KVM: arm64: Store vcpu on the stack during __guest_enter()

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KVM uses tpidr_el2 as its private vcpu register, which makes sense for
non-vhe world switch as only KVM can access this register. This means
vhe Linux has to use tpidr_el1, which KVM has to save/restore as part
of the host context.

If the SDEI handler code runs behind KVMs back, it mustn't access any
per-cpu variables. To allow this on systems with vhe we need to make
the host use tpidr_el2, saving KVM from save/restoring it.

__guest_enter() stores the host_ctxt on the stack, do the same with
the vcpu.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

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James Morse 2018-01-08 15:38:03 +00:00 • committed by Catalin Marinas

parent 3423cab3e0

commit 32b03d1059

2 changed files with 10 additions and 6 deletions

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arch/arm64/kvm/hyp/entry.S

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arch/arm64/kvm/hyp/hyp-entry.S

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