From ff5dc1492a11a6c90955ab34063be1cddc54ec00 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Wed, 14 Oct 2015 16:57:56 +0200 Subject: KVM: s390: fix delivery of vector regs during machine checks Vector registers are only to be stored if the facility is available and if the guest has set up the machine check extended save area. If anything goes wrong while writing the vector registers, the vector registers are to be marked as invalid. Please note that we are allowed to write the registers although they are marked as invalid. Machine checks and "store status" SIGP orders are two different concepts, let's correctly separate these. As the SIGP part is completely handled in user space, we can drop it. This patch is based on a patch from Cornelia Huck. Reviewed-by: Cornelia Huck Signed-off-by: David Hildenbrand Signed-off-by: Christian Borntraeger --- arch/s390/kvm/interrupt.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) (limited to 'arch/s390/kvm/interrupt.c') diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index 84d6dc6..c0ef625 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -25,6 +25,7 @@ #include #include #include +#include #include "kvm-s390.h" #include "gaccess.h" #include "trace-s390.h" @@ -406,8 +407,10 @@ static int __write_machine_check(struct kvm_vcpu *vcpu, { unsigned long ext_sa_addr; freg_t fprs[NUM_FPRS]; + union mci mci; int rc; + mci.val = mchk->mcic; /* take care of lazy register loading via vcpu load/put */ save_fpu_regs(); save_access_regs(vcpu->run->s.regs.acrs); @@ -415,7 +418,15 @@ static int __write_machine_check(struct kvm_vcpu *vcpu, /* Extended save area */ rc = read_guest_lc(vcpu, __LC_VX_SAVE_AREA_ADDR, &ext_sa_addr, sizeof(unsigned long)); - rc |= kvm_s390_vcpu_store_adtl_status(vcpu, ext_sa_addr); + /* Only bits 0-53 are used for address formation */ + ext_sa_addr &= ~0x3ffUL; + if (!rc && mci.vr && ext_sa_addr && test_kvm_facility(vcpu->kvm, 129)) { + if (write_guest_abs(vcpu, ext_sa_addr, vcpu->run->s.regs.vrs, + 512)) + mci.vr = 0; + } else { + mci.vr = 0; + } /* General interruption information */ rc |= put_guest_lc(vcpu, 1, (u8 __user *) __LC_AR_MODE_ID); @@ -423,7 +434,7 @@ static int __write_machine_check(struct kvm_vcpu *vcpu, &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); rc |= read_guest_lc(vcpu, __LC_MCK_NEW_PSW, &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); - rc |= put_guest_lc(vcpu, mchk->mcic, (u64 __user *) __LC_MCCK_CODE); + rc |= put_guest_lc(vcpu, mci.val, (u64 __user *) __LC_MCCK_CODE); /* Register-save areas */ if (MACHINE_HAS_VX) { -- cgit v1.1