* Re: [syzbot] [reiserfs?] possible deadlock in super_lock [not found] <20230923040320.1384-1-hdanton@sina.com> @ 2023-09-23 4:26 ` syzbot 0 siblings, 0 replies; 15+ messages in thread From: syzbot @ 2023-09-23 4:26 UTC (permalink / raw) To: hdanton, linux-kernel, syzkaller-bugs Hello, syzbot has tested the proposed patch and the reproducer did not trigger any issue: Reported-and-tested-by: syzbot+062317ea1d0a6d5e29e7@syzkaller.appspotmail.com Tested on: commit: 2cf0f715 Merge tag 'nfs-for-6.6-2' of git://git.linux-.. git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git console output: https://syzkaller.appspot.com/x/log.txt?x=15916ee4680000 kernel config: https://syzkaller.appspot.com/x/.config?x=710dc49bece494df dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 patch: https://syzkaller.appspot.com/x/patch.diff?x=16a02f0e680000 Note: testing is done by a robot and is best-effort only. ^ permalink raw reply [flat|nested] 15+ messages in thread
[parent not found: <20231010111343.2257-1-hdanton@sina.com>]
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock [not found] <20231010111343.2257-1-hdanton@sina.com> @ 2023-10-10 11:49 ` syzbot 0 siblings, 0 replies; 15+ messages in thread From: syzbot @ 2023-10-10 11:49 UTC (permalink / raw) To: hdanton, linux-kernel, syzkaller-bugs Hello, syzbot has tested the proposed patch and the reproducer did not trigger any issue: Reported-and-tested-by: syzbot+062317ea1d0a6d5e29e7@syzkaller.appspotmail.com Tested on: commit: 94f6f055 Linux 6.6-rc5 git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master console output: https://syzkaller.appspot.com/x/log.txt?x=159efc7e680000 kernel config: https://syzkaller.appspot.com/x/.config?x=1b8c825e0d5f3f72 dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: arm64 patch: https://syzkaller.appspot.com/x/patch.diff?x=15784cde680000 Note: testing is done by a robot and is best-effort only. ^ permalink raw reply [flat|nested] 15+ messages in thread
[parent not found: <20231009112906.2143-1-hdanton@sina.com>]
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock [not found] <20231009112906.2143-1-hdanton@sina.com> @ 2023-10-09 14:01 ` syzbot 0 siblings, 0 replies; 15+ messages in thread From: syzbot @ 2023-10-09 14:01 UTC (permalink / raw) To: hdanton, linux-kernel, syzkaller-bugs Hello, syzbot has tested the proposed patch but the reproducer is still triggering an issue: WARNING in fs_bdev_sync ------------[ cut here ]------------ WARNING: CPU: 0 PID: 6681 at fs/super.c:1464 fs_bdev_sync+0x138/0x168 fs/super.c:1464 Modules linked in: CPU: 0 PID: 6681 Comm: syz-executor.4 Not tainted 6.6.0-rc5-syzkaller-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : fs_bdev_sync+0x138/0x168 fs/super.c:1464 lr : fs_bdev_sync+0x138/0x168 fs/super.c:1464 sp : ffff800097637a70 x29: ffff800097637a70 x28: ffff0000d6699bc0 x27: 0000000000000003 x26: dfff800000000000 x25: ffff700012ec6f58 x24: ffff800097637ac0 x23: 0000000000001261 x22: dfff800000000000 x21: 0000000000000001 x20: 0000000000000000 x19: ffff0000c657c000 x18: 0000000000000000 x17: 0000000000000000 x16: ffff80008031d534 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: 00000000c0101282 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000 x8 : ffff0000d6699bc0 x7 : 0000000000000000 x6 : 000000000000003f x5 : 0000000000000040 x4 : ffffffffffffffff x3 : 0000000000000000 x2 : 0000000000000015 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: fs_bdev_sync+0x138/0x168 fs/super.c:1464 blkdev_flushbuf block/ioctl.c:371 [inline] blkdev_common_ioctl+0x838/0x286c block/ioctl.c:500 blkdev_ioctl+0x35c/0xae4 block/ioctl.c:622 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:857 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 irq event stamp: 116 hardirqs last enabled at (115): [<ffff8000809cd760>] kasan_quarantine_put+0x1a0/0x1c8 mm/kasan/quarantine.c:240 hardirqs last disabled at (116): [<ffff80008a630728>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:436 softirqs last enabled at (92): [<ffff800080033cf4>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32 softirqs last disabled at (90): [<ffff800080033cc0>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 ---[ end trace 0000000000000000 ]--- Tested on: commit: 94f6f055 Linux 6.6-rc5 git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master console output: https://syzkaller.appspot.com/x/log.txt?x=129ec4e9680000 kernel config: https://syzkaller.appspot.com/x/.config?x=1b8c825e0d5f3f72 dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: arm64 patch: https://syzkaller.appspot.com/x/patch.diff?x=156813ee680000 ^ permalink raw reply [flat|nested] 15+ messages in thread
[parent not found: <20230923024635.1249-1-hdanton@sina.com>]
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock [not found] <20230923024635.1249-1-hdanton@sina.com> @ 2023-09-23 3:02 ` syzbot 0 siblings, 0 replies; 15+ messages in thread From: syzbot @ 2023-09-23 3:02 UTC (permalink / raw) To: hdanton, linux-kernel, syzkaller-bugs Hello, syzbot has tested the proposed patch but the reproducer is still triggering an issue: WARNING in dquot_disable ------------[ cut here ]------------ WARNING: CPU: 0 PID: 5401 at fs/quota/dquot.c:2217 dquot_disable+0xff1/0x1710 fs/quota/dquot.c:2217 Modules linked in: CPU: 0 PID: 5401 Comm: syz-executor.0 Not tainted 6.6.0-rc2-syzkaller-00018-g2cf0f7156238-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 RIP: 0010:dquot_disable+0xff1/0x1710 fs/quota/dquot.c:2217 Code: d2 0f 85 fd 04 00 00 8b 15 48 34 c1 0c 48 c7 c6 ff ff ff ff 48 c7 c7 a0 f4 34 92 e8 19 41 46 02 e9 6f f7 ff ff e8 4f 43 7a ff <0f> 0b 48 89 ef e8 25 95 59 ff e9 a6 f0 ff ff e8 3b 43 7a ff 4c 8d RSP: 0018:ffffc9000382fb60 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000 RDX: ffff8880287c0140 RSI: ffffffff820c8201 RDI: 0000000000000005 RBP: ffff888077efc070 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: ffff888077efc000 R14: ffffffff8aa27800 R15: 1ffff92000705f79 FS: 0000555555e27480(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb752142378 CR3: 00000000212c7000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> reiserfs_quota_off+0x11f/0x160 fs/reiserfs/super.c:2480 reiserfs_quota_off_umount fs/reiserfs/super.c:581 [inline] reiserfs_put_super+0x8f/0x5c0 fs/reiserfs/super.c:594 generic_shutdown_super+0x2ab/0x400 fs/super.c:727 kill_block_super+0x3b/0x70 fs/super.c:1650 deactivate_locked_super+0x9a/0x170 fs/super.c:481 deactivate_super+0xde/0x100 fs/super.c:514 cleanup_mnt+0x222/0x3d0 fs/namespace.c:1254 task_work_run+0x14d/0x240 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7effb087de17 Code: b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b0 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffc59c8ec28 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007effb087de17 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffc59c8ece0 RBP: 00007ffc59c8ece0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc59c8fda0 R13: 00007effb08c73b9 R14: 000000000001d8a7 R15: 0000000000000005 </TASK> Tested on: commit: 2cf0f715 Merge tag 'nfs-for-6.6-2' of git://git.linux-.. git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git console output: https://syzkaller.appspot.com/x/log.txt?x=17d0480a680000 kernel config: https://syzkaller.appspot.com/x/.config?x=710dc49bece494df dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 patch: https://syzkaller.appspot.com/x/patch.diff?x=11959f5c680000 ^ permalink raw reply [flat|nested] 15+ messages in thread
[parent not found: <20230923010437.297-1-hdanton@sina.com>]
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock [not found] <20230923010437.297-1-hdanton@sina.com> @ 2023-09-23 1:14 ` syzbot 0 siblings, 0 replies; 15+ messages in thread From: syzbot @ 2023-09-23 1:14 UTC (permalink / raw) To: hdanton, linux-kernel, syzkaller-bugs Hello, syzbot tried to test the proposed patch but the build/boot failed: fs/super.c:663:9: error: 'put' undeclared (first use in this function); did you mean 'fput'? Tested on: commit: 2cf0f715 Merge tag 'nfs-for-6.6-2' of git://git.linux-.. git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git kernel config: https://syzkaller.appspot.com/x/.config?x=710dc49bece494df dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 patch: https://syzkaller.appspot.com/x/patch.diff?x=14cc0642680000 ^ permalink raw reply [flat|nested] 15+ messages in thread
