syzbot


INFO: task hung in txBegin

Status: upstream: reported C repro on 2024/06/25 15:36
Subsystems: jfs
[Documentation on labels]
Reported-by: syzbot+eda89a33c5856f66f823@syzkaller.appspotmail.com
First crash: 836d, last: 12h22m
Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: BUG: unable to handle kernel NULL pointer dereference in write_special_inodes (log)
Repro: C syz .config
  
Fix bisection: the issue occurs on the latest tested release (bisect log)
  
✨ AI Jobs (4)
ID Workflow Result Correct Ext Bug ID Bug Created Started Finished Revision Error
ad8fba7c-c043-4b52-86d8-6f361354666a assessment-security 💥 INFO: task hung in txBegin 2026/06/09 22:37 2026/06/09 22:37 2026/06/09 23:00 c36c07f6c1f2230a36374cbd22235f635e8f9284 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/568a4c43274506e32b707175eed8752a441974b3" "-s" "bzImage" "compile_commands.json"]: exit status 2 Root cause: drivers/nvme/target/fc.c:151:2: warning: 'counted_by' should not be applied to an array with element of unknown size because 'struct nvmet_fc_fcp_iod' is a struct type with a flexible array member. This will be an error in a future compiler version [-Wbounds-safety-counted-by-elt-type-unknown-size] ld.lld: error: undefined symbol: wcslen * * Restart config... * * * General architecture-dependent options * 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 Link Time Optimization (LTO) > 1. None (LTO_NONE) choice[1]: 1 Use Clang's Control Flow Integrity (CFI) (CFI_CLANG) [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 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/?] (NEW) Error in reading or end of file. * * 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. * * Compile-time checks and compiler options * Debug information 1. Disable debug information (DEBUG_INFO_NONE) 2. Rely on the toolchain's implicit default DWARF version (DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT) > 3. Generate DWARF Version 4 debuginfo (DEBUG_INFO_DWARF4) 4. Generate DWARF Version 5 debuginfo (DEBUG_INFO_DWARF5) choice[1-4?]: 3 Reduce debugging information (DEBUG_INFO_REDUCED) [N/y/?] n Compressed Debug information > 1. Don't compress debug information (DEBUG_INFO_COMPRESSED_NONE) 2. Compress debugging information with zlib (DEBUG_INFO_COMPRESSED_ZLIB) 3. Compress debugging information with zstd (DEBUG_INFO_COMPRESSED_ZSTD) (NEW) choice[1-3?]: Error in reading or end of file. Produce split debuginfo in .dwo files (DEBUG_INFO_SPLIT) [N/y/?] n Generate BTF type information (DEBUG_INFO_BTF) [N/y/?] n Provide GDB scripts for kernel debugging (GDB_SCRIPTS) [N/y/?] n Warn for stack frames larger than (FRAME_WARN) [2048] 2048 Strip assembler-generated symbols during link (STRIP_ASM_SYMS) [N/y/?] n Install uapi headers to usr/include (HEADERS_INSTALL) [N/y/?] n Make section mismatch errors non-fatal (SECTION_MISMATCH_WARN_ONLY) [Y/n/?] y Force all function address 64B aligned (DEBUG_FORCE_FUNCTION_ALIGN_64B) [N/y/?] n Generate vmlinux.map file when linking (VMLINUX_MAP) [N/y/?] n Force weak per-cpu definitions (DEBUG_FORCE_WEAK_PER_CPU) [N/y/?] n In file
