syzbot


WARNING in __page_cache_release

Status: upstream: reported on 2026/04/30 06:59
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+ba145f7f5f26bf2a11a2@syzkaller.appspotmail.com
First crash: 25d, last: 25d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
15664fcc-9e07-4bbd-beec-b7e1eb6a63eb assessment-security 💥 WARNING in __page_cache_release 2026/05/14 11:14 2026/05/14 11:14 2026/05/14 11:16 6ccb967e465e832a7bfd7a116ad00d52a0923a5d failed to run ["make" "KERNELVERSION=syzkaller" "KERNELRELEASE=syzkaller" "LOCALVERSION=-syzkaller" "-j" "32" "ARCH=x86_64" "CC=ccache clang" "LD=ld.lld" "O=/app/workdir/cache/build/138ebfc48a519a8e871102614e5b9368fb1156b1" "-s" "bzImage" "compile_commands.json"]: exit status 2 Root cause: error: unable to open output file 'kernel/printk/printk.o': 'No such file or directory' error: unable to open output file 'security/integrity/ima/ima_fs.o': 'No such file or directory' * * Restart config... * * * General architecture-dependent options * SMT (Hyperthreading) scheduler support (SCHED_SMT) [Y/?] y Cluster scheduler support (SCHED_CLUSTER) [Y/n/?] y Multi-Core Cache (MC) scheduler support (SCHED_MC) [Y/n/?] y Kprobes (KPROBES) [N/y/?] n Optimize very unlikely/likely branches (JUMP_LABEL) [Y/n/?] y Static key selftest (STATIC_KEYS_SELFTEST) [N/y/?] n Static call selftest (STATIC_CALL_SELFTEST) [N/y/?] n Enable seccomp to safely execute untrusted bytecode (SECCOMP) [Y/n/?] y Show seccomp filter cache status in /proc/pid/seccomp_cache (SECCOMP_CACHE_DEBUG) [N/y/?] n Stack Protector buffer overflow detection (STACKPROTECTOR) [Y/n/?] y Strong Stack Protector (STACKPROTECTOR_STRONG) [Y/n/?] y Link Time Optimization (LTO) > 1. None (LTO_NONE) choice[1]: 1 Enable Clang's AutoFDO build (EXPERIMENTAL) (AUTOFDO_CLANG) [N/y/?] (NEW) Error in reading or end of file. Enable Clang's Propeller build (PROPELLER_CLANG) [N/y/?] (NEW) Error in reading or end of file. Use Kernel Control Flow Integrity (kCFI) (CFI) [N/y/?] (NEW) Error in reading or end of file. Number of bits to use for ASLR of mmap base address (ARCH_MMAP_RND_BITS) [28] 28 Number of bits to use for ASLR of mmap base address for compatible applications (ARCH_MMAP_RND_COMPAT_BITS) [8] 8 MMU page size > 1. 4KiB pages (PAGE_SIZE_4KB) choice[1]: 1 Provide system calls for 32-bit time_t (COMPAT_32BIT_TIME) [Y/n/?] y Use a virtually-mapped stack (VMAP_STACK) [Y/n/?] y Support for randomizing kernel stack offset on syscall entry (RANDOMIZE_KSTACK_OFFSET) [Y/n/?] y Default state of kernel stack offset randomization (RANDOMIZE_KSTACK_OFFSET_DEFAULT) [N/y/?] n Locking event counts collection (LOCK_EVENT_COUNTS) [N/y/?] n * * Memory initialization * Initialize kernel stack variables at function entry 1. no automatic stack variable initialization (weakest) (INIT_STACK_NONE) 2. pattern-init everything (strongest) (INIT_STACK_ALL_PATTERN) > 3. zero-init everything (strongest and safest) (INIT_STACK_ALL_ZERO) choice[1-3?]: 3 Poison kernel stack before returning from syscalls (KSTACK_ERASE) [N/y/?] (NEW) Error in reading or end of file. Enable heap memory zeroing on allocation by default (INIT_ON_ALLOC_DEFAULT_ON) [Y/n/?] y Enable heap memory zeroing on free by default (INIT_ON_FREE_DEFAULT_ON) [N/y/?] n Enable register zeroing on function exit (ZERO_CALL_USED_REGS) [N/y/?] n * * Kernel hardening options * Randomize layout of sensitive kernel structures > 1. Disable structure layout randomization (RANDSTRUCT_NONE) 2. Fully randomize structure layout (RANDSTRUCT_FULL) (NEW) choice[1-2?]: Error in reading or end of file. /app/workdir/cache/src/316e237849c78635c7c5ae4b5398d0fa5c963d95/lib/maple_tree.c:3514:20: warning: stack frame size (2424) exceeds limit (2048) in 'mas_wr_store_entry' [-Wframe-larger-than] 3514 | static inline void mas_wr_store_entry(struct ma_wr_state *wr_mas) | ^ 1 warning generated. /app/workdir/cache/src/316e237849c78635c7c5ae4b5398d0fa5c963d95/security/apparmor/apparmorfs.c:177:28: warning: unused function 'get_loaddata_common_ref' [-Wunused-function] 177 | static struct aa_loaddata *get_loaddata_common_ref(struct aa_common_ref *ref) | ^~~~~~~~~~~~~~~~~~~~~~~ 1 warning generated. /app/workdir/cache/src/316e237849c78635c7c5ae4b5398d0fa5c963d95/sound/usb/mixer_s1810c.c:634:5: warning: stack frame size (2360) exceeds limit (2048) in 'snd_sc1810_init_mixer' [-Wframe-larger-than] 634 | int snd_sc1810_init_mixer(struct usb_mixer_interface *mixer) | ^ 1 warning generated. /app/workdir
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [mm?] WARNING in __page_cache_release 0 (1) 2026/04/30 06:59

