diff options
| author | Nicholas Piggin <npiggin@gmail.com> | 2020-11-28 17:07:24 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-12-04 01:01:23 +1100 |
| commit | 1d15ffdfc94127d75e04a88344ee1ce8c79f05fd (patch) | |
| tree | c1adecfeec8a864532decd171e4dba15112c18df /arch/powerpc/kvm | |
| parent | 067c9f9c98c8804b07751994c51d8557e440821e (diff) | |
KVM: PPC: Book3S HV: Ratelimit machine check messages coming from guests
A number of machine check exceptions are triggerable by the guest.
Ratelimit these to avoid a guest flooding the host console and logs.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Use dedicated ratelimit state, not printk_ratelimit()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201128070728.825934-5-npiggin@gmail.com
Diffstat (limited to 'arch/powerpc/kvm')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 0faafe6f8c4e..cfaa91b27112 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -1327,9 +1327,15 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu, case BOOK3S_INTERRUPT_SYSTEM_RESET: r = RESUME_GUEST; break; - case BOOK3S_INTERRUPT_MACHINE_CHECK: - /* Print the MCE event to host console. */ - machine_check_print_event_info(&vcpu->arch.mce_evt, false, true); + case BOOK3S_INTERRUPT_MACHINE_CHECK: { + static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL, + DEFAULT_RATELIMIT_BURST); + /* + * Print the MCE event to host console. Ratelimit so the guest + * can't flood the host log. + */ + if (__ratelimit(&rs)) + machine_check_print_event_info(&vcpu->arch.mce_evt,false, true); /* * If the guest can do FWNMI, exit to userspace so it can @@ -1357,6 +1363,7 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu, r = RESUME_HOST; break; + } case BOOK3S_INTERRUPT_PROGRAM: { ulong flags; @@ -1516,11 +1523,16 @@ static int kvmppc_handle_nested_exit(struct kvm_vcpu *vcpu) r = RESUME_GUEST; break; case BOOK3S_INTERRUPT_MACHINE_CHECK: + { + static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL, + DEFAULT_RATELIMIT_BURST); /* Pass the machine check to the L1 guest */ r = RESUME_HOST; /* Print the MCE event to host console. */ - machine_check_print_event_info(&vcpu->arch.mce_evt, false, true); + if (__ratelimit(&rs)) + machine_check_print_event_info(&vcpu->arch.mce_evt, false, true); break; + } /* * We get these next two if the guest accesses a page which it thinks * it has mapped but which is not actually present, either because |