From: Paul E. McKenney Date: Tue, 1 Oct 2013 06:54:05 +0000 (+1000) Subject: powerpc: Fix parameter clobber in csum_partial_copy_generic() X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=d9813c3681a36774b254c0cdc9cce53c9e22c756;p=openwrt%2Fstaging%2Fblogic.git powerpc: Fix parameter clobber in csum_partial_copy_generic() 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 Signed-off-by: Anton Blanchard Cc: stable@vger.kernel.org Signed-off-by: Benjamin Herrenschmidt --- diff --git a/arch/powerpc/lib/checksum_64.S b/arch/powerpc/lib/checksum_64.S index 167f72555d60..609665aede75 100644 --- 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: