ci2 starts bisection 2025-08-11 14:20:59.719979001 +0000 UTC m=+259946.560278391
bisecting fixing commit since dfc486ec9cce9eaaeb72cca8fcf04cd1ed230905
building syzkaller on 3cda49cfaa8556b73277ccd7e75952f0f2de2d74
ensuring issue is reproducible on original commit dfc486ec9cce9eaaeb72cca8fcf04cd1ed230905
testing commit dfc486ec9cce9eaaeb72cca8fcf04cd1ed230905 gcc
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
kernel signature: 835d748c23509bbba5882db5b19576da21be774cc21b4d7151993fce08841f2b
all runs: crashed: INFO: task hung in blkdev_put
representative crash: INFO: task hung in blkdev_put, types: [HANG]
check whether we can drop unnecessary instrumentation
disabling configs for [ubsan bug_or_warning kasan locking atomic_sleep memleak], they are not needed
testing commit dfc486ec9cce9eaaeb72cca8fcf04cd1ed230905 gcc
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
kernel signature: 4e961bbb519712db4b94616520c14a06d35bd1ce36a30d538d60d649d8550fb7
all runs: crashed: INFO: task hung in blkdev_put
representative crash: INFO: task hung in blkdev_put, types: [HANG]
the bug reproduces without the instrumentation
disabling configs for [memleak ubsan bug_or_warning kasan locking atomic_sleep], they are not needed
kconfig minimization: base=3829 full=7620 leaves diff=2130
split chunks (needed=false): <2130>
split chunk #0 of len 2130 into 5 parts
testing without sub-chunk 1/5
disabling configs for [memleak ubsan bug_or_warning kasan locking atomic_sleep], they are not needed
testing commit dfc486ec9cce9eaaeb72cca8fcf04cd1ed230905 gcc
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
kernel signature: 2fbdca58a6aa96e6fa1b6d82b07c9bc081f3b4f27c9f2448c17fcbc0680d828b
all runs: OK
false negative chance: 0.000
testing without sub-chunk 2/5
disabling configs for [bug_or_warning kasan locking atomic_sleep memleak ubsan], they are not needed
testing commit dfc486ec9cce9eaaeb72cca8fcf04cd1ed230905 gcc
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
kernel signature: 544f004feeb4438c253ab3d72ff41c8069305a69420e3c37707ed61f885e39df
all runs: crashed: INFO: task hung in blkdev_put
representative crash: INFO: task hung in blkdev_put, types: [HANG]
the chunk can be dropped
testing without sub-chunk 3/5
disabling configs for [bug_or_warning kasan locking atomic_sleep memleak ubsan], they are not needed
testing commit dfc486ec9cce9eaaeb72cca8fcf04cd1ed230905 gcc
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
kernel signature: 8454e7429920dc035f413fffb1b73e200dafaa0143677655246755031692f797
all runs: crashed: INFO: task hung in blkdev_put
representative crash: INFO: task hung in blkdev_put, types: [HANG]
the chunk can be dropped
