On Tue, 2 Feb 2021 19:00:28 +0100 Claudio Imbrenda imbrenda@linux.ibm.com wrote:
Correctly handle the MVPG instruction when issued by a VSIE guest.
Fixes: a3508fbe9dc6d ("KVM: s390: vsie: initial support for nested virtualization") Cc: stable@vger.kernel.org Signed-off-by: Claudio Imbrenda imbrenda@linux.ibm.com
arch/s390/kvm/vsie.c | 94 +++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 89 insertions(+), 5 deletions(-)
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c index 7db022141db3..2db49749e27b 100644 --- a/arch/s390/kvm/vsie.c +++ b/arch/s390/kvm/vsie.c @@ -416,11 +416,6 @@ static void unshadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) memcpy((void *)((u64)scb_o + 0xc0), (void *)((u64)scb_s + 0xc0), 0xf0 - 0xc0); break;
- case ICPT_PARTEXEC:
/* MVPG only */memcpy((void *)((u64)scb_o + 0xc0),(void *)((u64)scb_s + 0xc0), 0xd0 - 0xc0);break;if (scb_s->ihcpu != 0xffffU) @@ -982,6 +977,91 @@ static int handle_stfle(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) return 0; } +static u64 vsie_get_register(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page, u8 reg) +{
- reg &= 0xf;
- switch (reg) {
- case 15:
return vsie_page->scb_s.gg15;- case 14:
return vsie_page->scb_s.gg14;- default:
return vcpu->run->s.regs.gprs[reg];- }
+}
+static int vsie_handle_mvpg(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) +{
- struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
- unsigned long pei1, pei2, src, dest, mask = PAGE_MASK;
- u64 *pei_block = &vsie_page->scb_o->mcic;
- int edat, rc1, rc2;
- union ctlreg0 cr0;
- cr0.val = vcpu->arch.sie_block->gcr[0];
- edat = cr0.edat && test_kvm_facility(vcpu->kvm, 8);
- if (psw_bits(scb_s->gpsw).eaba == PSW_BITS_AMODE_24BIT)
mask = 0xfff000;- else if (psw_bits(scb_s->gpsw).eaba == PSW_BITS_AMODE_31BIT)
mask = 0x7ffff000;- dest = vsie_get_register(vcpu, vsie_page, scb_s->ipb >> 16)
& mask;
- src = vsie_get_register(vcpu, vsie_page, scb_s->ipb >> 20) &
mask; +
- rc1 = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, dest,
&pei1);
- rc2 = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, src,
&pei2);
- /*
* Either everything went well, or something non-criticalwent wrong
* e.g. beause of a race. In either case, simply retry.*/- if (rc1 == -EAGAIN || rc2 == -EAGAIN || (!rc1 && !rc2)) {
retry_vsie_icpt(vsie_page);return -EAGAIN;- }
- /* Something more serious went wrong, propagate the error */
- if (rc1 < 0)
return rc1;- if (rc2 < 0)
return rc2;- /* The only possible suppressing exception: just deliver it
*/
- if (rc1 == PGM_TRANSLATION_SPEC || rc2 ==
PGM_TRANSLATION_SPEC) {
clear_vsie_icpt(vsie_page);rc1 = kvm_s390_inject_program_int(vcpu,PGM_TRANSLATION_SPEC);
WARN_ON_ONCE(rc1);return 1;- }
- /*
* Forward the PEI intercept to the guest if it was a pagefault, or
* also for segment and region table faults if EDAT applies.*/- if (edat) {
rc1 = rc1 == PGM_ASCE_TYPE ? rc1 : 0;rc2 = rc2 == PGM_ASCE_TYPE ? rc2 : 0;- }
I just noticed, this should actually be:
if (edat) { rc1 = rc1 == PGM_ASCE_TYPE ? rc1 : 0; rc2 = rc2 == PGM_ASCE_TYPE ? rc2 : 0; } else { rc1 = rc1 != PGM_PAGE_TRANSLATION ? rc1 : 0; rc2 = rc2 != PGM_PAGE_TRANSLATION ? rc2 : 0; }
I'll fix it in the next version
- if ((!rc1 || rc1 == PGM_PAGE_TRANSLATION) && (!rc2 || rc2 ==
PGM_PAGE_TRANSLATION)) {
pei_block[0] = pei1;pei_block[1] = pei2;return 1;- }
- retry_vsie_icpt(vsie_page);
- /*
* The host has edat, and the guest does not, or it was anASCE type
* exception. The host needs to inject the appropriate DATinterrupts
* into the guest.*/- if (rc1)
return inject_fault(vcpu, rc1, dest, 1);- if (rc2)
return inject_fault(vcpu, rc2, src, 0);- /* This should never be reached */
- return 0;
+}
/*
- Run the vsie on a shadow scb and a shadow gmap, without any
further
- sanity checks, handling SIE faults.
@@ -1068,6 +1148,10 @@ static int do_vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) if ((scb_s->ipa & 0xf000) != 0xf000) scb_s->ipa += 0x1000; break;
- case ICPT_PARTEXEC:
if (scb_s->ipa == 0xb254)rc = vsie_handle_mvpg(vcpu, vsie_page);break;}