diff options
| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2020-05-20 10:23:45 +0000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-05-20 22:35:52 +1000 |
| commit | 40bb0e904212cf7d6f041a98c58c8341b2016670 (patch) | |
| tree | 84f39dab91463e841a6292a2329de436595415f3 /arch/powerpc/mm | |
| parent | 249c9b0cd193d983c3a0b00f3fd3b92333bfeebe (diff) | |
| download | linux-40bb0e904212cf7d6f041a98c58c8341b2016670.tar.bz2 | |
Revert "powerpc/32s: reorder Linux PTE bits to better match Hash PTE bits."
This reverts commit 697ece78f8f749aeea40f2711389901f0974017a.
The implementation of SWAP on powerpc requires page protection
bits to not be one of the least significant PTE bits.
Until the SWAP implementation is changed and this requirement voids,
we have to keep at least _PAGE_RW outside of the 3 last bits.
For now, revert to previous PTE bits order. A further rework
may come later.
Fixes: 697ece78f8f7 ("powerpc/32s: reorder Linux PTE bits to better match Hash PTE bits.")
Reported-by: Rui Salvaterra <rsalvaterra@gmail.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b34706f8de87f84d135abb5f3ede6b6f16fb1f41.1589969799.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/mm')
| -rw-r--r-- | arch/powerpc/mm/book3s32/hash_low.S | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/arch/powerpc/mm/book3s32/hash_low.S b/arch/powerpc/mm/book3s32/hash_low.S index 6d236080cb1a..877d880890fe 100644 --- a/arch/powerpc/mm/book3s32/hash_low.S +++ b/arch/powerpc/mm/book3s32/hash_low.S @@ -35,7 +35,7 @@ mmu_hash_lock: /* * Load a PTE into the hash table, if possible. * The address is in r4, and r3 contains an access flag: - * _PAGE_RW (0x002) if a write. + * _PAGE_RW (0x400) if a write. * r9 contains the SRR1 value, from which we use the MSR_PR bit. * SPRG_THREAD contains the physical address of the current task's thread. * @@ -69,7 +69,7 @@ _GLOBAL(hash_page) blt+ 112f /* assume user more likely */ lis r5, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */ addi r5 ,r5 ,(swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */ - rlwimi r3,r9,32-14,31,31 /* MSR_PR -> _PAGE_USER */ + rlwimi r3,r9,32-12,29,29 /* MSR_PR -> _PAGE_USER */ 112: #ifndef CONFIG_PTE_64BIT rlwimi r5,r4,12,20,29 /* insert top 10 bits of address */ @@ -94,7 +94,7 @@ _GLOBAL(hash_page) #else rlwimi r8,r4,23,20,28 /* compute pte address */ #endif - rlwinm r0,r3,6,24,24 /* _PAGE_RW access -> _PAGE_DIRTY */ + rlwinm r0,r3,32-3,24,24 /* _PAGE_RW access -> _PAGE_DIRTY */ ori r0,r0,_PAGE_ACCESSED|_PAGE_HASHPTE /* @@ -310,9 +310,11 @@ Hash_msk = (((1 << Hash_bits) - 1) * 64) _GLOBAL(create_hpte) /* Convert linux-style PTE (r5) to low word of PPC-style PTE (r8) */ + rlwinm r8,r5,32-9,30,30 /* _PAGE_RW -> PP msb */ rlwinm r0,r5,32-6,30,30 /* _PAGE_DIRTY -> PP msb */ - and r8,r5,r0 /* writable if _RW & _DIRTY */ - rlwimi r5,r5,1,30,30 /* _PAGE_USER -> PP msb */ + and r8,r8,r0 /* writable if _RW & _DIRTY */ + rlwimi r5,r5,32-1,30,30 /* _PAGE_USER -> PP msb */ + rlwimi r5,r5,32-2,31,31 /* _PAGE_USER -> PP lsb */ ori r8,r8,0xe04 /* clear out reserved bits */ andc r8,r5,r8 /* PP = user? (rw&dirty? 1: 3): 0 */ BEGIN_FTR_SECTION @@ -564,7 +566,7 @@ _GLOBAL(flush_hash_pages) 33: lwarx r8,0,r5 /* fetch the pte flags word */ andi. r0,r8,_PAGE_HASHPTE beq 8f /* done if HASHPTE is already clear */ - rlwinm r8,r8,0,~_PAGE_HASHPTE /* clear HASHPTE bit */ + rlwinm r8,r8,0,31,29 /* clear HASHPTE bit */ stwcx. r8,0,r5 /* update the pte */ bne- 33b |