testing without sub-chunk 4/5
disabling configs for [ubsan bug_or_warning kasan locking atomic_sleep memleak], they are not needed
testing commit dfc486ec9cce9eaaeb72cca8fcf04cd1ed230905 gcc
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
kernel signature: 41c2bc4dd710a672c646c83bd468643f0880f06e8fded4f08d97dad49644a422
all runs: crashed: INFO: task hung in blkdev_put
representative crash: INFO: task hung in blkdev_put, types: [HANG]
the chunk can be dropped
testing without sub-chunk 5/5
disabling configs for [bug_or_warning kasan locking atomic_sleep memleak ubsan], they are not needed
testing commit dfc486ec9cce9eaaeb72cca8fcf04cd1ed230905 gcc
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
kernel signature: 94e7fe760dcc563d7ae284f3ad766be2e919574dbf209c4b9ed3ffed710aebf5
all runs: crashed: INFO: task hung in blkdev_put
representative crash: INFO: task hung in blkdev_put, types: [HANG]
the chunk can be dropped
minimized to 426 configs; suspects: [6LOWPAN 6LOWPAN_GHC_EXT_HDR_DEST 6LOWPAN_GHC_EXT_HDR_FRAG 6LOWPAN_GHC_EXT_HDR_HOP 6LOWPAN_GHC_EXT_HDR_ROUTE 6LOWPAN_GHC_ICMPV6 6LOWPAN_GHC_UDP 6LOWPAN_NHC 6LOWPAN_NHC_DEST 6LOWPAN_NHC_FRAGMENT 6LOWPAN_NHC_HOP 6LOWPAN_NHC_IPV6 6LOWPAN_NHC_MOBILITY 6LOWPAN_NHC_ROUTING 6LOWPAN_NHC_UDP 6PACK 842_COMPRESS 842_DECOMPRESS 9P_FSCACHE 9P_FS_POSIX_ACL 9P_FS_SECURITY ACORN_PARTITION ACORN_PARTITION_ADFS ACORN_PARTITION_CUMANA ACORN_PARTITION_EESOX ACORN_PARTITION_ICS ACORN_PARTITION_POWERTEC ACORN_PARTITION_RISCIX ACPI_NFIT ACPI_PLATFORM_PROFILE ADFS_FS AFFS_FS AFS_FS AFS_FSCACHE AF_KCM AF_RXRPC AF_RXRPC_IPV6 AIX_PARTITION AMD_SFH_HID AMIGA_PARTITION ANDROID_BINDERFS ANDROID_BINDER_IPC ANON_VMA_NAME APERTURE_HELPERS APPLE_MFI_FASTCHARGE AR5523 ARCH_ENABLE_THP_MIGRATION ASM_MODVERSIONS ASUS_TF103C_DOCK ASYNC_CORE ASYNC_MEMCPY ASYNC_PQ ASYNC_RAID6_RECOV ASYNC_TX_DMA ASYNC_XOR ATARI_PARTITION ATA_GENERIC ATA_OVER_ETH ATH10K ATH10K_CE ATH10K_PCI ATH10K_USB ATH11K ATH6KL ATH6KL_USB ATH9K ATH9K_AHB ATH9K_BTCOEX_SUPPORT ATH9K_CHANNEL_CONTEXT ATH9K_COMMON ATH9K_COMMON_DEBUG ATH9K_COMMON_SPECTRAL ATH9K_DEBUGFS ATH9K_DYNACK ATH9K_HTC ATH9K_HTC_DEBUGFS ATH9K_HW ATH9K_PCI ATH9K_PCOEM ATH9K_RFKILL ATH_COMMON ATM ATM_BR2684 ATM_CLIP ATM_DRIVERS ATM_LANE ATM_MPOA ATM_TCP AUXILIARY_BUS AX25 AX25_DAMA_SLAVE AX88796B_PHY BAREUDP BATMAN_ADV BATMAN_ADV_BATMAN_V BATMAN_ADV_BLA BATMAN_ADV_DAT BATMAN_ADV_MCAST BATMAN_ADV_NC BCACHE BCMA BCMA_HOST_PCI_POSSIBLE BEFS_FS BFQ_CGROUP_DEBUG BFQ_GROUP_IOSCHED BFS_FS BIG_KEYS BLK_CGROUP_RWSTAT BLK_DEBUG_FS_ZONED BLK_DEV_BSGLIB BLK_DEV_INTEGRITY BLK_DEV_INTEGRITY_T10 BLK_DEV_NBD BLK_DEV_NULL_BLK BLK_DEV_NULL_BLK_FAULT_INJECTION BLK_DEV_NVME BLK_DEV_PMEM BLK_DEV_RAM BLK_DEV_RNBD BLK_DEV_RNBD_CLIENT