[parent not found: <20230922124125.240-1-hdanton@sina.com>]
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock [not found] <20230922124125.240-1-hdanton@sina.com> @ 2023-09-22 13:11 ` syzbot 0 siblings, 0 replies; 15+ messages in thread From: syzbot @ 2023-09-22 13:11 UTC (permalink / raw) To: hdanton, linux-kernel, syzkaller-bugs Hello, syzbot tried to test the proposed patch but the build/boot failed: : Allocated hash algorithm: sha256 [ 27.035992][ T1] ima: No architecture policies found [ 27.042240][ T1] evm: Initialising EVM extended attributes: [ 27.048580][ T1] evm: security.selinux [ 27.052744][ T1] evm: security.SMACK64 (disabled) [ 27.058061][ T1] evm: security.SMACK64EXEC (disabled) [ 27.063553][ T1] evm: security.SMACK64TRANSMUTE (disabled) [ 27.069527][ T1] evm: security.SMACK64MMAP (disabled) [ 27.075116][ T1] evm: security.apparmor (disabled) [ 27.080399][ T1] evm: security.ima [ 27.084710][ T1] evm: security.capability [ 27.090479][ T1] evm: HMAC attrs: 0x1 [ 27.097685][ T1] PM: Magic number: 7:13:29 [ 27.103531][ T1] tty ttydc: hash matches [ 27.108483][ T1] memory memory69: hash matches [ 27.115959][ T1] printk: console [netcon0] enabled [ 27.121787][ T1] netconsole: network logging started [ 27.128754][ T1] gtp: GTP module loaded (pdp ctx size 104 bytes) [ 27.137889][ T1] rdma_rxe: loaded [ 27.142619][ T1] cfg80211: Loading compiled-in X.509 certificates for regulatory database [ 27.155065][ T1] Loaded X.509 cert 'sforshee: 00b28ddf47aef9cea7' [ 27.165314][ T1] clk: Disabling unused clocks [ 27.165914][ T921] platform regulatory.0: Direct firmware load for regulatory.db failed with error -2 [ 27.170274][ T1] ALSA device list: [ 27.180256][ T921] platform regulatory.0: Falling back to sysfs fallback for: regulatory.db [ 27.184543][ T1] #0: Dummy 1 [ 27.184558][ T1] #1: Loopback 1 [ 27.184570][ T1] #2: Virtual MIDI Card 1 [ 27.212250][ T1] md: Waiting for all devices to be available before autodetect [ 27.220507][ T1] md: If you don't use raid, use raid=noautodetect [ 27.227162][ T1] md: Autodetecting RAID arrays. [ 27.232319][ T1] md: autorun ... [ 27.236020][ T1] md: ... autorun DONE. [ 27.282766][ T1] [ 27.285112][ T1] ===================================== [ 27.290728][ T1] WARNING: bad unlock balance detected! [ 27.296371][ T1] 6.6.0-rc2-syzkaller-00018-g2cf0f7156238-dirty #0 Not tainted [ 27.304445][ T1] ------------------------------------- [ 27.310421][ T1] swapper/0/1 is trying to release lock (&type->s_umount_key) at: [ 27.318241][ T1] [<ffffffff81eb7734>] generic_shutdown_super+0x1e4/0x3c0 [ 27.325454][ T1] but there are no more locks to release! [ 27.331175][ T1] [ 27.331175][ T1] other info that might help us debug this: [ 27.339755][ T1] no locks held by swapper/0/1. [ 27.344702][ T1] [ 27.344702][ T1] stack backtrace: [ 27.351193][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.6.0-rc2-syzkaller-00018-g2cf0f7156238-dirty #0 [ 27.361550][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 [ 27.371784][ T1] Call Trace: [ 27.375057][ T1] <TASK> [ 27.377991][ T1] dump_stack_lvl+0xd9/0x1b0 [ 27.382775][ T1] lock_release+0x4b5/0x680 [ 27.387307][ T1] ? generic_shutdown_super+0x1e4/0x3c0 [ 27.393046][ T1] ? reacquire_held_locks+0x4b0/0x4b0 [ 27.399133][ T1] ? reacquire_held_locks+0x4b0/0x4b0 [ 27.404517][ T1] ? __wake_up_sync+0x20/0x20 [ 27.409379][ T1] up_write+0x2a/0x510 [ 27.413447][ T1] ? reiserfs_remount+0x1640/0x1640 [ 27.418761][ T1] generic_shutdown_super+0x1e4/0x3c0 [ 27.424293][ T1] ? reiserfs_remount+0x1640/0x1640 [ 27.429818][ T1] kill_block_super+0x3b/0x70 [ 27.434502][ T1] deactivate_locked_super+0xa6/0x180 [ 27.439882][ T1] mount_bdev+0x2a6/0x300 [ 27.444306][ T1] ? sget+0x610/0x610 [ 27.448361][ T1] ? vfs_parse_fs_param+0x3c0/0x3c0 [ 27.453617][ T1] ? cap_capable+0x1d8/0x240 [ 27.458237][ T1] ? reiserfs_kill_sb+0x1e0/0x1e0 [ 27.463792][ T1] legacy_get_tree+0x109/0x220 [ 27.468671][ T1] vfs_get_tree+0x8c/0x370 [ 27.473205][ T1] path_mount+0x1492/0x1ed0 [ 27.477749][ T1] ? kmem_cache_free+0x223/0x380 [ 27.482713][ T1] ? finish_automount+0xa40/0xa40 [ 27.487868][ T1] ? putname+0x101/0x140 [ 27.492574][ T1] init_mount+0xbf/0x110 [ 27.497105][ T1] ? nsfs_init+0xb0/0xb0 [ 27.501361][ T1] do_mount_root+0xdd/0x2c0 [ 27.506048][ T1] mount_root_generic+0x19a/0x460 [ 27.511083][ T1] ? init_rootfs+0x60/0x60 [ 27.515515][ T1] ? getname_kernel+0x21c/0x360 [ 27.520369][ T1] mount_root+0x241/0x480 [ 27.524697][ T1] ? kmem_cache_alloc+0x338/0x400 [ 27.529717][ T1] ? mount_root_generic+0x460/0x460 [ 27.535001][ T1] ? getname_kernel+0x21c/0x360 [ 27.539945][ T1] prepare_namespace+0xe3/0x3f0 [ 27.544896][ T1] ? mount_root+0x480/0x480 [ 27.549494][ T1] ? fput+0x30/0x1a0 [ 27.553394][ T1] kernel_init_freeable+0x703/0x8f0 [ 27.558596][ T1] ? rest_init+0x2b0/0x2b0 [ 27.563016][ T1] kernel_init+0x1c/0x2a0 [ 27.567351][ T1] ? rest_init+0x2b0/0x2b0 [ 27.571769][ T1] ret_from_fork+0x45/0x80 [ 27.576365][ T1] ? rest_init+0x2b0/0x2b0 [ 27.580799][ T1] ret_from_fork_asm+0x11/0x20 [ 27.585674][ T1] </TASK> [ 27.588872][ T1] ------------[ cut here ]------------ [ 27.594557][ T1] DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff88814be20070, owner = 0x0, curr 0xffff888019644040, list empty [ 27.613588][ T1] WARNING: CPU: 0 PID: 1 at kernel/locking/rwsem.c:1369 up_write+0x458/0x510 [ 27.622528][ T1] Modules linked in: [ 27.626442][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.6.0-rc2-syzkaller-00018-g2cf0f7156238-dirty #0 [ 27.637061][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 [ 27.648689][ T1] RIP: 0010:up_write+0x458/0x510 [ 27.653883][ T1] Code: c1 ea 03 80 3c 02 00 75 50 48 8b 13 4d 89 f1 41 55 4d 89 f8 4c 89 e1 48 c7 c6 e0 93 8c 8a 48 c7 c7 00 93 8c 8a e8 e8 e1 e6 ff <0f> 0b 5a e9 aa fc ff ff 48 89 ef e8 28 9f 75 00 e9 17 fd ff ff 48 [ 27.674317][ T1] RSP: 0000:ffffc9000027f910 EFLAGS: 00010286 [ 27.680635][ T1] RAX: 0000000000000000 RBX: ffff88814be20070 RCX: 0000000000000000 [ 27.688711][ T1] RDX: ffff888019644040 RSI: ffffffff814cf096 RDI: 0000000000000001 [ 27.696725][ T1] RBP: ffff88814be20078 R08: 0000000000000001 R09: 0000000000000000 [ 27.704906][ T1] R10: 0000000000000001 R11: 0000000000000001 R12: ffff88814be20070 [ 27.713404][ T1] R13: ffffffff8a8c9240 R14: ffff888019644040 R15: 0000000000000000 [ 27.721412][ T1] FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 [ 27.730905][ T1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 27.737626][ T1] CR2: ffff88823ffff000 CR3: 000000000c976000 CR4: 00000000003506f0 [ 27.746689][ T1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 27.754948][ T1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 27.762933][ T1] Call Trace: [ 27.766295][ T1] <TASK> [ 27.769274][ T1] ? show_regs+0x8f/0xa0 [ 27.773712][ T1] ? __warn+0xe6/0x380 [ 27.777946][ T1] ? up_write+0x458/0x510 [ 27.782348][ T1] ? report_bug+0x3bc/0x580 [ 27.786873][ T1] ? handle_bug+0x3c/0x70 [ 27.791192][ T1] ? exc_invalid_op+0x17/0x40 [ 27.795896][ T1] ? asm_exc_invalid_op+0x1a/0x20 [ 27.800980][ T1] ? __warn_printk+0x1a6/0x350 [ 27.805772][ T1] ? up_write+0x458/0x510 [ 27.810110][ T1] ? reiserfs_remount+0x1640/0x1640 [ 27.815343][ T1] generic_shutdown_super+0x1e4/0x3c0 [ 27.820737][ T1] ? reiserfs_remount+0x1640/0x1640 [ 27.826056][ T1] kill_block_super+0x3b/0x70 [ 27.830828][ T1] deactivate_locked_super+0xa6/0x180 [ 27.836220][ T1] mount_bdev+0x2a6/0x300 [ 27.840537][ T1] ? sget+0x610/0x610 [ 27.844534][ T1] ? vfs_parse_fs_param+0x3c0/0x3c0 [ 27.849831][ T1] ? cap_capable+0x1d8/0x240 [ 27.854439][ T1] ? reiserfs_kill_sb+0x1e0/0x1e0 [ 27.859490][ T1] legacy_get_tree+0x109/0x220 [ 27.864358][ T1] vfs_get_tree+0x8c/0x370 [ 27.868886][ T1] path_mount+0x1492/0x1ed0 [ 27.873441][ T1] ? kmem_cache_free+0x223/0x380 [ 27.878456][ T1] ? finish_automount+0xa40/0xa40 [ 27.883647][ T1] ? putname+0x101/0x140 [ 27.887917][ T1] init_mount+0xbf/0x110 [ 27.892230][ T1] ? nsfs_init+0xb0/0xb0 [ 27.896498][ T1] do_mount_root+0xdd/0x2c0 [ 27.901004][ T1] mount_root_generic+0x19a/0x460 [ 27.906042][ T1] ? init_rootfs+0x60/0x60 [ 27.910526][ T1] ? getname_kernel+0x21c/0x360 [ 27.915727][ T1] mount_root+0x241/0x480 [ 27.920314][ T1] ? kmem_cache_alloc+0x338/0x400 [ 27.925350][ T1] ? mount_root_generic+0x460/0x460 [ 27.930895][ T1] ? getname_kernel+0x21c/0x360 [ 27.936002][ T1] prepare_namespace+0xe3/0x3f0 [ 27.941118][ T1] ? mount_root+0x480/0x480 [ 27.945751][ T1] ? fput+0x30/0x1a0 [ 27.949754][ T1] kernel_init_freeable+0x703/0x8f0 [ 27.954988][ T1] ? rest_init+0x2b0/0x2b0 [ 27.959460][ T1] kernel_init+0x1c/0x2a0 [ 27.963999][ T1] ? rest_init+0x2b0/0x2b0 [ 27.969519][ T1] ret_from_fork+0x45/0x80 [ 27.974142][ T1] ? rest_init+0x2b0/0x2b0 [ 27.978650][ T1] ret_from_fork_asm+0x11/0x20 [ 27.983604][ T1] </TASK> [ 27.986619][ T1] Kernel panic - not syncing: kernel: panic_on_warn set ... [ 27.994750][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.6.0-rc2-syzkaller-00018-g2cf0f7156238-dirty #0 [ 28.005187][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 [ 28.015864][ T1] Call Trace: [ 28.019651][ T1] <TASK> [ 28.022839][ T1] dump_stack_lvl+0xd9/0x1b0 [ 28.027529][ T1] panic+0x6a6/0x750 [ 28.032304][ T1] ? panic_smp_self_stop+0xa0/0xa0 [ 28.037525][ T1] ? up_write+0x458/0x510 [ 28.042116][ T1] check_panic_on_warn+0xab/0xb0 [ 28.047062][ T1] __warn+0xf2/0x380 [ 28.050976][ T1] ? up_write+0x458/0x510 [ 28.055569][ T1] report_bug+0x3bc/0x580 [ 28.060442][ T1] handle_bug+0x3c/0x70 [ 28.065044][ T1] exc_invalid_op+0x17/0x40 [ 28.070109][ T1] asm_exc_invalid_op+0x1a/0x20 [ 28.074971][ T1] RIP: 0010:up_write+0x458/0x510 [ 28.080204][ T1] Code: c1 ea 03 80 3c 02 00 75 50 48 8b 13 4d 89 f1 41 55 4d 89 f8 4c 89 e1 48 c7 c6 e0 93 8c 8a 48 c7 c7 00 93 8c 8a e8 e8 e1 e6 ff <0f> 0b 5a e9 aa fc ff ff 48 89 ef e8 28 9f 75 00 e9 17 fd ff ff 48 [ 28.101200][ T1] RSP: 0000:ffffc9000027f910 EFLAGS: 00010286 [ 28.108760][ T1] RAX: 0000000000000000 RBX: ffff88814be20070 RCX: 0000000000000000 [ 28.117095][ T1] RDX: ffff888019644040 RSI: ffffffff814cf096 RDI: 0000000000000001 [ 28.126618][ T1] RBP: ffff88814be20078 R08: 0000000000000001 R09: 0000000000000000 [ 28.135129][ T1] R10: 0000000000000001 R11: 0000000000000001 R12: ffff88814be20070 [ 28.143194][ T1] R13: ffffffff8a8c9240 R14: ffff888019644040 R15: 0000000000000000 [ 28.151661][ T1] ? __warn_printk+0x1a6/0x350 [ 28.156636][ T1] ? reiserfs_remount+0x1640/0x1640 [ 28.162549][ T1] generic_shutdown_super+0x1e4/0x3c0 [ 28.168079][ T1] ? reiserfs_remount+0x1640/0x1640 [ 28.173469][ T1] kill_block_super+0x3b/0x70 [ 28.178141][ T1] deactivate_locked_super+0xa6/0x180 [ 28.185001][ T1] mount_bdev+0x2a6/0x300 [ 28.189343][ T1] ? sget+0x610/0x610 [ 28.193358][ T1] ? vfs_parse_fs_param+0x3c0/0x3c0 [ 28.198655][ T1] ? cap_capable+0x1d8/0x240 [ 28.203381][ T1] ? reiserfs_kill_sb+0x1e0/0x1e0 [ 28.208422][ T1] legacy_get_tree+0x109/0x220 [ 28.213330][ T1] vfs_get_tree+0x8c/0x370 [ 28.217759][ T1] path_mount+0x1492/0x1ed0 [ 28.222264][ T1] ? kmem_cache_free+0x223/0x380 [ 28.227628][ T1] ? finish_automount+0xa40/0xa40 [ 28.232783][ T1] ? putname+0x101/0x140 [ 28.237039][ T1] init_mount+0xbf/0x110 [ 28.241283][ T1] ? nsfs_init+0xb0/0xb0 [ 28.245522][ T1] do_mount_root+0xdd/0x2c0 [ 28.250046][ T1] mount_root_generic+0x19a/0x460 [ 28.255065][ T1] ? init_rootfs+0x60/0x60 [ 28.259488][ T1] ? getname_kernel+0x21c/0x360 [ 28.264366][ T1] mount_root+0x241/0x480 [ 28.268693][ T1] ? kmem_cache_alloc+0x338/0x400 [ 28.273700][ T1] ? mount_root_generic+0x460/0x460 [ 28.278888][ T1] ? getname_kernel+0x21c/0x360 [ 28.283735][ T1] prepare_namespace+0xe3/0x3f0 [ 28.288575][ T1] ? mount_root+0x480/0x480 [ 28.293225][ T1] ? fput+0x30/0x1a0 [ 28.297134][ T1] kernel_init_freeable+0x703/0x8f0 [ 28.302361][ T1] ? rest_init+0x2b0/0x2b0 [ 28.306831][ T1] kernel_init+0x1c/0x2a0 [ 28.311182][ T1] ? rest_init+0x2b0/0x2b0 [ 28.315698][ T1] ret_from_fork+0x45/0x80 [ 28.320147][ T1] ? rest_init+0x2b0/0x2b0 [ 28.324661][ T1] ret_from_fork_asm+0x11/0x20 [ 28.329423][ T1] </TASK> [ 28.332714][ T1] Kernel Offset: disabled [ 28.337046][ T1] Rebooting in 86400 seconds.. syzkaller build log: go env (err=<nil>) GO111MODULE="auto" GOARCH="amd64" GOBIN="" GOCACHE="/syzkaller/.cache/go-build" GOENV="/syzkaller/.config/go/env" GOEXE="" GOEXPERIMENT="" GOFLAGS="" GOHOSTARCH="amd64" GOHOSTOS="linux" GOINSECURE="" GOMODCACHE="/syzkaller/jobs-2/linux/gopath/pkg/mod" GONOPROXY="" GONOSUMDB="" GOOS="linux" GOPATH="/syzkaller/jobs-2/linux/gopath" GOPRIVATE="" GOPROXY="https://proxy.golang.org,direct" GOROOT="/usr/local/go" GOSUMDB="sum.golang.org" GOTMPDIR="" GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64" GOVCS="" GOVERSION="go1.20.1" GCCGO="gccgo" GOAMD64="v1" AR="ar" CC="gcc" CXX="g++" CGO_ENABLED="1" GOMOD="/syzkaller/jobs-2/linux/gopath/src/github.com/google/syzkaller/go.mod" GOWORK="" CGO_CFLAGS="-O2 -g" CGO_CPPFLAGS="" CGO_CXXFLAGS="-O2 -g" CGO_FFLAGS="-O2 -g" CGO_LDFLAGS="-O2 -g" PKG_CONFIG="pkg-config" GOGCCFLAGS="-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build4053167018=/tmp/go-build -gno-record-gcc-switches" git status (err=<nil>) HEAD detached at 0b6a67ac4 nothing to commit, working tree clean tput: No value for $TERM and no -T specified tput: No value for $TERM and no -T specified Makefile:32: run command via tools/syz-env for best compatibility, see: Makefile:33: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env go list -f '{{.Stale}}' ./sys/syz-sysgen | grep -q false || go install ./sys/syz-sysgen make .descriptions tput: No value for $TERM and no -T specified tput: No value for $TERM and no -T specified bin/syz-sysgen touch .descriptions GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=0b6a67ac4b0dc26f43030c5edd01c9175f13b784 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20230913-073137'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-fuzzer github.com/google/syzkaller/syz-fuzzer GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=0b6a67ac4b0dc26f43030c5edd01c9175f13b784 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20230913-073137'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=0b6a67ac4b0dc26f43030c5edd01c9175f13b784 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20230913-073137'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-stress github.com/google/syzkaller/tools/syz-stress mkdir -p ./bin/linux_amd64 gcc -o ./bin/linux_amd64/syz-executor executor/executor.cc \ -m64 -O2 -pthread -Wall -Werror -Wparentheses -Wunused-const-variable -Wframe-larger-than=16384 -Wno-stringop-overflow -Wno-array-bounds -Wno-format-overflow -Wno-unused-but-set-variable -Wno-unused-command-line-argument -static-pie -fpermissive -w -DGOOS_linux=1 -DGOARCH_amd64=1 \ -DHOSTGOOS_linux=1 -DGIT_REVISION=\"0b6a67ac4b0dc26f43030c5edd01c9175f13b784\" Error text is too large and was truncated, full error text is at: https://syzkaller.appspot.com/x/error.txt?x=1688a642680000 Tested on: commit: 2cf0f715 Merge tag 'nfs-for-6.6-2' of git://git.linux-.. git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git kernel config: https://syzkaller.appspot.com/x/.config?x=710dc49bece494df dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 patch: https://syzkaller.appspot.com/x/patch.diff?x=1656035a680000 ^ permalink raw reply [flat|nested] 15+ messages in thread
[parent not found: <20230921111321.181-1-hdanton@sina.com>]
