BASER Valid bit is cleared KVM: arm/arm64: vgic-its: New helper functions to free the caches KVM: arm/arm64: vgic-its: Remove kvm_its_unmap_device arm/arm64: KVM: Load the timer state when enabling the timer KVM: arm/arm64: Rework kvm_timer_should_fire KVM: arm/arm64: Get rid of kvm_timer_flush_hwstate KVM: arm/arm64: Avoid phys timer emulation in vcpu entry/exit KVM: arm/arm64: Move phys_timer_emulate function KVM: arm/arm64: Use kvm_arm_timer_set/get_reg for guest register traps ... 
Pull KVM updates from Radim Krčmář:
 "First batch of KVM changes for 4.15

  Common:
   - Python 3 support in kvm_stat
   - Accounting of slabs to kmemcg

  ARM:
   - Optimized arch timer handling for KVM/ARM
   - Improvements to the VGIC ITS code and introduction of an ITS reset
     ioctl
   - Unification of the 32-bit fault injection logic
   - More exact external abort matching logic

  PPC:
   - Support for running hashed page table (HPT) MMU mode on a host that
     is using the radix MMU mode; single threaded mode on POWER 9 is
     added as a pre-requisite
   - Resolution of merge conflicts with the last second 4.14 HPT fixes
   - Fixes and cleanups

  s390:
   - Some initial preparation patches for exitless interrupts and crypto
   - New capability for AIS migration
   - Fixes

  x86:
   - Improved emulation of LAPIC timer mode changes, MCi_STATUS MSRs,
     and after-reset state
   - Refined dependencies for VMX features
   - Fixes for nested SMI injection
   - A lot of cleanups"

* tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (89 commits)
  KVM: s390: provide a capability for AIS state migration
  KVM: s390: clear_io_irq() requests are not expected for adapter interrupts
  KVM: s390: abstract conversion between isc and enum irq_types
  KVM: s390: vsie: use common code functions for pinning
  KVM: s390: SIE considerations for AP Queue virtualization
  KVM: s390: document memory ordering for kvm_s390_vcpu_wakeup
  KVM: PPC: Book3S HV: Cosmetic post-merge cleanups
  KVM: arm/arm64: fix the incompatible matching for external abort
  KVM: arm/arm64: Unify 32bit fault injection
  KVM: arm/arm64: vgic-its: Implement KVM_DEV_ARM_ITS_CTRL_RESET
  KVM: arm/arm64: Document KVM_DEV_ARM_ITS_CTRL_RESET
  KVM: arm/arm64: vgic-its: Free caches when GITS_BASER Valid bit is cleared
  KVM: arm/arm64: vgic-its: New helper functions to free the caches
  KVM: arm/arm64: vgic-its: Remove kvm_its_unmap_device
  arm/arm64: KVM: Load the timer state when enabling the timer
  KVM: arm/arm64: Rework kvm_timer_should_fire
  KVM: arm/arm64: Get rid of kvm_timer_flush_hwstate
  KVM: arm/arm64: Avoid phys timer emulation in vcpu entry/exit
  KVM: arm/arm64: Move phys_timer_emulate function
  KVM: arm/arm64: Use kvm_arm_timer_set/get_reg for guest register traps
  ...
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux 2017-11-15T18:56:56+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-11-15T18:56:56+00:00 c9b012e5f4a1d01dfa8abc6318211a67ba7d5db2 Pull arm64 updates from Will Deacon: "The big highlight is support for the Scalable Vector Extension (SVE) which required extensive ABI work to ensure we don't break existing applications by blowing away their signal stack with the rather large new vector context (<= 2 kbit per vector register). There's further work to be done optimising things like exception return, but the ABI is solid now. Much of the line count comes from some new PMU drivers we have, but they're pretty self-contained and I suspect we'll have more of them in future. Plenty of acronym soup here: - initial support for the Scalable Vector Extension (SVE) - improved handling for SError interrupts (required to handle RAS events) - enable GCC support for 128-bit integer types - remove kernel text addresses from backtraces and register dumps - use of WFE to implement long delay()s - ACPI IORT updates from Lorenzo Pieralisi - perf PMU driver for the Statistical Profiling Extension (SPE) - perf PMU driver for Hisilicon's system PMUs - misc cleanups and non-critical fixes" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (97 commits) arm64: Make ARMV8_DEPRECATED depend on SYSCTL arm64: Implement __lshrti3 library function arm64: support __int128 on gcc 5+ arm64/sve: Add documentation arm64/sve: Detect SVE and activate runtime support arm64/sve: KVM: Hide SVE from CPU features exposed to guests arm64/sve: KVM: Treat guest SVE use as undefined instruction execution arm64/sve: KVM: Prevent guests from using SVE arm64/sve: Add sysctl to set the default vector length for new processes arm64/sve: Add prctl controls for userspace vector length management arm64/sve: ptrace and ELF coredump support arm64/sve: Preserve SVE registers around EFI runtime service calls arm64/sve: Preserve SVE registers around kernel-mode NEON use arm64/sve: Probe SVE capabilities and usable vector lengths arm64: cpufeature: Move sys_caps_initialised declarations arm64/sve: Backend logic for setting the vector length arm64/sve: Signal handling support arm64/sve: Support vector length resetting for new processes arm64/sve: Core task context handling arm64/sve: Low-level CPU setup ... 
Pull arm64 updates from Will Deacon:
 "The big highlight is support for the Scalable Vector Extension (SVE)
  which required extensive ABI work to ensure we don't break existing
  applications by blowing away their signal stack with the rather large
  new vector context (<= 2 kbit per vector register). There's further
  work to be done optimising things like exception return, but the ABI
  is solid now.

  Much of the line count comes from some new PMU drivers we have, but
  they're pretty self-contained and I suspect we'll have more of them in
  future.

