Commit d2e59d0f authored by Krunoslav Kovac's avatar Krunoslav Kovac Committed by Alex Deucher

drm/amd/display: fix pow() crashing when given base 0

[Why&How]
pow(a,x) is implemented as exp(x*log(a)). log(0) will crash.
So return 0^x = 0, unless x=0, convention seems to be 0^0 = 1.

Cc: stable@vger.kernel.org
Signed-off-by: default avatarKrunoslav Kovac <Krunoslav.Kovac@amd.com>
Reviewed-by: default avatarAnthony Koo <Anthony.Koo@amd.com>
Acked-by: default avatarRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent db0473f6
...@@ -431,6 +431,9 @@ struct fixed31_32 dc_fixpt_log(struct fixed31_32 arg); ...@@ -431,6 +431,9 @@ struct fixed31_32 dc_fixpt_log(struct fixed31_32 arg);
*/ */
static inline struct fixed31_32 dc_fixpt_pow(struct fixed31_32 arg1, struct fixed31_32 arg2) static inline struct fixed31_32 dc_fixpt_pow(struct fixed31_32 arg1, struct fixed31_32 arg2)
{ {
if (arg1.value == 0)
return arg2.value == 0 ? dc_fixpt_one : dc_fixpt_zero;
return dc_fixpt_exp( return dc_fixpt_exp(
dc_fixpt_mul( dc_fixpt_mul(
dc_fixpt_log(arg1), dc_fixpt_log(arg1),
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment