4.9-stable review patch. If anyone has any objections, please let me know.
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From: James Morse james.morse@arm.com
[ Upstream commit e8ec032b182cd4841605de4fc297a8edffe55972 ]
When KVM panics, it hurridly restores the host context and parachutes into the host's panic() code. At some point panic() touches the physical timer/counter. Unless we are an arm64 system with VHE, this traps back to EL2. If we're lucky, we panic again.
Add a __timer_save_state() call to KVMs hyp_panic() path, this saves the guest registers and disables the traps for the host.
Fixes: 53fd5b6487e4 ("arm64: KVM: Add panic handling") Signed-off-by: James Morse james.morse@arm.com Reviewed-by: Marc Zyngier marc.zyngier@arm.com Reviewed-by: Christoffer Dall cdall@linaro.org Signed-off-by: Christoffer Dall cdall@linaro.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm64/kvm/hyp/switch.c | 1 + 1 file changed, 1 insertion(+)
--- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -404,6 +404,7 @@ void __hyp_text __noreturn __hyp_panic(v
vcpu = (struct kvm_vcpu *)read_sysreg(tpidr_el2); host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context); + __timer_save_state(vcpu); __deactivate_traps(vcpu); __deactivate_vm(vcpu); __sysreg_restore_host_state(host_ctxt);