Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
KVM: s390: vsie: Fix check for pre-existing shadow mapping
When shadowing a nested guest, a check is performed and no shadowing is
attempted if the nested guest is already shadowed.
The existing check was incomplete; fix it by also checking whether the
leaf DAT table entry in the existing shadow gmap has the same protection
as the one specified in the guest DAT entry.
Fixes: e38c884df921 ("KVM: s390: Switch to new gmap")
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
+3
-2
+3
-2
arch/s390/kvm/gaccess.c
+3
-2
arch/s390/kvm/gaccess.c
···
1506
1506
if (rc)
1507
1507
return rc;
1508
1508
1509
-
/* A race occourred. The shadow mapping is already valid, nothing to do */
1510
-
if ((ptep && !ptep->h.i) || (!ptep && crste_leaf(*table)))
1509
+
/* A race occurred. The shadow mapping is already valid, nothing to do */
1510
+
if ((ptep && !ptep->h.i && ptep->h.p == w->p) ||
1511
+
(!ptep && crste_leaf(*table) && !table->h.i && table->h.p == w->p))
1511
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return 0;
1512
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1514
gl = get_level(table, ptep);