Messages in this thread | | | Date | Sat, 30 Mar 2019 09:56:14 +0000 | From | Marc Zyngier <> | Subject | Re: [PATCH 1/1] KVM: arm/arm64: arch_timer: Fix TimerValue TVAL calculation in KVM |
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On Fri, 29 Mar 2019 20:12:53 +0000, Wei Huang <wei@redhat.com> wrote: > > Recently the generic timer test of kvm-unit-tests failed to complete > (stalled) when a physical timer is being used. This issue is caused > by incorrect update of CNT_CVAL when TimerValue is being accessed, > introduced by 'Commit 84135d3d18da ("KVM: arm/arm64: consolidate arch > timer trap handlers")'. According to Arm ARM, the read/write behavior > of accesses to TimeValue registers is expected to be: > > * READ: TimerValue = (CompareValue – (Counter - Offset) > * WRITE: CompareValue = ((Counter - Offset) + Sign(TimerValue) > > This patch fixes the TVAL read/write code path according to the > specification. > > Signed-off-by: Wei Huang <wei@redhat.com>
Huh... Nice catch. I guess I only ran this with a VHE host, where this code path is unused.
Thanks,
M.
-- Jazz is not dead, it just smell funny.
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