In the Linux kernel, the following vulnerability has been resolved: drm/gma500: Fix BUG: sleeping function called from invalid context errors gma_crtc_page_flip() was holding the event_lock spinlock while calling crtc_funcs->mode_set_base() which takes ww_mutex. The only reason to hold event_lock is to clear gma_crtc->page_flip_event on mode_set_base() errors. Instead unlock it after setting gma_crtc->page_flip_event and on errors re-take the lock and clear gma_crtc->page_flip_event it it is still set. This fixes the following WARN/stacktrace: [ 512.122953] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:870 [ 512.123004] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1253, name: gnome-shell [ 512.123031] preempt_count: 1, expected: 0 [ 512.12