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INFO: task hung in generic_file_write_iter

Status: auto-closed as invalid on 2019/02/22 14:09
First crash: 2067d, last: 2066d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in generic_file_write_iter (2) fs 1 535d 535d 0/26 auto-obsoleted due to no activity on 2023/02/10 17:47
upstream INFO: task hung in generic_file_write_iter fs mm 7 1962d 2100d 11/26 fixed on 2019/03/06 07:43

Sample crash report:
b_state=0x00000029, b_size=512
device loop0 blocksize: 2048
__find_get_block_slow() failed. block=2, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 2048
INFO: task syz-executor0:1868 blocked for more than 140 seconds.
      Not tainted 4.9.122-g54068d6 #26
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D28648  1868    633 0x00000004
 ffff8801d423c800 0000000000000000 ffff880198810000 ffff8801d55e6000
 ffff8801db321c18 ffff880199367418 ffffffff839efdcd ffffffff812378c7
 0000000000000000 ffff8801d423d0c0 0000000600000007 ffff8801db3224e8
Call Trace:
 [<ffffffff839f13cf>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff839fca08>] __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:526 [inline]
 [<ffffffff839fca08>] rwsem_down_write_failed+0x598/0x990 kernel/locking/rwsem-xadd.c:555
 [<ffffffff81eecb47>] call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105
 [<ffffffff839fa7dc>] __down_write arch/x86/include/asm/rwsem.h:125 [inline]
 [<ffffffff839fa7dc>] down_write+0x5c/0xa0 kernel/locking/rwsem.c:54
 [<ffffffff8144001d>] inode_lock include/linux/fs.h:766 [inline]
 [<ffffffff8144001d>] generic_file_write_iter+0x9d/0x610 mm/filemap.c:2903
 [<ffffffff815727a0>] new_sync_write fs/read_write.c:496 [inline]
 [<ffffffff815727a0>] __vfs_write+0x3e0/0x580 fs/read_write.c:509
 [<ffffffff81574f30>] __kernel_write+0xf0/0x340 fs/read_write.c:529
 [<ffffffff816187ad>] write_pipe_buf+0x15d/0x1f0 fs/splice.c:816
 [<ffffffff816197b6>] splice_from_pipe_feed fs/splice.c:521 [inline]
 [<ffffffff816197b6>] __splice_from_pipe+0x316/0x710 fs/splice.c:645
 [<ffffffff8161bcf9>] splice_from_pipe+0xf9/0x170 fs/splice.c:680
 [<ffffffff8161bdfc>] default_file_splice_write+0x3c/0x80 fs/splice.c:828
 [<ffffffff81616398>] do_splice_from fs/splice.c:870 [inline]
 [<ffffffff81616398>] direct_splice_actor+0x128/0x190 fs/splice.c:1037
 [<ffffffff816176e1>] splice_direct_to_actor+0x2c1/0x7e0 fs/splice.c:992
 [<ffffffff81617da3>] do_splice_direct+0x1a3/0x270 fs/splice.c:1080
 [<ffffffff81579170>] do_sendfile+0x4f0/0xc60 fs/read_write.c:1393
 [<ffffffff8157b1f1>] SYSC_sendfile64 fs/read_write.c:1448 [inline]
 [<ffffffff8157b1f1>] SyS_sendfile64+0xd1/0x160 fs/read_write.c:1440
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff83a00cd3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/519:
 #0:  (rcu_read_lock){......}, at: [<ffffffff81368a5c>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff81368a5c>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff814282c8>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/3682:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815dbb4c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/3779:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839fee72>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff82124562>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
2 locks held by syz-executor0/1868:
 #0:  (sb_writers#11){.+.+.+}, at: [<ffffffff81579598>] file_start_write include/linux/fs.h:2640 [inline]
 #0:  (sb_writers#11){.+.+.+}, at: [<ffffffff81579598>] do_sendfile+0x918/0xc60 fs/read_write.c:1392
 #1:  (&sb->s_type->i_mutex_key#20){++++++}, at: [<ffffffff8144001d>] inode_lock include/linux/fs.h:766 [inline]
 #1:  (&sb->s_type->i_mutex_key#20){++++++}, at: [<ffffffff8144001d>] generic_file_write_iter+0x9d/0x610 mm/filemap.c:2903

