Mark Rutland da5a3ce66b KVM: arm64: Fix caching of host MDCR_EL2 value ... At boot time, KVM stashes the host MDCR_EL2 value, but only does this when the kernel is not running in hyp mode (i.e. is non-VHE). In these cases, the stashed value of MDCR_EL2.HPMN happens to be zero, which can lead to CONSTRAINED UNPREDICTABLE behaviour. Since we use this value to derive the MDCR_EL2 value when switching to/from a guest, after a guest have been run, the performance counters do not behave as expected. This has been observed to result in accesses via PMXEVTYPER_EL0 and PMXEVCNTR_EL0 not affecting the relevant counters, resulting in events not being counted. In these cases, only the fixed-purpose cycle counter appears to work as expected. Fix this by always stashing the host MDCR_EL2 value, regardless of VHE. Cc: Christopher Dall <christoffer.dall@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: stable@vger.kernel.org Fixes: 1e947bad0b ("arm64: KVM: Skip HYP setup when already running in HYP") Tested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>		2018-10-17 18:32:46 +01:00
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kvm	KVM: arm64: Fix caching of host MDCR_EL2 value	2018-10-17 18:32:46 +01:00
lib	KVM: eventfd: fix NULL deref irqbypass consumer	2017-01-12 14:42:34 +01:00
Makefile	virt: Add virt directory to the top Makefile	2015-10-01 15:06:44 +02:00