| Message ID | b394ef2e743ebd57d3b8fb5ce1d5069c030ffcfc.1598382343.git.thomas.lendacky@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | SEV-ES guest support | expand |
On 8/25/20 2:05 PM, Tom Lendacky wrote: > From: Tom Lendacky <thomas.lendacky@amd.com> > > An SEV-ES guest does not allow register state to be altered once it has > been measured. When a SEV-ES guest issues a reboot command, Qemu will > reset the vCPU state and resume the guest. This will cause failures under > SEV-ES, so prevent that from occurring. > > Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> > --- > accel/kvm/kvm-all.c | 8 ++++++++ > include/sysemu/cpus.h | 2 ++ > include/sysemu/hw_accel.h | 4 ++++ > include/sysemu/kvm.h | 2 ++ > softmmu/cpus.c | 5 +++++ > softmmu/vl.c | 5 ++++- > 6 files changed, 25 insertions(+), 1 deletion(-) > > diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c > index 54e8fd098d..1d925821b2 100644 > --- a/accel/kvm/kvm-all.c > +++ b/accel/kvm/kvm-all.c > @@ -2384,6 +2384,14 @@ void kvm_flush_coalesced_mmio_buffer(void) > s->coalesced_flush_in_progress = false; > } > > +bool kvm_cpu_check_resettable(void) > +{ > + /* If we have a valid reset vector override, then SEV-ES is active > + * and the CPU can't be reset. > + */ > + return !kvm_state->reset_valid; > +} > + > static void do_kvm_cpu_synchronize_state(CPUState *cpu, run_on_cpu_data arg) > { > if (!cpu->vcpu_dirty) { > diff --git a/include/sysemu/cpus.h b/include/sysemu/cpus.h > index 3c1da6a018..6d688c757f 100644 > --- a/include/sysemu/cpus.h > +++ b/include/sysemu/cpus.h > @@ -24,6 +24,8 @@ void dump_drift_info(void); > void qemu_cpu_kick_self(void); > void qemu_timer_notify_cb(void *opaque, QEMUClockType type); > > +bool cpu_is_resettable(void); > + > void cpu_synchronize_all_states(void); > void cpu_synchronize_all_post_reset(void); > void cpu_synchronize_all_post_init(void); > diff --git a/include/sysemu/hw_accel.h b/include/sysemu/hw_accel.h > index e128f8b06b..1fddf4f5e1 100644 > --- a/include/sysemu/hw_accel.h > +++ b/include/sysemu/hw_accel.h > @@ -17,6 +17,10 @@ > #include "sysemu/hvf.h" > #include "sysemu/whpx.h" > > +static inline bool cpu_check_resettable(void) > +{ > + return kvm_enabled() ? kvm_cpu_check_resettable() : true; > +} There's a missing newline here that would separate the closing brace from the function below this one. > static inline void cpu_synchronize_state(CPUState *cpu) > { > if (kvm_enabled()) { > diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h > index f74cfa85ab..eb94bbbff9 100644 > --- a/include/sysemu/kvm.h > +++ b/include/sysemu/kvm.h > @@ -494,6 +494,8 @@ int kvm_physical_memory_addr_from_host(KVMState *s, void *ram_addr, > > #endif /* NEED_CPU_H */ > > +bool kvm_cpu_check_resettable(void); > + > void kvm_cpu_synchronize_state(CPUState *cpu); > void kvm_cpu_synchronize_post_reset(CPUState *cpu); > void kvm_cpu_synchronize_post_init(CPUState *cpu); > diff --git a/softmmu/cpus.c b/softmmu/cpus.c > index a802e899ab..32f286643f 100644 > --- a/softmmu/cpus.c > +++ b/softmmu/cpus.c > @@ -927,6 +927,11 @@ void hw_error(const char *fmt, ...) > abort(); > } > > +bool cpu_is_resettable(void) > +{ > + return cpu_check_resettable(); > +} > + > void cpu_synchronize_all_states(void) > { > CPUState *cpu; > diff --git a/softmmu/vl.c b/softmmu/vl.c > index 4eb9d1f7fd..422fbb1650 100644 > --- a/softmmu/vl.c > +++ b/softmmu/vl.c > @@ -1475,7 +1475,10 @@ void qemu_system_guest_crashloaded(GuestPanicInformation *info) > > void qemu_system_reset_request(ShutdownCause reason) > { > - if (no_reboot && reason != SHUTDOWN_CAUSE_SUBSYSTEM_RESET) { > + if (!cpu_is_resettable()) { > + error_report("cpus are not resettable, terminating"); > + shutdown_requested = reason; > + } else if (no_reboot && reason != SHUTDOWN_CAUSE_SUBSYSTEM_RESET) { > shutdown_requested = reason; > } else { > reset_requested = reason; >
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 54e8fd098d..1d925821b2 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -2384,6 +2384,14 @@ void kvm_flush_coalesced_mmio_buffer(void) s->coalesced_flush_in_progress = false; } +bool kvm_cpu_check_resettable(void) +{ + /* If we have a valid reset vector override, then SEV-ES is active + * and the CPU can't be reset. + */ + return !kvm_state->reset_valid; +} + static void do_kvm_cpu_synchronize_state(CPUState *cpu, run_on_cpu_data arg) { if (!cpu->vcpu_dirty) { diff --git a/include/sysemu/cpus.h b/include/sysemu/cpus.h index 3c1da6a018..6d688c757f 100644 --- a/include/sysemu/cpus.h +++ b/include/sysemu/cpus.h @@ -24,6 +24,8 @@ void dump_drift_info(void); void qemu_cpu_kick_self(void); void qemu_timer_notify_cb(void *opaque, QEMUClockType type); +bool cpu_is_resettable(void); + void cpu_synchronize_all_states(void); void cpu_synchronize_all_post_reset(void); void cpu_synchronize_all_post_init(void); diff --git a/include/sysemu/hw_accel.h b/include/sysemu/hw_accel.h index e128f8b06b..1fddf4f5e1 100644 --- a/include/sysemu/hw_accel.h +++ b/include/sysemu/hw_accel.h @@ -17,6 +17,10 @@ #include "sysemu/hvf.h" #include "sysemu/whpx.h" +static inline bool cpu_check_resettable(void) +{ + return kvm_enabled() ? kvm_cpu_check_resettable() : true; +} static inline void cpu_synchronize_state(CPUState *cpu) { if (kvm_enabled()) { diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h index f74cfa85ab..eb94bbbff9 100644 --- a/include/sysemu/kvm.h +++ b/include/sysemu/kvm.h @@ -494,6 +494,8 @@ int kvm_physical_memory_addr_from_host(KVMState *s, void *ram_addr, #endif /* NEED_CPU_H */ +bool kvm_cpu_check_resettable(void); + void kvm_cpu_synchronize_state(CPUState *cpu); void kvm_cpu_synchronize_post_reset(CPUState *cpu); void kvm_cpu_synchronize_post_init(CPUState *cpu); diff --git a/softmmu/cpus.c b/softmmu/cpus.c index a802e899ab..32f286643f 100644 --- a/softmmu/cpus.c +++ b/softmmu/cpus.c @@ -927,6 +927,11 @@ void hw_error(const char *fmt, ...) abort(); } +bool cpu_is_resettable(void) +{ + return cpu_check_resettable(); +} + void cpu_synchronize_all_states(void) { CPUState *cpu; diff --git a/softmmu/vl.c b/softmmu/vl.c index 4eb9d1f7fd..422fbb1650 100644 --- a/softmmu/vl.c +++ b/softmmu/vl.c @@ -1475,7 +1475,10 @@ void qemu_system_guest_crashloaded(GuestPanicInformation *info) void qemu_system_reset_request(ShutdownCause reason) { - if (no_reboot && reason != SHUTDOWN_CAUSE_SUBSYSTEM_RESET) { + if (!cpu_is_resettable()) { + error_report("cpus are not resettable, terminating"); + shutdown_requested = reason; + } else if (no_reboot && reason != SHUTDOWN_CAUSE_SUBSYSTEM_RESET) { shutdown_requested = reason; } else { reset_requested = reason;