diff options
| author | Thomas Huth <thuth@linux.vnet.ibm.com> | 2014-01-15 16:46:07 +0100 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2014-05-06 14:58:10 +0200 |
| commit | f14d82e06a008b8977b64866a4907d2e152af939 (patch) | |
| tree | cff2c7389cb1afd202a49f1a3be476e5ad9c12cb /arch/s390/kvm/intercept.c | |
| parent | e029ae5b787e08e976a683c6a45fac20fc227447 (diff) | |
KVM: s390: Fix external interrupt interception
The external interrupt interception can only occur in rare cases, e.g.
when the PSW of the interrupt handler has a bad value. The old handler
for this interception simply ignored these events (except for increasing
the exit_external_interrupt counter), but for proper operation we either
have to inject the interrupts manually or we should drop to userspace in
case of errors.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Diffstat (limited to 'arch/s390/kvm/intercept.c')
| -rw-r--r-- | arch/s390/kvm/intercept.c | 49 |
1 files changed, 45 insertions, 4 deletions
diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c index 99e4b76e3487..bd607cf01a5d 100644 --- a/arch/s390/kvm/intercept.c +++ b/arch/s390/kvm/intercept.c @@ -17,6 +17,7 @@ #include <asm/kvm_host.h> #include <asm/asm-offsets.h> +#include <asm/irq.h> #include "kvm-s390.h" #include "gaccess.h" @@ -46,9 +47,6 @@ static int handle_noop(struct kvm_vcpu *vcpu) case 0x10: vcpu->stat.exit_external_request++; break; - case 0x14: - vcpu->stat.exit_external_interrupt++; - break; default: break; /* nothing */ } @@ -234,6 +232,49 @@ static int handle_instruction_and_prog(struct kvm_vcpu *vcpu) } /** + * handle_external_interrupt - used for external interruption interceptions + * + * This interception only occurs if the CPUSTAT_EXT_INT bit was set, or if + * the new PSW does not have external interrupts disabled. In the first case, + * we've got to deliver the interrupt manually, and in the second case, we + * drop to userspace to handle the situation there. + */ +static int handle_external_interrupt(struct kvm_vcpu *vcpu) +{ + u16 eic = vcpu->arch.sie_block->eic; + struct kvm_s390_interrupt irq; + psw_t newpsw; + int rc; + + vcpu->stat.exit_external_interrupt++; + + rc = read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &newpsw, sizeof(psw_t)); + if (rc) + return rc; + /* We can not handle clock comparator or timer interrupt with bad PSW */ + if ((eic == EXT_IRQ_CLK_COMP || eic == EXT_IRQ_CPU_TIMER) && + (newpsw.mask & PSW_MASK_EXT)) + return -EOPNOTSUPP; + + switch (eic) { + case EXT_IRQ_CLK_COMP: + irq.type = KVM_S390_INT_CLOCK_COMP; + break; + case EXT_IRQ_CPU_TIMER: + irq.type = KVM_S390_INT_CPU_TIMER; + break; + case EXT_IRQ_EXTERNAL_CALL: + irq.type = KVM_S390_INT_EXTERNAL_CALL; + irq.parm = vcpu->arch.sie_block->extcpuaddr; + break; + default: + return -EOPNOTSUPP; + } + + return kvm_s390_inject_vcpu(vcpu, &irq); +} + +/** * Handle MOVE PAGE partial execution interception. * * This interception can only happen for guests with DAT disabled and @@ -291,7 +332,7 @@ static const intercept_handler_t intercept_funcs[] = { [0x08 >> 2] = handle_prog, [0x0C >> 2] = handle_instruction_and_prog, [0x10 >> 2] = handle_noop, - [0x14 >> 2] = handle_noop, + [0x14 >> 2] = handle_external_interrupt, [0x18 >> 2] = handle_noop, [0x1C >> 2] = kvm_s390_handle_wait, [0x20 >> 2] = handle_validity, |