Extracting prog: 6m18.915466122s
Minimizing prog: 1h6m16.171447918s
Simplifying prog options: 0s
Extracting C: 3m14.648446208s
Simplifying C: 22m37.414199163s


extracting reproducer from 1 programs
testing a last program of every proc
single: executing 1 programs separately with timeout 30s
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
r1 = syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000)={<r2=>0xffffffffffffffff})
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={&(0x7f0000000080)={0x68, r1, 0x1, 0xfffffffe, 0x0, {}, [@NBD_ATTR_INDEX={0x8, 0x1, 0x0}, @NBD_ATTR_SERVER_FLAGS={0xc, 0x5, 0xfb2e77a8993c191b}, @NBD_ATTR_SIZE_BYTES={0xc, 0x2, 0xffff}, @NBD_ATTR_SOCKETS={0x28, 0x7, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}]}, @NBD_ATTR_DEAD_CONN_TIMEOUT={0xc, 0x8, 0x7fffffff}]}, 0x68}}, 0x20000000)

program did not crash
single: failed to extract reproducer
single: executing 1 programs separately with timeout 6m0s
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
r1 = syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000)={<r2=>0xffffffffffffffff})
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={&(0x7f0000000080)={0x68, r1, 0x1, 0xfffffffe, 0x0, {}, [@NBD_ATTR_INDEX={0x8, 0x1, 0x0}, @NBD_ATTR_SERVER_FLAGS={0xc, 0x5, 0xfb2e77a8993c191b}, @NBD_ATTR_SIZE_BYTES={0xc, 0x2, 0xffff}, @NBD_ATTR_SOCKETS={0x28, 0x7, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}]}, @NBD_ATTR_DEAD_CONN_TIMEOUT={0xc, 0x8, 0x7fffffff}]}, 0x68}}, 0x20000000)

program crashed: INFO: task hung in nbd_queue_rq
single: successfully extracted reproducer
found reproducer with 4 syscalls
minimizing guilty program
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd
detailed listing:
executing program 0:
syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000))

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
r1 = syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={&(0x7f0000000080)={0x68, r1, 0x1, 0xfffffffe, 0x0, {}, [@NBD_ATTR_INDEX={0x8, 0x1, 0x0}, @NBD_ATTR_SERVER_FLAGS={0xc, 0x5, 0xfb2e77a8993c191b}, @NBD_ATTR_SIZE_BYTES={0xc, 0x2, 0xffff}, @NBD_ATTR_SOCKETS={0x28, 0x7, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, {0x8}}, {0xc, 0x1, 0x0, 0x1, {0x8}}, {0xc, 0x1, 0x0, 0x1, {0x8}}]}, @NBD_ATTR_DEAD_CONN_TIMEOUT={0xc, 0x8, 0x7fffffff}]}, 0x68}}, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000)={<r1=>0xffffffffffffffff})
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={&(0x7f0000000080)={0x68, 0x0, 0x1, 0xfffffffe, 0x0, {}, [@NBD_ATTR_INDEX={0x8, 0x1, 0x0}, @NBD_ATTR_SERVER_FLAGS={0xc, 0x5, 0xfb2e77a8993c191b}, @NBD_ATTR_SIZE_BYTES={0xc, 0x2, 0xffff}, @NBD_ATTR_SOCKETS={0x28, 0x7, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r1}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r1}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r1}}]}, @NBD_ATTR_DEAD_CONN_TIMEOUT={0xc, 0x8, 0x7fffffff}]}, 0x68}}, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000)={<r1=>0xffffffffffffffff})
sendmsg$NBD_CMD_CONNECT(0xffffffffffffffff, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={&(0x7f0000000080)={0x68, r0, 0x1, 0xfffffffe, 0x0, {}, [@NBD_ATTR_INDEX={0x8, 0x1, 0x0}, @NBD_ATTR_SERVER_FLAGS={0xc, 0x5, 0xfb2e77a8993c191b}, @NBD_ATTR_SIZE_BYTES={0xc, 0x2, 0xffff}, @NBD_ATTR_SOCKETS={0x28, 0x7, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r1}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r1}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r1}}]}, @NBD_ATTR_DEAD_CONN_TIMEOUT={0xc, 0x8, 0x7fffffff}]}, 0x68}}, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
r1 = syz_genetlink_get_family_id$nbd(0x0, 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000)={<r2=>0xffffffffffffffff})
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={&(0x7f0000000080)={0x68, r1, 0x1, 0xfffffffe, 0x0, {}, [@NBD_ATTR_INDEX={0x8, 0x1, 0x0}, @NBD_ATTR_SERVER_FLAGS={0xc, 0x5, 0xfb2e77a8993c191b}, @NBD_ATTR_SIZE_BYTES={0xc, 0x2, 0xffff}, @NBD_ATTR_SOCKETS={0x28, 0x7, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}]}, @NBD_ATTR_DEAD_CONN_TIMEOUT={0xc, 0x8, 0x7fffffff}]}, 0x68}}, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
r1 = syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, 0x0)
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={&(0x7f0000000080)={0x68, r1, 0x1, 0xfffffffe, 0x0, {}, [@NBD_ATTR_INDEX={0x8, 0x1, 0x0}, @NBD_ATTR_SERVER_FLAGS={0xc, 0x5, 0xfb2e77a8993c191b}, @NBD_ATTR_SIZE_BYTES={0xc, 0x2, 0xffff}, @NBD_ATTR_SOCKETS={0x28, 0x7, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, {0x8}}, {0xc, 0x1, 0x0, 0x1, {0x8}}, {0xc, 0x1, 0x0, 0x1, {0x8}}]}, @NBD_ATTR_DEAD_CONN_TIMEOUT={0xc, 0x8, 0x7fffffff}]}, 0x68}}, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000))
sendmsg$NBD_CMD_CONNECT(r0, 0x0, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000))
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, 0x0}, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000))
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={0x0}}, 0x20000000)

