From: Scott Wood <scottwood@freescale.com>
To: paulus@samba.org
Cc: linuxppc-dev@ozlabs.org
Subject: [PATCH] Check _PAGE_RW and _PAGE_PRESENT on kernel addresses.
Date: Tue, 21 Aug 2007 16:10:48 -0500 [thread overview]
Message-ID: <20070821211048.GA8432@ld0162-tx32.am.freescale.net> (raw)
Previously, the TLB miss handlers assumed that pages above KERNELBASE are
always present and read/write. This assumption is false in the case of
CONFIG_DEBUG_PAGEALLOC.
Signed-off-by: Scott Wood <scottwood@freescale.com>
---
arch/powerpc/kernel/head_32.S | 12 ++++++------
1 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 7d73a13..2d3b804 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -475,10 +475,10 @@ InstructionTLBMiss:
li r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
lwz r2,PGDIR(r2)
blt+ 112f
+ mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
+ rlwinm r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
lis r2,swapper_pg_dir@ha /* if kernel address, use */
addi r2,r2,swapper_pg_dir@l /* kernel page table */
- mfspr r1,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
- rlwinm r1,r1,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
112: tophys(r2,r2)
rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
lwz r2,0(r2) /* get pmd entry */
@@ -549,10 +549,10 @@ DataLoadTLBMiss:
li r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
lwz r2,PGDIR(r2)
blt+ 112f
+ mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
+ rlwinm r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
lis r2,swapper_pg_dir@ha /* if kernel address, use */
addi r2,r2,swapper_pg_dir@l /* kernel page table */
- mfspr r1,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
- rlwinm r1,r1,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
112: tophys(r2,r2)
rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
lwz r2,0(r2) /* get pmd entry */
@@ -621,10 +621,10 @@ DataStoreTLBMiss:
li r1,_PAGE_RW|_PAGE_USER|_PAGE_PRESENT /* access flags */
lwz r2,PGDIR(r2)
blt+ 112f
+ mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
+ rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
lis r2,swapper_pg_dir@ha /* if kernel address, use */
addi r2,r2,swapper_pg_dir@l /* kernel page table */
- mfspr r1,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
- rlwinm r1,r1,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
112: tophys(r2,r2)
rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
lwz r2,0(r2) /* get pmd entry */
--
1.5.0.3
next reply other threads:[~2007-08-21 21:10 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-08-21 21:10 Scott Wood [this message]
2007-08-22 3:52 ` [PATCH] Check _PAGE_RW and _PAGE_PRESENT on kernel addresses Paul Mackerras
2007-08-22 4:22 ` Scott Wood
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