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BUG: soft lockup in sys_sendmsg (2)

Status: upstream: reported C repro on 2025/06/05 02:15
Subsystems: block
[Documentation on labels]
Reported-by: syzbot+4032319a6a907f69e985@syzkaller.appspotmail.com
First crash: 334d, last: 1d00h
Cause bisection: failed (error log, bisect log)
  
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [scsi?] [mm?] [block?] BUG: soft lockup in sys_sendmsg (2) 1 (4) 2025/10/18 05:53
▶ ▼ Similar bugs (13)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-6-1 BUG: soft lockup in sys_sendmsg origin:upstream 1 C 3 689d 717d 0/2 upstream: reported C repro on 2024/04/09 06:46
linux-6.1 BUG: soft lockup in sys_sendmsg 1 2 1018d 1024d 0/3 auto-obsoleted due to no activity on 2023/09/20 17:26
android-5-10 BUG: soft lockup in sys_sendmsg 1 C error 61 38d 734d 0/2 upstream: reported C repro on 2024/03/22 10:41
upstream BUG: soft lockup in sys_sendmsg tipc batman 1 C 3 732d 773d 25/29 fixed on 2024/05/22 23:36
android-5-15 BUG: soft lockup in sys_sendmsg origin:upstream 1 C error 13 561d 734d 0/2 upstream: reported C repro on 2024/03/22 10:44
linux-5.15 INFO: rcu detected stall in sys_sendmsg origin:upstream 1 C error 38 1d14h 737d 0/3 upstream: reported C repro on 2024/03/19 21:37
linux-6.1 BUG: soft lockup in sys_sendmsg (2) origin:upstream 1 C done 1 719d 719d 3/3 fixed on 2024/05/15 09:17
linux-6.1 INFO: rcu detected stall in sendmsg (5) 1 syz 16 8d08h 277d 0/3 upstream: reported syz repro on 2025/06/23 07:43
linux-6.6 INFO: rcu detected stall in sendmsg 1 7 4d13h 238d 0/2 upstream: reported on 2025/07/31 17:16
linux-6.1 INFO: rcu detected stall in sys_sendmsg 1 6 544d 631d 0/3 auto-obsoleted due to no activity on 2025/01/06 11:24
upstream INFO: rcu detected stall in sys_sendmsg (2) cgroups mm 1 5 2304d 2306d 0/29 closed as invalid on 2019/12/04 14:14
upstream INFO: rcu detected stall in sys_sendmsg (3) kernel 1 1 2270d 2270d 0/29 closed as invalid on 2020/01/08 05:33
upstream INFO: rcu detected stall in sys_sendmsg net 1 C done 2 2386d 2386d 13/29 fixed on 2019/10/09 10:54
▶ ▼ Last patch testing requests (4)
Created Duration User Patch Repo Result
2026/02/01 19:35 27m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci error
2026/02/01 19:35 26m retest repro upstream OK log
2025/11/09 02:01 51m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci report log
2025/10/10 11:26 1h40m retest repro linux-next OK log

Sample crash report:
watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [syz.0.76:6894]
Modules linked in:
irq event stamp: 5181
hardirqs last  enabled at (5180): [<ffff80008b064a14>] irqentry_exit+0xd8/0x108 kernel/entry/common.c:214
hardirqs last disabled at (5181): [<ffff80008b062af0>] __enter_from_kernel_mode arch/arm64/kernel/entry-common.c:43 [inline]
hardirqs last disabled at (5181): [<ffff80008b062af0>] enter_from_kernel_mode+0x14/0x34 arch/arm64/kernel/entry-common.c:50
softirqs last  enabled at (522): [<ffff8000892e0188>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last  enabled at (522): [<ffff8000892e0188>] release_sock+0x14c/0x1ac net/core/sock.c:3735
softirqs last disabled at (528): [<ffff8000892f4c84>] spin_lock_bh include/linux/spinlock.h:356 [inline]
softirqs last disabled at (528): [<ffff8000892f4c84>] lock_sock_nested+0x70/0x118 net/core/sock.c:3714
CPU: 0 UID: 0 PID: 6894 Comm: syz.0.76 Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 03400005 (nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : queued_spin_lock_slowpath+0x138/0xaec kernel/locking/qspinlock.c:197
lr : queued_spin_lock_slowpath+0x144/0xaec kernel/locking/qspinlock.c:197
sp : ffff8000a1a17600
x29: ffff8000a1a176a0 x28: 1fffe0001b9124c1 x27: 1fffe000196c6002
x26: ffff0000cb630000 x25: dfff800000000000 x24: ffff700014342ec4
x23: 0000000000000001 x22: ffff0000cb630010 x21: ffff0000dc892608
x20: ffff0000dc892610 x19: ffff0000dc892600 x18: 0000000000000000
x17: 0000000000000000 x16: ffff800080537d14 x15: 0000000000000001
x14: 1fffe0001b9124c0 x13: 0000000000000000 x12: 0000000000000000
x11: ffff60001b9124c1 x10: dfff800000000000 x9 : 0000000000000000
x8 : 0000000000000001 x7 : ffff8000892f4c84 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff80008b0885f8
x2 : 0000000000000000 x1 : 0000000000000001 x0 : 0000000000000001
Call trace:
 __cmpwait_case_8 arch/arm64/include/asm/cmpxchg.h:229 [inline] (P)
 __cmpwait arch/arm64/include/asm/cmpxchg.h:257 [inline] (P)
 queued_spin_lock_slowpath+0x138/0xaec kernel/locking/qspinlock.c:197 (P)
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x2a8/0x2cc kernel/locking/spinlock_debug.c:116
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:127 [inline]
 _raw_spin_lock_bh+0x50/0x60 kernel/locking/spinlock.c:178
 spin_lock_bh include/linux/spinlock.h:356 [inline]
 lock_sock_nested+0x70/0x118 net/core/sock.c:3714
 lock_sock include/net/sock.h:1669 [inline]
 tipc_sendstream+0x50/0x84 net/tipc/socket.c:1545
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg net/socket.c:729 [inline]
 ____sys_sendmsg+0x490/0x7b8 net/socket.c:2614
 ___sys_sendmsg+0x204/0x278 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __arm64_sys_sendmsg+0x184/0x238 net/socket.c:2703
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x254 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:763
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6895 Comm: syz.0.76 Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : should_resched arch/arm64/include/asm/preempt.h:78 [inline]
pc : __local_bh_enable_ip+0x1f0/0x35c kernel/softirq.c:414
lr : __local_bh_enable_ip+0x1ec/0x35c kernel/softirq.c:412
sp : ffff8000a1806210
x29: ffff8000a1806220 x28: 0000000040613361 x27: ffff8000a18063e0
x26: ffff0000f25e3b60 x25: dfff800000000000 x24: 0000000000000001
x23: dfff800000000000 x22: 1fffe000196c63d1 x21: ffff80008ab3e7b8
x20: 0000000000000201 x19: ffff0000cb631e88 x18: 00000000ffffffff
x17: ffff800093605000 x16: ffff80008052bc24 x15: 0000000000000001
x14: 1fffe0001b9124c0 x13: 0000000000000000 x12: 0000000000000000
x11: ffff800093404c28 x10: 0000000000000003 x9 : 0000000000000000
x8 : 000000000382547a x7 : ffff80008ab4aee0 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000010
x2 : 0000000000000002 x1 : ffff80008ee54d8e x0 : ffff80010c40c000
Call trace:
 __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:26 [inline] (P)
 arch_local_irq_enable arch/arm64/include/asm/irqflags.h:48 [inline] (P)
 __local_bh_enable_ip+0x1f0/0x35c kernel/softirq.c:412 (P)
 __raw_spin_trylock_bh include/linux/spinlock_api_smp.h:177 [inline]
 _raw_spin_trylock_bh+0x68/0x80 kernel/locking/spinlock.c:146
 spin_trylock_bh include/linux/spinlock.h:411 [inline]
 tipc_sk_rcv+0x2f4/0x2294 net/tipc/socket.c:2494
 tipc_node_xmit+0x18c/0xc9c net/tipc/node.c:1701
 tipc_node_xmit_skb net/tipc/node.c:1766 [inline]
 tipc_node_distr_xmit+0x248/0x33c net/tipc/node.c:1781
 tipc_sk_rcv+0x1df0/0x2294 net/tipc/socket.c:2499
 tipc_node_xmit+0x18c/0xc9c net/tipc/node.c:1701
 tipc_sk_push_backlog+0x398/0x744 net/tipc/socket.c:1312
 tipc_sk_conn_proto_rcv net/tipc/socket.c:1366 [inline]
 tipc_sk_proto_rcv+0x704/0x12ec net/tipc/socket.c:2156
 tipc_sk_filter_rcv+0x2524/0x277c net/tipc/socket.c:2350
 tipc_sk_enqueue net/tipc/socket.c:2443 [inline]
 tipc_sk_rcv+0x628/0x2294 net/tipc/socket.c:2495
 tipc_node_xmit+0x18c/0xc9c net/tipc/node.c:1701
 tipc_node_xmit_skb net/tipc/node.c:1766 [inline]
 tipc_node_distr_xmit+0x248/0x33c net/tipc/node.c:1781
 tipc_sk_backlog_rcv+0x164/0x214 net/tipc/socket.c:2410
 sk_backlog_rcv include/net/sock.h:1150 [inline]
 __release_sock+0x19c/0x39c net/core/sock.c:3172
 release_sock+0x60/0x1ac net/core/sock.c:3726
 sockopt_release_sock net/core/sock.c:1155 [inline]
 sk_setsockopt+0x2354/0x28ec net/core/sock.c:1668
 sock_setsockopt+0x68/0x80 net/core/sock.c:1675
 do_sock_setsockopt+0x19c/0x328 net/socket.c:2340
 __sys_setsockopt net/socket.c:2369 [inline]
 __do_sys_setsockopt net/socket.c:2375 [inline]
 __se_sys_setsockopt net/socket.c:2372 [inline]
 __arm64_sys_setsockopt+0x170/0x1e0 net/socket.c:2372
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x254 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:763
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Crashes (44):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/18 05:53 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci bf45a62baffc 1c8c8cd8 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: soft lockup in sys_sendmsg
2025/12/30 05:44 bpf 22cc16c04b78 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce BUG: soft lockup in sys_sendmsg
2025/05/16 16:19 bpf b4432656b36e cfde8269 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce BUG: soft lockup in sys_sendmsg
2026/03/26 09:28 bpf-next 400ff899c336 c6143aac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: soft lockup in sys_sendmsg