program crashed: lost connection to test machine
suppressed program crash: lost connection to test machine
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
r1 = syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000))
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={&(0x7f0000000080)={0x14, r1, 0x1, 0xfffffffe}, 0x14}}, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
r1 = syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000))
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={&(0x7f0000000080)={0x44, r1, 0x1, 0xfffffffe, 0x0, {}, [@NBD_ATTR_INDEX={0x8, 0x1, 0x0}, @NBD_ATTR_SERVER_FLAGS={0xc, 0x5, 0xfb2e77a8993c191b}, @NBD_ATTR_SIZE_BYTES={0xc, 0x2, 0xffff}, @NBD_ATTR_SOCKETS={0x4}, @NBD_ATTR_DEAD_CONN_TIMEOUT={0xc, 0x8, 0x7fffffff}]}, 0x44}}, 0x20000000)

program did not crash
extracting C reproducer
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
program crashed: INFO: task hung in nbd_queue_rq
simplifying C reproducer
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
program crashed: INFO: task hung in nbd_queue_rq
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
program crashed: INFO: task hung in nbd_queue_rq
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
program crashed: INFO: task hung in nbd_queue_rq
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
program crashed: INFO: task hung in nbd_queue_rq
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
program crashed: INFO: task hung in nbd_queue_rq
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
program crashed: INFO: task hung in nbd_queue_rq
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
program crashed: INFO: task hung in nbd_queue_rq
testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
r1 = syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000)={<r2=>0xffffffffffffffff})
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={&(0x7f0000000080)={0x68, r1, 0x1, 0xfffffffe, 0x0, {}, [@NBD_ATTR_INDEX={0x8, 0x1, 0x0}, @NBD_ATTR_SERVER_FLAGS={0xc, 0x5, 0xfb2e77a8993c191b}, @NBD_ATTR_SIZE_BYTES={0xc, 0x2, 0xffff}, @NBD_ATTR_SOCKETS={0x28, 0x7, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}]}, @NBD_ATTR_DEAD_CONN_TIMEOUT={0xc, 0x8, 0x7fffffff}]}, 0x68}}, 0x20000000)

program crashed: INFO: task hung in nbd_queue_rq
validation run: crashed=true
testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
r1 = syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000)={<r2=>0xffffffffffffffff})
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={&(0x7f0000000080)={0x68, r1, 0x1, 0xfffffffe, 0x0, {}, [@NBD_ATTR_INDEX={0x8, 0x1, 0x0}, @NBD_ATTR_SERVER_FLAGS={0xc, 0x5, 0xfb2e77a8993c191b}, @NBD_ATTR_SIZE_BYTES={0xc, 0x2, 0xffff}, @NBD_ATTR_SOCKETS={0x28, 0x7, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}]}, @NBD_ATTR_DEAD_CONN_TIMEOUT={0xc, 0x8, 0x7fffffff}]}, 0x68}}, 0x20000000)

