| Message ID | 1377260760-32056-1-git-send-email-james.hogan@imgtec.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Aug 23, 2013 at 01:26:00PM +0100, James Hogan wrote: > When a KVM internal error occurs QEMU dumps the CPU state, however it > doesn't synchronise the state from KVM first so the dumped state is out > of date. Add the synchronisation calls before the dump in both locations > (which is used depends on whether the arch says to stop or not). > x86_cpu_dump_state() calls cpu_synchronize_state() already. > Note that x86 does a sync in its kvm_arch_stop_on_emulation_error() > function so at least for emulation errors is unaffected. > > Signed-off-by: James Hogan <james.hogan@imgtec.com> > Cc: Gleb Natapov <gleb@redhat.com> > Cc: Paolo Bonzini <pbonzini@redhat.com> > Cc: kvm@vger.kernel.org > --- > kvm-all.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/kvm-all.c b/kvm-all.c > index b788fcd..803141a 100644 > --- a/kvm-all.c > +++ b/kvm-all.c > @@ -1546,6 +1546,7 @@ static int kvm_handle_internal_error(CPUState *cpu, struct kvm_run *run) > if (run->internal.suberror == KVM_INTERNAL_ERROR_EMULATION) { > fprintf(stderr, "emulation failure\n"); > if (!kvm_arch_stop_on_emulation_error(cpu)) { > + kvm_cpu_synchronize_state(cpu); > cpu_dump_state(cpu, stderr, fprintf, CPU_DUMP_CODE); > return EXCP_INTERRUPT; > } > @@ -1701,6 +1702,7 @@ int kvm_cpu_exec(CPUState *cpu) > } while (ret == 0); > > if (ret < 0) { > + kvm_cpu_synchronize_state(cpu); > cpu_dump_state(cpu, stderr, fprintf, CPU_DUMP_CODE); > vm_stop(RUN_STATE_INTERNAL_ERROR); > } > -- > 1.8.1.2 > -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 23/08/13 13:58, Gleb Natapov wrote: > On Fri, Aug 23, 2013 at 01:26:00PM +0100, James Hogan wrote: >> When a KVM internal error occurs QEMU dumps the CPU state, however it >> doesn't synchronise the state from KVM first so the dumped state is out >> of date. Add the synchronisation calls before the dump in both locations >> (which is used depends on whether the arch says to stop or not). >> > x86_cpu_dump_state() calls cpu_synchronize_state() already. Ah yes, thanks. I hadn't noticed that. Out of the arches that support KVM only x86 and ppc call it. arm, mips (qemu support not upstream yet), and s390 don't. s390 never seems to emit that exit code, and arm only does so for unsupported exceptions (which should never happen). I'll fix in mips_cpu_dump_state() instead. Cheers James -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Aug 23, 2013 at 02:41:13PM +0100, James Hogan wrote: > On 23/08/13 13:58, Gleb Natapov wrote: > > On Fri, Aug 23, 2013 at 01:26:00PM +0100, James Hogan wrote: > >> When a KVM internal error occurs QEMU dumps the CPU state, however it > >> doesn't synchronise the state from KVM first so the dumped state is out > >> of date. Add the synchronisation calls before the dump in both locations > >> (which is used depends on whether the arch says to stop or not). > >> > > x86_cpu_dump_state() calls cpu_synchronize_state() already. > > Ah yes, thanks. I hadn't noticed that. > > Out of the arches that support KVM only x86 and ppc call it. arm, mips > (qemu support not upstream yet), and s390 don't. s390 never seems to > emit that exit code, and arm only does so for unsupported exceptions > (which should never happen). > > I'll fix in mips_cpu_dump_state() instead. > Moving cpu_synchronize_state() up to cpu_dump_state() would be better. -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Am 24.08.2013 12:37, schrieb Gleb Natapov: > On Fri, Aug 23, 2013 at 02:41:13PM +0100, James Hogan wrote: >> On 23/08/13 13:58, Gleb Natapov wrote: >>> On Fri, Aug 23, 2013 at 01:26:00PM +0100, James Hogan wrote: >>>> When a KVM internal error occurs QEMU dumps the CPU state, however it >>>> doesn't synchronise the state from KVM first so the dumped state is out >>>> of date. Add the synchronisation calls before the dump in both locations >>>> (which is used depends on whether the arch says to stop or not). >>>> >>> x86_cpu_dump_state() calls cpu_synchronize_state() already. >> >> Ah yes, thanks. I hadn't noticed that. >> >> Out of the arches that support KVM only x86 and ppc call it. arm, mips >> (qemu support not upstream yet), and s390 don't. s390 never seems to >> emit that exit code, and arm only does so for unsupported exceptions >> (which should never happen). >> >> I'll fix in mips_cpu_dump_state() instead. >> > Moving cpu_synchronize_state() up to cpu_dump_state() would be better. Yes, please. I did not review the hooks themselves much, just avoided global functions. Andreas
diff --git a/kvm-all.c b/kvm-all.c index b788fcd..803141a 100644 --- a/kvm-all.c +++ b/kvm-all.c @@ -1546,6 +1546,7 @@ static int kvm_handle_internal_error(CPUState *cpu, struct kvm_run *run) if (run->internal.suberror == KVM_INTERNAL_ERROR_EMULATION) { fprintf(stderr, "emulation failure\n"); if (!kvm_arch_stop_on_emulation_error(cpu)) { + kvm_cpu_synchronize_state(cpu); cpu_dump_state(cpu, stderr, fprintf, CPU_DUMP_CODE); return EXCP_INTERRUPT; } @@ -1701,6 +1702,7 @@ int kvm_cpu_exec(CPUState *cpu) } while (ret == 0); if (ret < 0) { + kvm_cpu_synchronize_state(cpu); cpu_dump_state(cpu, stderr, fprintf, CPU_DUMP_CODE); vm_stop(RUN_STATE_INTERNAL_ERROR); }
When a KVM internal error occurs QEMU dumps the CPU state, however it doesn't synchronise the state from KVM first so the dumped state is out of date. Add the synchronisation calls before the dump in both locations (which is used depends on whether the arch says to stop or not). Note that x86 does a sync in its kvm_arch_stop_on_emulation_error() function so at least for emulation errors is unaffected. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: kvm@vger.kernel.org --- kvm-all.c | 2 ++ 1 file changed, 2 insertions(+)