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| author | Simon Guo <wei.guo.simon@gmail.com> | 2018-05-23 09:02:02 +0200 |
|---|---|---|
| committer | Paul Mackerras <paulus@ozlabs.org> | 2018-06-01 02:30:14 +0200 |
| commit | 19c585eb45e360db43790c6724a3ea929ea03de3 (patch) | |
| tree | d307a2d9c7c05544fab12e812c33b4e62e2ff907 /arch | |
| parent | KVM: PPC: Book3S PR: Always fail transactions in guest privileged state (diff) | |
| download | linux-19c585eb45e360db43790c6724a3ea929ea03de3.tar.xz linux-19c585eb45e360db43790c6724a3ea929ea03de3.zip | |
KVM: PPC: Book3S PR: Restore NV regs after emulating mfspr from TM SPRs
Currently kvmppc_handle_fac() will not update NV GPRs and thus it can
return with GUEST_RESUME.
However PR KVM guest always disables MSR_TM bit in privileged state.
If PR privileged-state guest is trying to read TM SPRs, it will
trigger TM facility unavailable exception and fall into
kvmppc_handle_fac(). Then the emulation will be done by
kvmppc_core_emulate_mfspr_pr(). The mfspr instruction can include a
RT with NV reg. So it is necessary to restore NV GPRs at this case, to
reflect the update to NV RT.
This patch make kvmppc_handle_fac() return GUEST_RESUME_NV for TM
facility unavailable exceptions in guest privileged state.
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kvm/book3s_pr.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index cc26be87e3b8..bb9209947db9 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -989,6 +989,18 @@ static int kvmppc_handle_fac(struct kvm_vcpu *vcpu, ulong fac) break; } +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM + /* Since we disabled MSR_TM at privilege state, the mfspr instruction + * for TM spr can trigger TM fac unavailable. In this case, the + * emulation is handled by kvmppc_emulate_fac(), which invokes + * kvmppc_emulate_mfspr() finally. But note the mfspr can include + * RT for NV registers. So it need to restore those NV reg to reflect + * the update. + */ + if ((fac == FSCR_TM_LG) && !(kvmppc_get_msr(vcpu) & MSR_PR)) + return RESUME_GUEST_NV; +#endif + return RESUME_GUEST; } @@ -1350,8 +1362,7 @@ int kvmppc_handle_exit_pr(struct kvm_run *run, struct kvm_vcpu *vcpu, } #ifdef CONFIG_PPC_BOOK3S_64 case BOOK3S_INTERRUPT_FAC_UNAVAIL: - kvmppc_handle_fac(vcpu, vcpu->arch.shadow_fscr >> 56); - r = RESUME_GUEST; + r = kvmppc_handle_fac(vcpu, vcpu->arch.shadow_fscr >> 56); break; #endif case BOOK3S_INTERRUPT_MACHINE_CHECK: |