diff options
| author | Eduardo Habkost <ehabkost@redhat.com> | 2017-03-09 15:12:11 -0300 |
|---|---|---|
| committer | Eduardo Habkost <ehabkost@redhat.com> | 2017-03-10 15:01:08 -0300 |
| commit | 40e80ee4113ad957b633cbdddb7423952bb76974 (patch) | |
| tree | 54df8544831856ced94977110910f38849288a0d /target/i386 | |
| parent | 20271d484069f154fb262507e63adc3a37e885d2 (diff) | |
i386/kvm: Blacklist TSX on known broken hosts
Some Intel CPUs are known to have a broken TSX implementation. A
microcode update from Intel disabled TSX on those CPUs, but
GET_SUPPORTED_CPUID might be reporting it as supported if the
hosts were not updated yet.
Manually fixup the GET_SUPPORTED_CPUID data to ensure we will
never enable TSX when running on those hosts.
Reference:
* glibc commit 2702856bf45c82cf8e69f2064f5aa15c0ceb6359:
https://sourceware.org/git/?p=glibc.git;a=commit;h=2702856bf45c82cf8e69f2064f5aa15c0ceb6359
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20170309181212.18864-3-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Diffstat (limited to 'target/i386')
| -rw-r--r-- | target/i386/kvm.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/target/i386/kvm.c b/target/i386/kvm.c index 887a81268f..472399fb2c 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -266,6 +266,19 @@ static int get_para_features(KVMState *s) return features; } +static bool host_tsx_blacklisted(void) +{ + int family, model, stepping;\ + char vendor[CPUID_VENDOR_SZ + 1]; + + host_vendor_fms(vendor, &family, &model, &stepping); + + /* Check if we are running on a Haswell host known to have broken TSX */ + return !strcmp(vendor, CPUID_VENDOR_INTEL) && + (family == 6) && + ((model == 63 && stepping < 4) || + model == 60 || model == 69 || model == 70); +} /* Returns the value for a specific register on the cpuid entry */ @@ -349,6 +362,10 @@ uint32_t kvm_arch_get_supported_cpuid(KVMState *s, uint32_t function, } } else if (function == 6 && reg == R_EAX) { ret |= CPUID_6_EAX_ARAT; /* safe to allow because of emulated APIC */ + } else if (function == 7 && index == 0 && reg == R_EBX) { + if (host_tsx_blacklisted()) { + ret &= ~(CPUID_7_0_EBX_RTM | CPUID_7_0_EBX_HLE); + } } else if (function == 0x80000001 && reg == R_EDX) { /* On Intel, kvm returns cpuid according to the Intel spec, * so add missing bits according to the AMD spec: |