Quoting Sudeep Holla (2020-07-09 16:49:31)
Both cmp_u32 and cmp_u64 are comparing the pointers instead of the value at those pointers. This will result in incorrect/unsorted list. Fix it by deferencing the pointers before comparison.
Cc: Chris Wilson chris@chris-wilson.co.uk Cc: Mika Kuoppala mika.kuoppala@linux.intel.com Signed-off-by: Sudeep Holla sudeep.holla@arm.com
drivers/gpu/drm/i915/gt/selftest_rps.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
Hi,
I am not sure if I can put 2 fixes tags, but these are the ones affected.
Fixes: 4ba74e53ada3 ("drm/i915/selftests: Verify frequency scaling with RPS") Fixes: 8757797ff9c9 ("drm/i915/selftests: Repeat the rps clock frequency measurement")
Might as well tag the fixes, just in case anyone wants to use the tests.
I made similar mistake and after I fixed it, just looked if there are any similar bugs and found this.
Regards, Sudeep
diff --git a/drivers/gpu/drm/i915/gt/selftest_rps.c b/drivers/gpu/drm/i915/gt/selftest_rps.c index 5049c3dd08a6..c91981e75ebf 100644 --- a/drivers/gpu/drm/i915/gt/selftest_rps.c +++ b/drivers/gpu/drm/i915/gt/selftest_rps.c @@ -44,9 +44,9 @@ static int cmp_u64(const void *A, const void *B) { const u64 *a = A, *b = B;
if (a < b)
if (*a < *b) return -1;
else if (a > b)
else if (*a > *b) return 1;
Oh my golly gosh.
Thanks, thanks and thrice thanks. Reviewed-by: Chris Wilson chris@chris-wilson.co.uk
I better double check all my qsort-compare funcs for similar brianfarts. -Chris