Re: [PATCH 1/2] KVM: s390: Fix lpsw/e breaking event handling

Claudio Imbrenda
2026-03-25T12:00:48Z

On Mon, 23 Mar 2026 15:35:22 +0000
Janosch Frank <frankja@linux.ibm.com> wrote:

> LPSW and LPSWE need to set the gbea on completion but currently don't.
> Time to fix this up.
>
> LPSWEY was designed to not set the bear.
>
> Fixes: 48a3e950f4cee ("KVM: s390: Add support for machine checks.")
> Reported-by: Christian Borntraeger <borntraeger@linux.ibm.com>
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>

> ---
> arch/s390/kvm/priv.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
> index a3250ad83a8e..cc0553da14cb 100644
> --- a/arch/s390/kvm/priv.c
> +++ b/arch/s390/kvm/priv.c
> @@ -714,12 +714,13 @@ int kvm_s390_handle_lpsw(struct kvm_vcpu *vcpu)
> {
> psw_t *gpsw = &vcpu->arch.sie_block->gpsw;
> psw32_t new_psw;
> - u64 addr;
> + u64 addr, iaddr;
> int rc;
> u8 ar;
>
> vcpu->stat.instruction_lpsw++;
>
> + iaddr = gpsw->addr - kvm_s390_get_ilen(vcpu);
> if (gpsw->mask & PSW_MASK_PSTATE)
> return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
>
> @@ -737,18 +738,20 @@ int kvm_s390_handle_lpsw(struct kvm_vcpu *vcpu)
> gpsw->addr = new_psw.addr & ~PSW32_ADDR_AMODE;
> if (!is_valid_psw(gpsw))
> return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
> + vcpu->arch.sie_block->gbea = iaddr;
> return 0;
> }
>
> static int handle_lpswe(struct kvm_vcpu *vcpu)
> {
> psw_t new_psw;
> - u64 addr;
> + u64 addr, iaddr;
> int rc;
> u8 ar;
>
> vcpu->stat.instruction_lpswe++;
>
> + iaddr = vcpu->arch.sie_block->gpsw.addr - kvm_s390_get_ilen(vcpu);
> if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
> return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
>
> @@ -761,6 +764,7 @@ static int handle_lpswe(struct kvm_vcpu *vcpu)
> vcpu->arch.sie_block->gpsw = new_psw;
> if (!is_valid_psw(&vcpu->arch.sie_block->gpsw))
> return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
> + vcpu->arch.sie_block->gbea = iaddr;
> return 0;
> }
>