[3.19.y-ckt stable] Patch "x86/mm: Fix types used in pgprot cacheability flags translations" has been added to the 3.19.y-ckt tree

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    x86/mm: Fix types used in pgprot cacheability flags translations

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt15.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

>From c9f9676be42eb11a410407d3821fc28dcae8ab4e Mon Sep 17 00:00:00 2001
From: Jan Beulich <JBeulich at suse.com>
Date: Tue, 26 Jan 2016 04:15:18 -0700
Subject: x86/mm: Fix types used in pgprot cacheability flags translations

commit 3625c2c234ef66acf21a72d47a5ffa94f6c5ebf2 upstream.

For PAE kernels "unsigned long" is not suitable to hold page protection
flags, since _PAGE_NX doesn't fit there. This is the reason for quite a
few W+X pages getting reported as insecure during boot (observed namely
for the entire initrd range).

Fixes: 281d4078be ("x86: Make page cache mode a real type")
Signed-off-by: Jan Beulich <jbeulich at suse.com>
Reviewed-by: Juergen Gross <JGross at suse.com>
Link: http://lkml.kernel.org/r/56A7635602000078000CAFF1@prv-mh.provo.novell.com
Signed-off-by: Thomas Gleixner <tglx at linutronix.de>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 arch/x86/include/asm/pgtable_types.h | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index 25bcd4a..e592881 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -377,20 +377,18 @@ static inline enum page_cache_mode pgprot2cachemode(pgprot_t pgprot)
 }
 static inline pgprot_t pgprot_4k_2_large(pgprot_t pgprot)
 {
+	pgprotval_t val = pgprot_val(pgprot);
 	pgprot_t new;
-	unsigned long val;

-	val = pgprot_val(pgprot);
 	pgprot_val(new) = (val & ~(_PAGE_PAT | _PAGE_PAT_LARGE)) |
 		((val & _PAGE_PAT) << (_PAGE_BIT_PAT_LARGE - _PAGE_BIT_PAT));
 	return new;
 }
 static inline pgprot_t pgprot_large_2_4k(pgprot_t pgprot)
 {
+	pgprotval_t val = pgprot_val(pgprot);
 	pgprot_t new;
-	unsigned long val;

-	val = pgprot_val(pgprot);
 	pgprot_val(new) = (val & ~(_PAGE_PAT | _PAGE_PAT_LARGE)) |
 			  ((val & _PAGE_PAT_LARGE) >>
 			   (_PAGE_BIT_PAT_LARGE - _PAGE_BIT_PAT));
--
1.9.1