BLK_DEV_THROTTLING BLK_ICQ BLK_INLINE_ENCRYPTION BLK_INLINE_ENCRYPTION_FALLBACK BLK_MQ_RDMA BLK_WBT BLK_WBT_MQ BONDING BOOT_VESA_SUPPORT BPF_EVENTS BPF_JIT BPF_JIT_ALWAYS_ON BPF_JIT_DEFAULT_ON BPF_LSM BPF_PRELOAD BPF_PRELOAD_UMD BPF_STREAM_PARSER BPF_SYSCALL BPQETHER BRIDGE BRIDGE_CFM BRIDGE_EBT_802_3 BRIDGE_EBT_AMONG BRIDGE_EBT_ARP BRIDGE_EBT_ARPREPLY BRIDGE_EBT_BROUTE BRIDGE_EBT_DNAT BRIDGE_EBT_IP BRIDGE_EBT_IP6 BRIDGE_EBT_LIMIT BRIDGE_EBT_LOG BRIDGE_EBT_MARK BRIDGE_EBT_MARK_T BRIDGE_EBT_NFLOG BRIDGE_EBT_PKTTYPE BRIDGE_EBT_REDIRECT BRIDGE_EBT_SNAT BRIDGE_EBT_STP BRIDGE_EBT_T_FILTER BRIDGE_EBT_T_NAT BRIDGE_EBT_VLAN BRIDGE_IGMP_SNOOPING BRIDGE_MRP BRIDGE_NF_EBTABLES BRIDGE_VLAN_FILTERING BSD_DISKLABEL BSD_PROCESS_ACCT_V3 BT BTRFS_ASSERT BTRFS_FS BTRFS_FS_POSIX_ACL BTRFS_FS_REF_VERIFY BTT BT_6LOWPAN BT_ATH3K BT_BCM BT_BNEP BT_BNEP_MC_FILTER BT_BNEP_PROTO_FILTER BT_BREDR BT_CMTP BT_HCIBCM203X BT_HCIBFUSB BT_HCIBPA10X BT_HCIBTUSB BT_HCIBTUSB_AUTOSUSPEND BT_HCIBTUSB_BCM BT_HCIBTUSB_MTK BT_HCIBTUSB_RTL BT_HCIUART BT_HCIUART_3WIRE BT_HCIUART_AG6XX BT_HCIUART_BCSP BT_HCIUART_H4 BT_HCIUART_LL BT_HCIUART_MRVL BT_HCIUART_QCA BT_HCIUART_SERDEV BT_HCIVHCI BT_HIDP BT_HS BT_INTEL BT_LE BT_LEDS BT_MSFTEXT BT_MTK BT_QCA BT_RFCOMM BT_RFCOMM_TTY BT_RTL CACHEFILES CAIF CAIF_DEBUG CAIF_DRIVERS CAIF_NETDEV CAIF_TTY CAIF_USB CAIF_VIRTIO CAN CAN_8DEV_USB CAN_BCM CAN_CALC_BITTIMING CAN_DEV CAN_EMS_USB CAN_ESD_USB CAN_ETAS_ES58X CAN_GS_USB CAN_GW CAN_IFI_CANFD CAN_ISOTP CAN_J1939 CAN_KVASER_USB CAN_MCBA_USB CAN_NETLINK CAN_PEAK_USB CAN_RAW CAN_SLCAN CAN_UCAN CAN_VCAN CAN_VXCAN CAPI_TRACE CARL9170 CARL9170_HWRNG CARL9170_LEDS CARL9170_WPC CEC_CORE CEPH_FS CEPH_FSCACHE CEPH_FS_POSIX_ACL CEPH_LIB CEPH_LIB_USE_DNS_RESOLVER CFG80211 CFG80211_CRDA_SUPPORT CFG80211_DEBUGFS CFG80211_DEFAULT_PS CFG80211_REQUIRE_SIGNED_REGDB CFG80211_USE_KERNEL_REGDB_KEYS CFG80211_WEXT CFS_BANDWIDTH CGROUP_BPF CHARGER_ISP1704 CHR_DEV_ST CIFS CIFS_ALLOW_INSECURE_LEGACY CIFS_DEBUG CIFS_DFS_UPCALL CIFS_FSCACHE CIFS_POSIX CIFS_SMB_DIRECT CIFS_SWN_UPCALL CIFS_UPCALL CIFS_XATTR CLS_U32_MARK CLS_U32_PERF CMA CMA_SIZE_SEL_MBYTES CMDLINE_PARTITION COMEDI COMEDI_8254 COMEDI_8255 COMEDI_8255_PCI COMEDI_8255_SA COMEDI_ADL_PCI9118 COMEDI_ADQ12B COMEDI_AIO_AIO12_8 COMEDI_AIO_IIRO_16 COMEDI_AMPLC_DIO200 COMEDI_AMPLC_DIO200_ISA COMEDI_AMPLC_PC236 COMEDI_AMPLC_PC236_ISA COMEDI_AMPLC_PC263_ISA COMEDI_BOND COMEDI_C6XDIGIO COMEDI_DAC02 COMEDI_DAS08 COMEDI_DAS08_ISA COMEDI_DAS16M1 COMEDI_DAS1800 COMEDI_DAS6402 COMEDI_DAS800 COMEDI_DMM32AT COMEDI_DT2801 COMEDI_DT2811 COMEDI_DT2814 COMEDI_DT2815 COMEDI_DT2817 COMEDI_DT282X COMEDI_DT9812 COMEDI_FL512 COMEDI_ISADMA COMEDI_ISA_DRIVERS COMEDI_KCOMEDILIB COMEDI_MISC_DRIVERS COMEDI_MPC624 COMEDI_MULTIQ3 COMEDI_NI_ATMIO16D COMEDI_NI_AT_A2150 COMEDI_NI_AT_AO COMEDI_NI_DAQ_700_CS COMEDI_NI_LABPC COMEDI_NI_LABPC_CS COMEDI_NI_LABPC_ISA COMEDI_NI_LABPC_ISADMA COMEDI_NI_LABPC_PCI COMEDI_NI_USB6501 COMEDI_PARPORT COMEDI_PCI_DRIVERS COMEDI_PCL711 COMEDI_PCL724 COMEDI_PCL726 COMEDI_PCL730 COMEDI_PCL812 COMEDI_PCL816 COMEDI_PCL818 COMEDI_PCM3724 COMEDI_PCMAD COMEDI_PCMCIA_DRIVERS COMEDI_PCMDA12 COMEDI_PCMMIO COMEDI_PCMUIO COMEDI_RTI800 COMEDI_RTI802 COMEDI_S526 COMEDI_TEST COMEDI_USBDUX COMEDI_USBDUXFAST COMEDI_USBDUXSIGMA COMEDI_USB_DRIVERS COMEDI_VMK80XX COMPAT_NETLINK_MESSAGES COUNTER CRAMFS CRAMFS_BLOCKDEV CRAMFS_MTD CRC4 CRC64 CRC64_ROCKSOFT CRC7 CRC8 CRC_ITU_T CRC_T10DIF CRYPTO_ADIANTUM CRYPTO_AEGIS128 CRYPTO_AEGIS128_AESNI_SSE2 CRYPTO_AES_NI_INTEL CRYPTO_AES_TI CRYPTO_ANSI_CPRNG CRYPTO_ANUBIS CRYPTO_ARC4 CRYPTO_ARCH_HAVE_LIB_BLAKE2S CRYPTO_ARCH_HAVE_LIB_CHACHA CRYPTO_ARCH_HAVE_LIB_CURVE25519 CRYPTO_ARCH_HAVE_LIB_POLY1305 CRYPTO_ARIA CRYPTO_ARIA_AESNI_AVX_X86_64 CRYPTO_BLAKE2B CRYPTO_BLAKE2S_X86 CRYPTO_BLOWFISH CRYPTO_BLOWFISH_COMMON CRYPTO_BLOWFISH_X86_64 CRYPTO_CAMELLIA CRYPTO_CAMELLIA_AESNI_AVX2_X86_64 CRYPTO_CAMELLIA_AESNI_AVX_X86_64 CRYPTO_CAMELLIA_X86_64 CRYPTO_CAST5 CRYPTO_CAST5_AVX_X86_64 CRYPTO_CAST6 CRYPTO_CAST6_AVX_X86_64 CRYPTO_CAST_COMMON CRYPTO_CHACHA20 CRYPTO_CHACHA20POLY1305 CRYPTO_CHACHA20_X86_64 CRYPTO_CRC32 CRYPTO_CRC32C_INTEL CRYPTO_CRC32_PCLMUL CRYPTO_CRC64_ROCKSOFT CRYPTO_CRCT10DIF CRYPTO_CRCT10DIF_PCLMUL CRYPTO_CRYPTD CRYPTO_CTS CRYPTO_CURVE25519 CRYPTO_CURVE25519_X86 CRYPTO_DEFLATE CRYPTO_DES CRYPTO_DES3_EDE_X86_64 CRYPTO_DEV_CCP CRYPTO_DEV_CCP_DD CRYPTO_DEV_PADLOCK CRYPTO_DEV_PADLOCK_AES CRYPTO_DEV_PADLOCK_SHA CRYPTO_DEV_QAT CRYPTO_DEV_QAT_C3XXX CRYPTO_DEV_QAT_C3XXXVF CRYPTO_DEV_QAT_C62X CRYPTO_DEV_QAT_C62XVF CRYPTO_DEV_QAT_DH895xCC CRYPTO_DEV_QAT_DH895xCCVF CRYPTO_DEV_VIRTIO CRYPTO_DH CRYPTO_DRBG_CTR CRYPTO_DRBG_HASH CRYPTO_ECB CRYPTO_ECC CRYPTO_ECDH CRYPTO_ECRDSA CRYPTO_ENGINE CRYPTO_ESSIV CRYPTO_FCRYPT CRYPTO_GHASH_CLMUL_NI_INTEL CRYPTO_HCTR2 CRYPTO_KDF800108_CTR CRYPTO_KEYWRAP CRYPTO_KHAZAD CRYPTO_KPP CRYPTO_LIB_ARC4 CRYPTO_LIB_CHACHA CRYPTO_LIB_CHACHA20POLY1305 CRYPTO_LIB_CHACHA_GENERIC CRYPTO_LIB_CURVE25519 CRYPTO_LIB_CURVE25519_GENERIC CRYPTO_LIB_DES CRYPTO_LIB_POLY1305 CRYPTO_LIB_POLY1305_GENERIC CRYPTO_LRW CRYPTO_MICHAEL_MIC CRYPTO_NHPOLY1305 CRYPTO_NHPOLY1305_AVX2 CRYPTO_NHPOLY1305_SSE2 CRYPTO_PCBC CRYPTO_PCRYPT CRYPTO_POLY1305 CRYPTO_POLY1305_X86_64 CRYPTO_POLYVAL CRYPTO_POLYVAL_CLMUL_NI CRYPTO_RMD160 CRYPTO_SEED CRYPTO_SERPENT CRYPTO_SERPENT_AVX2_X86_64 CRYPTO_SERPENT_AVX_X86_64 CRYPTO_SERPENT_SSE2_X86_64 CRYPTO_SHA1_SSSE3 CRYPTO_SHA256_SSSE3 CRYPTO_SHA3 CRYPTO_SHA512_SSSE3 