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Linux kernel
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Pll KVM fixes from Radim Krčmář:
"ARM:
- Fix proxying of GICv2 CPU interface accesses
- Fix crash when switching to BE
- Track source vcpu git GICv2 SGIs
- Fix an outdated bit of documentation
x86:
- Speed up injection of expired timers (for stable)"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: remove APIC Timer periodic/oneshot spikes
arm64: vgic-v2: Fix proxying of cpuif access
KVM: arm/arm64: vgic_init: Cleanup reference to process_maintenance
KVM: arm64: Fix order of vcpu_write_sys_reg() arguments
KVM: arm/arm64: vgic: Fix source vcpu issues for GICv2 SGI
Pull iommu fixes from Joerg Roedel:
- fix a compile warning in the AMD IOMMU driver with irq remapping
disabled
- fix for VT-d interrupt remapping and invalidation size (caused a
BUG_ON when trying to invalidate more than 4GB)
- build fix and a regression fix for broken graphics with old DTS for
the rockchip iommu driver
- a revert in the PCI window reservation code which fixes a regression
with VFIO.
* tag 'iommu-fixes-v4.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu: rockchip: fix building without CONFIG_OF
iommu/vt-d: Use WARN_ON_ONCE instead of BUG_ON in qi_flush_dev_iotlb()
iommu/vt-d: fix shift-out-of-bounds in bug checking
iommu/dma: Move PCI window region reservation back into dma specific path.
iommu/rockchip: Make clock handling optional
iommu/amd: Hide unused iommu_table_lock
iommu/vt-d: Fix usage of force parameter in intel_ir_reconfigure_irte()
Since the commit "8003c9ae204e: add APIC Timer periodic/oneshot mode VMX
preemption timer support", a Windows 10 guest has some erratic timer
spikes.
Here the results on a 150000 times 1ms timer without any load:
Before 8003c9ae204e | After 8003c9ae204e
Max 1834us | 86000us
Mean 1100us | 1021us
Deviation 59us | 149us
Here the results on a 150000 times 1ms timer with a cpu-z stress test:
Before 8003c9ae204e | After 8003c9ae204e
Max 32000us | 140000us
Mean 1006us | 1997us
Deviation 140us | 11095us
The root cause of the problem is starting hrtimer with an expiry time
already in the past can take more than 20 milliseconds to trigger the
timer function. It can be solved by forward such past timers
immediately, rather than submitting them to hrtimer_start().
In case the timer is periodic, update the target expiration and call
hrtimer_start with it.
v2: Check if the tsc deadline is already expired. Thank you Mika.
v3: Execute the past timers immediately rather than submitting them to
hrtimer_start().
v4: Rearm the periodic timer with advance_periodic_target_expiration() a
simpler version of set_target_expiration(). Thank you Paolo.
Cc: Mika Penttilä <mika.penttila@nextfour.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Anthoine Bourgeois <anthoine.bourgeois@blade-group.com>
8003c9ae204e ("KVM: LAPIC: add APIC Timer periodic/oneshot mode VMX preemption timer support")
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Pull x86 fix from Thomas Gleixner:
"Unbreak the CPUID CPUID_8000_0008_EBX reload which got dropped when
the evaluation of physical and virtual bits which uses the same CPUID
leaf was moved out of get_cpu_cap()"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Restore CPUID_8000_0008_EBX reload
We get a build error when compiling the iommu driver without CONFIG_OF:
drivers/iommu/rockchip-iommu.c: In function 'rk_iommu_of_xlate':
drivers/iommu/rockchip-iommu.c:1101:2: error: implicit declaration of function 'of_dev_put'; did you mean 'of_node_put'? [-Werror=implicit-function-declaration]
This replaces the of_dev_put() with the equivalent
platform_device_put().
Fixes: 5fd577c3eac3 ("iommu/rockchip: Use OF_IOMMU to attach devices automatically")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
KVM/arm fixes for 4.17, take #2
- Fix proxying of GICv2 CPU interface accesses
- Fix crash when switching to BE
- Track source vcpu git GICv2 SGIs
- Fix an outdated bit of documentation
Pull clocksource fixes from Thomas Gleixner:
"The recent addition of the early TSC clocksource breaks on machines
which have an unstable TSC because in case that TSC is disabled, then
the clocksource selection logic falls back to the early TSC which is
obviously bogus.
That also unearthed a few robustness issues in the clocksource
derating code which are addressed as well"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
clocksource: Rework stale comment
clocksource: Consistent de-rate when marking unstable
x86/tsc: Fix mark_tsc_unstable()
clocksource: Initialize cs->wd_list
clocksource: Allow clocksource_mark_unstable() on unregistered clocksources
x86/tsc: Always unregister clocksource_tsc_early
The recent commt which addresses the x86_phys_bits corruption with
encrypted memory on CPUID reload after a microcode update lost the reload
of CPUID_8000_0008_EBX as well.
As a consequence IBRS and IBRS_FW are not longer detected
Restore the behaviour by bringing the reload of CPUID_8000_0008_EBX
back. This restore has a twist due to the convoluted way the cpuid analysis
works:
CPUID_8000_0008_EBX is used by AMD to enumerate IBRB, IBRS, STIBP. On Intel
EBX is not used. But the speculation control code sets the AMD bits when
running on Intel depending on the Intel specific speculation control
bits. This was done to use the same bits for alternatives.
The change which moved the 8000_0008 evaluation out of get_cpu_cap() broke
this nasty scheme due to ordering. So that on Intel the store to
CPUID_8000_0008_EBX clears the IBRB, IBRS, STIBP bits which had been set
before by software.
So the actual CPUID_8000_0008_EBX needs to go back to the place where it
was and the phys/virt address space calculation cannot touch it.
