Hi, Bibo,
On Mon, Mar 3, 2025 at 5:11 PM Bibo Mao <maobibo@xxxxxxxxxxx> wrote:
>
> On host HW guest CSR registers are lost after suspend and resume
> operation. Since last_vcpu of boot CPU still records latest vCPU pointer
> so that guest CSR register skips to reload when boot CPU resumes and
> vCPU is scheduled.
>
> Here last_vcpu is cleared so that guest CSR register will reload from
> scheduled vCPU context after suspend and resume.
>
> Also there is another small fix for Loongson AVEC support, bit 14 is added
> in CSR ESTAT register. Macro CSR_ESTAT_IS is replaced with hardcoded value
> 0x1fff and AVEC interrupt status bit 14 is supported with macro
> CSR_ESTAT_IS.
>
> Signed-off-by: Bibo Mao <maobibo@xxxxxxxxxxx>
> ---
> arch/loongarch/kvm/main.c | 8 ++++++++
> arch/loongarch/kvm/vcpu.c | 2 +-
> 2 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/arch/loongarch/kvm/main.c b/arch/loongarch/kvm/main.c
> index f6d3242b9234..b177773f38f6 100644
> --- a/arch/loongarch/kvm/main.c
> +++ b/arch/loongarch/kvm/main.c
> @@ -284,6 +284,7 @@ long kvm_arch_dev_ioctl(struct file *filp,
> int kvm_arch_enable_virtualization_cpu(void)
> {
> unsigned long env, gcfg = 0;
> + struct kvm_context *context;
>
> env = read_csr_gcfg();
>
> @@ -317,6 +318,13 @@ int kvm_arch_enable_virtualization_cpu(void)
> kvm_debug("GCFG:%lx GSTAT:%lx GINTC:%lx GTLBC:%lx",
> read_csr_gcfg(), read_csr_gstat(), read_csr_gintc(), read_csr_gtlbc());
>
> + /*
> + * HW Guest CSR registers are lost after CPU suspend and resume
> + * Clear last_vcpu so that Guest CSR register forced to reload
> + * from vCPU SW state
> + */
> + context = this_cpu_ptr(vmcs);
> + context->last_vcpu = NULL;
This can be simplified as this_cpu_ptr(vmcs)->last_vcpu = NULL;
> return 0;
> }
>
> diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c
> index 20f941af3e9e..9e1a9b4aa4c6 100644
> --- a/arch/loongarch/kvm/vcpu.c
> +++ b/arch/loongarch/kvm/vcpu.c
> @@ -311,7 +311,7 @@ static int kvm_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
> {
> int ret = RESUME_GUEST;
> unsigned long estat = vcpu->arch.host_estat;
> - u32 intr = estat & 0x1fff; /* Ignore NMI */
> + u32 intr = estat & CSR_ESTAT_IS;
This part has nothing to do with S4, please split to another patch.
Huacai
> u32 ecode = (estat & CSR_ESTAT_EXC) >> CSR_ESTAT_EXC_SHIFT;
>
> vcpu->mode = OUTSIDE_GUEST_MODE;
>
> base-commit: 1e15510b71c99c6e49134d756df91069f7d18141
> --
> 2.39.3
>
>