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock [not found] <20230921111321.181-1-hdanton@sina.com> @ 2023-09-21 11:33 ` syzbot 0 siblings, 0 replies; 15+ messages in thread From: syzbot @ 2023-09-21 11:33 UTC (permalink / raw) To: hdanton, linux-kernel, syzkaller-bugs Hello, syzbot has tested the proposed patch but the reproducer is still triggering an issue: possible deadlock in super_lock ====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc2-syzkaller-00018-g2cf0f7156238-dirty #0 Not tainted ------------------------------------------------------ syz-executor.2/5807 is trying to acquire lock: ffff88802862e0e0 (&type->s_umount_key#25){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] ffff88802862e0e0 (&type->s_umount_key#25){++++}-{3:3}, at: super_lock+0x23c/0x380 fs/super.c:117 but task is already holding lock: ffff8881484c3408 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] ffff8881484c3408 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x14e9/0x1ce0 block/ioctl.c:502 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&bdev->bd_holder_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 bdev_mark_dead+0x25/0x230 block/bdev.c:961 disk_force_media_change+0x51/0x80 block/disk-events.c:303 __loop_clr_fd+0x3ab/0x8f0 drivers/block/loop.c:1174 lo_release+0x188/0x1c0 drivers/block/loop.c:1743 blkdev_put_whole+0xa5/0xe0 block/bdev.c:663 blkdev_put+0x40f/0x8e0 block/bdev.c:898 blkdev_release+0x82/0xa0 block/fops.c:604 __fput+0x3f7/0xa70 fs/file_table.c:384 __fput_sync+0x47/0x50 fs/file_table.c:465 __do_sys_close fs/open.c:1572 [inline] __se_sys_close fs/open.c:1557 [inline] __x64_sys_close+0x87/0xf0 fs/open.c:1557 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #1 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 blkdev_put+0xb0/0x8e0 block/bdev.c:884 release_journal_dev fs/reiserfs/journal.c:2599 [inline] free_journal_ram+0x49f/0x650 fs/reiserfs/journal.c:1896 do_journal_release fs/reiserfs/journal.c:1960 [inline] journal_release+0x2a4/0x660 fs/reiserfs/journal.c:1971 reiserfs_put_super+0xe9/0x5c0 fs/reiserfs/super.c:616 generic_shutdown_super+0x161/0x3c0 fs/super.c:693 kill_block_super+0x3b/0x70 fs/super.c:1646 deactivate_locked_super+0x9a/0x170 fs/super.c:481 deactivate_super+0xde/0x100 fs/super.c:514 cleanup_mnt+0x222/0x3d0 fs/namespace.c:1254 task_work_run+0x14d/0x240 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&type->s_umount_key#25){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 down_read+0x9c/0x470 kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0x23c/0x380 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1431 [inline] fs_bdev_sync+0x94/0x1b0 fs/super.c:1466 blkdev_flushbuf block/ioctl.c:372 [inline] blkdev_common_ioctl+0x1550/0x1ce0 block/ioctl.c:502 blkdev_ioctl+0x249/0x770 block/ioctl.c:624 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &type->s_umount_key#25 --> &disk->open_mutex --> &bdev->bd_holder_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&bdev->bd_holder_lock); lock(&disk->open_mutex); lock(&bdev->bd_holder_lock); rlock(&type->s_umount_key#25); *** DEADLOCK *** 1 lock held by syz-executor.2/5807: #0: ffff8881484c3408 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] #0: ffff8881484c3408 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x14e9/0x1ce0 block/ioctl.c:502 stack backtrace: CPU: 1 PID: 5807 Comm: syz-executor.2 Not tainted 6.6.0-rc2-syzkaller-00018-g2cf0f7156238-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_noncircular+0x311/0x3f0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 down_read+0x9c/0x470 kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0x23c/0x380 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1431 [inline] fs_bdev_sync+0x94/0x1b0 fs/super.c:1466 blkdev_flushbuf block/ioctl.c:372 [inline] blkdev_common_ioctl+0x1550/0x1ce0 block/ioctl.c:502 blkdev_ioctl+0x249/0x770 block/ioctl.c:624 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fb8e707cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb8e7cf50c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fb8e719bf80 RCX: 00007fb8e707cae9 RDX: 0000000000000003 RSI: 0000000000001261 RDI: 0000000000000003 RBP: 00007fb8e70c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fb8e719bf80 R15: 00007ffd7864fa98 </TASK> Tested on: commit: 2cf0f715 Merge tag 'nfs-for-6.6-2' of git://git.linux-.. git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git console output: https://syzkaller.appspot.com/x/log.txt?x=13e90bf8680000 kernel config: https://syzkaller.appspot.com/x/.config?x=710dc49bece494df dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 patch: https://syzkaller.appspot.com/x/patch.diff?x=177cdcf2680000 ^ permalink raw reply [flat|nested] 15+ messages in thread
* [syzbot] [f2fs?] possible deadlock in super_lock @ 2023-09-03 22:30 syzbot 2023-09-20 9:13 ` [syzbot] [reiserfs?] " syzbot ` (3 more replies) 0 siblings, 4 replies; 15+ messages in thread From: syzbot @ 2023-09-03 22:30 UTC (permalink / raw) To: chao, jaegeuk, linux-f2fs-devel, linux-fsdevel, linux-kernel, syzkaller-bugs, terrelln Hello, syzbot found the following issue on: HEAD commit: 6c1b980a7e79 Merge tag 'dma-mapping-6.6-2023-08-29' of git.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13a9669fa80000 kernel config: https://syzkaller.appspot.com/x/.config?x=2212484c18930a61 dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/6e2281f5cb6b/disk-6c1b980a.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/5fc2481dcded/vmlinux-6c1b980a.xz kernel image: https://storage.googleapis.com/syzbot-assets/283bb76567da/bzImage-6c1b980a.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+062317ea1d0a6d5e29e7@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected 6.5.0-syzkaller-04808-g6c1b980a7e79 #0 Not tainted ------------------------------------------------------ syz-executor.4/22893 is trying to acquire lock: ffff888039b740e0 (&type->s_umount_key#25){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] ffff888039b740e0 (&type->s_umount_key#25){++++}-{3:3}, at: super_lock+0x23c/0x380 fs/super.c:117 but task is already holding lock: ffff88801e60ba88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:368 [inline] ffff88801e60ba88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x14e9/0x1ce0 block/ioctl.c:500 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&bdev->bd_holder_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 bdev_mark_dead+0x25/0x230 block/bdev.c:961 disk_force_media_change+0x51/0x80 block/disk-events.c:303 __loop_clr_fd+0x3ab/0x8f0 drivers/block/loop.c:1174 lo_release+0x188/0x1c0 drivers/block/loop.c:1743 blkdev_put_whole+0xa5/0xe0 block/bdev.c:663 blkdev_put+0x40f/0x8e0 block/bdev.c:898 kill_block_super+0x58/0x70 fs/super.c:1623 kill_f2fs_super+0x2b7/0x3d0 fs/f2fs/super.c:4879 deactivate_locked_super+0x9a/0x170 fs/super.c:481 deactivate_super+0xde/0x100 fs/super.c:514 cleanup_mnt+0x222/0x3d0 fs/namespace.c:1254 task_work_run+0x14d/0x240 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #1 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 blkdev_get_by_dev.part.0+0x4f0/0xb20 block/bdev.c:786 blkdev_get_by_dev+0x75/0x80 block/bdev.c:829 journal_init_dev fs/reiserfs/journal.c:2626 [inline] journal_init+0xbb8/0x64b0 fs/reiserfs/journal.c:2786 reiserfs_fill_super+0xcc6/0x3150 fs/reiserfs/super.c:2022 mount_bdev+0x1f3/0x2e0 fs/super.c:1603 legacy_get_tree+0x109/0x220 fs/fs_context.c:638 vfs_get_tree+0x8c/0x370 fs/super.c:1724 do_new_mount fs/namespace.c:3335 [inline] path_mount+0x1492/0x1ed0 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:3861 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&type->s_umount_key#25){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 down_read+0x9c/0x470 kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0x23c/0x380 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1387 [inline] fs_bdev_sync+0x94/0x1b0 fs/super.c:1422 blkdev_flushbuf block/ioctl.c:370 [inline] blkdev_common_ioctl+0x1550/0x1ce0 block/ioctl.c:500 blkdev_ioctl+0x249/0x770 block/ioctl.c:622 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &type->s_umount_key#25 --> &disk->open_mutex --> &bdev->bd_holder_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&bdev->bd_holder_lock); lock(&disk->open_mutex); lock(&bdev->bd_holder_lock); rlock(&type->s_umount_key#25); *** DEADLOCK *** 1 lock held by syz-executor.4/22893: #0: ffff88801e60ba88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:368 [inline] #0: ffff88801e60ba88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x14e9/0x1ce0 block/ioctl.c:500 stack backtrace: CPU: 1 PID: 22893 Comm: syz-executor.4 Not tainted 6.5.0-syzkaller-04808-g6c1b980a7e79 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_noncircular+0x311/0x3f0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 down_read+0x9c/0x470 kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0x23c/0x380 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1387 [inline] fs_bdev_sync+0x94/0x1b0 fs/super.c:1422 blkdev_flushbuf block/ioctl.c:370 [inline] blkdev_common_ioctl+0x1550/0x1ce0 block/ioctl.c:500 blkdev_ioctl+0x249/0x770 block/ioctl.c:622 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f6f9f67cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6fa03670c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f6f9f79bf80 RCX: 00007f6f9f67cae9 RDX: ffffffffffffffff RSI: 0000000000001261 RDI: 0000000000000003 RBP: 00007f6f9f6c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f6f9f79bf80 R15: 00007ffc6e219ec8 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup ^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock 2023-09-03 22:30 [syzbot] [f2fs?] " syzbot @ 2023-09-20 9:13 ` syzbot 2023-10-08 15:14 ` syzbot ` (2 subsequent siblings) 3 siblings, 0 replies; 15+ messages in thread From: syzbot @ 2023-09-20 9:13 UTC (permalink / raw) To: chao, jaegeuk, linux-f2fs-devel, linux-fsdevel, linux-kernel, reiserfs-devel, syzkaller-bugs, terrelln syzbot has found a reproducer for the following issue on: HEAD commit: 2cf0f7156238 Merge tag 'nfs-for-6.6-2' of git://git.linux-.