diff options
| author |   SeungJu Cheon <suunj1331@gmail.com> | 2026-08-25 17:37:18 +0900 |
|---|---|---|
| committer |   Anup Patel <anup@brainfault.org> | 2026-09-15 18:55:51 +0530 |
| commit | 057dd2639ceae79adced5d8fe52c32d562edcb3a (patch) | |
| tree | e75825f948f5d6f0f954517c2799002d6ab4aa9d | |
| parent | RISC-V: KVM: Preserve firmware counter value across stop/start (diff) | |
RISC-V: KVM: Report snapshot write failure to the guest
If kvm_vcpu_write_guest() fails while updating the PMU snapshot area
on counter stop, the guest may receive SBI_SUCCESS without the
snapshot being updated, leaving stale data in shared memory.
Return SBI_ERR_FAILURE when the snapshot write fails.
Fixes: c2f41ddbcdd7 ("RISC-V: KVM: Implement SBI PMU Snapshot feature")
Signed-off-by: SeungJu Cheon <suunj1331@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20260825083719.643970-3-suunj1331@gmail.com
Signed-off-by: Anup Patel <anup@brainfault.org>
| -rw-r--r-- | arch/riscv/kvm/vcpu_pmu.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/arch/riscv/kvm/vcpu_pmu.c b/arch/riscv/kvm/vcpu_pmu.c index 5dfe2054d12b..8be87f879473 100644 --- a/arch/riscv/kvm/vcpu_pmu.c +++ b/arch/riscv/kvm/vcpu_pmu.c @@ -735,9 +735,10 @@ int kvm_riscv_vcpu_pmu_ctr_stop(struct kvm_vcpu *vcpu, unsigned long ctr_base, } } - if (shmem_needs_update) - kvm_vcpu_write_guest(vcpu, kvpmu->snapshot_addr, kvpmu->sdata, - sizeof(struct riscv_pmu_snapshot_data)); + if (shmem_needs_update && + kvm_vcpu_write_guest(vcpu, kvpmu->snapshot_addr, kvpmu->sdata, + sizeof(struct riscv_pmu_snapshot_data))) + sbiret = SBI_ERR_FAILURE; out: retdata->err_val = sbiret; |