diff mbox

[v6,14/19] arm64:ilp32: add sys_ilp32.c and a separate table (in entry.S) to use it

Message ID 20151202103522.GB21461@yury-N73SV (mailing list archive)
State New, archived
Headers show

Commit Message

Yury Norov Dec. 2, 2015, 10:35 a.m. UTC 
On Wed, Dec 02, 2015 at 09:37:05AM +0100, Arnd Bergmann wrote:
> The 4*PAGE_SIZE on ARM is an architecture specific oddity, I believe
> to work around aliasing caches on ARMv6. As no other architecture does
> this, we're probably better off not duplicating it for aarch64-ilp32
> and just use sys_shmat as your v6 patch does.
> 	Arnd

If you feel ARMv6 fix for caches will come soon, just ignore it.
Otherwise, please pull it because compat_sys_shmat is broken now
for 64K pages.

Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
---
 arch/arm64/include/asm/shmparam.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Arnd Bergmann Dec. 2, 2015, 1:46 p.m. UTC | #1 
On Wednesday 02 December 2015 13:35:22 Yury Norov wrote:
> On Wed, Dec 02, 2015 at 09:37:05AM +0100, Arnd Bergmann wrote:
> > The 4*PAGE_SIZE on ARM is an architecture specific oddity, I believe
> > to work around aliasing caches on ARMv6. As no other architecture does
> > this, we're probably better off not duplicating it for aarch64-ilp32
> > and just use sys_shmat as your v6 patch does.
> >       Arnd
> 
> If you feel ARMv6 fix for caches will come soon, just ignore it.
> Otherwise, please pull it because compat_sys_shmat is broken now
> for 64K pages.
> 
> Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
> 

Sounds good. Will, do you want to take this for the arm64 tree.

Acked-by: Arnd Bergmann <arnd@arndb.de>
diff mbox

Patch

diff --git a/arch/arm64/include/asm/shmparam.h b/arch/arm64/include/asm/shmparam.h
index 4df608a..e368a55 100644
--- a/arch/arm64/include/asm/shmparam.h
+++ b/arch/arm64/include/asm/shmparam.h
@@ -21,7 +21,7 @@ 
  * alignment value. Since we don't have aliasing D-caches, the rest of
  * the time we can safely use PAGE_SIZE.
  */
-#define COMPAT_SHMLBA	0x4000
+#define COMPAT_SHMLBA	(4 * PAGE_SIZE)
 
 #include <asm-generic/shmparam.h>