[PATCH 4/7 v3] KVM: PPC: BOOKE: Clear guest dbsr in userspace exit KVM_EXIT_DEBUG
Dbsr is not visible to userspace and we do not think any need to expose this to userspace because: Userspace cannot inject debug interrupt to guest (as this does not know guest ability to handle debug interrupt), so userspace will always clear DBSR. Now if userspace has to always clear DBSR in KVM_EXIT_DEBUG handling then clearing dbsr in kernel looks simple as this avoid doing SET_SREGS/set_one_reg() to clear DBSR Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- v2-v3 - Small comment in code, patch description have sufficient detail arch/powerpc/kvm/booke.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index 322da7d..b4ab86c 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -735,6 +735,8 @@ static int kvmppc_handle_debug(struct kvm_run *run, struct kvm_vcpu *vcpu) struct debug_reg *dbg_reg = (vcpu-arch.shadow_dbg_reg); u32 dbsr = vcpu-arch.dbsr; + /* Clear guest dbsr (vcpu-arch.dbsr) */ + vcpu-arch.dbsr = 0; run-debug.arch.status = 0; run-debug.arch.address = vcpu-arch.pc; -- 1.9.3 -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH 4/7 v3] KVM: PPC: BOOKE: Clear guest dbsr in userspace exit KVM_EXIT_DEBUG
Dbsr is not visible to userspace and we do not think any need to expose this to userspace because: Userspace cannot inject debug interrupt to guest (as this does not know guest ability to handle debug interrupt), so userspace will always clear DBSR. Now if userspace has to always clear DBSR in KVM_EXIT_DEBUG handling then clearing dbsr in kernel looks simple as this avoid doing SET_SREGS/set_one_reg() to clear DBSR Signed-off-by: Bharat Bhushan bharat.bhus...@freescale.com --- v2-v3 - Small comment in code, patch description have sufficient detail arch/powerpc/kvm/booke.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index 322da7d..b4ab86c 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -735,6 +735,8 @@ static int kvmppc_handle_debug(struct kvm_run *run, struct kvm_vcpu *vcpu) struct debug_reg *dbg_reg = (vcpu-arch.shadow_dbg_reg); u32 dbsr = vcpu-arch.dbsr; + /* Clear guest dbsr (vcpu-arch.dbsr) */ + vcpu-arch.dbsr = 0; run-debug.arch.status = 0; run-debug.arch.address = vcpu-arch.pc; -- 1.9.3 -- To unsubscribe from this list: send the line unsubscribe kvm-ppc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