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=12780282680000 kernel config: https://syzkaller.appspot.com/x/.config?x=710dc49bece494df dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=107e9518680000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/f48f4ed701b8/disk-2cf0f715.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/5b8491e29a2d/vmlinux-2cf0f715.xz kernel image: https://storage.googleapis.com/syzbot-assets/90faa04d6558/bzImage-2cf0f715.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/c98194587df7/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+062317ea1d0a6d5e29e7@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc2-syzkaller-00018-g2cf0f7156238 #0 Not tainted ------------------------------------------------------ syz-executor.0/8792 is trying to acquire lock: ffff88807993a0e0 (&type->s_umount_key#25){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] ffff88807993a0e0 (&type->s_umount_key#25){++++}-{3:3}, at: super_lock+0x23c/0x380 fs/super.c:117 but task is already holding lock: ffff888148439388 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] ffff888148439388 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x14e9/0x1ce0 block/ioctl.c:502 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&bdev->bd_holder_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 bdev_mark_dead+0x25/0x230 block/bdev.c:961 disk_force_media_change+0x51/0x80 block/disk-events.c:303 __loop_clr_fd+0x3ab/0x8f0 drivers/block/loop.c:1174 lo_release+0x188/0x1c0 drivers/block/loop.c:1743 blkdev_put_whole+0xa5/0xe0 block/bdev.c:663 blkdev_put+0x40f/0x8e0 block/bdev.c:898 kill_block_super+0x58/0x70 fs/super.c:1649 deactivate_locked_super+0x9a/0x170 fs/super.c:481 deactivate_super+0xde/0x100 fs/super.c:514 cleanup_mnt+0x222/0x3d0 fs/namespace.c:1254 task_work_run+0x14d/0x240 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #1 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 blkdev_get_by_dev.part.0+0x4f0/0xb20 block/bdev.c:786 blkdev_get_by_dev+0x75/0x80 block/bdev.c:829 journal_init_dev fs/reiserfs/journal.c:2626 [inline] journal_init+0xbb8/0x64b0 fs/reiserfs/journal.c:2786 reiserfs_fill_super+0xcc6/0x3150 fs/reiserfs/super.c:2022 mount_bdev+0x1f3/0x2e0 fs/super.c:1629 legacy_get_tree+0x109/0x220 fs/fs_context.c:638 vfs_get_tree+0x8c/0x370 fs/super.c:1750 do_new_mount fs/namespace.c:3335 [inline] path_mount+0x1492/0x1ed0 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __x64_sys_mount+0x293/0x310 fs/namespace.c:3861 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&type->s_umount_key#25){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 down_read+0x9c/0x470 kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0x23c/0x380 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1431 [inline] fs_bdev_sync+0x94/0x1b0 fs/super.c:1466 blkdev_flushbuf block/ioctl.c:372 [inline] blkdev_common_ioctl+0x1550/0x1ce0 block/ioctl.c:502 blkdev_ioctl+0x249/0x770 block/ioctl.c:624 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &type->s_umount_key#25 --> &disk->open_mutex --> &bdev->bd_holder_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&bdev->bd_holder_lock); lock(&disk->open_mutex); lock(&bdev->bd_holder_lock); rlock(&type->s_umount_key#25); *** DEADLOCK *** 1 lock held by syz-executor.0/8792: #0: ffff888148439388 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] #0: ffff888148439388 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x14e9/0x1ce0 block/ioctl.c:502 stack backtrace: CPU: 0 PID: 8792 Comm: syz-executor.0 Not tainted 6.6.0-rc2-syzkaller-00018-g2cf0f7156238 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_noncircular+0x311/0x3f0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 down_read+0x9c/0x470 kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0x23c/0x380 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1431 [inline] fs_bdev_sync+0x94/0x1b0 fs/super.c:1466 blkdev_flushbuf block/ioctl.c:372 [inline] blkdev_common_ioctl+0x1550/0x1ce0 block/ioctl.c:502 blkdev_ioctl+0x249/0x770 block/ioctl.c:624 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f18ae67cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f18af4830c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f18ae79bf80 RCX: 00007f18ae67cae9 RDX: 0000000000000003 RSI: 0000000000001261 RDI: 0000000000000003 RBP: 00007f18ae6c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f18ae79bf80 R15: 00007ffc4185a478 </TASK> --- If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. ^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock 2023-09-03 22:30 [syzbot] [f2fs?] " syzbot 2023-09-20 9:13 ` [syzbot] [reiserfs?] " syzbot @ 2023-10-08 15:14 ` syzbot 2023-10-09 2:05 ` syzbot 2023-12-24 16:40 ` syzbot 3 siblings, 0 replies; 15+ messages in thread From: syzbot @ 2023-10-08 15:14 UTC (permalink / raw) To: chao, hdanton, jaegeuk, linux-f2fs-devel, linux-fsdevel, linux-kernel, reiserfs-devel, syzkaller-bugs, terrelln syzbot has found a reproducer for the following issue on: HEAD commit: 19af4a4ed414 Merge branch 'for-next/core', remote-tracking.. git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci console output: https://syzkaller.appspot.com/x/log.txt?x=1627a911680000 kernel config: https://syzkaller.appspot.com/x/.config?x=80eedef55cd21fa4 dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: arm64 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13deb1c9680000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1006a759680000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/702d996331e0/disk-19af4a4e.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/2a48ce0aeb32/vmlinux-19af4a4e.xz kernel image: https://storage.googleapis.com/syzbot-assets/332eb4a803d2/Image-19af4a4e.gz.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/97d89134ed25/mount_2.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+062317ea1d0a6d5e29e7@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc4-syzkaller-g19af4a4ed414 #0 Not tainted ------------------------------------------------------ syz-executor254/6025 is trying to acquire lock: ffff0000db54a0e0 (&type->s_umount_key#25){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] ffff0000db54a0e0 (&type->s_umount_key#25){++++}-{3:3}, at: super_lock+0x160/0x328 fs/super.c:117 but task is already holding lock: ffff0000c1540c88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] ffff0000c1540c88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x7fc/0x2884 block/ioctl.c:502 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&bdev->bd_holder_lock){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 bd_finish_claiming+0x218/0x3dc block/bdev.c:566 blkdev_get_by_dev+0x3f4/0x55c block/bdev.c:799 setup_bdev_super+0x68/0x51c fs/super.c:1484 mount_bdev+0x1a0/0x2b4 fs/super.c:1626 get_super_block+0x44/0x58 fs/reiserfs/super.c:2601 legacy_get_tree+0xd4/0x16c fs/fs_context.c:638 vfs_get_tree+0x90/0x288 fs/super.c:1750 do_new_mount+0x25c/0x8c8 fs/namespace.c:3335 path_mount+0x590/0xe04 fs/namespace.c:3662 init_mount+0xe4/0x144 fs/init.c:25 do_mount_root+0x104/0x3e4 init/do_mounts.c:166 mount_root_generic+0x1f0/0x594 init/do_mounts.c:205 mount_block_root+0x6c/0x7c init/do_mounts.c:378 mount_root+0xb4/0xe4 init/do_mounts.c:405 prepare_namespace+0xdc/0x11c init/do_mounts.c:489 