3.19-stable patches

added patches:
	x86-xen-p2m-replace-access_once-with-read_once.patch

diff --git a/queue-3.19/series b/queue-3.19/series
index 87233685ea917ce0eb9cc7fa30fe597052c9f449..58226a5a53d9ff88def49e10dc4cb50d85b97b6e 100644 (file)
--- a/queue-3.19/series
+++ b/queue-3.19/series
@@ -172,3 +172,4 @@ kernel-tighten-rules-for-access-once.patch
 kernel-fix-sparse-warning-for-access_once.patch
 kernel-make-read_once-valid-on-const-arguments.patch
 x86-spinlocks-paravirt-fix-memory-corruption-on-unlock.patch
+x86-xen-p2m-replace-access_once-with-read_once.patch

diff --git a/queue-3.19/x86-xen-p2m-replace-access_once-with-read_once.patch b/queue-3.19/x86-xen-p2m-replace-access_once-with-read_once.patch
new file mode 100644 (file)
index 0000000..e072658
--- /dev/null
+++ b/queue-3.19/x86-xen-p2m-replace-access_once-with-read_once.patch
@@ -0,0 +1,36 @@
+From 1760f1eb7ec485197bd3a8a9c13e4160bb740275 Mon Sep 17 00:00:00 2001
+From: Christian Borntraeger <borntraeger@de.ibm.com>
+Date: Sun, 7 Dec 2014 22:01:59 +0100
+Subject: x86/xen/p2m: Replace ACCESS_ONCE with READ_ONCE
+
+From: Christian Borntraeger <borntraeger@de.ibm.com>
+
+commit 1760f1eb7ec485197bd3a8a9c13e4160bb740275 upstream.
+
+ACCESS_ONCE does not work reliably on non-scalar types. For
+example gcc 4.6 and 4.7 might remove the volatile tag for such
+accesses during the SRA (scalar replacement of aggregates) step
+(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)
+
+Change the p2m code to replace ACCESS_ONCE with READ_ONCE.
+
+Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
+Reviewed-by: Juergen Gross <jgross@suse.com>
+Acked-by: David Vrabel <david.vrabel@citrix.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ arch/x86/xen/p2m.c |    2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/arch/x86/xen/p2m.c
++++ b/arch/x86/xen/p2m.c
+@@ -554,7 +554,7 @@ static bool alloc_p2m(unsigned long pfn)
+               mid_mfn = NULL;
+       }
+ 
+-      p2m_pfn = pte_pfn(ACCESS_ONCE(*ptep));
++      p2m_pfn = pte_pfn(READ_ONCE(*ptep));
+       if (p2m_pfn == PFN_DOWN(__pa(p2m_identity)) ||
+           p2m_pfn == PFN_DOWN(__pa(p2m_missing))) {
+               /* p2m leaf page is missing */