[PATCH] powerpc/perf/hv-24x7: Fix incorrect comparison in memord

Michael Ellerman mpe at ellerman.id.au
Mon Oct 9 21:52:44 AEDT 2017

In the hv-24x7 code there is a function memord() which tries to
implement a sort function return -1, 0, 1. However one of the
conditions is incorrect, such that it can never be true, because we
will have already returned.

I don't believe there is a bug in practice though, because the
comparisons are an optimisation prior to calling memcmp().

Fix it by swapping the second comparision, so it can be true.

Reported-by: David Binderman <dcb314 at hotmail.com>
Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
 arch/powerpc/perf/hv-24x7.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/perf/hv-24x7.c b/arch/powerpc/perf/hv-24x7.c
index 9c88b82f6229..72238eedc360 100644
--- a/arch/powerpc/perf/hv-24x7.c
+++ b/arch/powerpc/perf/hv-24x7.c
@@ -540,7 +540,7 @@ static int memord(const void *d1, size_t s1, const void *d2, size_t s2)
 	if (s1 < s2)
 		return 1;
-	if (s2 > s1)
+	if (s1 > s2)
 		return -1;
 	return memcmp(d1, d2, s1);

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