kernel_init_freeable+0x35c/0x474 init/main.c:1560 kernel_init+0x24/0x29c init/main.c:1437 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:857 -> #2 (bdev_lock ){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 bd_finish_claiming+0x84/0x3dc block/bdev.c:557 blkdev_get_by_dev+0x3f4/0x55c block/bdev.c:799 setup_bdev_super+0x68/0x51c fs/super.c:1484 mount_bdev+0x1a0/0x2b4 fs/super.c:1626 get_super_block+0x44/0x58 fs/reiserfs/super.c:2601 legacy_get_tree+0xd4/0x16c fs/fs_context.c:638 vfs_get_tree+0x90/0x288 fs/super.c:1750 do_new_mount+0x25c/0x8c8 fs/namespace.c:3335 path_mount+0x590/0xe04 fs/namespace.c:3662 init_mount+0xe4/0x144 fs/init.c:25 do_mount_root+0x104/0x3e4 init/do_mounts.c:166 mount_root_generic+0x1f0/0x594 init/do_mounts.c:205 mount_block_root+0x6c/0x7c init/do_mounts.c:378 mount_root+0xb4/0xe4 init/do_mounts.c:405 prepare_namespace+0xdc/0x11c init/do_mounts.c:489 kernel_init_freeable+0x35c/0x474 init/main.c:1560 kernel_init+0x24/0x29c init/main.c:1437 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:857 -> #1 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 journal_init_dev fs/reiserfs/journal.c:2626 [inline] journal_init+0xa60/0x1e44 fs/reiserfs/journal.c:2786 reiserfs_fill_super+0xd50/0x2028 fs/reiserfs/super.c:2022 mount_bdev+0x1e8/0x2b4 fs/super.c:1629 get_super_block+0x44/0x58 fs/reiserfs/super.c:2601 legacy_get_tree+0xd4/0x16c fs/fs_context.c:638 vfs_get_tree+0x90/0x288 fs/super.c:1750 do_new_mount+0x25c/0x8c8 fs/namespace.c:3335 path_mount+0x590/0xe04 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3861 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 -> #0 (&type->s_umount_key#25){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x3370/0x75e8 kernel/locking/lockdep.c:5136 lock_acquire+0x23c/0x71c kernel/locking/lockdep.c:5753 down_read+0x58/0x2fc kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0x160/0x328 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1431 [inline] fs_bdev_sync+0xa4/0x168 fs/super.c:1466 blkdev_flushbuf block/ioctl.c:372 [inline] blkdev_common_ioctl+0x848/0x2884 block/ioctl.c:502 blkdev_ioctl+0x35c/0xae4 block/ioctl.c:624 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:857 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 other info that might help us debug this: Chain exists of: &type->s_umount_key#25 --> bdev_lock --> &bdev->bd_holder_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&bdev->bd_holder_lock); lock(bdev_lock); lock(&bdev->bd_holder_lock); rlock(&type->s_umount_key#25); *** DEADLOCK *** 1 lock held by syz-executor254/6025: #0: ffff0000c1540c88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] #0: ffff0000c1540c88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x7fc/0x2884 block/ioctl.c:502 stack backtrace: CPU: 0 PID: 6025 Comm: syz-executor254 Not tainted 6.6.0-rc4-syzkaller-g19af4a4ed414 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233 show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 dump_stack+0x1c/0x28 lib/dump_stack.c:113 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2060 check_noncircular+0x310/0x404 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x3370/0x75e8 kernel/locking/lockdep.c:5136 lock_acquire+0x23c/0x71c kernel/locking/lockdep.c:5753 down_read+0x58/0x2fc kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0x160/0x328 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1431 [inline] fs_bdev_sync+0xa4/0x168 fs/super.c:1466 blkdev_flushbuf block/ioctl.c:372 [inline] blkdev_common_ioctl+0x848/0x2884 block/ioctl.c:502 blkdev_ioctl+0x35c/0xae4 block/ioctl.c:624 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:857 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 --- If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. ^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock 2023-09-03 22:30 [syzbot] [f2fs?] " syzbot 2023-09-20 9:13 ` [syzbot] [reiserfs?] " syzbot 2023-10-08 15:14 ` syzbot @ 2023-10-09 2:05 ` syzbot 2023-10-09 12:37 ` Christian Brauner 2023-12-24 16:40 ` syzbot 3 siblings, 1 reply; 15+ messages in thread From: syzbot @ 2023-10-09 2:05 UTC (permalink / raw) To: axboe, brauner, chao, daniel.vetter, hdanton, jack, jaegeuk, jinpu.wang, linux-f2fs-devel, linux-fsdevel, linux-kernel, mairacanal, mcanal, reiserfs-devel, syzkaller-bugs, terrelln, willy, yukuai3 syzbot has bisected this issue to: commit 7908632f2927b65f7486ae6b67c24071666ba43f Author: Maíra Canal <mcanal@igalia.com> Date: Thu Sep 14 10:19:02 2023 +0000 Revert "drm/vkms: Fix race-condition between the hrtimer and the atomic commit" bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=17fc0565680000 start commit: 2cf0f7156238 Merge tag 'nfs-for-6.6-2' of git://git.linux-.. git tree: upstream final oops: https://syzkaller.appspot.com/x/report.txt?x=14020565680000 console output: https://syzkaller.appspot.com/x/log.txt?x=10020565680000 kernel config: https://syzkaller.appspot.com/x/.config?x=710dc49bece494df dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=107e9518680000 Reported-by: syzbot+062317ea1d0a6d5e29e7@syzkaller.appspotmail.com Fixes: 7908632f2927 ("Revert "drm/vkms: Fix race-condition between the hrtimer and the atomic commit"") For information about bisection process see: https://goo.gl/tpsmEJ#bisection ^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock 2023-10-09 2:05 ` syzbot @ 2023-10-09 12:37 ` Christian Brauner 2023-10-09 14:19 ` syzbot 0 siblings, 1 reply; 15+ messages in thread From: Christian Brauner @ 2023-10-09 12:37 UTC (permalink / raw) To: syzbot Cc: axboe, chao, daniel.vetter, hdanton, jack, jaegeuk, jinpu.wang, linux-f2fs-devel, linux-fsdevel, linux-kernel, mairacanal, mcanal, reiserfs-devel, syzkaller-bugs, terrelln, willy, yukuai3 On Sun, Oct 08, 2023 at 07:05:32PM -0700, syzbot wrote: > syzbot has bisected this issue to: > > commit 7908632f2927b65f7486ae6b67c24071666ba43f > Author: Maíra Canal <mcanal@igalia.com> > Date: Thu Sep 14 10:19:02 2023 +0000 > > Revert "drm/vkms: Fix race-condition between the hrtimer and the atomic commit" > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=17fc0565680000 > start commit: 2cf0f7156238 Merge tag 'nfs-for-6.6-2' of git://git.linux-.. > git tree: upstream > final oops: https://syzkaller.appspot.com/x/report.txt?x=14020565680000 > console output: https://syzkaller.appspot.com/x/log.txt?x=10020565680000 > kernel config: https://syzkaller.appspot.com/x/.config?x=710dc49bece494df > dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=107e9518680000 > > Reported-by: syzbot+062317ea1d0a6d5e29e7@syzkaller.appspotmail.com > Fixes: 7908632f2927 ("Revert "drm/vkms: Fix race-condition between the hrtimer and the atomic commit"") > > For information about bisection process see: https://goo.gl/tpsmEJ#bisection The bisect is obviously bogus. I haven't seend that bug report before otherwise I would've already fixed this way earlier: #syz test: https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git b4/vfs-fixes-reiserfs ^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock 2023-10-09 12:37 ` Christian Brauner @ 2023-10-09 14:19 ` syzbot 0 siblings, 0 replies; 15+ messages in thread From: syzbot @ 2023-10-09 14:19 UTC (permalink / raw) To: axboe, brauner, chao, daniel.vetter, hdanton, jack, jaegeuk, jinpu.wang, linux-f2fs-devel, linux-fsdevel, linux-kernel, mairacanal, mcanal, reiserfs-devel, syzkaller-bugs, terrelln, willy, yukuai3 Hello, syzbot has tested the proposed patch but the reproducer is still triggering an issue: INFO: task hung in blkdev_put INFO: task syz-executor.1:6676 blocked for more than 143 seconds. Not tainted 6.6.0-rc5-syzkaller-gb6ab131813c2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:0 pid:6676 ppid:6383 flags:0x00000005 Call trace: __switch_to+0x320/0x754 arch/arm64/kernel/process.c:556 context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1364/0x23b4 kernel/sched/core.c:6695 schedule+0xc4/0x170 kernel/sched/core.c:6771 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6830 __mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 blkdev_put+0xec/0x740 block/bdev.c:884 blkdev_release+0x84/0x9c block/fops.c:604 __fput+0x324/0x7f8 fs/file_table.c:384 __fput_sync+0x60/0x9c fs/file_table.c:465 __do_sys_close