From 72480ef863740c3dc301b0803c9ed6d10716aa11 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Fri, 20 May 2005 16:50:55 +1000 Subject: [PATCH] [PATCH] ppc32: Fix __copy_tofrom_user return value Recently the __copy_tofrom_user routine was modified to avoid doing prefetches past the end of the source array. However, in doing so we introduced a bug in that it now returns the wrong value for the number of bytes not copied when a fault is encountered. This fixes it to return the correct number. Signed-off-by: Paul Mackerras Signed-off-by: Linus Torvalds --- arch/ppc/lib/string.S | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/ppc/lib/string.S b/arch/ppc/lib/string.S index 8d08a2eb225e..36c9b97fd92a 100644 --- a/arch/ppc/lib/string.S +++ b/arch/ppc/lib/string.S @@ -446,6 +446,7 @@ _GLOBAL(__copy_tofrom_user) #ifdef CONFIG_8xx /* Don't use prefetch on 8xx */ mtctr r0 + li r0,0 53: COPY_16_BYTES_WITHEX(0) bdnz 53b @@ -564,7 +565,9 @@ _GLOBAL(__copy_tofrom_user) /* or write fault in cacheline loop */ 105: li r9,1 92: li r3,LG_CACHELINE_BYTES - b 99f + mfctr r8 + add r0,r0,r8 + b 106f /* read fault in final word loop */ 108: li r9,0 b 93f @@ -585,7 +588,7 @@ _GLOBAL(__copy_tofrom_user) * r5 + (ctr << r3), and r9 is 0 for read or 1 for write. */ 99: mfctr r0 - slw r3,r0,r3 +106: slw r3,r0,r3 add. r3,r3,r5 beq 120f /* shouldn't happen */ cmpwi 0,r9,0 -- 2.20.1