path: root/arch/s390/lib
diff options
authorMartin Schwidefsky <schwidefsky@de.ibm.com>2009-03-18 13:27:32 +0100
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2009-03-18 13:28:12 +0100
commit4fa81ed27781a12f6303b9263056635ae74e3e21 (patch)
treefab8df760ab6a01b9051c67b914c6e6b208607ba /arch/s390/lib
parentee568b25ee9e160b32d1aef73d8b2ee9c05d34db (diff)
[S390] __div64_31 broken for CONFIG_MARCH_G5
The implementation of __div64_31 for G5 machines is broken. The comments in __div64_31 are correct, only the code does not do what the comments say. The part "If the remainder has overflown subtract base and increase the quotient" is only partially realized, the base is subtracted correctly but the quotient is only increased if the dividend had the last bit set. Using the correct instruction fixes the problem. Cc: stable@kernel.org Reported-by: Frans Pop <elendil@planet.nl> Tested-by: Frans Pop <elendil@planet.nl> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/lib')
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/s390/lib/div64.c b/arch/s390/lib/div64.c
index a5f8300bf3e..d9e62c0b576 100644
--- a/arch/s390/lib/div64.c
+++ b/arch/s390/lib/div64.c
@@ -61,7 +61,7 @@ static uint32_t __div64_31(uint64_t *n, uint32_t base)
" clr %0,%3\n"
" jl 0f\n"
" slr %0,%3\n"
- " alr %1,%2\n"
+ " ahi %1,1\n"
: "+d" (reg2), "+d" (reg3), "=d" (tmp)
: "d" (base), "2" (1UL) : "cc" );