| Message ID | 1534196899-16987-6-git-send-email-akrowiak@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | guest dedicated crypto adapters | expand |
On Mon, 13 Aug 2018 17:48:02 -0400 Tony Krowiak <akrowiak@linux.vnet.ibm.com> wrote: > From: David Hildenbrand <david@redhat.com> > > VCPU requests and VCPU blocking right now don't take care of the vSIE > (as it was not necessary until now). But we want to have VCPU requests > that will also be handled before running the vSIE again. > > So let's simulate a SIE entry when entering the vSIE loop and check > for PROG_ flags. The existing infrastructure (e.g. exit_sie()) will then > detect that the SIE (in form of the vSIE execution loop) is running and > properly kick the vSIE CPU, resulting in it leaving the vSIE loop and > therefore the vSIE interception handler, allowing it to handle VCPU > requests. > > E.g. if we want to modify the crycb of the VCPU and make sure that any > masks also get applied to the VSIE crycb shadow (which uses masks from the > VCPU crycb), we will need a way to hinder the vSIE from running and make > sure to process the updated crycb before reentering the vSIE again. > > Signed-off-by: David Hildenbrand <david@redhat.com> > Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> > Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> > --- > arch/s390/kvm/kvm-s390.c | 9 ++++++++- > arch/s390/kvm/kvm-s390.h | 1 + > arch/s390/kvm/vsie.c | 20 ++++++++++++++++++-- > 3 files changed, 27 insertions(+), 3 deletions(-) I think that is the RFC version of David's patch, not the v1? Again, not really relevant for reviewing, but I hope that you test the final version.
On 08/14/2018 04:50 AM, Cornelia Huck wrote: > On Mon, 13 Aug 2018 17:48:02 -0400 > Tony Krowiak <akrowiak@linux.vnet.ibm.com> wrote: > >> From: David Hildenbrand <david@redhat.com> >> >> VCPU requests and VCPU blocking right now don't take care of the vSIE >> (as it was not necessary until now). But we want to have VCPU requests >> that will also be handled before running the vSIE again. >> >> So let's simulate a SIE entry when entering the vSIE loop and check >> for PROG_ flags. The existing infrastructure (e.g. exit_sie()) will then >> detect that the SIE (in form of the vSIE execution loop) is running and >> properly kick the vSIE CPU, resulting in it leaving the vSIE loop and >> therefore the vSIE interception handler, allowing it to handle VCPU >> requests. >> >> E.g. if we want to modify the crycb of the VCPU and make sure that any >> masks also get applied to the VSIE crycb shadow (which uses masks from the >> VCPU crycb), we will need a way to hinder the vSIE from running and make >> sure to process the updated crycb before reentering the vSIE again. >> >> Signed-off-by: David Hildenbrand <david@redhat.com> >> Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> >> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> >> --- >> arch/s390/kvm/kvm-s390.c | 9 ++++++++- >> arch/s390/kvm/kvm-s390.h | 1 + >> arch/s390/kvm/vsie.c | 20 ++++++++++++++++++-- >> 3 files changed, 27 insertions(+), 3 deletions(-) > I think that is the RFC version of David's patch, not the v1? Again, > not really relevant for reviewing, but I hope that you test the final > version. Will do. >
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 3b7a515..6df2d12 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -2655,18 +2655,25 @@ static void kvm_s390_vcpu_request(struct kvm_vcpu *vcpu) exit_sie(vcpu); } +bool kvm_s390_vcpu_sie_inhibited(struct kvm_vcpu *vcpu) +{ + return atomic_read(&vcpu->arch.sie_block->prog20) & + (PROG_BLOCK_SIE | PROG_REQUEST); +} + static void kvm_s390_vcpu_request_handled(struct kvm_vcpu *vcpu) { atomic_andnot(PROG_REQUEST, &vcpu->arch.sie_block->prog20); } /* - * Kick a guest cpu out of SIE and wait until SIE is not running. + * Kick a guest cpu out of (v)SIE and wait until (v)SIE is not running. * If the CPU is not running (e.g. waiting as idle) the function will * return immediately. */ void exit_sie(struct kvm_vcpu *vcpu) { kvm_s390_set_cpuflags(vcpu, CPUSTAT_STOP_INT); + kvm_s390_vsie_kick(vcpu); while (vcpu->arch.sie_block->prog0c & PROG_IN_SIE) cpu_relax(); } diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h index 981e3ba..1f6e36c 100644 --- a/arch/s390/kvm/kvm-s390.h +++ b/arch/s390/kvm/kvm-s390.h @@ -290,6 +290,7 @@ void kvm_s390_set_tod_clock(struct kvm *kvm, void kvm_s390_vcpu_stop(struct kvm_vcpu *vcpu); void kvm_s390_vcpu_block(struct kvm_vcpu *vcpu); void kvm_s390_vcpu_unblock(struct kvm_vcpu *vcpu); +bool kvm_s390_vcpu_sie_inhibited(struct kvm_vcpu *vcpu); void exit_sie(struct kvm_vcpu *vcpu); void kvm_s390_sync_request(int req, struct kvm_vcpu *vcpu); int kvm_s390_vcpu_setup_cmma(struct kvm_vcpu *vcpu); diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c index 84c89cb..aa30b48 100644 --- a/arch/s390/kvm/vsie.c +++ b/arch/s390/kvm/vsie.c @@ -982,6 +982,17 @@ static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s; int rc = 0; + /* + * Simulate a SIE entry of the VCPU (see sie64a), so VCPU blocking + * and VCPU requests can hinder the whole vSIE loop from running + * and lead to an immediate exit. We do it at this point (not + * earlier), so kvm_s390_vsie_kick() works correctly already. + */ + vcpu->arch.sie_block->prog0c |= PROG_IN_SIE; + barrier(); + if (kvm_s390_vcpu_sie_inhibited(vcpu)) + return 0; + while (1) { rc = acquire_gmap_shadow(vcpu, vsie_page); if (!rc) @@ -997,10 +1008,14 @@ static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) if (rc == -EAGAIN) rc = 0; if (rc || scb_s->icptcode || signal_pending(current) || - kvm_s390_vcpu_has_irq(vcpu, 0)) + kvm_s390_vcpu_has_irq(vcpu, 0) || + kvm_s390_vcpu_sie_inhibited(vcpu)) break; } + barrier(); + vcpu->arch.sie_block->prog0c &= ~PROG_IN_SIE; + if (rc == -EFAULT) { /* * Addressing exceptions are always presentes as intercepts. @@ -1114,7 +1129,8 @@ int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu) if (unlikely(scb_addr & 0x1ffUL)) return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); - if (signal_pending(current) || kvm_s390_vcpu_has_irq(vcpu, 0)) + if (signal_pending(current) || kvm_s390_vcpu_has_irq(vcpu, 0) || + kvm_s390_vcpu_sie_inhibited(vcpu)) return 0; vsie_page = get_vsie_page(vcpu->kvm, scb_addr);