linux

iv/linux

History

James Morse 11b41626bd KVM: arm64: Skip more of the SError vaxorcism

During __guest_exit() we need to consume any SError left pending by the
guest so it doesn't contaminate the host. With v8.2 we use the
ESB-instruction. For systems without v8.2, we use dsb+isb and unmask
SError. We do this on every guest exit.

Use the same dsb+isr_el1 trick, this lets us know if an SError is pending
after the dsb, allowing us to skip the isb and self-synchronising PSTATE
write if its not.

This means SError remains masked during KVM's world-switch, so any SError
that occurs during this time is reported by the host, instead of causing
a hyp-panic.

As we're benchmarking this code lets polish the layout. If you give gcc
likely()/unlikely() hints in an if() condition, it shuffles the generated
assembly so that the likely case is immediately after the branch. Lets
do the same here.

Signed-off-by: James Morse <james.morse@arm.com>

Changes since v2:
 * Added isb after the dsb to prevent an early read

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

2019-07-05 13:03:34 +01:00

hyp

KVM: arm64: Skip more of the SError vaxorcism

2019-07-05 13:03:34 +01:00

debug.c

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234

2019-06-19 17:09:07 +02:00

fpsimd.c

KVM: arm64/sve: Context switch the SVE registers

2019-03-29 14:41:53 +00:00

guest.c

SPDX update for 5.2-rc6