diff options
| author | Krunoslav Kovac <Krunoslav.Kovac@amd.com> | 2020-08-06 17:54:47 -0400 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2020-08-18 18:01:21 -0400 |
| commit | d2e59d0ff4c44d1f6f8ed884a5bea7d1bb7fd98c (patch) | |
| tree | 848e6e3b5e1c708c555ad9aca80db30034f760db /drivers/gpu/drm/amd | |
| parent | db0473f62438e075b6832fd1490fd06d03c59372 (diff) | |
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: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Diffstat (limited to 'drivers/gpu/drm/amd')
| -rw-r--r-- | drivers/gpu/drm/amd/display/include/fixed31_32.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/display/include/fixed31_32.h b/drivers/gpu/drm/amd/display/include/fixed31_32.h index 89ef9f6860e5..16df2a485dd0 100644 --- a/drivers/gpu/drm/amd/display/include/fixed31_32.h +++ b/drivers/gpu/drm/amd/display/include/fixed31_32.h @@ -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) { + if (arg1.value == 0) + return arg2.value == 0 ? dc_fixpt_one : dc_fixpt_zero; + return dc_fixpt_exp( dc_fixpt_mul( dc_fixpt_log(arg1), |