On 14/02/2019 16:54, Cornelia Huck wrote:
On Thu, 14 Feb 2019 14:51:02 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
This patch adds interception code for the PQAP instructions,
and a callback inside the KVM arch structure for s390.
If a VFIO-AP drivers needs to intercept PQAP/AQIC or PQAP/TAPQ
s/drivers/driver/
thanks. OK
...
#include "kvm-s390.h"
#include "trace.h"
@@ -592,6 +593,53 @@ static int handle_io_inst(struct kvm_vcpu *vcpu)
}
}
+/*
+ * handle_pqap: Handling pqap interception
+ * @vcpu: the vcpu having issue the pqap instruction
s/issue/issued/
OK. thanks.
+ *
+ * This callback only handles PQAP/AQIC instruction and
Here you only talk about PQAP/AQIC, what about PQAP/TAPQ mentioned in
the patch description?
I can add "for now" or "in this patch" or suppress the reference to
PAPQ/TAPQ
+ * calls a dedicated callback for this instruction if
+ * a driver did register one in the CRYPTO satellite of the
+ * SIE block.
+ *
+ * Do not change the behavior if, return -EOPNOTSUPP if:
+ * - the hook is not used do not change the behavior.
The hook is not used? Or not set?
I think "is not set" is better.
(I don't think you need to repeat "do
not change the behavior".)
OK
+ * - AP instructions are not available or not available to the guest
+ * - the instruction is not PQAP with function code indicating
+ * AQIC do not change the previous behavior.
+ *
+ * For PQAP/AQIC instruction, verify privilege and specifications
+ *
+ * return the value returned by the callback.
+ */
+static int handle_pqap(struct kvm_vcpu *vcpu)
+{
+ uint8_t fc;
+
+ /* Verify that the hook callback is registered */
+ if (!vcpu->kvm->arch.crypto.pqap_hook)
+ return -EOPNOTSUPP;
+ /* Verify that the AP instruction are available */
+ if (!ap_instructions_available())
+ return -EOPNOTSUPP;
+ /* Verify that the guest is allowed to use AP instructions */
+ if (!(vcpu->arch.sie_block->eca & ECA_APIE))
+ return -EOPNOTSUPP;
+ /* Verify that the function code is AQIC */
+ fc = vcpu->run->s.regs.gprs[0] >> 24;
+ if (fc != 0x03)
+ return -EOPNOTSUPP;
+
+ /* PQAP instructions are allowed for guest kernel only */
+ if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
+ return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
+ /* AQIC instruction is allowed only if facility 65 is available */
+ if (!test_kvm_facility(vcpu->kvm, 65))
+ return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+ /* All right, call the callback */
+ return vcpu->kvm->arch.crypto.pqap_hook(vcpu);
Can that callback also return -EOPNOTSUPP to order to drop to user
space?
Yes.
Why not?
+}
+
static int handle_stfl(struct kvm_vcpu *vcpu)
{
int rc;
@@ -878,6 +926,8 @@ int kvm_s390_handle_b2(struct kvm_vcpu *vcpu)
return handle_sthyi(vcpu);
case 0x7d:
return handle_stsi(vcpu);
+ case 0xaf:
+ return handle_pqap(vcpu);
case 0xb1:
return handle_stfl(vcpu);
case 0xb2:
--
Pierre Morel
Linux/KVM/QEMU in Böblingen - Germany