2026/03/14 17:55 bpf-next bb41fcef5c79 ee8d34d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: soft lockup in sys_sendmsg
2026/03/01 22:10 bpf-next 309d8808eef9 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: soft lockup in sys_sendmsg
2026/02/21 09:42 bpf-next 9cd168a2720b 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: soft lockup in sys_sendmsg
2026/02/08 08:39 bpf-next db975debcb8c 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: soft lockup in sys_sendmsg
2026/02/07 06:56 bpf-next b8c89f5cc203 f20fc9f9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: soft lockup in sys_sendmsg
2025/05/29 18:04 bpf-next 90b83efa6701 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: soft lockup in sys_sendmsg
2025/04/26 13:37 bpf-next 91dbac407653 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce BUG: soft lockup in sys_sendmsg
2025/10/14 18:50 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci bf45a62baffc b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: soft lockup in sys_sendmsg
2025/08/15 01:19 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f5ae30d69d7 dcc075fb .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: soft lockup in sys_sendmsg
2026/03/16 13:48 upstream f338e7738378 64e21424 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in sys_sendmsg
2026/01/10 23:50 upstream b6151c4e60e5 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in sys_sendmsg
2026/01/05 23:19 upstream 3609fa95fb0f d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in sys_sendmsg
2025/12/26 02:08 upstream ccd1cdca5cd4 d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in sys_sendmsg
2025/12/02 06:41 upstream 1d18101a644e d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in sys_sendmsg
2025/09/14 20:44 upstream f83a4f2a4d8c e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in sys_sendmsg
2025/07/03 22:01 upstream 17bbde2e1716 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in sys_sendmsg
2025/06/05 07:06 upstream 64980441d269 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in sys_sendmsg
2025/06/05 02:14 upstream 1af80d00e1e0 fd5e6e61 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in sys_sendmsg
2025/05/08 17:39 upstream 2c89c1b655c0 dbf35fa1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in sys_sendmsg
2025/08/17 13:43 upstream 99bade344cfa 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in sys_sendmsg
2026/03/18 14:40 net 64dcbde7f8f8 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2026/03/11 23:29 net 908c344d5cfa 2d88ab01 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2026/03/06 22:40 net f76a93241d71 41d8037d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2026/03/04 10:21 net 46d0d6f50dab 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2026/02/12 10:22 net bf9cf80cab81 76a109e2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2026/02/11 07:51 net 3a23b80dd72d 441e25b7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2026/02/10 14:39 net ae88a5d2f29b 91d776d3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2026/02/03 16:35 net 3125fc170169 6df4c87a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2025/12/03 14:12 net 108f9405ce81 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2025/11/17 01:41 net 5442a9da6978 f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2025/10/26 01:53 net 84a905290cb4 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2025/09/24 12:49 net ca9f9cdc4de9 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2025/09/09 11:02 net 1dbfb0363224 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2025/06/30 14:03 net 2def09ead4ad fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_sendmsg
2026/01/18 06:28 net-next b79040468016 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in sys_sendmsg
2025/09/04 12:49 net-next 0e2a5208cc3d d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in sys_sendmsg
2025/08/18 11:23 net-next bab3ce404553 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in sys_sendmsg
2025/11/21 06:21 linux-next 88cbd8ac379c 280ea308 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in sys_sendmsg
2025/09/18 08:45 linux-next ae2d20002576 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in sys_sendmsg
2025/09/02 04:28 linux-next 7fa4d8dc380f 807a3b61 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: rcu detected stall in sys_sendmsg
* Struck through repros no longer work on HEAD.