From: Nicholas Piggin npiggin@gmail.com
[ Upstream commit 4782e0cd0d184d727ad3b0cfe20d1d44d9f98239 ]
The softpatch interrupt sets HSRR0 to the faulting instruction +4, so it should subtract 4 for the faulting instruction address in the case it is a TM softpatch interrupt (the instruction was not executed) and it was not emulated.
Signed-off-by: Nicholas Piggin npiggin@gmail.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/20210811160134.904987-4-npiggin@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/kvm/book3s_hv_tm.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_hv_tm.c b/arch/powerpc/kvm/book3s_hv_tm.c index e7fd60cf9780..327abfbe13c3 100644 --- a/arch/powerpc/kvm/book3s_hv_tm.c +++ b/arch/powerpc/kvm/book3s_hv_tm.c @@ -49,6 +49,15 @@ int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu) u64 newmsr, bescr; int ra, rs;
+ /* + * The TM softpatch interrupt sets NIP to the instruction following + * the faulting instruction, which is not executed. Rewind nip to the + * faulting instruction so it looks like a normal synchronous + * interrupt, then update nip in the places where the instruction is + * emulated. + */ + vcpu->arch.regs.nip -= 4; + /* * rfid, rfebb, and mtmsrd encode bit 31 = 0 since it's a reserved bit * in these instructions, so masking bit 31 out doesn't change these @@ -70,7 +79,7 @@ int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu) (newmsr & MSR_TM))); newmsr = sanitize_msr(newmsr); vcpu->arch.shregs.msr = newmsr; - vcpu->arch.cfar = vcpu->arch.regs.nip - 4; + vcpu->arch.cfar = vcpu->arch.regs.nip; vcpu->arch.regs.nip = vcpu->arch.shregs.srr0; return RESUME_GUEST;
@@ -103,7 +112,7 @@ int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu) vcpu->arch.bescr = bescr; msr = (msr & ~MSR_TS_MASK) | MSR_TS_T; vcpu->arch.shregs.msr = msr; - vcpu->arch.cfar = vcpu->arch.regs.nip - 4; + vcpu->arch.cfar = vcpu->arch.regs.nip; vcpu->arch.regs.nip = vcpu->arch.ebbrr; return RESUME_GUEST;
@@ -119,6 +128,7 @@ int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu) newmsr = (newmsr & ~MSR_LE) | (msr & MSR_LE); newmsr = sanitize_msr(newmsr); vcpu->arch.shregs.msr = newmsr; + vcpu->arch.regs.nip += 4; return RESUME_GUEST;
/* ignore bit 31, see comment above */ @@ -155,6 +165,7 @@ int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu) msr = (msr & ~MSR_TS_MASK) | MSR_TS_S; } vcpu->arch.shregs.msr = msr; + vcpu->arch.regs.nip += 4; return RESUME_GUEST;
/* ignore bit 31, see comment above */ @@ -192,6 +203,7 @@ int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu) vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) | (((msr & MSR_TS_MASK) >> MSR_TS_S_LG) << 29); vcpu->arch.shregs.msr &= ~MSR_TS_MASK; + vcpu->arch.regs.nip += 4; return RESUME_GUEST;
/* ignore bit 31, see comment above */ @@ -223,6 +235,7 @@ int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu) vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) | (((msr & MSR_TS_MASK) >> MSR_TS_S_LG) << 29); vcpu->arch.shregs.msr = msr | MSR_TS_S; + vcpu->arch.regs.nip += 4; return RESUME_GUEST; }