program crashed: INFO: task hung in nbd_queue_rq
validation run: crashed=true
testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_init_net_socket$nl_generic-syz_genetlink_get_family_id$nbd-socketpair$nbd-sendmsg$NBD_CMD_CONNECT
detailed listing:
executing program 0:
r0 = syz_init_net_socket$nl_generic(0x10, 0x3, 0x10)
r1 = syz_genetlink_get_family_id$nbd(&(0x7f0000000040), 0xffffffffffffffff)
socketpair$nbd(0x1, 0x1, 0x0, &(0x7f0000000000)={<r2=>0xffffffffffffffff})
sendmsg$NBD_CMD_CONNECT(r0, &(0x7f0000001ac0)={0x0, 0x0, &(0x7f0000001a80)={&(0x7f0000000080)={0x68, r1, 0x1, 0xfffffffe, 0x0, {}, [@NBD_ATTR_INDEX={0x8, 0x1, 0x0}, @NBD_ATTR_SERVER_FLAGS={0xc, 0x5, 0xfb2e77a8993c191b}, @NBD_ATTR_SIZE_BYTES={0xc, 0x2, 0xffff}, @NBD_ATTR_SOCKETS={0x28, 0x7, 0x0, 0x1, [{0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}, {0xc, 0x1, 0x0, 0x1, {0x8, 0x1, r2}}]}, @NBD_ATTR_DEAD_CONN_TIMEOUT={0xc, 0x8, 0x7fffffff}]}, 0x68}}, 0x20000000)