Sample crash report:
------------[ cut here ]------------
debug_locks && !(rcu_read_lock_held() || lock_is_held(&(&cgroup_mutex)->dep_map))
WARNING: ./include/linux/memcontrol.h:380 at obj_cgroup_memcg include/linux/memcontrol.h:380 [inline], CPU#1: dhcpcd-run-hook/5685
WARNING: ./include/linux/memcontrol.h:380 at folio_memcg include/linux/memcontrol.h:434 [inline], CPU#1: dhcpcd-run-hook/5685
WARNING: ./include/linux/memcontrol.h:380 at folio_matches_lruvec include/linux/memcontrol.h:1501 [inline], CPU#1: dhcpcd-run-hook/5685
WARNING: ./include/linux/memcontrol.h:380 at folio_lruvec_relock_irqsave include/linux/memcontrol.h:1523 [inline], CPU#1: dhcpcd-run-hook/5685
WARNING: ./include/linux/memcontrol.h:380 at __page_cache_release.part.0+0x1149/0x1440 mm/swap.c:77, CPU#1: dhcpcd-run-hook/5685
Modules linked in:
CPU: 1 UID: 0 PID: 5685 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:obj_cgroup_memcg include/linux/memcontrol.h:380 [inline]
RIP: 0010:folio_memcg include/linux/memcontrol.h:434 [inline]
RIP: 0010:folio_matches_lruvec include/linux/memcontrol.h:1501 [inline]
RIP: 0010:folio_lruvec_relock_irqsave include/linux/memcontrol.h:1523 [inline]
RIP: 0010:__page_cache_release.part.0+0x1149/0x1440 mm/swap.c:77
Code: 00 0f 85 b2 02 00 00 89 c6 31 ff 89 44 24 08 49 8b 2c 24 e8 29 a8 c0 ff 8b 44 24 08 85 c0 0f 85 34 fa ff ff e8 68 ad c0 ff 90 <0f> 0b 90 e9 26 fa ff ff e8 5a ad c0 ff 48 c7 c6 c0 a0 bd 8b 48 89
RSP: 0018:ffffc900045af6f8 EFLAGS: 00010093
RAX: 0000000000000000 RBX: ffffea00014fe100 RCX: ffffffff82472de7
RDX: ffff888027be4a00 RSI: ffffffff82472df8 RDI: ffff888027be4a00
RBP: ffff8880404a0048 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffc900045af7a8
R13: ffffc900045af7c8 R14: ffff88801b8ffe00 R15: 00000000000000ff
FS:  0000000000000000(0000) GS:ffff888097280000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1d72d36368 CR3: 0000000052fd2000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 __page_cache_release mm/swap.c:1009 [inline]
 folios_put_refs+0x780/0xa90 mm/swap.c:993
 free_pages_and_swap_cache+0x22d/0x3b0 mm/swap_state.c:401
 __tlb_batch_free_encoded_pages+0xe9/0x280 mm/mmu_gather.c:138
 tlb_batch_pages_flush mm/mmu_gather.c:151 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:417 [inline]
 tlb_flush_mmu mm/mmu_gather.c:424 [inline]
 tlb_finish_mmu+0x1b0/0x810 mm/mmu_gather.c:549
 exit_mmap+0x454/0xa10 mm/mmap.c:1313
 __mmput+0x12a/0x410 kernel/fork.c:1178
 mmput+0x67/0x80 kernel/fork.c:1201
 exit_mm kernel/exit.c:581 [inline]
 do_exit+0x833/0x2a60 kernel/exit.c:963
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1117
 __do_sys_exit_group kernel/exit.c:1128 [inline]
 __se_sys_exit_group kernel/exit.c:1126 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1126
 x64_sys_call+0x102c/0x1530 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1d72b666c5
Code: Unable to access opcode bytes at 0x7f1d72b6669b.
RSP: 002b:00007ffd91878108 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007ffd91878404 RCX: 00007f1d72b666c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000
RBP: 0000000000000003 R08: 00007ffd91878200 R09: 0000000000000002
R10: 00007f1d72c0cfe0 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffd91878440 R14: 00007f1d72d76000 R15: 000056441d2c7d98
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/26 06:42 upstream 897d54018cc9 9c2d0995 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __page_cache_release
* Struck through repros no longer work on HEAD.