From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
To: benh@kernel.crashing.org, paulus@samba.org, dwg@au1.ibm.com,
linux-mm@kvack.org
Cc: linuxppc-dev@lists.ozlabs.org,
"Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Subject: [PATCH -V7 07/18] powerpc: Don't truncate pgd_index wrongly
Date: Mon, 29 Apr 2013 01:07:28 +0530 [thread overview]
Message-ID: <1367177859-7893-8-git-send-email-aneesh.kumar@linux.vnet.ibm.com> (raw)
In-Reply-To: <1367177859-7893-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com>
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
With PGD_INDEX_SIZE set to 12 the existing macro doesn't work. Fix it to
use PTRS_PER_PGD
The idea originally was to have one more bit in the result of
pgd_index() than PGD_INDEX_SIZE, so that if one had an address
corresponding to the last PGD entry, and then incremented that address
by PGD_SIZE, and took pgd_index() of that, you wouldn't end up with
zero. The commit that introduced that dates back to 2002, and the
code that was sensitive to that edge case has long since been
refactored (several times), so there is no need for it these days.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/pgtable-ppc64.h | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/powerpc/include/asm/pgtable-ppc64.h b/arch/powerpc/include/asm/pgtable-ppc64.h
index 0182c20..e3d55f6f 100644
--- a/arch/powerpc/include/asm/pgtable-ppc64.h
+++ b/arch/powerpc/include/asm/pgtable-ppc64.h
@@ -167,8 +167,7 @@
* Find an entry in a page-table-directory. We combine the address region
* (the high order N bits) and the pgd portion of the address.
*/
-/* to avoid overflow in free_pgtables we don't use PTRS_PER_PGD here */
-#define pgd_index(address) (((address) >> (PGDIR_SHIFT)) & 0x1ff)
+#define pgd_index(address) (((address) >> (PGDIR_SHIFT)) & (PTRS_PER_PGD - 1))
#define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
--
1.8.1.2
next prev parent reply other threads:[~2013-04-28 19:37 UTC|newest]
Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-28 19:37 [PATCH -V7 00/18] THP support for PPC64 (Patchset 1) Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 01/18] mm/THP: HPAGE_SHIFT is not a #define on some arch Aneesh Kumar K.V
2013-04-30 2:21 ` David Gibson
2013-04-30 2:24 ` David Gibson
2013-04-30 3:42 ` Aneesh Kumar K.V
2013-04-30 5:01 ` David Gibson
2013-05-03 18:51 ` Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 02/18] mm/THP: Add pmd args to pgtable deposit and withdraw APIs Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 03/18] mm/THP: withdraw the pgtable after pmdp related operations Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 04/18] powerpc: Use signed formatting when printing error Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 05/18] powerpc: Save DAR and DSISR in pt_regs on MCE Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 06/18] powerpc: Don't hard code the size of pte page Aneesh Kumar K.V
2013-04-28 19:37 ` Aneesh Kumar K.V [this message]
2013-04-28 19:37 ` [PATCH -V7 08/18] powerpc: New hugepage directory format Aneesh Kumar K.V
2013-04-30 5:16 ` David Gibson
2013-04-28 19:37 ` [PATCH -V7 09/18] powerpc: Switch 16GB and 16MB explicit hugepages to a different page table format Aneesh Kumar K.V
2013-04-30 5:17 ` David Gibson
2013-06-06 22:42 ` Scott Wood
2013-06-07 3:55 ` Aneesh Kumar K.V
2013-06-07 19:17 ` Scott Wood
2013-06-08 16:57 ` Aneesh Kumar K.V
2013-06-11 20:53 ` Scott Wood
2013-06-11 22:50 ` Scott Wood
2013-06-12 6:30 ` Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 10/18] powerpc: Reduce the PTE_INDEX_SIZE Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 11/18] powerpc: Move the pte free routines from common header Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 12/18] powerpc: Reduce PTE table memory wastage Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 13/18] powerpc: Use encode avpn where we need only avpn values Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 14/18] powerpc: Decode the pte-lp-encoding bits correctly Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 15/18] powerpc: Fix hpte_decode to use the correct decoding for page sizes Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 16/18] powerpc: print both base and actual page size on hash failure Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 17/18] powerpc: Print page size info during boot Aneesh Kumar K.V
2013-04-28 19:37 ` [PATCH -V7 18/18] powerpc: Update tlbie/tlbiel as per ISA doc Aneesh Kumar K.V
2013-04-30 6:15 ` David Gibson
2013-04-30 17:21 ` Aneesh Kumar K.V
2013-05-01 5:26 ` David Gibson
2013-05-01 7:47 ` Aneesh Kumar K.V
2013-05-01 7:52 ` Simon Jeons
2013-05-01 11:36 ` David Gibson
2013-05-02 5:23 ` David Gibson
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