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Commit a2723ce7 authored by Alexander Graf's avatar Alexander Graf Committed by Avi Kivity
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KVM: PPC: e500mc: Move r1/r2 restoration very early 



If we hit any exception whatsoever in the restore path and r1/r2 aren't the
host registers, we don't get a working oops. So it's always a good idea to
restore them as early as possible.

This time, it actually has practical reasons to do so too, since we need to
have the host page fault handler fix up our guest instruction read code. And
for that to work we need r1/r2 restored.

Signed-off-by: default avatarAlexander Graf <agraf@suse.de>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 79300f8c

arch/powerpc/kvm/bookehv_interrupts.S

+6 −6
Original line number Diff line number Diff line
@@ -67,6 +67,12 @@ 
 * saved in vcpu: cr, ctr, r3-r13

 */

.macro kvm_handler_common intno, srr0, flags

	/* Restore host stack pointer */

	PPC_STL	r1, VCPU_GPR(r1)(r4)

	PPC_STL	r2, VCPU_GPR(r2)(r4)

	PPC_LL	r1, VCPU_HOST_STACK(r4)

	PPC_LL	r2, HOST_R2(r1)



	mfspr	r10, SPRN_PID

	lwz	r8, VCPU_HOST_PID(r4)

	PPC_LL	r11, VCPU_SHARED(r4)
@@ -290,10 +296,8 @@ _GLOBAL(kvmppc_resume_host) 
	/* Save remaining volatile guest register state to vcpu. */

	mfspr	r3, SPRN_VRSAVE

	PPC_STL	r0, VCPU_GPR(r0)(r4)

	PPC_STL	r1, VCPU_GPR(r1)(r4)

	mflr	r5

	mfspr	r6, SPRN_SPRG4

	PPC_STL	r2, VCPU_GPR(r2)(r4)

	PPC_STL	r5, VCPU_LR(r4)

	mfspr	r7, SPRN_SPRG5

	PPC_STL	r3, VCPU_VRSAVE(r4)
@@ -334,10 +338,6 @@ _GLOBAL(kvmppc_resume_host) 
	mtspr	SPRN_EPCR, r3

	isync



	/* Restore host stack pointer */

	PPC_LL	r1, VCPU_HOST_STACK(r4)

	PPC_LL	r2, HOST_R2(r1)



	/* Switch to kernel stack and jump to handler. */

	PPC_LL	r3, HOST_RUN(r1)

	mr	r5, r14 /* intno */