The acquire ctx will typically be declared on the stack, which means we could have garbage values for any uninitialized field. In this case, it was triggering WARN_ON()s because 'contended' had garbage value.
Go ahead and use memset() to be more future-proof.
v2: now with extra brown paper bag
Reported-by: Ville Syrjälä ville.syrjala@linux.intel.com Signed-off-by: Rob Clark robdclark@gmail.com --- drivers/gpu/drm/drm_modeset_lock.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/gpu/drm/drm_modeset_lock.c b/drivers/gpu/drm/drm_modeset_lock.c index 7c2497d..0dc57d5 100644 --- a/drivers/gpu/drm/drm_modeset_lock.c +++ b/drivers/gpu/drm/drm_modeset_lock.c @@ -64,6 +64,7 @@ void drm_modeset_acquire_init(struct drm_modeset_acquire_ctx *ctx, uint32_t flags) { + memset(ctx, 0, sizeof(*ctx)); ww_acquire_init(&ctx->ww_ctx, &crtc_ww_class); INIT_LIST_HEAD(&ctx->locked); }
On Sat, Jun 07, 2014 at 10:55:39AM -0400, Rob Clark wrote:
The acquire ctx will typically be declared on the stack, which means we could have garbage values for any uninitialized field. In this case, it was triggering WARN_ON()s because 'contended' had garbage value.
Go ahead and use memset() to be more future-proof.
v2: now with extra brown paper bag
Reported-by: Ville Syrjälä ville.syrjala@linux.intel.com Signed-off-by: Rob Clark robdclark@gmail.com
I thought I already gave these. Well here they are again: Reviewed-by: Ville Syrjälä ville.syrjala@linux.intel.com Tested-by: Ville Syrjälä ville.syrjala@linux.intel.com
drivers/gpu/drm/drm_modeset_lock.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/gpu/drm/drm_modeset_lock.c b/drivers/gpu/drm/drm_modeset_lock.c index 7c2497d..0dc57d5 100644 --- a/drivers/gpu/drm/drm_modeset_lock.c +++ b/drivers/gpu/drm/drm_modeset_lock.c @@ -64,6 +64,7 @@ void drm_modeset_acquire_init(struct drm_modeset_acquire_ctx *ctx, uint32_t flags) {
- memset(ctx, 0, sizeof(*ctx)); ww_acquire_init(&ctx->ww_ctx, &crtc_ww_class); INIT_LIST_HEAD(&ctx->locked);
}
1.9.3
On Wed, 18 Jun 2014, Ville Syrjälä ville.syrjala@linux.intel.com wrote:
On Sat, Jun 07, 2014 at 10:55:39AM -0400, Rob Clark wrote:
The acquire ctx will typically be declared on the stack, which means we could have garbage values for any uninitialized field. In this case, it was triggering WARN_ON()s because 'contended' had garbage value.
Go ahead and use memset() to be more future-proof.
v2: now with extra brown paper bag
Reported-by: Ville Syrjälä ville.syrjala@linux.intel.com Signed-off-by: Rob Clark robdclark@gmail.com
I thought I already gave these. Well here they are again: Reviewed-by: Ville Syrjälä ville.syrjala@linux.intel.com Tested-by: Ville Syrjälä ville.syrjala@linux.intel.com
https://bugzilla.kernel.org/show_bug.cgi?id=78401
drivers/gpu/drm/drm_modeset_lock.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/gpu/drm/drm_modeset_lock.c b/drivers/gpu/drm/drm_modeset_lock.c index 7c2497d..0dc57d5 100644 --- a/drivers/gpu/drm/drm_modeset_lock.c +++ b/drivers/gpu/drm/drm_modeset_lock.c @@ -64,6 +64,7 @@ void drm_modeset_acquire_init(struct drm_modeset_acquire_ctx *ctx, uint32_t flags) {
- memset(ctx, 0, sizeof(*ctx)); ww_acquire_init(&ctx->ww_ctx, &crtc_ww_class); INIT_LIST_HEAD(&ctx->locked);
}
1.9.3
-- Ville Syrjälä Intel OTC _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/dri-devel
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