fs/open.c:1572 [inline] __se_sys_close fs/open.c:1557 [inline] __arm64_sys_close+0x150/0x1e0 fs/open.c:1557 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 INFO: task syz-executor.2:6678 blocked for more than 143 seconds. Not tainted 6.6.0-rc5-syzkaller-gb6ab131813c2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:0 pid:6678 ppid:6377 flags:0x00000005 Call trace: __switch_to+0x320/0x754 arch/arm64/kernel/process.c:556 context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1364/0x23b4 kernel/sched/core.c:6695 schedule+0xc4/0x170 kernel/sched/core.c:6771 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6830 __mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 blkdev_put+0xec/0x740 block/bdev.c:884 blkdev_release+0x84/0x9c block/fops.c:604 __fput+0x324/0x7f8 fs/file_table.c:384 __fput_sync+0x60/0x9c fs/file_table.c:465 __do_sys_close fs/open.c:1572 [inline] __se_sys_close fs/open.c:1557 [inline] __arm64_sys_close+0x150/0x1e0 fs/open.c:1557 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 INFO: task syz-executor.0:6682 blocked for more than 143 seconds. Not tainted 6.6.0-rc5-syzkaller-gb6ab131813c2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:0 pid:6682 ppid:6389 flags:0x0000000d Call trace: __switch_to+0x320/0x754 arch/arm64/kernel/process.c:556 context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1364/0x23b4 kernel/sched/core.c:6695 schedule+0xc4/0x170 kernel/sched/core.c:6771 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6830 __mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 bd_finish_claiming+0x218/0x3dc block/bdev.c:566 blkdev_get_by_dev+0x3f4/0x55c block/bdev.c:799 journal_init_dev fs/reiserfs/journal.c:2616 [inline] journal_init+0xb08/0x1e68 fs/reiserfs/journal.c:2783 reiserfs_fill_super+0xd58/0x2058 fs/reiserfs/super.c:2029 mount_bdev+0x1e8/0x2b4 fs/super.c:1629 get_super_block+0x44/0x58 fs/reiserfs/super.c:2605 legacy_get_tree+0xd4/0x16c fs/fs_context.c:638 vfs_get_tree+0x90/0x288 fs/super.c:1750 do_new_mount+0x25c/0x8c8 fs/namespace.c:3335 path_mount+0x590/0xe04 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3861 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 INFO: task syz-executor.3:6690 blocked for more than 143 seconds. Not tainted 6.6.0-rc5-syzkaller-gb6ab131813c2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:0 pid:6690 ppid:6373 flags:0x0000000d Call trace: __switch_to+0x320/0x754 arch/arm64/kernel/process.c:556 context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1364/0x23b4 kernel/sched/core.c:6695 schedule+0xc4/0x170 kernel/sched/core.c:6771 super_lock+0x23c/0x328 fs/super.c:134 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1431 [inline] fs_bdev_sync+0xa4/0x168 fs/super.c:1466 blkdev_flushbuf block/ioctl.c:372 [inline] blkdev_common_ioctl+0x848/0x2884 block/ioctl.c:502 blkdev_ioctl+0x35c/0xae4 block/ioctl.c:624 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:857 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 INFO: task syz-executor.3:6695 blocked for more than 143 seconds. Not tainted 6.6.0-rc5-syzkaller-gb6ab131813c2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:0 pid:6695 ppid:6373 flags:0x00000005 Call trace: __switch_to+0x320/0x754 arch/arm64/kernel/process.c:556 context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1364/0x23b4 kernel/sched/core.c:6695 schedule+0xc4/0x170 kernel/sched/core.c:6771 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6830 __mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 loop_configure+0x15c/0xfd4 drivers/block/loop.c:1018 lo_ioctl+0xc70/0x1d04 blkdev_ioctl+0x3e4/0xae4 block/ioctl.c:630 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:857 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 INFO: task syz-executor.5:6696 blocked for more than 143 seconds. Not tainted 6.6.0-rc5-syzkaller-gb6ab131813c2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:0 pid:6696 ppid:6381 flags:0x00000005 Call trace: __switch_to+0x320/0x754 arch/arm64/kernel/process.c:556 context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1364/0x23b4 kernel/sched/core.c:6695 schedule+0xc4/0x170 kernel/sched/core.c:6771 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6830 __mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 blkdev_open+0x128/0x2b0 block/fops.c:589 do_dentry_open+0x6fc/0x118c fs/open.c:929 vfs_open+0x7c/0x90 fs/open.c:1063 do_open fs/namei.c:3639 [inline] path_openat+0x1f2c/0x27f8 fs/namei.c:3796 do_filp_open+0x1bc/0x3cc fs/namei.c:3823 do_sys_openat2+0x124/0x1b8 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __arm64_sys_openat+0x1f0/0x240 fs/open.c:1448 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 INFO: task syz-executor.5:6703 blocked for more than 143 seconds. Not tainted 6.6.0-rc5-syzkaller-gb6ab131813c2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:0 pid:6703 ppid:6381 flags:0x00000005 Call trace: __switch_to+0x320/0x754 arch/arm64/kernel/process.c:556 context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1364/0x23b4 kernel/sched/core.c:6695 schedule+0xc4/0x170 kernel/sched/core.c:6771 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6830 __mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 loop_configure+0x15c/0xfd4 drivers/block/loop.c:1018 lo_ioctl+0xc70/0x1d04 blkdev_ioctl+0x3e4/0xae4 block/ioctl.c:630 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:857 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 INFO: task syz-executor.4:6698 blocked for more than 143 seconds. Not tainted 6.6.0-rc5-syzkaller-gb6ab131813c2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:0 pid:6698 ppid:6384 flags:0x00000005 Call trace: __switch_to+0x320/0x754 arch/arm64/kernel/process.c:556 context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1364/0x23b4 kernel/sched/core.c:6695 schedule+0xc4/0x170 kernel/sched/core.c:6771 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6830 __mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 blkdev_open+0x128/0x2b0 block/fops.c:589 do_dentry_open+0x6fc/0x118c fs/open.c:929 vfs_open+0x7c/0x90 fs/open.c:1063 do_open fs/namei.c:3639 [inline] path_openat+0x1f2c/0x27f8 fs/namei.c:3796 do_filp_open+0x1bc/0x3cc fs/namei.c:3823 do_sys_openat2+0x124/0x1b8 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __arm64_sys_openat+0x1f0/0x240 fs/open.c:1448 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 INFO: task syz-executor.4:6704 blocked for more than 143 seconds. Not tainted 6.6.0-rc5-syzkaller-gb6ab131813c2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:0 pid:6704 ppid:6384 flags:0x00000005 Call trace: __switch_to+0x320/0x754 arch/arm64/kernel/process.c:556 context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1364/0x23b4 kernel/sched/core.c:6695 schedule+0xc4/0x170 kernel/sched/core.c:6771 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6830 __mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 loop_configure+0x15c/0xfd4 drivers/block/loop.c:1018 lo_ioctl+0xc70/0x1d04 blkdev_ioctl+0x3e4/0xae4 block/ioctl.c:630 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:857 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffff80008e3739c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:302 2 locks held by kworker/u4:6/235: 2 locks held by getty/5770: #0: ffff0000d6cf20a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff8000959f02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1214 drivers/tty/n_tty.c:2206 1 lock held by syz-executor.1/6676: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xec/0x740 block/bdev.c:884 1 lock held by syz-executor.2/6678: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xec/0x740 block/bdev.c:884 3 locks held by syz-executor.0/6682: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 #1: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_finish_claiming+0x84/0x3dc block/bdev.c:557 #2: ffff0000c1543a88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: bd_finish_claiming+0x218/0x3dc block/bdev.c:566 1 lock held by syz-executor.3/6690: #0: ffff0000c1543a88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] #0: ffff0000c1543a88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x7fc/0x2884 block/ioctl.c:502 1 lock held by