program crashed: INFO: task hung in nbd_queue_rq
validation run: crashed=true
reproducing took 1h49m44.595743047s
repro crashed as (corrupted=false):
INFO: task kworker/1:1H:72 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:1H    state:D stack:25728 pid:72    tgid:72    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: kblockd blk_mq_requeue_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x1709/0x5530 kernel/sched/core.c:7231
 __schedule_loop kernel/sched/core.c:7308 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7323
 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
 wait_for_reconnect drivers/block/nbd.c:1107 [inline]
 nbd_handle_cmd drivers/block/nbd.c:1149 [inline]
 nbd_queue_rq+0x889/0x1150 drivers/block/nbd.c:1207
 blk_mq_dispatch_rq_list+0x4af/0x1a00 block/blk-mq.c:2117
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline]
 blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline]
 __blk_mq_sched_dispatch_requests+0xd45/0x1590 block/blk-mq-sched.c:307
 blk_mq_sched_dispatch_requests+0xda/0x1a0 block/blk-mq-sched.c:329
 blk_mq_run_hw_queue+0x368/0x520 block/blk-mq.c:2356
 blk_mq_run_hw_queues+0x271/0x400 block/blk-mq.c:2404
 blk_mq_requeue_work+0x70c/0x770 block/blk-mq.c:1571
 process_one_work+0xaaf/0x1480 kernel/workqueue.c:3379
 process_scheduled_works kernel/workqueue.c:3462 [inline]
 worker_thread+0xb05/0x10d0 kernel/workqueue.c:3543
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Showing all locks held in the system:
locks held by khungtaskd/39: 1, last CPU#0:
 #0: ffffffff8e1c3ac0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8e1c3ac0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffffffff8e1c3ac0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6835
locks held by kworker/1:1H/72: 4, on CPU#1:
 #0: ffff888020ab4938 ((wq_completion)kblockd){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffff888020ab4938 ((wq_completion)kblockd){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffff888020ab4938 ((wq_completion)kblockd){+.+.}-{0:0}, at: process_one_work+0x7fd/0x1480 kernel/workqueue.c:3344
 #1: ffffc9000156fc60 ((work_completion)(&(&q->requeue_work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #1: ffffc9000156fc60 ((work_completion)(&(&q->requeue_work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #1: ffffc9000156fc60 ((work_completion)(&(&q->requeue_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7fd/0x1480 kernel/workqueue.c:3344
 #2: ffff888027243d18 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline]
 #2: ffff888027243d18 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline]
 #2: ffff888027243d18 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x33e/0x520 block/blk-mq.c:2355
 #3: ffff888055e551f0 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xc1/0x1150 drivers/block/nbd.c:1199
locks held by getty/5344: 2, on CPU#0:
 #0: ffff888036d1c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900044c32e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
locks held by udevd/5643: 1, on CPU#1:
 #0: ffff888027dd44c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd00 block/bdev.c:991
locks held by kworker/0:5/5945: 3, on CPU#0:
 #0: ffff88813fe1f938 ((wq_completion)events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffff88813fe1f938 ((wq_completion)events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffff88813fe1f938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7fd/0x1480 kernel/workqueue.c:3344
 #1: ffffc900044dfc60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #1: ffffc900044dfc60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #1: ffffc900044dfc60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7fd/0x1480 kernel/workqueue.c:3344
 #2: ffff88801fed5280 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x135/0x170 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
 watchdog+0xfd7/0x1030 kernel/hung_task.c:561
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 11698 Comm: syz.0.4881 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:-1 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x1d/0x80 kernel/kcov.c:213
Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0d a8 ab d8 10 65 8b 35 c9 ab d8 10 81 e6 00 00 ff 00 <ba> 00 01 00 00 23 91 fc 0b 00 00 89 d7 09 f7 74 11 85 f6 75 39 85
RSP: 0018:ffffc900085a75d8 EFLAGS: 00000246
RAX: ffffffff8218170a RBX: ffff88803b438d38 RCX: ffff8880310e1f40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900085a78d0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1006ca1332 R12: 0000000000000000
R13: 00000000000001a7 R14: fffffffffffffe52 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888125d3c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa106223780 CR3: 000000000dfb0000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 do_zap_pte_range mm/memory.c:1839 [inline]
 zap_pte_range mm/memory.c:1954 [inline]
 zap_pmd_range mm/memory.c:2040 [inline]
 zap_pud_range mm/memory.c:2068 [inline]
 zap_p4d_range mm/memory.c:2089 [inline]
 __zap_vma_range+0xc9a/0x49e0 mm/memory.c:2129
 unmap_vmas+0x390/0x550 mm/memory.c:2198
 exit_mmap+0x293/0x9f0 mm/mmap.c:1300
 __mmput+0xcb/0x3e0 kernel/fork.c:1186
 exit_mm+0x186/0x240 kernel/exit.c:615
 do_exit+0x6cd/0x2360 kernel/exit.c:997
 do_group_exit+0x22d/0x2f0 kernel/exit.c:1152
 __do_sys_exit_group kernel/exit.c:1163 [inline]
 __se_sys_exit_group kernel/exit.c:1161 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1161
 x64_sys_call+0x18bf/0x18c0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x17b/0x530 arch/x86/entry/syscall_64.c:85
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa10634de59
Code: Unable to access opcode bytes at 0x7fa10634de2f.
RSP: 002b:00007ffe09f5ce88 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fa10634de59
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe09f5ceec R08: 0000000000000000 R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000040
R13: 00000000000927c0 R14: 000000000005a37e R15: 00007ffe09f5cf40
 </TASK>

