On Tue, Oct 31, 2017 at 11:55:35AM +0000, Chris Wilson wrote: > To acquire all modeset locks requires a ww_ctx to be allocated. As this > is the legacy path and the allocation small, to reduce the changes > required (and complex untested error handling) to the legacy drivers, we > simply assume that the allocation succeeds. At present, it relies on the > too-small-to-fail rule, but syzbot found that by injecting a failure > here we would hit the WARN. Document that this allocation must succeed > with __GFP_NOFAIL. > > Reported-by: syzbot (syzkaller) > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > --- > Resent to the right list! > --- > drivers/gpu/drm/drm_modeset_lock.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_modeset_lock.c b/drivers/gpu/drm/drm_modeset_lock.c > index e123497da0ca..963e23db0fe7 100644 > --- a/drivers/gpu/drm/drm_modeset_lock.c > +++ b/drivers/gpu/drm/drm_modeset_lock.c > @@ -93,7 +93,7 @@ void drm_modeset_lock_all(struct drm_device *dev) > struct drm_modeset_acquire_ctx *ctx; > int ret; > > - ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); > + ctx = kzalloc(sizeof(*ctx), GFP_KERNEL | __GFP_NOFAIL); > if (WARN_ON(!ctx)) > return; > > -- > 2.15.0.rc2 > > _______________________________________________ > dri-devel mailing list > dri-devel@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Ville Syrjälä Intel OTC _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel