{"id":"DEBIAN-CVE-2026-64100","details":"In the Linux kernel, the following vulnerability has been resolved:  drm/msm: Fix shrinker deadlock  With PROVE_LOCKING on an Snapdragon X1 and VM reclaim pressure, we see:     ======================================================    WARNING: possible circular locking dependency detected    7.0.0-debug+ #43 Tainted: G        W    ------------------------------------------------------    kswapd0/82 is trying to acquire lock:    ffff800080ec3870 (reservation_ww_class_acquire){+.+.}-{0:0}, at: msm_gem_shrinker_scan+0x17c/0x400 [msm]     but task is already holding lock:    ffffc31709b263b8 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x88/0x988     which lock already depends on the new lock.     the existing dependency chain (in reverse order) is:     -\u003e #2 (fs_reclaim){+.+.}-{0:0}:           __lock_acquire+0x4d0/0xad0           lock_acquire.part.0+0xc4/0x248           lock_acquire+0x8c/0x248           fs_reclaim_acquire+0xd0/0xf0           dma_resv_lockdep+0x224/0x348           do_one_initcall+0x84/0x5d0           do_initcalls+0x194/0x1d8           kernel_init_freeable+0x128/0x180           kernel_init+0x2c/0x160           ret_from_fork+0x10/0x20     -\u003e #1 (reservation_ww_class_mutex){+.+.}-{4:4}:           __lock_acquire+0x4d0/0xad0           lock_acquire.part.0+0xc4/0x248           lock_acquire+0x8c/0x248           dma_resv_lockdep+0x1a8/0x348           do_one_initcall+0x84/0x5d0           do_initcalls+0x194/0x1d8           kernel_init_freeable+0x128/0x180           kernel_init+0x2c/0x160           ret_from_fork+0x10/0x20     -\u003e #0 (reservation_ww_class_acquire){+.+.}-{0:0}:           check_prev_add+0x114/0x790           validate_chain+0x594/0x6f0           __lock_acquire+0x4d0/0xad0           lock_acquire.part.0+0xc4/0x248           lock_acquire+0x8c/0x248           drm_gem_lru_scan+0x1ac/0x440           msm_gem_shrinker_scan+0x17c/0x400 [msm]           do_shrink_slab+0x150/0x4a0           shrink_slab+0x144/0x460           shrink_one+0x9c/0x1b0           shrink_many+0x27c/0x5c0           shrink_node+0x344/0x550           balance_pgdat+0x2c0/0x988           kswapd+0x11c/0x318           kthread+0x10c/0x128           ret_from_fork+0x10/0x20     other info that might help us debug this:    Chain exists of:      reservation_ww_class_acquire --\u003e reservation_ww_class_mutex --\u003e fs_reclaim     Possible unsafe locking scenario:           CPU0                    CPU1           ----                    ----      lock(fs_reclaim);                                   lock(reservation_ww_class_mutex);                                   lock(fs_reclaim);      lock(reservation_ww_class_acquire);      *** DEADLOCK ***    1 lock held by kswapd0/82:     #0: ffffc31709b263b8 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x88/0x988     stack backtrace:    CPU: 4 UID: 0 PID: 82 Comm: kswapd0 Tainted: G        W           7.0.0-debug+ #43 PREEMPT(full)    Tainted: [W]=WARN    Hardware name: LENOVO 21BX0016US/21BX0016US, BIOS N3HET94W (1.66 ) 09/15/2025    Call trace:     show_stack+0x20/0x40 (C)     dump_stack_lvl+0x9c/0xd0     dump_stack+0x18/0x30     print_circular_bug+0x114/0x120     check_noncircular+0x178/0x198     check_prev_add+0x114/0x790     