KVM: s390: VSIE: correctly handle MVPG when in VSIE

commit bdf7509bbefa20855d5f6bacdc5b62a8489477c9 upstream.

Correctly handle the MVPG instruction when issued by a VSIE guest.

Fixes: a3508fbe9d ("KVM: s390: vsie: initial support for nested virtualization")
Cc: stable@vger.kernel.org # f85f1baaa189: KVM: s390: split kvm_s390_logical_to_effective
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Link: https://lore.kernel.org/r/20210302174443.514363-4-imbrenda@linux.ibm.com
[borntraeger@de.ibm.com: apply fixup from Claudio]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Claudio Imbrenda 2021-02-01 21:54:13 +01:00 committed by Greg Kroah-Hartman
parent 885024a8fb
commit 82de9ad493

View File

@ -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 +977,95 @@ static int handle_stfle(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
return 0;
}
/*
* Get a register for a nested guest.
* @vcpu the vcpu of the guest
* @vsie_page the vsie_page for the nested guest
* @reg the register number, the upper 4 bits are ignored.
* returns: the value of the register.
*/
static u64 vsie_get_register(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page, u8 reg)
{
/* no need to validate the parameter and/or perform error handling */
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 pei_dest, pei_src, src, dest, mask;
u64 *pei_block = &vsie_page->scb_o->mcic;
int edat, rc_dest, rc_src;
union ctlreg0 cr0;
cr0.val = vcpu->arch.sie_block->gcr[0];
edat = cr0.edat && test_kvm_facility(vcpu->kvm, 8);
mask = _kvm_s390_logical_to_effective(&scb_s->gpsw, PAGE_MASK);
dest = vsie_get_register(vcpu, vsie_page, scb_s->ipb >> 20) & mask;
src = vsie_get_register(vcpu, vsie_page, scb_s->ipb >> 16) & mask;
rc_dest = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, dest, &pei_dest);
rc_src = kvm_s390_shadow_fault(vcpu, vsie_page->gmap, src, &pei_src);
/*
* Either everything went well, or something non-critical went wrong
* e.g. because of a race. In either case, simply retry.
*/
if (rc_dest == -EAGAIN || rc_src == -EAGAIN || (!rc_dest && !rc_src)) {
retry_vsie_icpt(vsie_page);
return -EAGAIN;
}
/* Something more serious went wrong, propagate the error */
if (rc_dest < 0)
return rc_dest;
if (rc_src < 0)
return rc_src;
/* The only possible suppressing exception: just deliver it */
if (rc_dest == PGM_TRANSLATION_SPEC || rc_src == PGM_TRANSLATION_SPEC) {
clear_vsie_icpt(vsie_page);
rc_dest = kvm_s390_inject_program_int(vcpu, PGM_TRANSLATION_SPEC);
WARN_ON_ONCE(rc_dest);
return 1;
}
/*
* Forward the PEI intercept to the guest if it was a page fault, or
* also for segment and region table faults if EDAT applies.
*/
if (edat) {
rc_dest = rc_dest == PGM_ASCE_TYPE ? rc_dest : 0;
rc_src = rc_src == PGM_ASCE_TYPE ? rc_src : 0;
} else {
rc_dest = rc_dest != PGM_PAGE_TRANSLATION ? rc_dest : 0;
rc_src = rc_src != PGM_PAGE_TRANSLATION ? rc_src : 0;
}
if (!rc_dest && !rc_src) {
pei_block[0] = pei_dest;
pei_block[1] = pei_src;
return 1;
}
retry_vsie_icpt(vsie_page);
/*
* The host has edat, and the guest does not, or it was an ASCE type
* exception. The host needs to inject the appropriate DAT interrupts
* into the guest.
*/
if (rc_dest)
return inject_fault(vcpu, rc_dest, dest, 1);
return inject_fault(vcpu, rc_src, src, 0);
}
/*
* Run the vsie on a shadow scb and a shadow gmap, without any further
* sanity checks, handling SIE faults.
@ -1068,6 +1152,10 @@ 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;
}
return rc;
}