| From d9813c3681a36774b254c0cdc9cce53c9e22c756 Mon Sep 17 00:00:00 2001 |
| From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> |
| Date: Tue, 1 Oct 2013 16:54:05 +1000 |
| Subject: powerpc: Fix parameter clobber in csum_partial_copy_generic() |
| |
| From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> |
| |
| commit d9813c3681a36774b254c0cdc9cce53c9e22c756 upstream. |
| |
| The csum_partial_copy_generic() uses register r7 to adjust the remaining |
| bytes to process. Unfortunately, r7 also holds a parameter, namely the |
| address of the flag to set in case of access exceptions while reading |
| the source buffer. Lacking a quantum implementation of PowerPC, this |
| commit instead uses register r9 to do the adjusting, leaving r7's |
| pointer uncorrupted. |
| |
| Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> |
| Signed-off-by: Anton Blanchard <anton@samba.org> |
| Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| arch/powerpc/lib/checksum_64.S | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| --- a/arch/powerpc/lib/checksum_64.S |
| +++ b/arch/powerpc/lib/checksum_64.S |
| @@ -269,8 +269,8 @@ _GLOBAL(csum_partial_copy_generic) |
| rldicl. r6,r3,64-1,64-2 /* r6 = (r3 & 0x3) >> 1 */ |
| beq .Lcopy_aligned |
| |
| - li r7,4 |
| - sub r6,r7,r6 |
| + li r9,4 |
| + sub r6,r9,r6 |
| mtctr r6 |
| |
| 1: |