[PATCH 5.9 250/255] powerpc/603: Always fault when _PAGE_ACCESSED is not set

Greg Kroah-Hartman
2020-11-17T13:43:33Z

From: Christophe Leroy <christophe.leroy@csgroup.eu>

commit 11522448e641e8f1690c9db06e01985e8e19b401 upstream.

The kernel expects pte_young() to work regardless of CONFIG_SWAP.

Make sure a minor fault is taken to set _PAGE_ACCESSED when it
is not already set, regardless of the selection of CONFIG_SWAP.

Fixes: 84de6ab0e904 ("powerpc/603: don't handle PAGE_ACCESSED in TLB miss handlers.")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a44367744de54e2315b2f1a8cbbd7f88488072e0.1602342806.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/powerpc/kernel/head_32.S | 12 ------------
1 file changed, 12 deletions(-)

--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -472,11 +472,7 @@ InstructionTLBMiss:
cmplw 0,r1,r3
#endif
mfspr r2, SPRN_SPRG_PGDIR
-#ifdef CONFIG_SWAP
li r1,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
-#else
- li r1,_PAGE_PRESENT | _PAGE_EXEC
-#endif
#if defined(CONFIG_MODULES) || defined(CONFIG_DEBUG_PAGEALLOC)
bgt- 112f
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
@@ -538,11 +534,7 @@ DataLoadTLBMiss:
lis r1, TASK_SIZE@h /* check if kernel address */
cmplw 0,r1,r3
mfspr r2, SPRN_SPRG_PGDIR
-#ifdef CONFIG_SWAP
li r1, _PAGE_PRESENT | _PAGE_ACCESSED
-#else
- li r1, _PAGE_PRESENT
-#endif
bgt- 112f
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */
@@ -618,11 +610,7 @@ DataStoreTLBMiss:
lis r1, TASK_SIZE@h /* check if kernel address */
cmplw 0,r1,r3
mfspr r2, SPRN_SPRG_PGDIR
-#ifdef CONFIG_SWAP
li r1, _PAGE_RW | _PAGE_DIRTY | _PAGE_PRESENT | _PAGE_ACCESSED
-#else
- li r1, _PAGE_RW | _PAGE_DIRTY | _PAGE_PRESENT
-#endif
bgt- 112f
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */