diff options
| author | Damien Lespiau <damien.lespiau@intel.com> | 2013-07-12 16:24:40 +0100 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2013-07-12 17:33:21 +0200 |
| commit | 53b914084950e5766b40228c4e08706e28745fa5 (patch) | |
| tree | 70d1d2315bc66e6a177489cc6acb674779539465 | |
| parent | 08e2a7de8ec86054a1272e4fc9d15fa6c18d3b16 (diff) | |
drm/i915: Don't attempt to read an unitialized stack value
If intel_sdvo_get_value() fails here, val is unitialized and the cross
check will compare the pipe config multiplier with a bogus value.
Instead, only set encoder_pixel_multiplier when the sdvo command has
been successful. The cross check will compare the pipe config value with
0 otherwise.
v2: Do the cross check with the initial value of encoder_pixel_multiplier (0)
if the sdvo command fails (and thus keep the warning) (Daniel Vetter)
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
| -rw-r--r-- | drivers/gpu/drm/i915/intel_sdvo.c | 24 |
1 files changed, 13 insertions, 11 deletions
diff --git a/drivers/gpu/drm/i915/intel_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c index 8415d6a610d..798df114cfd 100644 --- a/drivers/gpu/drm/i915/intel_sdvo.c +++ b/drivers/gpu/drm/i915/intel_sdvo.c @@ -1357,17 +1357,19 @@ static void intel_sdvo_get_config(struct intel_encoder *encoder, } /* Cross check the port pixel multiplier with the sdvo encoder state. */ - intel_sdvo_get_value(intel_sdvo, SDVO_CMD_GET_CLOCK_RATE_MULT, &val, 1); - switch (val) { - case SDVO_CLOCK_RATE_MULT_1X: - encoder_pixel_multiplier = 1; - break; - case SDVO_CLOCK_RATE_MULT_2X: - encoder_pixel_multiplier = 2; - break; - case SDVO_CLOCK_RATE_MULT_4X: - encoder_pixel_multiplier = 4; - break; + if (intel_sdvo_get_value(intel_sdvo, SDVO_CMD_GET_CLOCK_RATE_MULT, + &val, 1)) { + switch (val) { + case SDVO_CLOCK_RATE_MULT_1X: + encoder_pixel_multiplier = 1; + break; + case SDVO_CLOCK_RATE_MULT_2X: + encoder_pixel_multiplier = 2; + break; + case SDVO_CLOCK_RATE_MULT_4X: + encoder_pixel_multiplier = 4; + break; + } } WARN(encoder_pixel_multiplier != pipe_config->pixel_multiplier, |