a36491ca-0add-47d3-a39a-9e5bbf13427e assessment-security 💥 INFO: task hung in txBegin 2026/06/03 00:19 2026/06/03 00:19 2026/06/03 00:44 62fe15281f5011cd203d8845b8767b10e7443aa5 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/568a4c43274506e32b707175eed8752a441974b3" "-s" "bzImage" "compile_commands.json"]: exit status 2 Root cause: drivers/nvme/target/fc.c:151:2: warning: 'counted_by' should not be applied to an array with element of unknown size because 'struct nvmet_fc_fcp_iod' is a struct type with a flexible array member. This will be an error in a future compiler version [-Wbounds-safety-counted-by-elt-type-unknown-size] ld.lld: error: undefined symbol: wcslen * * Restart config... * * * General architecture-dependent options * 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 Link Time Optimization (LTO) > 1. None (LTO_NONE) choice[1]: 1 Use Clang's Control Flow Integrity (CFI) (CFI_CLANG) [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 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/?] (NEW) Error in reading or end of file. * * 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. * * Compile-time checks and compiler options * Debug information 1. Disable debug information (DEBUG_INFO_NONE) 2. Rely on the toolchain's implicit default DWARF version (DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT) > 3. Generate DWARF Version 4 debuginfo (DEBUG_INFO_DWARF4) 4. Generate DWARF Version 5 debuginfo (DEBUG_INFO_DWARF5) choice[1-4?]: 3 Reduce debugging information (DEBUG_INFO_REDUCED) [N/y/?] n Compressed Debug information > 1. Don't compress debug information (DEBUG_INFO_COMPRESSED_NONE) 2. Compress debugging information with zlib (DEBUG_INFO_COMPRESSED_ZLIB) 3. Compress debugging information with zstd (DEBUG_INFO_COMPRESSED_ZSTD) (NEW) choice[1-3?]: Error in reading or end of file. Produce split debuginfo in .dwo files (DEBUG_INFO_SPLIT) [N/y/?] n Generate BTF type information (DEBUG_INFO_BTF) [N/y/?] n Provide GDB scripts for kernel debugging (GDB_SCRIPTS) [N/y/?] n Warn for stack frames larger than (FRAME_WARN) [2048] 2048 Strip assembler-generated symbols during link (STRIP_ASM_SYMS) [N/y/?] n Install uapi headers to usr/include (HEADERS_INSTALL) [N/y/?] n Make section mismatch errors non-fatal (SECTION_MISMATCH_WARN_ONLY) [Y/n/?] y Force all function address 64B aligned (DEBUG_FORCE_FUNCTION_ALIGN_64B) [N/y/?] n Generate vmlinux.map file when linking (VMLINUX_MAP) [N/y/?] n Force weak per-cpu definitions (DEBUG_FORCE_WEAK_PER_CPU) [N/y/?] n In file
765cbe0b-7a93-4c5d-bd92-29356cab2d31 assessment-security 💥 INFO: task hung in txBegin 2026/05/31 23:44 2026/05/31 23:44 2026/06/01 00:06 6b4a844333e83556da95d61d7f207e7ef5cd4bc6 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/568a4c43274506e32b707175eed8752a441974b3" "-s" "bzImage" "compile_commands.json"]: exit status 2 Root cause: drivers/nvme/target/fc.c:151:2: warning: 'counted_by' should not be applied to an array with element of unknown size because 'struct nvmet_fc_fcp_iod' is a struct type with a flexible array member. This will be an error in a future compiler version [-Wbounds-safety-counted-by-elt-type-unknown-size] ld.lld: error: undefined symbol: wcslen * * Restart config... * * * General architecture-dependent options * 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 Link Time Optimization (LTO) > 1. None (LTO_NONE) choice[1]: 1 Use Clang's Control Flow Integrity (CFI) (CFI_CLANG) [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 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/?] (NEW) Error in reading or end of file. * * 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. * * Compile-time checks and compiler options * Debug information 1. Disable debug information (DEBUG_INFO_NONE) 2. Rely on the toolchain's implicit default DWARF version (DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT) > 3. Generate DWARF Version 4 debuginfo (DEBUG_INFO_DWARF4) 4. Generate DWARF Version 5 debuginfo (DEBUG_INFO_DWARF5) choice[1-4?]: 3 Reduce debugging information (DEBUG_INFO_REDUCED) [N/y/?] n Compressed Debug information > 1. Don't compress debug information (DEBUG_INFO_COMPRESSED_NONE) 2. Compress debugging information with zlib (DEBUG_INFO_COMPRESSED_ZLIB) 3. Compress debugging information with zstd (DEBUG_INFO_COMPRESSED_ZSTD) (NEW) choice[1-3?]: Error in reading or end of file. Produce split debuginfo in .dwo files (DEBUG_INFO_SPLIT) [N/y/?] n Generate BTF type information (DEBUG_INFO_BTF) [N/y/?] n Provide GDB scripts for kernel debugging (GDB_SCRIPTS) [N/y/?] n Warn for stack frames larger than (FRAME_WARN) [2048] 2048 Strip assembler-generated symbols during link (STRIP_ASM_SYMS) [N/y/?] n Install uapi headers to usr/include (HEADERS_INSTALL) [N/y/?] n Make section mismatch errors non-fatal (SECTION_MISMATCH_WARN_ONLY) [Y/n/?] y Force all function address 64B aligned (DEBUG_FORCE_FUNCTION_ALIGN_64B) [N/y/?] n Generate vmlinux.map file when linking (VMLINUX_MAP) [N/y/?] n Force weak per-cpu definitions (DEBUG_FORCE_WEAK_PER_CPU) [N/y/?] n In file
c1d32b88-1c61-4ad3-8792-3ca4117dbadc assessment-security 💥 INFO: task hung in txBegin 2026/05/15 07:31 2026/05/15 07:31 2026/05/15 07:32 6ccb967e465e832a7bfd7a116ad00d52a0923a5d failed to run ["git" "pull" "origin" "HEAD" "--depth=1" "--allow-unrelated-histories"]: exit status 128 From /app/workdir/repo/linux * branch HEAD -> FETCH_HEAD Updating files: 18% (15383/84960) Updating files: 19% (16143/84960) Updating files: 20% (16992/84960) Updating files: 21% (17842/84960) Updating files: 22% (18692/84960) error: unable to write file arch/mips/include/asm/mach-bcm47xx/bcm47xx.h error: unable to write file arch/mips/include/asm/mach-bcm47xx/bcm47xx_board.h error: unable to write file arch/mips/include/asm/mach-bcm47xx/cpu-feature-overrides.h fatal: cannot create directory at 'arch/mips/include/asm/mach-bcm63xx': No space left on device
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [jfs?] INFO: task hung in txBegin 3 (10) 2024/08/05 12:20
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in txBegin jfs 1 1 1227d 1227d 0/1 upstream: reported on 2023/01/31 18:37
linux-6.1 INFO: task hung in txBegin 1 1 664d 664d 0/3 auto-obsoleted due to no activity on 2024/11/25 05:46
Last patch testing requests (12)
Created Duration User Patch Repo Result
2026/05/08 03:50 24m retest repro upstream report log
2025/09/08 22:47 22m retest repro upstream report log
2025/05/22 08:06 18m retest repro upstream report log
2024/12/30 23:56 20m retest repro upstream report log
2024/10/10 10:37 14m retest repro upstream report log
2024/08/05 11:46 14m eadavis@qq.com patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 50736169ecc8 report log
2024/08/04 07:33 23m eadavis@qq.com patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 50736169ecc8 report log
2024/07/31 03:25 16m retest repro upstream report log
2024/07/20 02:32 14m eadavis@qq.com patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 50736169ecc8 report log
2024/06/27 02:53 19m lizhi.xu@windriver.com patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 50736169ecc8 report log
2024/06/27 01:59 19m lizhi.xu@windriver.com patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 50736169ecc8 error
2024/06/27 00:51 32m lizhi.xu@windriver.com patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 50736169ecc8 error
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2025/03/08 09:05 2h24m bisect fix upstream OK (0) job log
2025/01/26 21:09 3h47m bisect fix upstream OK (0) job log log

Sample crash report:
INFO: task kworker/u8:11:2848 blocked for more than 143 seconds.