CRYPTO_SIMD CRYPTO_SM2 CRYPTO_SM3 CRYPTO_SM3_AVX_X86_64 CRYPTO_SM4 CRYPTO_SM4_AESNI_AVX2_X86_64 CRYPTO_SM4_AESNI_AVX_X86_64 CRYPTO_SM4_GENERIC CRYPTO_STREEBOG CRYPTO_TEA CRYPTO_TWOFISH CRYPTO_TWOFISH_AVX_X86_64 CRYPTO_TWOFISH_COMMON CRYPTO_TWOFISH_X86_64 CRYPTO_TWOFISH_X86_64_3WAY CRYPTO_USER CRYPTO_USER_API CRYPTO_USER_API_AEAD CRYPTO_USER_API_ENABLE_OBSOLETE CRYPTO_USER_API_HASH CRYPTO_USER_API_RNG CRYPTO_USER_API_SKCIPHER CRYPTO_VMAC CRYPTO_WP512 CRYPTO_XCBC CRYPTO_XCTR CRYPTO_XTS CRYPTO_XXHASH CUSE CYPRESS_FIRMWARE DAMON DAMON_DBGFS DAMON_PADDR DAMON_RECLAIM DAMON_VADDR DCA DCB DEFAULT_PFIFO_FAST DMA_CMA FSCACHE FUSE_FS GPIOLIB HAMRADIO INFINIBAND INFINIBAND_ADDR_TRANS INFINIBAND_RTRS_CLIENT IOSCHED_BFQ ISDN ISDN_CAPI LIBNVDIMM MAC80211 MAC80211_LEDS MEDIA_SUPPORT MTD NET_CLS_U32 NET_SCH_DEFAULT PARTITION_ADVANCED PCCARD PCMCIA RFKILL SERIAL_DEV_BUS TLS TLS_DEVICE USB_GADGET USB_PHY VLAN_8021Q WANT_COMPAT_NETLINK_MESSAGES WEXT_CORE WIRELESS WIRELESS_EXT WLAN WLAN_VENDOR_ATH]
disabling configs for [memleak ubsan bug_or_warning kasan locking atomic_sleep], they are not needed
testing current HEAD 3594f306da129190de25938b823f353ef7f9e322
testing commit 3594f306da129190de25938b823f353ef7f9e322 gcc
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
kernel signature: bc5beba663eacbf4bd518a37602ba5a74e37579ab44f3d2d3fe1878c36b5ac02
all runs: crashed: INFO: task hung in blkdev_put
representative crash: INFO: task hung in blkdev_put, types: [HANG]
crash still not fixed/happens on the oldest tested release
revisions tested: 8, total time: 2h30m32.785044289s (build: 1h17m8.202675762s, test: 1h9m21.834587969s)
crash still not fixed or there were kernel test errors
commit msg: Linux 6.1.147
crash: INFO: task hung in blkdev_put
INFO: task syz.2.16:2790 blocked for more than 143 seconds.
Not tainted 6.1.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.16 state:D stack:14256 pid:2790 ppid:2390 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x568/0x840 kernel/sched/core.c:6561
schedule+0x50/0xb0 kernel/sched/core.c:6637
schedule_preempt_disabled+0x2e/0x40 kernel/sched/core.c:6696
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x44c/0x9b0 kernel/locking/mutex.c:747
blkdev_put+0x4d/0x1b0 block/bdev.c:913
blkdev_close+0xf/0x20 block/fops.c:514
__fput+0x7a/0x230 fs/file_table.c:320
task_work_run+0x7a/0xa0 kernel/task_work.c:203
get_signal+0x65/0x750 kernel/signal.c:2648
arch_do_signal_or_restart+0x92/0x670 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x6b/0xd0 kernel/entry/common.c:174
exit_to_user_mode_prepare+0x64/0xb0 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fee07bbe929
