linux/virt/kvm/arm
Mark Rutland 1cfbb484de KVM: arm/arm64: Correct AArch32 SPSR on exception entry
Confusingly, there are three SPSR layouts that a kernel may need to deal
with:

(1) An AArch64 SPSR_ELx view of an AArch64 pstate
(2) An AArch64 SPSR_ELx view of an AArch32 pstate
(3) An AArch32 SPSR_* view of an AArch32 pstate

When the KVM AArch32 support code deals with SPSR_{EL2,HYP}, it's either
dealing with #2 or #3 consistently. On arm64 the PSR_AA32_* definitions
match the AArch64 SPSR_ELx view, and on arm the PSR_AA32_* definitions
match the AArch32 SPSR_* view.

However, when we inject an exception into an AArch32 guest, we have to
synthesize the AArch32 SPSR_* that the guest will see. Thus, an AArch64
host needs to synthesize layout #3 from layout #2.

This patch adds a new host_spsr_to_spsr32() helper for this, and makes
use of it in the KVM AArch32 support code. For arm64 we need to shuffle
the DIT bit around, and remove the SS bit, while for arm we can use the
value as-is.

I've open-coded the bit manipulation for now to avoid having to rework
the existing PSR_* definitions into PSR64_AA32_* and PSR32_AA32_*
definitions. I hope to perform a more thorough refactoring in future so
that we can handle pstate view manipulation more consistently across the
kernel tree.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200108134324.46500-4-mark.rutland@arm.com
2020-01-19 18:06:14 +00:00
..
hyp KVM: arm: vgic-v3: Mark expected switch fall-through 2019-07-26 15:37:11 +01:00
vgic KVM: arm/arm64: vgic: Handle GICR_PENDBASER.PTZ filed as RAZ 2020-01-19 16:05:11 +00:00
aarch32.c KVM: arm/arm64: Correct AArch32 SPSR on exception entry 2020-01-19 18:06:14 +00:00
arch_timer.c KVM: arm/arm64: Let the timer expire in hardirq context on RT 2019-11-07 16:13:33 +00:00
arm.c KVM: arm: Remove duplicate include 2020-01-19 18:03:33 +00:00
hypercalls.c KVM: arm64: Support stolen time reporting via shared structure 2019-10-21 19:20:28 +01:00
mmio.c KVM: arm64: Only sign-extend MMIO up to register width 2020-01-19 16:05:10 +00:00
mmu.c KVM: arm/arm64: Re-check VMA on detecting a poisoned page 2020-01-19 18:05:20 +00:00
perf.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
pmu.c KVM: arm64: pmu: Reset sample period on overflow handling 2019-10-20 10:47:07 +01:00
psci.c KVM: arm/arm64: Factor out hypercall handling from PSCI code 2019-10-21 19:20:26 +01:00
pvtime.c KVM: arm64: Provide VCPU attributes for stolen time 2019-10-21 19:20:29 +01:00
trace.h KVM: arm/arm64: Fix TRACE_INCLUDE_PATH 2019-02-19 21:05:51 +00:00