shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-03-25 12:00:22 +09:00
Code Issues Packages Projects Releases Wiki Activity

ANDROID: KVM: arm64: pkvm: Don't access kvm_arm_hyp_percpu_base at EL1

Browse Source 
The host KVM PMU code can currently index kvm_arm_hyp_percpu_base[]
through this_cpu_ptr_hyp_sym(), but will not actually dereference that
pointer when protected KVM is enabled. In preparation for making
kvm_arm_hyp_percpu_base[] unaccessible to the host, let's make sure the
indexing in hyp per-cpu pages is also done after the static key check to
avoid spurious accesses to EL2-private data from EL1.

Signed-off-by: Quentin Perret <qperret@google.com>
Bug: 225169428
Change-Id: I3f4e3f7ee789c31a1ae1f67e07edf8fb34f520b9
This commit is contained in:
Quentin Perret
2022-03-30 16:11:28 +01:00
parent b576a36a95
commit ae49ca9a17
1 changed files with 12 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

16
arch/arm64/kvm/pmu.c
View File

@@ -31,9 +31,13 @@ static bool kvm_pmu_switch_needed(struct perf_event_attr *attr)
*/
void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr)
{
struct kvm_host_data *ctx = this_cpu_ptr_hyp_sym(kvm_host_data);
struct kvm_host_data *ctx;
if (!kvm_arm_support_pmu_v3() || !ctx || !kvm_pmu_switch_needed(attr))
if (!kvm_arm_support_pmu_v3())
return;
ctx = this_cpu_ptr_hyp_sym(kvm_host_data);
if (!ctx || !kvm_pmu_switch_needed(attr))
return;
if (!attr->exclude_host)
@@ -47,9 +51,13 @@ void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr)
*/
void kvm_clr_pmu_events(u32 clr)
{
struct kvm_host_data *ctx = this_cpu_ptr_hyp_sym(kvm_host_data);
struct kvm_host_data *ctx;
if (!kvm_arm_support_pmu_v3() || !ctx)
if (!kvm_arm_support_pmu_v3())
return;
ctx = this_cpu_ptr_hyp_sym(kvm_host_data);
if (!ctx)
return;
ctx->pmu_events.events_host &= ~clr;