In hindsight this should have used completely synthetic bits for IBRB,
IBRS, STIBP instead of reusing the AMD bits, but that's for 4.18.
/me needs to find time to cleanup that steaming pile of ...
Fixes: d94a155c59c9 ("x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption")
Reported-by: Jörg Otte <jrg.otte@gmail.com>
Reported-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jörg Otte <jrg.otte@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: kirill.shutemov@linux.intel.com
Cc: Borislav Petkov <bp@alien8.de
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1805021043510.1668@nanos.tec.linutronix.de
A misaligned address is only worth a warning, and not
stopping the while execution path with a BUG_ON().
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Proxying the cpuif accesses at EL2 makes use of vcpu_data_guest_to_host
and co, which check the endianness, which call into vcpu_read_sys_reg...
which isn't mapped at EL2 (it was inlined before, and got moved OoL
with the VHE optimizations).
The result is of course a nice panic. Let's add some specialized
cruft to keep the broken platforms that require this hack alive.
But, this code used vcpu_data_guest_to_host(), which expected us to
write the value to host memory, instead we have trapped the guest's
read or write to an mmio-device, and are about to replay it using the
host's readl()/writel() which also perform swabbing based on the host
endianness. This goes wrong when both host and guest are big-endian,
as readl()/writel() will undo the guest's swabbing, causing the
big-endian value to be written to device-memory.
What needs doing?
A big-endian guest will have pre-swabbed data before storing, undo this.
If its necessary for the host, writel() will re-swab it.
For a read a big-endian guest expects to swab the data after the load.
The hosts's readl() will correct for host endianness, giving us the
device-memory's value in the register. For a big-endian guest, swab it
as if we'd only done the load.
For a little-endian guest, nothing needs doing as readl()/writel() leave
the correct device-memory value in registers.
Tested on Juno with that rarest of things: a big-endian 64K host.
Based on a patch from Marc Zyngier.
Reported-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Fixes: bf8feb39642b ("arm64: KVM: vgic-v2: Add GICV access from HYP")
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Pull irq fix from Thomas Gleixner:
"A single fix to prevent false positives in the spurious interrupt
detector when more than a single demultiplex register is evaluated in
the Qualcom irq combiner driver"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/qcom: Fix check for spurious interrupts
AFAICS the hotplug code no longer uses this function.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: len.brown@intel.com
Cc: rjw@rjwysocki.net
Cc: diego.viola@gmail.com
Cc: rui.zhang@intel.com
Link: https://lkml.kernel.org/r/20180430100344.656525644@infradead.org
It allows to flush more than 4GB of device TLBs. So the mask should be
64bit wide. UBSAN captured this fault as below.
[ 3.760024] ================================================================================
[ 3.768440] UBSAN: Undefined behaviour in drivers/iommu/dmar.c:1348:3
[ 3.774864] shift exponent 64 is too large for 32-bit type 'int'
[ 3.780853] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G U 4.17.0-rc1+ #89
[ 3.788661] Hardware name: Dell Inc. OptiPlex 7040/0Y7WYT, BIOS 1.2.8 01/26/2016
[ 3.796034] Call Trace:
[ 3.798472] <IRQ>
[ 3.800479] dump_stack+0x90/0xfb
[ 3.803787] ubsan_epilogue+0x9/0x40
[ 3.807353] __ubsan_handle_shift_out_of_bounds+0x10e/0x170
[ 3.812916] ? qi_flush_dev_iotlb+0x124/0x180
[ 3.817261] qi_flush_dev_iotlb+0x124/0x180
[ 3.821437] iommu_flush_dev_iotlb+0x94/0xf0
[ 3.825698] iommu_flush_iova+0x10b/0x1c0
[ 3.829699] ? fq_ring_free+0x1d0/0x1d0
[ 3.833527] iova_domain_flush+0x25/0x40
[ 3.837448] fq_flush_timeout+0x55/0x160
[ 3.841368] ? fq_ring_free+0x1d0/0x1d0
[ 3.845200] ? fq_ring_free+0x1d0/0x1d0
[ 3.849034] call_timer_fn+0xbe/0x310
[ 3.852696] ? fq_ring_free+0x1d0/0x1d0
[ 3.856530] run_timer_softirq+0x223/0x6e0
[ 3.860625] ? sched_clock+0x5/0x10
[ 3.864108] ? sched_clock+0x5/0x10
[ 3.867594] __do_softirq+0x1b5/0x6f5
[ 3.871250] irq_exit+0xd4/0x130
[ 3.874470] smp_apic_timer_interrupt+0xb8/0x2f0
[ 3.879075] apic_timer_interrupt+0xf/0x20
[ 3.883159] </IRQ>
[ 3.885255] RIP: 0010:poll_idle+0x60/0xe7
[ 3.889252] RSP: 0018:ffffb1b201943e30 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
[ 3.896802] RAX: 0000000080200000 RBX: 000000000000008e RCX: 000000000000001f
[ 3.903918] RDX: 0000000000000000 RSI: 000000002819aa06 RDI: 0000000000000000
[ 3.911031] RBP: ffff9e93c6b33280 R08: 00000010f717d567 R09: 000000000010d205
[ 3.918146] R10: ffffb1b201943df8 R11: 0000000000000001 R12: 00000000e01b169d
[ 3.925260] R13: 0000000000000000 R14: ffffffffb12aa400 R15: 0000000000000000
[ 3.932382] cpuidle_enter_state+0xb4/0x470
[ 3.936558] do_idle+0x222/0x310
[ 3.939779] cpu_startup_entry+0x78/0x90
[ 3.943693] start_secondary+0x205/0x2e0
[ 3.947607] secondary_startup_64+0xa5/0xb0
[ 3.951783] ================================================================================
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
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