      Not tainted 6.10.0-rc4-syzkaller-00148-g50736169ecc8 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:11   state:D stack:23552 pid:2848  tgid:2848  ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0x1796/0x49d0 kernel/sched/core.c:6745
 __schedule_loop kernel/sched/core.c:6822 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6837
 io_schedule+0x8d/0x110 kernel/sched/core.c:9043
 TXN_SLEEP_DROP_LOCK fs/jfs/jfs_txnmgr.c:125 [inline]
 txBegin+0x260/0xce0 fs/jfs/jfs_txnmgr.c:374
 jfs_commit_inode+0x223/0x590 fs/jfs/inode.c:101
 jfs_write_inode+0x143/0x220 fs/jfs/inode.c:132
 write_inode fs/fs-writeback.c:1497 [inline]
 __writeback_single_inode+0x6b9/0x10b0 fs/fs-writeback.c:1716
 writeback_sb_inodes+0x99c/0x1380 fs/fs-writeback.c:1947
 wb_writeback+0x481/0xd40 fs/fs-writeback.c:2127
 wb_do_writeback fs/fs-writeback.c:2274 [inline]
 wb_workfn+0x410/0x1090 fs/fs-writeback.c:2314
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task syz-executor117:5099 blocked for more than 143 seconds.
      Not tainted 6.10.0-rc4-syzkaller-00148-g50736169ecc8 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor117 state:D stack:19408 pid:5099  tgid:5099  ppid:5098   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0x1796/0x49d0 kernel/sched/core.c:6745
 __schedule_loop kernel/sched/core.c:6822 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6837
 wb_wait_for_completion+0x166/0x290 fs/fs-writeback.c:216
 __writeback_inodes_sb_nr+0x2d2/0x380 fs/fs-writeback.c:2706
 sync_filesystem+0xa4/0x230 fs/sync.c:54
 generic_shutdown_super+0x72/0x2d0 fs/super.c:621
 kill_block_super+0x44/0x90 fs/super.c:1676
 deactivate_locked_super+0xc4/0x130 fs/super.c:473
 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1267
 task_work_run+0x24f/0x310 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe052acc017
RSP: 002b:00007ffd7811a4d8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fe052acc017
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd7811a590
RBP: 00007ffd7811a590 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000206 R12: 00007ffd7811b5f0
R13: 00005555816966c0 R14: 000000000000000f R15: 431bde82d7b634db
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
 #0: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
 #0: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614
2 locks held by kworker/u8:11/2848:
 #0: ffff88801ae86148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff88801ae86148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc900098b7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc900098b7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
2 locks held by getty/4845:
 #0: ffff88802a5ab0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002f162f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2211
1 lock held by syz-executor117/5099:
 #0: ffff88802c5e00e0 (&type->s_umount_key#46){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88802c5e00e0 (&type->s_umount_key#46){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88802c5e00e0 (&type->s_umount_key#46){+.+.}-{3:3}, at: deactivate_super+0xb5/0xf0 fs/super.c:505

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 30 Comm: khungtaskd Not tainted 6.10.0-rc4-syzkaller-00148-g50736169ecc8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xfde/0x1020 kernel/hung_task.c:379
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 51 Comm: kworker/u8:3 Not tainted 6.10.0-rc4-syzkaller-00148-g50736169ecc8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x0/0x90 kernel/kcov.c:310
Code: 10 48 89 74 0a 18 4c 89 44 0a 20 c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 4c 8b 04 24 65 48 8b 0c 25 80 d4 03 00 65 8b 05 f0 aa
RSP: 0018:ffffc90000bb7638 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 000ffffffffff000 RCX: ffff888015193c00
RDX: 000000001507c558 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000bb7730 R08: ffffffff81e6dded R09: 1ffffffff25edcb0
R10: dffffc0000000000 R11: fffffbfff25edcb1 R12: 1ffff92000176ed0
R13: 000000001507c067 R14: 0000000000000000 R15: 1ffff92000176ed8
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005617e0440680 CR3: 000000000e132000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 pmd_pfn_mask arch/x86/include/asm/pgtable_types.h:453 [inline]
 pmd_pfn arch/x86/include/asm/pgtable.h:234 [inline]
 pte_lockptr include/linux/mm.h:2955 [inline]
 __pte_offset_map_lock+0x17b/0x300 mm/pgtable-generic.c:374
 get_locked_pte include/linux/mm.h:2744 [inline]
 __text_poke+0x2c5/0xd30 arch/x86/kernel/alternative.c:1883
 text_poke arch/x86/kernel/alternative.c:1968 [inline]
 text_poke_bp_batch+0x8cd/0xb30 arch/x86/kernel/alternative.c:2357
 text_poke_flush arch/x86/kernel/alternative.c:2470 [inline]
 text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2477
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:205
 static_key_enable+0x1a/0x20 kernel/jump_label.c:218
 toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:826