validate_chain+0x594/0x6f0     __lock_acquire+0x4d0/0xad0     lock_acquire.part.0+0xc4/0x248     lock_acquire+0x8c/0x248     drm_gem_lru_scan+0x1ac/0x440     msm_gem_shrinker_scan+0x17c/0x400 [msm]     do_shrink_slab+0x150/0x4a0     shrink_slab+0x144/0x460     shrink_one+0x9c/0x1b0     shrink_many+0x27c/0x5c0     shrink_node+0x344/0x550     balance_pgdat+0x2c0/0x988     kswapd+0x11c/0x318     kthread+0x10c/0x128     ret_from_fork+0x10/0x20  kswapd0 holding fs_reclaim calls the MSM shrinker, which calls dma_resv_lock. This in turn acquires fs_reclaim.  Fix this deadlock by using dma_resv_trylock() instead, dropping the subsequently unused passed wait-wound lock 'ticket'.  Patchwork: https://patchwork.freedesktop.org/patch/723564/ [rob: fixup compile errors, replace lockdep splat with somethin ---truncated---","modified":"2026-08-27T23:06:18.408392452Z","published":"2026-07-19T16:17:51.140Z","upstream":["CVE-2026-64100"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-64100"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.0.12-1"}]}],"versions":["6.12.100-1","6.12.101-1","6.12.105-1","6.12.38-1","6.12.41-1","6.12.43-1","6.12.43-1~bpo12+1","6.12.48-1","6.12.57-1","6.12.57-1~bpo12+1","6.12.63-1","6.12.63-1~bpo12+1","6.12.69-1","6.12.69-1~bpo12+1","6.12.73-1","6.12.73-1~bpo12+1","6.12.74-1","6.12.74-2","6.12.74-2~bpo12+1","6.12.85-1","6.12.85-1~bpo12+1","6.12.86-1","6.12.86-1~bpo12+1","6.12.88-1","6.12.88-1~bpo12+1","6.12.90-1","6.12.90-1~bpo12+1","6.12.90-2","6.12.90-2~bpo12+1","6.12.94-1","6.12.94-1~bpo12+1","6.12.95-1","6.12.95-1~bpo12+1","6.12.96-1","6.13.10-1~exp1","6.13.11-1~exp1","6.13.2-1~exp1","6.13.3-1~exp1","6.13.4-1~exp1","6.13.5-1~exp1","6.13.6-1~exp1","6.13.7-1~exp1","6.13.8-1~exp1","6.13.9-1~exp1","6.13~rc6-1~exp1","6.13~rc7-1~exp1","6.14.3-1~exp1","6.14.5-1~exp1","6.14.6-1~exp1","6.15-1~exp1","6.15.1-1~exp1","6.15.2-1~exp1","6.15.3-1~exp1","6.15.4-1~exp1","6.15.5-1~exp1","6.15.6-1~exp1","6.15~rc7-1~exp1","6.16-1~exp1","6.16.1-1~exp1","6.16.10-1","6.16.11-1","6.16.12-1","6.16.12-1~bpo13+1","6.16.12-2","6.16.3-1","6.16.3-1~bpo13+1","6.16.5-1","6.16.6-1","6.16.7-1","6.16.8-1","6.16.9-1","6.16~rc7-1~exp1","6.17.10-1","6.17.11-1","6.17.12-1","6.17.13-1","6.17.13-1~bpo13+1","6.17.2-1~exp1","6.17.5-1~exp1","6.17.6-1","6.17.7-1","6.17.7-2","6.17.8-1","6.17.8-1~bpo13+1","6.17.9-1","6.18.1-1~exp1","6.18.10-1","6.18.12-1","6.18.12-1~bpo13+1","6.18.13-1","6.18.14-1","6.18.15-1","6.18.15-1~bpo13+1","6.18.2-1~exp1","6.18.3-1","6.18.5-1","6.18.5-1~bpo13+1","6.18.8-1","6.18.9-1","6.18.9-1~bpo13+1","6.18~rc4-1~exp1","6.18~rc4-1~exp2","6.18~rc5-1~exp1","6.18~rc6-1~exp1","6.18~rc7-1~exp1","6.19-1~exp1","6.19.10-1","6.19.10-1~bpo13+1","6.19.11-1","6.19.11-1~bpo13+1","6.19.12-1","6.19.13-1","6.19.13-1~bpo13+1","6.19.14-1","6.19.14-1~bpo13+1","6.19.2-1~exp1","6.19.3-1~exp1","6.19.4-1~exp1","6.19.5-1~exp1","6.19.6-1","6.19.6-2","6.19.6-2~bpo13+1","6.19.8-1","6.19.8-1~bpo13+1","6.19~rc4-1~exp1","6.19~rc5-1~exp1","6.19~rc6-1~exp1","6.19~rc7-1~exp1","6.19~rc8-1~exp1","7.0-1~exp1","7.0.1-1~exp1","7.0.10-1","7.0.10-1~bpo13+1","7.0.3-1","7.0.4-1","7.0.4-1~bpo13+1","7.0.7-1","7.0.7-1~bpo13+1","7.0.9-1","7.0.9-1~bpo13+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-64100.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}