RSP: 002b:00007fee06e2e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007fee07de5fa0 RCX: 00007fee07bbe929
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007fee07c40b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fee07de5fa0 R15: 00007ffeac317e48
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8357ad28 (rcu_tasks.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_one_gp kernel/rcu/tasks.h:517 [inline]
#0: ffffffff8357ad28 (rcu_tasks.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_kthread+0x97/0x4c0 kernel/rcu/tasks.h:562
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8357b350 (rcu_tasks_trace.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_one_gp kernel/rcu/tasks.h:517 [inline]
#0: ffffffff8357b350 (rcu_tasks_trace.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_kthread+0x97/0x4c0 kernel/rcu/tasks.h:562
1 lock held by khungtaskd/28:
#0: ffffffff8357aae8 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8357aae8 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8357aae8 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x2a/0xf0 kernel/locking/lockdep.c:6513
2 locks held by getty/945:
#0: ffff8881092b5098 (&tty->ldisc_sem){....}-{0:0}, at: tty_ldisc_ref_wait+0x1c/0x40 drivers/tty/tty_ldisc.c:244
#1: ffffc900020532f0 (&ldata->atomic_read_lock){....}-{3:3}, at: n_tty_read+0x19e/0x6d0 drivers/tty/n_tty.c:2198
1 lock held by udevd/1926:
#0: ffff88810f6564c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0x8c/0x2e0 block/bdev.c:815
1 lock held by udevd/2365:
#0: ffff888100ebb4c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0x8c/0x2e0 block/bdev.c:815
1 lock held by syz.2.16/2790:
#0: ffff88810f6564c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x4d/0x1b0 block/bdev.c:913
1 lock held by udevd/2795:
#0: ffff888100eb8cc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0x8c/0x2e0 block/bdev.c:815
1 lock held by syz.3.43/3246:
#0: ffff888100eb8cc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x4d/0x1b0 block/bdev.c:913
1 lock held by udevd/3251:
#0: ffff8881096784c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0x8c/0x2e0 block/bdev.c:815
1 lock held by syz.4.99/3773:
#0: ffff888100ebb4c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x4d/0x1b0 block/bdev.c:913
1 lock held by udevd/3777:
#0: ffff888100ebdcc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0x8c/0x2e0 block/bdev.c:815
1 lock held by syz.5.104/4185:
#0: ffff888100ebdcc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x4d/0x1b0 block/bdev.c:913
1 lock held by udevd/4190:
#0: ffff888100ef5cc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0x8c/0x2e0 block/bdev.c:815
1 lock held by syz.6.111/4602:
#0: ffff888100ef5cc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x4d/0x1b0 block/bdev.c:913
1 lock held by udevd/4607:
#0: ffff88810967acc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0x8c/0x2e0 block/bdev.c:815
1 lock held by syz.7.120/5025:
#0: ffff8881096784c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x4d/0x1b0 block/bdev.c:913
1 lock held by syz.8.127/5443:
#0: ffff88810967acc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x4d/0x1b0 block/bdev.c:913
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.147-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x74/0xbb lib/dump_stack.c:106
nmi_cpu_backtrace+0x102/0x160 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0xa5/0x160 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0x533/0x560 kernel/hung_task.c:377
kthread+0xcc/0xe0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 11 Comm: kworker/u4:1 Not tainted 6.1.147-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:__default_send_IPI_dest_field+0x38/0x60 arch/x86/kernel/apic/ipi.c:173
Code: a9 00 10 00 00 74 10 f3 90 8b 04 25 00 c3 5f ff a9 00 10 00 00 75 f0 c1 e7 18 89 3c 25 10 c3 5f ff 09 d6 89 34 25 00 c3 5f ff <5b> 5d c3 48 8b 05 36 5a 0e 02 89 d3 89 fd ff 50 28 89 ef 89 da be
RSP: 0018:ffffc90000063c90 EFLAGS: 00000002
RAX: 00000000000008fb RBX: 0000000000000282 RCX: 0000000000000000
RDX: 0000000000000800 RSI: 00000000000008fb RDI: 0000000001000000
RBP: 0000000000000002 R08: 0000000000000003 R09: ffff888237d2e3d0
R10: 0000000000000000 R11: 0000000000052400 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888237c34b00 R15: ffff888237d2e3c0
FS: 0000000000000000(0000) GS:ffff888237d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00635d000 CR3: 0000000003421000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
_flat_send_IPI_mask arch/x86/kernel/apic/apic_flat_64.c:56 [inline]
flat_send_IPI_mask+0x30/0x80 arch/x86/kernel/apic/apic_flat_64.c:64
smp_call_function_many_cond+0x37a/0x580 kernel/smp.c:978
on_each_cpu_cond_mask+0x36/0x60 kernel/smp.c:1166
on_each_cpu include/linux/smp.h:71 [inline]
text_poke_sync arch/x86/kernel/alternative.c:1574 [inline]
text_poke_bp_batch+0x1fb/0x2d0 arch/x86/kernel/alternative.c:1836
text_poke_flush arch/x86/kernel/alternative.c:1965 [inline]
text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972
arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
static_key_disable_cpuslocked kernel/jump_label.c:237 [inline]
static_key_disable+0x3b/0x60 kernel/jump_label.c:245
toggle_allocation_gate+0x1df/0x230 mm/kfence/core.c:819
process_one_work+0x27d/0x4c0 kernel/workqueue.c:2292
worker_thread+0x236/0x3a0 kernel/workqueue.c:2439
kthread+0xcc/0xe0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295