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.555 msecs

Crashes (194):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/21 15:24 upstream 50736169ecc8 dac2aa43 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs INFO: task hung in txBegin
2026/06/11 17:44 upstream 9716c086c8e8 d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/10 19:58 upstream acb7500801e9 f79bac11 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/10 04:54 upstream 685441a6d3f1 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/09 08:01 upstream 2d3090a8aeb5 656e94c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/08 13:44 upstream 4549871118cf cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/08 02:23 upstream 33d8d8ec31b5 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/07 21:57 upstream 33d8d8ec31b5 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/07 17:38 upstream 33d8d8ec31b5 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/07 04:21 upstream 979c294509f9 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/05 15:31 upstream ddd664bbff63 48b6c3fa .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/05 09:56 upstream ddd664bbff63 197909be .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/05 03:45 upstream 9154c4af7829 197909be .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/04 10:39 upstream ba3e43a9e601 197909be .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/04 06:57 upstream ba3e43a9e601 197909be .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/04 03:53 upstream ba3e43a9e601 197909be .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/04 00:43 upstream ba3e43a9e601 197909be .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/03 09:09 upstream ba3e43a9e601 3c0d2131 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/02 07:53 upstream 6f3ed7fec72f 1095583b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/06/01 03:59 upstream e43ffb69e043 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/05/30 22:21 upstream f5e5d3509bff 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/05/30 03:04 upstream 9215e74f228f 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/05/30 01:09 upstream 9215e74f228f 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/05/29 18:48 upstream 8fde5d1d47f6 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/05/29 11:23 upstream 8fde5d1d47f6 4624854e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/05/29 06:32 upstream 8fde5d1d47f6 4624854e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/05/28 22:22 upstream 8fde5d1d47f6 681715f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/05/28 01:52 upstream eb3f4b7426cf 4c36e7e5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/17 04:45 upstream 3cd8b194bf34 de0a551d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/15 20:47 upstream 1f5ffc672165 c441f497 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/15 15:39 upstream 1f5ffc672165 c441f497 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/15 02:17 upstream 508fed679541 e2e976a8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/12 01:49 upstream e753c16cb3dd 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/10 10:03 upstream 9a9c8ce300cd 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/08 04:00 upstream 3036cd0d3328 2c961e87 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/07 20:28 upstream 3036cd0d3328 628666c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/05 18:29 upstream 1791c390149f 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/05 17:29 upstream 3aae9383f42f 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/04 15:54 upstream 7ca6d1cfec80 4440e7c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/02 06:14 upstream 9147566d8016 0cb124d5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/02 00:31 upstream 9147566d8016 0cb124d5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/04/01 00:43 upstream dbf00d8d23b4 fb8b2c26 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/03/28 07:02 upstream 7df48e363130 356bdfc9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/03/27 02:40 upstream 46b513250491 766b6434 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/03/26 13:20 upstream 0138af2472df 766b6434 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2026/03/26 01:45 upstream d2a43e7f89da c6143aac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in txBegin
2025/07/11 23:57 upstream 40f92e79b0aa 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in txBegin
2024/06/07 16:14 upstream 8a92980606e3 121701b6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in txBegin
2024/05/22 17:53 upstream 8f6a15f095a6 4d098039 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in txBegin
2024/05/17 21:07 upstream ff2632d7d08e a12e99e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in txBegin
2026/01/15 09:22 linux-next 9b7977f9e39b d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in txBegin
* Struck through repros no longer work on HEAD.