CVE-2025-21911

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> drm/imagination: avoid deadlock on fence release<br /> <br /> Do scheduler queue fence release processing on a workqueue, rather<br /> than in the release function itself.<br /> <br /> Fixes deadlock issues such as the following:<br /> <br /> [ 607.400437] ============================================<br /> [ 607.405755] WARNING: possible recursive locking detected<br /> [ 607.415500] --------------------------------------------<br /> [ 607.420817] weston:zfq0/24149 is trying to acquire lock:<br /> [ 607.426131] ffff000017d041a0 (reservation_ww_class_mutex){+.+.}-{3:3}, at: pvr_gem_object_vunmap+0x40/0xc0 [powervr]<br /> [ 607.436728]<br /> but task is already holding lock:<br /> [ 607.442554] ffff000017d105a0 (reservation_ww_class_mutex){+.+.}-{3:3}, at: dma_buf_ioctl+0x250/0x554<br /> [ 607.451727]<br /> other info that might help us debug this:<br /> [ 607.458245] Possible unsafe locking scenario:<br /> <br /> [ 607.464155] CPU0<br /> [ 607.466601] ----<br /> [ 607.469044] lock(reservation_ww_class_mutex);<br /> [ 607.473584] lock(reservation_ww_class_mutex);<br /> [ 607.478114]<br /> *** DEADLOCK ***