AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity

kvm: x86: limit the maximum number of vPMU fixed counters to 3

Browse Source 
Some new Intel platforms (such as TGL) already have the
fourth fixed counter TOPDOWN.SLOTS, but it has not been
fully enabled on KVM and the host.

Therefore, we limit edx.split.num_counters_fixed to 3,
so that it does not break the kvm-unit-tests PMU test
case and bad-handled userspace.

Signed-off-by: Like Xu <like.xu@linux.intel.com>
Message-Id: <20200624015928.118614-1-like.xu@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Like Xu 2020-06-24 09:59:28 +08:00 committed by Paolo Bonzini
parent 761e416934
commit 2e8cd7a3b8
2 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/kvm/cpuid.c
View File

@ -606,7 +606,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
eax.split.bit_width = cap.bit_width_gp;
eax.split.mask_length = cap.events_mask_len;
edx.split.num_counters_fixed = cap.num_counters_fixed;
edx.split.num_counters_fixed = min(cap.num_counters_fixed, MAX_FIXED_COUNTERS);
edx.split.bit_width_fixed = cap.bit_width_fixed;
edx.split.reserved = 0;

2
arch/x86/kvm/pmu.h
View File

@ -15,6 +15,8 @@
#define VMWARE_BACKDOOR_PMC_REAL_TIME 0x10001
#define VMWARE_BACKDOOR_PMC_APPARENT_TIME 0x10002
#define MAX_FIXED_COUNTERS 3
struct kvm_event_hw_type_mapping {
u8 eventsel;
u8 unit_mask;