final repro crashed as (corrupted=false):
INFO: task kworker/1:1H:72 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:1H    state:D stack:25728 pid:72    tgid:72    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: kblockd blk_mq_requeue_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x1709/0x5530 kernel/sched/core.c:7231
 __schedule_loop kernel/sched/core.c:7308 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7323
 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
 wait_for_reconnect drivers/block/nbd.c:1107 [inline]
 nbd_handle_cmd drivers/block/nbd.c:1149 [inline]
 nbd_queue_rq+0x889/0x1150 drivers/block/nbd.c:1207
 blk_mq_dispatch_rq_list+0x4af/0x1a00 block/blk-mq.c:2117
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline]
 blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline]
 __blk_mq_sched_dispatch_requests+0xd45/0x1590 block/blk-mq-sched.c:307
 blk_mq_sched_dispatch_requests+0xda/0x1a0 block/blk-mq-sched.c:329
 blk_mq_run_hw_queue+0x368/0x520 block/blk-mq.c:2356
 blk_mq_run_hw_queues+0x271/0x400 block/blk-mq.c:2404
 blk_mq_requeue_work+0x70c/0x770 block/blk-mq.c:1571
 process_one_work+0xaaf/0x1480 kernel/workqueue.c:3379
 process_scheduled_works kernel/workqueue.c:3462 [inline]
 worker_thread+0xb05/0x10d0 kernel/workqueue.c:3543
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Showing all locks held in the system:
locks held by khungtaskd/39: 1, last CPU#0:
 #0: ffffffff8e1c3ac0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8e1c3ac0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffffffff8e1c3ac0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6835
locks held by kworker/1:1H/72: 4, on CPU#1:
 #0: ffff888020ab4938 ((wq_completion)kblockd){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffff888020ab4938 ((wq_completion)kblockd){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffff888020ab4938 ((wq_completion)kblockd){+.+.}-{0:0}, at: process_one_work+0x7fd/0x1480 kernel/workqueue.c:3344
 #1: ffffc9000156fc60 ((work_completion)(&(&q->requeue_work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #1: ffffc9000156fc60 ((work_completion)(&(&q->requeue_work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #1: ffffc9000156fc60 ((work_completion)(&(&q->requeue_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7fd/0x1480 kernel/workqueue.c:3344
 #2: ffff888027243d18 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline]
 #2: ffff888027243d18 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline]
 #2: ffff888027243d18 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x33e/0x520 block/blk-mq.c:2355
 #3: ffff888055e551f0 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xc1/0x1150 drivers/block/nbd.c:1199
locks held by getty/5344: 2, on CPU#0:
 #0: ffff888036d1c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900044c32e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
locks held by udevd/5643: 1, on CPU#1:
 #0: ffff888027dd44c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd00 block/bdev.c:991
locks held by kworker/0:5/5945: 3, on CPU#0:
 #0: ffff88813fe1f938 ((wq_completion)events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffff88813fe1f938 ((wq_completion)events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffff88813fe1f938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7fd/0x1480 kernel/workqueue.c:3344
 #1: ffffc900044dfc60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #1: ffffc900044dfc60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #1: ffffc900044dfc60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7fd/0x1480 kernel/workqueue.c:3344
 #2: ffff88801fed5280 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x135/0x170 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
 watchdog+0xfd7/0x1030 kernel/hung_task.c:561
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 11698 Comm: syz.0.4881 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:-1 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x1d/0x80 kernel/kcov.c:213
Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0d a8 ab d8 10 65 8b 35 c9 ab d8 10 81 e6 00 00 ff 00 <ba> 00 01 00 00 23 91 fc 0b 00 00 89 d7 09 f7 74 11 85 f6 75 39 85
RSP: 0018:ffffc900085a75d8 EFLAGS: 00000246
RAX: ffffffff8218170a RBX: ffff88803b438d38 RCX: ffff8880310e1f40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900085a78d0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1006ca1332 R12: 0000000000000000
R13: 00000000000001a7 R14: fffffffffffffe52 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888125d3c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa106223780 CR3: 000000000dfb0000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 do_zap_pte_range mm/memory.c:1839 [inline]
 zap_pte_range mm/memory.c:1954 [inline]
 zap_pmd_range mm/memory.c:2040 [inline]
 zap_pud_range mm/memory.c:2068 [inline]
 zap_p4d_range mm/memory.c:2089 [inline]
 __zap_vma_range+0xc9a/0x49e0 mm/memory.c:2129
 unmap_vmas+0x390/0x550 mm/memory.c:2198
 exit_mmap+0x293/0x9f0 mm/mmap.c:1300
 __mmput+0xcb/0x3e0 kernel/fork.c:1186
 exit_mm+0x186/0x240 kernel/exit.c:615
 do_exit+0x6cd/0x2360 kernel/exit.c:997
 do_group_exit+0x22d/0x2f0 kernel/exit.c:1152
 __do_sys_exit_group kernel/exit.c:1163 [inline]
 __se_sys_exit_group kernel/exit.c:1161 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1161
 x64_sys_call+0x18bf/0x18c0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x17b/0x530 arch/x86/entry/syscall_64.c:85
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa10634de59
Code: Unable to access opcode bytes at 0x7fa10634de2f.
RSP: 002b:00007ffe09f5ce88 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fa10634de59
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe09f5ceec R08: 0000000000000000 R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000040
R13: 00000000000927c0 R14: 000000000005a37e R15: 00007ffe09f5cf40
 </TASK>