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

NMI backtrace for cpu 1
CPU: 1 PID: 519 Comm: khungtaskd Not tainted 4.9.122-g54068d6 #26
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d850fd08 ffffffff81eb8829 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b9fa0 ffff8801d850fd40
 ffffffff81ec3b67 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb8829>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb8829>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ec3b67>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ec3afa>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810ba0a4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81368ff4>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81368ff4>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81368ff4>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81368ff4>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119f38d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff83a00e9c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 1844 Comm: syz-executor0 Not tainted 4.9.122-g54068d6 #26
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d6cd4800 task.stack: ffff88019b300000
RIP: 0010:[<ffffffff8215533b>] c [<ffffffff8215533b>] inb arch/x86/include/asm/io.h:316 [inline]
RIP: 0010:[<ffffffff8215533b>] c [<ffffffff8215533b>] io_serial_in+0x6b/0x90 drivers/tty/serial/8250/8250_port.c:414
RSP: 0018:ffff88019b306698  EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffffff821552e1 RDI: ffffffff864ace78
RBP: ffff88019b3066a8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff864ace40
R13: 0000000000000020 R14: fffffbfff0c95a0f R15: fffffbfff0c959d1
FS:  00007f513b05d700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f065df7c000 CR3: 00000001cdf97000 CR4: 00000000001606f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Stack:
 ffffffff864ace40c 000000000000270ac ffff88019b3066f8c ffffffff82156f04c
 ffffffff81ee3b58c ffffffff864ace88c ffffffff864ad07ac ffffffff864ace40c
 0000000000000061c ffffffff82157050c dffffc0000000000c 0000000000000061c
Call Trace:
 [<ffffffff82156f04>] serial_in drivers/tty/serial/8250/8250.h:111 [inline]
 [<ffffffff82156f04>] wait_for_xmitr+0x94/0x1e0 drivers/tty/serial/8250/8250_port.c:1998
 [<ffffffff8215706f>] serial8250_console_putchar+0x1f/0x60 drivers/tty/serial/8250/8250_port.c:3104
 [<ffffffff8213f899>] uart_console_write+0x59/0xf0 drivers/tty/serial/serial_core.c:1859
 [<ffffffff82163288>] serial8250_console_write+0x528/0x820 drivers/tty/serial/8250/8250_port.c:3170
 [<ffffffff8214fdef>] univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:594
 [<ffffffff8125df4d>] call_console_drivers.isra.18.constprop.28+0x1ad/0x360 kernel/printk/printk.c:1589
 [<ffffffff81260d4f>] console_unlock+0x42f/0xb40 kernel/printk/printk.c:2449
 [<ffffffff812618a8>] vprintk_emit+0x448/0x790 kernel/printk/printk.c:1903
 [<ffffffff81261c18>] vprintk+0x28/0x30 kernel/printk/printk.c:1913
 [<ffffffff81261c3d>] vprintk_default+0x1d/0x30 kernel/printk/printk.c:1914