syz-executor.3/6695: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 1 lock held by syz-executor.5/6696: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.5/6703: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 1 lock held by syz-executor.4/6698: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.4/6704: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 1 lock held by syz-executor.0/6872: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.1/6939: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.1/6940: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 1 lock held by syz-executor.2/6956: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.2/6957: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 1 lock held by syz-executor.5/6959: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.5/6960: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 1 lock held by syz-executor.3/6976: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.3/6977: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 1 lock held by syz-executor.4/6979: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.4/6980: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 1 lock held by syz-executor.1/6999: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.1/7000: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 1 lock held by syz-executor.2/7054: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.2/7055: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 1 lock held by syz-executor.5/7067: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.5/7068: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 1 lock held by syz-executor.3/7075: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.3/7078: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 1 lock held by syz-executor.4/7083: #0: ffff0000c9ce34c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 1 lock held by syz-executor.4/7084: #0: ffff80008e1748a8 (bdev_lock){+.+.}-{3:3}, at: bd_prepare_to_claim+0x1a4/0x49c block/bdev.c:508 ============================================= Tested on: commit: b6ab1318 reiserfs: fix journal device opening git tree: https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git b4/vfs-fixes-reiserfs console output: https://syzkaller.appspot.com/x/log.txt?x=125bdcde680000 kernel config: https://syzkaller.appspot.com/x/.config?x=1b8c825e0d5f3f72 dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: arm64 Note: no patches were applied. ^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock 2023-09-03 22:30 [syzbot] [f2fs?] " syzbot ` (2 preceding siblings ...) 2023-10-09 2:05 ` syzbot @ 2023-12-24 16:40 ` syzbot 2023-12-28 10:50 ` Christian Brauner 3 siblings, 1 reply; 15+ messages in thread From: syzbot @ 2023-12-24 16:40 UTC (permalink / raw) To: axboe, brauner, chao, christian, daniel.vetter, hch, hdanton, jack, jaegeuk, jinpu.wang, linux-f2fs-devel, linux-fsdevel, linux-kernel, mairacanal, mcanal, reiserfs-devel, syzkaller-bugs, terrelln, willy, yukuai3 syzbot suspects this issue was fixed by commit: commit fd1464105cb37a3b50a72c1d2902e97a71950af8 Author: Jan Kara <jack@suse.cz> Date: Wed Oct 18 15:29:24 2023 +0000 fs: Avoid grabbing sb->s_umount under bdev->bd_holder_lock bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14639595e80000 start commit: 2cf0f7156238 Merge tag 'nfs-for-6.6-2' of git://git.linux-.. git tree: upstream kernel config: https://syzkaller.appspot.com/x/.config?x=710dc49bece494df dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=107e9518680000 If the result looks correct, please mark the issue as fixed by replying with: #syz fix: fs: Avoid grabbing sb->s_umount under bdev->bd_holder_lock For information about bisection process see: https://goo.gl/tpsmEJ#bisection ^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock 2023-12-24 16:40 ` syzbot @ 2023-12-28 10:50 ` Christian Brauner 2024-01-02 12:14 ` Jan Kara 0 siblings, 1 reply; 15+ messages in thread From: Christian Brauner @ 2023-12-28 10:50 UTC (permalink / raw) To: syzbot Cc: axboe, chao, christian, daniel.vetter, hch, hdanton, jack, jaegeuk, jinpu.wang, linux-f2fs-devel, linux-fsdevel, linux-kernel, mairacanal, mcanal, reiserfs-devel, syzkaller-bugs, terrelln, willy, yukuai3 On Sun, Dec 24, 2023 at 08:40:05AM -0800, syzbot wrote: > syzbot suspects this issue was fixed by commit: > > commit fd1464105cb37a3b50a72c1d2902e97a71950af8 > Author: Jan Kara <jack@suse.cz> > Date: Wed Oct 18 15:29:24 2023 +0000 > > fs: Avoid grabbing sb->s_umount under bdev->bd_holder_lock > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14639595e80000 > start commit: 2cf0f7156238 Merge tag 'nfs-for-6.6-2' of git://git.linux-.. > git tree: upstream > kernel config: https://syzkaller.appspot.com/x/.config?x=710dc49bece494df > dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=107e9518680000 > > If the result looks correct, please mark the issue as fixed by replying with: > > #syz fix: fs: Avoid grabbing sb->s_umount under bdev->bd_holder_lock > > For information about bisection process see: https://goo.gl/tpsmEJ#bisection Fwiw, this was always a false-positive. But we also reworked the locking that even the false-positive cannot be triggered anymore. So yay! ^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [syzbot] [reiserfs?] possible deadlock in super_lock 2023-12-28 10:50 ` Christian Brauner @ 2024-01-02 12:14 ` Jan Kara 0 siblings, 0 replies; 15+ messages in thread From: Jan Kara @ 2024-01-02 12:14 UTC (permalink / raw) To: syzbot Cc: Christian Brauner, axboe, chao, christian, daniel.vetter, hch, hdanton, jack, jaegeuk, jinpu.wang, linux-f2fs-devel, linux-fsdevel, linux-kernel, mairacanal, mcanal, reiserfs-devel, syzkaller-bugs, terrelln, willy, yukuai3 On Thu 28-12-23 11:50:32, Christian Brauner wrote: > On Sun, Dec 24, 2023 at 08:40:05AM -0800, syzbot wrote: > > syzbot suspects this issue was fixed by commit: > > > > commit fd1464105cb37a3b50a72c1d2902e97a71950af8 > > Author: Jan Kara <jack@suse.cz> > > Date: Wed Oct 18 15:29:24 2023 +0000 > > > > fs: Avoid grabbing sb->s_umount under bdev->bd_holder_lock > > > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14639595e80000 > > start commit: 2cf0f7156238 Merge tag 'nfs-for-6.6-2' of git://git.linux-.. > > git tree: upstream > > kernel config: https://syzkaller.appspot.com/x/.config?x=710dc49bece494df > > dashboard link: https://syzkaller.appspot.com/bug?extid=062317ea1d0a6d5e29e7 > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=107e9518680000 > > > > If the result looks correct, please mark the issue as fixed by replying with: > > > > #syz fix: fs: Avoid grabbing sb->s_umount under bdev->bd_holder_lock > > > > For information about bisection process see: https://goo.gl/tpsmEJ#bisection > > Fwiw, this was always a false-positive. But we also reworked the locking > that even the false-positive cannot be triggered anymore. So yay! Yup, nice. I think you need to start the line with syz command so: #syz fix: fs: Avoid grabbing sb->s_umount under bdev->bd_holder_lock Honza -- Jan Kara <jack@suse.com> SUSE Labs, CR ^ permalink raw reply [flat|nested] 15+ messages in thread
end of thread, other threads:[~2024-01-02 12:15 UTC | newest] Thread overview: 15+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- [not found] <20230923040320.1384-1-hdanton@sina.com> 2023-09-23 4:26 ` [syzbot] [reiserfs?] possible deadlock in super_lock syzbot [not found] <20231010111343.2257-1-hdanton@sina.com> 2023-10-10 11:49 ` syzbot [not found] <20231009112906.2143-1-hdanton@sina.com> 2023-10-09 14:01 ` syzbot [not found] <20230923024635.1249-1-hdanton@sina.com> 2023-09-23 3:02 ` syzbot [not found] <20230923010437.297-1-hdanton@sina.com> 2023-09-23 1:14 ` syzbot [not found] <20230922124125.240-1-hdanton@sina.com> 2023-09-22 13:11 ` syzbot [not found] <20230921111321.181-1-hdanton@sina.com> 2023-09-21 11:33 ` syzbot 2023-09-03 22:30 [syzbot] [f2fs?] " syzbot 2023-09-20 9:13 ` [syzbot] [reiserfs?] " syzbot 2023-10-08 15:14 ` syzbot 2023-10-09 2:05 ` syzbot 2023-10-09 12:37 ` Christian Brauner 2023-10-09 14:19 ` syzbot 2023-12-24 16:40 ` syzbot 2023-12-28 10:50 ` Christian Brauner 2024-01-02 12:14 ` Jan Kara
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