Commit 46fa8933 authored by Claudio Imbrenda's avatar Claudio Imbrenda Committed by Cornelia Huck
Browse files

s390x: fix storage attributes migration for non-small guests 



Fix storage attribute migration so that it does not fail for guests
with more than a few GB of RAM.
With such guests, the index in the buffer would go out of bounds,
usually by large amounts, thus receiving -EFAULT from the kernel.
Migration itself would be successful, but storage attributes would then
not be migrated completely.

This patch fixes the out of bounds access, and thus migration of all
storage attributes when the guest have large amounts of memory.

Cc: qemu-stable@nongnu.org
Signed-off-by: default avatarClaudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Fixes: 903fd80b ("s390x/migration: Storage attributes device")
Message-Id: <1516297904-18188-1-git-send-email-imbrenda@linux.vnet.ibm.com>
Reviewed-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarCornelia Huck <cohuck@redhat.com>
parent 74a69e03

hw/s390x/s390-stattrib-kvm.c

+2 −2
Original line number Diff line number Diff line
@@ -116,7 +116,7 @@ static void kvm_s390_stattrib_synchronize(S390StAttribState *sa) 
        for (cx = 0; cx + len <= max; cx += len) {

            clog.start_gfn = cx;

            clog.count = len;

            clog.values = (uint64_t)(sas->incoming_buffer + cx * len);

            clog.values = (uint64_t)(sas->incoming_buffer + cx);

            r = kvm_vm_ioctl(kvm_state, KVM_S390_SET_CMMA_BITS, &clog);

            if (r) {

                error_report("KVM_S390_SET_CMMA_BITS failed: %s", strerror(-r));
@@ -126,7 +126,7 @@ static void kvm_s390_stattrib_synchronize(S390StAttribState *sa) 
        if (cx < max) {

            clog.start_gfn = cx;

            clog.count = max - cx;

            clog.values = (uint64_t)(sas->incoming_buffer + cx * len);

            clog.values = (uint64_t)(sas->incoming_buffer + cx);

            r = kvm_vm_ioctl(kvm_state, KVM_S390_SET_CMMA_BITS, &clog);

            if (r) {

                error_report("KVM_S390_SET_CMMA_BITS failed: %s", strerror(-r));