iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

KVM: selftests: Avoid infinite loop in hyperv_features when invtsc is missing

Browse Source 
When X86_FEATURE_INVTSC is missing, guest_test_msrs_access() was supposed
to skip testing dependent Hyper-V invariant TSC feature. Unfortunately,
'continue' does not lead to that as stage is not incremented. Moreover,
'vm' allocated with vm_create_with_one_vcpu() is not freed and the test
runs out of available file descriptors very quickly.

Fixes: bd827bd77537 ("KVM: selftests: Test Hyper-V invariant TSC control")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20240129085847.2674082-1-vkuznets@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
This commit is contained in:
Vitaly Kuznetsov 2024-01-29 09:58:46 +01:00 committed by Sean Christopherson
parent 46fee9e389
commit 8ad4855273
1 changed files with 5 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
tools/testing/selftests/kvm/x86_64/hyperv_features.c
View File

@ -454,7 +454,7 @@ static void guest_test_msrs_access(void)
case 44:
/* MSR is not available when CPUID feature bit is unset */
if (!has_invtsc)
continue;
goto next_stage;
msr->idx = HV_X64_MSR_TSC_INVARIANT_CONTROL;
msr->write = false;
msr->fault_expected = true;
@ -462,7 +462,7 @@ static void guest_test_msrs_access(void)
case 45:
/* MSR is vailable when CPUID feature bit is set */
if (!has_invtsc)
continue;
goto next_stage;
vcpu_set_cpuid_feature(vcpu, HV_ACCESS_TSC_INVARIANT);
msr->idx = HV_X64_MSR_TSC_INVARIANT_CONTROL;
msr->write = false;
@ -471,7 +471,7 @@ static void guest_test_msrs_access(void)
case 46:
/* Writing bits other than 0 is forbidden */
if (!has_invtsc)
continue;
goto next_stage;
msr->idx = HV_X64_MSR_TSC_INVARIANT_CONTROL;
msr->write = true;
msr->write_val = 0xdeadbeef;
@ -480,7 +480,7 @@ static void guest_test_msrs_access(void)
case 47:
/* Setting bit 0 enables the feature */
if (!has_invtsc)
continue;
goto next_stage;
msr->idx = HV_X64_MSR_TSC_INVARIANT_CONTROL;
msr->write = true;
msr->write_val = 1;
@ -513,6 +513,7 @@ static void guest_test_msrs_access(void)
return;
}
next_stage:
stage++;
kvm_vm_free(vm);
}