FKIE_CVE-2026-64100

Vulnerability from fkie_nvd - Published: 2026-07-19 16:17 - Updated: 2026-07-19 16:17
Severity
Summary
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: -> #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 -> #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 -> #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 --> reservation_ww_class_mutex --> 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---
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3392291fc509d8ad6e4ad90f15b0a193f721cbc9
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/928788566c79046f71a211fc32c115400be76402
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/942968260e61d4a5d7552b20814b6277f9c553df
Impacted products
Vendor Product Version
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{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/msm/msm_gem_shrinker.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "942968260e61d4a5d7552b20814b6277f9c553df",
              "status": "affected",
              "version": "fe4952b5f27cca5d143d3de249562d4cc984c1d6",
              "versionType": "git"
            },
            {
              "lessThan": "928788566c79046f71a211fc32c115400be76402",
              "status": "affected",
              "version": "fe4952b5f27cca5d143d3de249562d4cc984c1d6",
              "versionType": "git"
            },
            {
              "lessThan": "3392291fc509d8ad6e4ad90f15b0a193f721cbc9",
              "status": "affected",
              "version": "fe4952b5f27cca5d143d3de249562d4cc984c1d6",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/msm/msm_gem_shrinker.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.17"
            },
            {
              "lessThan": "6.17",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.34",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/msm: Fix shrinker deadlock\n\nWith PROVE_LOCKING on an Snapdragon X1 and VM reclaim pressure, we see:\n\n   ======================================================\n   WARNING: possible circular locking dependency detected\n   7.0.0-debug+ #43 Tainted: G        W\n   ------------------------------------------------------\n   kswapd0/82 is trying to acquire lock:\n   ffff800080ec3870 (reservation_ww_class_acquire){+.+.}-{0:0}, at: msm_gem_shrinker_scan+0x17c/0x400 [msm]\n\n   but task is already holding lock:\n   ffffc31709b263b8 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x88/0x988\n\n   which lock already depends on the new lock.\n\n   the existing dependency chain (in reverse order) is:\n\n   -\u003e #2 (fs_reclaim){+.+.}-{0:0}:\n          __lock_acquire+0x4d0/0xad0\n          lock_acquire.part.0+0xc4/0x248\n          lock_acquire+0x8c/0x248\n          fs_reclaim_acquire+0xd0/0xf0\n          dma_resv_lockdep+0x224/0x348\n          do_one_initcall+0x84/0x5d0\n          do_initcalls+0x194/0x1d8\n          kernel_init_freeable+0x128/0x180\n          kernel_init+0x2c/0x160\n          ret_from_fork+0x10/0x20\n\n   -\u003e #1 (reservation_ww_class_mutex){+.+.}-{4:4}:\n          __lock_acquire+0x4d0/0xad0\n          lock_acquire.part.0+0xc4/0x248\n          lock_acquire+0x8c/0x248\n          dma_resv_lockdep+0x1a8/0x348\n          do_one_initcall+0x84/0x5d0\n          do_initcalls+0x194/0x1d8\n          kernel_init_freeable+0x128/0x180\n          kernel_init+0x2c/0x160\n          ret_from_fork+0x10/0x20\n\n   -\u003e #0 (reservation_ww_class_acquire){+.+.}-{0:0}:\n          check_prev_add+0x114/0x790\n          validate_chain+0x594/0x6f0\n          __lock_acquire+0x4d0/0xad0\n          lock_acquire.part.0+0xc4/0x248\n          lock_acquire+0x8c/0x248\n          drm_gem_lru_scan+0x1ac/0x440\n          msm_gem_shrinker_scan+0x17c/0x400 [msm]\n          do_shrink_slab+0x150/0x4a0\n          shrink_slab+0x144/0x460\n          shrink_one+0x9c/0x1b0\n          shrink_many+0x27c/0x5c0\n          shrink_node+0x344/0x550\n          balance_pgdat+0x2c0/0x988\n          kswapd+0x11c/0x318\n          kthread+0x10c/0x128\n          ret_from_fork+0x10/0x20\n\n   other info that might help us debug this:\n   Chain exists of:\n     reservation_ww_class_acquire --\u003e reservation_ww_class_mutex --\u003e fs_reclaim\n    Possible unsafe locking scenario:\n          CPU0                    CPU1\n          ----                    ----\n     lock(fs_reclaim);\n                                  lock(reservation_ww_class_mutex);\n                                  lock(fs_reclaim);\n     lock(reservation_ww_class_acquire);\n\n    *** DEADLOCK ***\n   1 lock held by kswapd0/82:\n    #0: ffffc31709b263b8 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x88/0x988\n\n   stack backtrace:\n   CPU: 4 UID: 0 PID: 82 Comm: kswapd0 Tainted: G        W           7.0.0-debug+ #43 PREEMPT(full)\n   Tainted: [W]=WARN\n   Hardware name: LENOVO 21BX0016US/21BX0016US, BIOS N3HET94W (1.66 ) 09/15/2025\n   Call trace:\n    show_stack+0x20/0x40 (C)\n    dump_stack_lvl+0x9c/0xd0\n    dump_stack+0x18/0x30\n    print_circular_bug+0x114/0x120\n    check_noncircular+0x178/0x198\n    check_prev_add+0x114/0x790\n    validate_chain+0x594/0x6f0\n    __lock_acquire+0x4d0/0xad0\n    lock_acquire.part.0+0xc4/0x248\n    lock_acquire+0x8c/0x248\n    drm_gem_lru_scan+0x1ac/0x440\n    msm_gem_shrinker_scan+0x17c/0x400 [msm]\n    do_shrink_slab+0x150/0x4a0\n    shrink_slab+0x144/0x460\n    shrink_one+0x9c/0x1b0\n    shrink_many+0x27c/0x5c0\n    shrink_node+0x344/0x550\n    balance_pgdat+0x2c0/0x988\n    kswapd+0x11c/0x318\n    kthread+0x10c/0x128\n    ret_from_fork+0x10/0x20\n\nkswapd0 holding fs_reclaim calls the MSM shrinker, which calls\ndma_resv_lock. This in turn acquires fs_reclaim.\n\nFix this deadlock by using dma_resv_trylock() instead, dropping the\nsubsequently unused passed wait-wound lock \u0027ticket\u0027.\n\nPatchwork: https://patchwork.freedesktop.org/patch/723564/\n[rob: fixup compile errors, replace lockdep splat with somethin\n---truncated---"
    }
  ],
  "id": "CVE-2026-64100",
  "lastModified": "2026-07-19T16:17:51.140",
  "metrics": {},
  "published": "2026-07-19T16:17:51.140",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3392291fc509d8ad6e4ad90f15b0a193f721cbc9"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/928788566c79046f71a211fc32c115400be76402"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/942968260e61d4a5d7552b20814b6277f9c553df"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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