  Plenty of acronym soup here:

   - initial support for the Scalable Vector Extension (SVE)

   - improved handling for SError interrupts (required to handle RAS
     events)

   - enable GCC support for 128-bit integer types

   - remove kernel text addresses from backtraces and register dumps

   - use of WFE to implement long delay()s

   - ACPI IORT updates from Lorenzo Pieralisi

   - perf PMU driver for the Statistical Profiling Extension (SPE)

   - perf PMU driver for Hisilicon's system PMUs

   - misc cleanups and non-critical fixes"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (97 commits)
  arm64: Make ARMV8_DEPRECATED depend on SYSCTL
  arm64: Implement __lshrti3 library function
  arm64: support __int128 on gcc 5+
  arm64/sve: Add documentation
  arm64/sve: Detect SVE and activate runtime support
  arm64/sve: KVM: Hide SVE from CPU features exposed to guests
  arm64/sve: KVM: Treat guest SVE use as undefined instruction execution
  arm64/sve: KVM: Prevent guests from using SVE
  arm64/sve: Add sysctl to set the default vector length for new processes
  arm64/sve: Add prctl controls for userspace vector length management
  arm64/sve: ptrace and ELF coredump support
  arm64/sve: Preserve SVE registers around EFI runtime service calls
  arm64/sve: Preserve SVE registers around kernel-mode NEON use
  arm64/sve: Probe SVE capabilities and usable vector lengths
  arm64: cpufeature: Move sys_caps_initialised declarations
  arm64/sve: Backend logic for setting the vector length
  arm64/sve: Signal handling support
  arm64/sve: Support vector length resetting for new processes
  arm64/sve: Core task context handling
  arm64/sve: Low-level CPU setup
  ...
arm64: Use physical counter for in-kernel reads when booted in EL2 2017-11-06T15:23:09+00:00 Christoffer Dall cdall@linaro.org 2017-07-05T09:04:28+00:00 e6d68b00e989f27116fd8575f1f9c217873e9b0e Using the physical counter allows KVM to retain the offset between the virtual and physical counter as long as it is actively running a VCPU. As soon as a VCPU is released, another thread is scheduled or we start running userspace applications, we reset the offset to 0, so that userspace accessing the virtual timer can still read the virtual counter and get the same view of time as the kernel. This opens up potential improvements for KVM performance, but we have to make a few adjustments to preserve system consistency. Currently get_cycles() is hardwired to arch_counter_get_cntvct() on arm64, but as we move to using the physical timer for the in-kernel time-keeping on systems that boot in EL2, we should use the same counter for get_cycles() as for other in-kernel timekeeping operations. Similarly, implementations of arch_timer_set_next_event_phys() is modified to use the counter specific to the timer being programmed. VHE kernels or kernels continuing to use the virtual timer are unaffected. Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <cdall@linaro.org> 
Using the physical counter allows KVM to retain the offset between the
virtual and physical counter as long as it is actively running a VCPU.

As soon as a VCPU is released, another thread is scheduled or we start
running userspace applications, we reset the offset to 0, so that
userspace accessing the virtual timer can still read the virtual counter
and get the same view of time as the kernel.

This opens up potential improvements for KVM performance, but we have to
make a few adjustments to preserve system consistency.

Currently get_cycles() is hardwired to arch_counter_get_cntvct() on
arm64, but as we move to using the physical timer for the in-kernel
time-keeping on systems that boot in EL2, we should use the same counter
for get_cycles() as for other in-kernel timekeeping operations.

Similarly, implementations of arch_timer_set_next_event_phys() is
modified to use the counter specific to the timer being programmed.

VHE kernels or kernels continuing to use the virtual timer are
unaffected.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
arm64: Implement arch_counter_get_cntpct to read the physical counter 2017-11-06T15:23:08+00:00 Christoffer Dall christoffer.dall@linaro.org 2017-10-18T11:06:25+00:00 f2e600c149fda3453344f89c7e9353fe278ebd32 As we are about to use the physical counter on arm64 systems that have KVM support, implement arch_counter_get_cntpct() and the associated errata workaround functionality for stable timer reads. Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> 
As we are about to use the physical counter on arm64 systems that have
KVM support, implement arch_counter_get_cntpct() and the associated
errata workaround functionality for stable timer reads.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
clocksource/drivers/arm_arch_timer: Fix DEFINE_PER_CPU expansion 2017-10-19T21:49:06+00:00 Mark Rutland mark.rutland@arm.com 2017-10-16T15:28:39+00:00 a7fb4577bbe307dd3dd971c7ea8f35a68fc031ca Our ctags mangling script can't handle newlines inside of a DEFINE_PER_CPU(), leading to an annoying message whenever tags are built: ctags: Warning: drivers/clocksource/arm_arch_timer.c:302: null expansion of name pattern "\1" This was dealt with elsewhere in commit: 25528213fe9f75f4 ("tags: Fix DEFINE_PER_CPU expansions") ... by ensuring each DEFINE_PER_CPU() was contained on a single line, even where this would violate the usual code style (checkpatch warnings and all). Let's do the same for the arch timer driver, and get rid of the distraction. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> 
Our ctags mangling script can't handle newlines inside of a
DEFINE_PER_CPU(), leading to an annoying message whenever tags are
built:

  ctags: Warning: drivers/clocksource/arm_arch_timer.c:302: null expansion of name pattern "\1"

This was dealt with elsewhere in commit:

  25528213fe9f75f4 ("tags: Fix DEFINE_PER_CPU expansions")

... by ensuring each DEFINE_PER_CPU() was contained on a single line,
even where this would violate the usual code style (checkpatch warnings
and all).

Let's do the same for the arch timer driver, and get rid of the
distraction.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>