 [<ffffffff8142f09d>] vprintk_func kernel/printk/internal.h:36 [inline]
 [<ffffffff8142f09d>] printk+0xaf/0xd7 kernel/printk/printk.c:1975
 [<ffffffff81cc40b4>] fat_msg+0xdc/0x110 fs/fat/misc.c:54
 [<ffffffff81cc41f1>] __fat_fs_error+0x109/0x208 fs/fat/misc.c:29
 [<ffffffff818ba945>] fat_get_cluster+0xa15/0xbc0 fs/fat/cache.c:263
 [<ffffffff818dafb5>] fat_chain_add+0x395/0x610 fs/fat/misc.c:113
 [<ffffffff818d81af>] fat_add_cluster+0xbf/0xe0 fs/fat/inode.c:105
 [<ffffffff818d84af>] __fat_get_block fs/fat/inode.c:147 [inline]
 [<ffffffff818d84af>] fat_get_block+0x2df/0x800 fs/fat/inode.c:176
 [<ffffffff8162da31>] __block_write_begin_int+0x391/0x1040 fs/buffer.c:1987
 [<ffffffff8162e77f>] __block_write_begin fs/buffer.c:2038 [inline]
 [<ffffffff8162e77f>] block_write_begin+0x5f/0x180 fs/buffer.c:2097
 [<ffffffff8162ed93>] cont_write_begin+0x4f3/0x810 fs/buffer.c:2450
 [<ffffffff818d45ea>] fat_write_begin+0x9a/0x120 fs/fat/inode.c:222
 [<ffffffff81438281>] generic_perform_write+0x301/0x510 mm/filemap.c:2753
 [<ffffffff8143fd92>] __generic_file_write_iter+0x352/0x540 mm/filemap.c:2878
 [<ffffffff81440260>] generic_file_write_iter+0x2e0/0x610 mm/filemap.c:2906
 [<ffffffff815727a0>] new_sync_write fs/read_write.c:496 [inline]
 [<ffffffff815727a0>] __vfs_write+0x3e0/0x580 fs/read_write.c:509
 [<ffffffff81574f30>] __kernel_write+0xf0/0x340 fs/read_write.c:529
 [<ffffffff816187ad>] write_pipe_buf+0x15d/0x1f0 fs/splice.c:816
 [<ffffffff816197b6>] splice_from_pipe_feed fs/splice.c:521 [inline]
 [<ffffffff816197b6>] __splice_from_pipe+0x316/0x710 fs/splice.c:645
 [<ffffffff8161bcf9>] splice_from_pipe+0xf9/0x170 fs/splice.c:680
 [<ffffffff8161bdfc>] default_file_splice_write+0x3c/0x80 fs/splice.c:828
 [<ffffffff81616398>] do_splice_from fs/splice.c:870 [inline]
 [<ffffffff81616398>] direct_splice_actor+0x128/0x190 fs/splice.c:1037
 [<ffffffff816176e1>] splice_direct_to_actor+0x2c1/0x7e0 fs/splice.c:992
 [<ffffffff81617da3>] do_splice_direct+0x1a3/0x270 fs/splice.c:1080
 [<ffffffff81579170>] do_sendfile+0x4f0/0xc60 fs/read_write.c:1393
 [<ffffffff8157b1f1>] SYSC_sendfile64 fs/read_write.c:1448 [inline]
 [<ffffffff8157b1f1>] SyS_sendfile64+0xd1/0x160 fs/read_write.c:1440
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff83a00cd3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: c24 cc9 c00 c00 c00 c49 c8d c7c c24 c38 c48 cb8 c00 c00 c00 c00 c00 cfc cff cdf c48 c89 cfa c48 cc1 cea c03 cd3 ce3 c80 c3c c02 c00 c75 c17 c41 c03 c5c c24 c38 c89 cda cec c<5b> c0f cb6 cc0 c41 c5c c5d cc3 ce8 c48 c9f c3e cff ceb cc2 ce8 ca1 c9f c3e cff ceb c

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/08/21 21:12 https://android.googlesource.com/kernel/common android-4.9 54068d61e7d8 95b5c82b .config console log report ci-android-49-kasan-gce-root
2018/08/21 01:40 https://android.googlesource.com/kernel/common android-4.9 54068d61e7d8 95b5c82b .config console log report ci-android-49-kasan-gce-root
* Struck through repros no longer work on HEAD.