Jan Beulich
2012-Jun-20 15:18 UTC
[PATCH] x86/mm: fix mod_l1_entry() return value when encountering r/o MMIO page
While putting together the workaround announced in
http://lists.xen.org/archives/html/xen-devel/2012-06/msg00709.html, I
found that mod_l1_entry(), upon encountering a set bit in
mmio_ro_ranges, would return 1 instead of 0 (the removal of the write
permission is supposed to be entirely transparent to the caller, even
more so to the calling guest).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -1875,6 +1875,7 @@ static int mod_l1_entry(l1_pgentry_t *pl
break;
case 1:
l1e_remove_flags(nl1e, _PAGE_RW);
+ rc = 0;
break;
}
if ( page )
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Keir Fraser
2012-Jun-20 16:04 UTC
Re: [PATCH] x86/mm: fix mod_l1_entry() return value when encountering r/o MMIO page
On 20/06/2012 16:18, "Jan Beulich" <JBeulich@suse.com> wrote:> While putting together the workaround announced in > http://lists.xen.org/archives/html/xen-devel/2012-06/msg00709.html, I > found that mod_l1_entry(), upon encountering a set bit in > mmio_ro_ranges, would return 1 instead of 0 (the removal of the write > permission is supposed to be entirely transparent to the caller, even > more so to the calling guest). > > Signed-off-by: Jan Beulich <jbeulich@suse.com>Acked-by: Keir Fraser <keir@xen.org>> --- a/xen/arch/x86/mm.c > +++ b/xen/arch/x86/mm.c > @@ -1875,6 +1875,7 @@ static int mod_l1_entry(l1_pgentry_t *pl > break; > case 1: > l1e_remove_flags(nl1e, _PAGE_RW); > + rc = 0; > break; > } > if ( page ) > > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel