ci2 starts bisection 2025-12-21 12:13:06.502036531 +0000 UTC m=+2155398.679159598
bisecting fixing commit since dbcb8d8e4163e46066f43e2bd9a6779e594ec900
building syzkaller on fb8f743dc82ba3a879228aa71ce09fdc570665d1
ensuring issue is reproducible on original commit dbcb8d8e4163e46066f43e2bd9a6779e594ec900
testing commit dbcb8d8e4163e46066f43e2bd9a6779e594ec900 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: a676a3239aae7f57734e0fc7081fecfc87edae3999b17e9345d3087b94eec1d7
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 [bug_or_warning kasan locking atomic_sleep memleak ubsan], they are not needed
testing commit dbcb8d8e4163e46066f43e2bd9a6779e594ec900 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: 4532be76448cd30270b49c0233524c4b3177347b6f25845c643430a0d26037c7
run #0: crashed: INFO: task hung in blkdev_put
run #1: crashed: INFO: task hung in blkdev_put
run #2: crashed: INFO: task hung in blkdev_put
run #3: crashed: INFO: task hung in blkdev_put
run #4: crashed: INFO: task hung in blkdev_put
run #5: crashed: INFO: task hung in blkdev_put
run #6: crashed: INFO: task hung in blkdev_put
run #7: crashed: INFO: task hung in blkdev_put
run #8: crashed: INFO: task hung in blkdev_put
run #9: OK
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=3913 full=7800 leaves diff=2160
split chunks (needed=false): <2160>
split chunk #0 of len 2160 into 5 parts
testing without sub-chunk 1/5
disabling configs for [kasan locking atomic_sleep memleak ubsan bug_or_warning], they are not needed
testing commit dbcb8d8e4163e46066f43e2bd9a6779e594ec900 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: 4a8216401df89736a2d53d15ab7ade3bca997af293caf27f60b5de51c30cd756
all runs: OK
false negative chance: 0.000
testing without sub-chunk 2/5
disabling configs for [memleak ubsan bug_or_warning kasan locking atomic_sleep], they are not needed
testing commit dbcb8d8e4163e46066f43e2bd9a6779e594ec900 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: 90499c9fd99072e0075b7ad19cd363a31dc3604f8b3b2bd8206858f8b15bd6d7
run #0: crashed: INFO: task hung in blkdev_put
run #1: crashed: INFO: task hung in blkdev_put
run #2: crashed: INFO: task hung in blkdev_put
run #3: crashed: INFO: task hung in blkdev_put
run #4: crashed: INFO: task hung in blkdev_put
run #5: crashed: INFO: task hung in blkdev_put
run #6: crashed: INFO: task hung in blkdev_put
run #7: crashed: INFO: task hung in blkdev_put
run #8: OK
run #9: OK
representative crash: INFO: task hung in blkdev_put, types: [HANG]
the chunk can be dropped
testing without sub-chunk 3/5
disabling configs for [locking atomic_sleep memleak ubsan bug_or_warning kasan], they are not needed
testing commit dbcb8d8e4163e46066f43e2bd9a6779e594ec900 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: 533683394a248961baeb5b513482e0b42a6942b29e1aaed8f095669fdba4f934
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 [memleak ubsan bug_or_warning kasan locking atomic_sleep], they are not needed
testing commit dbcb8d8e4163e46066f43e2bd9a6779e594ec900 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: 1853dfec90b9d178850f385cbcb00efa9d87db4d814dd3ff2cda03dc54b43d0a
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 [kasan locking atomic_sleep memleak ubsan bug_or_warning], they are not needed
testing commit dbcb8d8e4163e46066f43e2bd9a6779e594ec900 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: 16df6c728806bf515e194ac191ef81e61ab3955a0e1042c378ebf7c16dc85bc5
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 432 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_MEMORY_HOTREMOVE ARCH_ENABLE_THP_MIGRATION ARCH_WANT_PMD_MKWRITE 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_PUNT_BIO 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_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_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_POLL_SYNC 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_INTEL BT_LE BT_LEDS BT_LE_L2CAP_ECRED 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_F81604 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_RX_OFFLOAD 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 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_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 DAX DCA DCB DEFAULT_PFIFO_FAST DEVICE_MIGRATION DEVICE_PRIVATE DEV_COREDUMP DEV_DAX DIMLIB 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 MEMORY_HOTPLUG MEMORY_HOTREMOVE MTD NET_CLS_U32 NET_SCH_DEFAULT PARTITION_ADVANCED PCCARD PCMCIA RFKILL SERIAL_DEV_BUS TLS TLS_DEVICE TRANSPARENT_HUGEPAGE USB_GADGET USB_PHY VLAN_8021Q WANT_COMPAT_NETLINK_MESSAGES WEXT_CORE WIRELESS WIRELESS_EXT WLAN WLAN_VENDOR_ATH ZONE_DEVICE]
disabling configs for [memleak ubsan bug_or_warning kasan locking atomic_sleep], they are not needed
testing current HEAD 5fa4793a2d2d70ad08b85387b41020f1fcc2d19e
testing commit 5fa4793a2d2d70ad08b85387b41020f1fcc2d19e gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: a6f2b305f647140df4cbed126f46e9679b0021b3652fd44a7ed3ff7fe0eefdd3
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: 2h49m52.984222252s (build: 1h27m15.624061347s, test: 1h14m32.11346645s)
crash still not fixed or there were kernel test errors
commit msg: Linux 6.6.119
crash: INFO: task hung in blkdev_put
INFO: task syz.2.17:3271 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.17 state:D stack:14232 pid:3271 ppid:2868 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x696/0x950 kernel/sched/core.c:6699
schedule+0x54/0xc0 kernel/sched/core.c:6773
schedule_preempt_disabled+0x32/0x50 kernel/sched/core.c:6832
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x44c/0x9d0 kernel/locking/mutex.c:747
blkdev_put+0x52/0x1b0 block/bdev.c:944
blkdev_release+0x26/0x30 block/fops.c:604
__fput+0x87/0x290 fs/file_table.c:384
task_work_run+0x7e/0xa0 kernel/task_work.c:239
get_signal+0x69/0x7a0 kernel/signal.c:2678
arch_do_signal_or_restart+0x89/0x260 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x6b/0xd0 kernel/entry/common.c:174
exit_to_user_mode_prepare+0x9c/0xe0 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x40 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f074678e9a9
RSP: 002b:00007f07475fa038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f07469b5fa0 RCX: 00007f074678e9a9
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007f0746810d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f07469b5fa0 R15: 00007ffdd6715f18
Showing all locks held in the system:
1 lock held by rcu_preempt/17:
#0: ffff888237c2e898 (&rq->__lock){....}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:558 [inline]
#0: ffff888237c2e898 (&rq->__lock){....}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1372 [inline]
#0: ffff888237c2e898 (&rq->__lock){....}-{2:2}, at: rq_lock kernel/sched/sched.h:1681 [inline]
#0: ffff888237c2e898 (&rq->__lock){....}-{2:2}, at: __schedule+0xae/0x950 kernel/sched/core.c:6613
1 lock held by khungtaskd/29:
#0: ffffffff8357bb48 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8357bb48 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8357bb48 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x2e/0x100 kernel/locking/lockdep.c:6633
2 locks held by kworker/u4:6/1116:
#0: ffff888237c2e898 (&rq->__lock){....}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:558 [inline]
#0: ffff888237c2e898 (&rq->__lock){....}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1372 [inline]
#0: ffff888237c2e898 (&rq->__lock){....}-{2:2}, at: rq_lock kernel/sched/sched.h:1681 [inline]
#0: ffff888237c2e898 (&rq->__lock){....}-{2:2}, at: __schedule+0xae/0x950 kernel/sched/core.c:6613
#1: ffffffff8357bb48 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#1: ffffffff8357bb48 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#1: ffffffff8357bb48 (rcu_read_lock){....}-{1:2}, at: __update_idle_core+0x1d/0xe0 kernel/sched/fair.c:7306
3 locks held by kworker/u5:1/1297:
#0: ffff88810a314938 ((wq_completion)hci2){....}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff88810a314938 ((wq_completion)hci2){....}-{0:0}, at: process_scheduled_works+0x26c/0x590 kernel/workqueue.c:2711
#1: ffffc90002e37e58 ((work_completion)(&hdev->cmd_sync_work)){....}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90002e37e58 ((work_completion)(&hdev->cmd_sync_work)){....}-{0:0}, at: process_scheduled_works+0x26c/0x590 kernel/workqueue.c:2711
#2: ffff888101b98e70 (&hdev->req_lock){....}-{3:3}, at: hci_cmd_sync_work+0xc2/0x190 net/bluetooth/hci_sync.c:326
2 locks held by getty/1404:
#0: ffff88810925d0a0 (&tty->ldisc_sem){....}-{0:0}, at: tty_ldisc_ref_wait+0x20/0x40 drivers/tty/tty_ldisc.c:243
#1: ffffc90002e3b2f0 (&ldata->atomic_read_lock){....}-{3:3}, at: n_tty_read+0x1a8/0x6d0 drivers/tty/n_tty.c:2217
1 lock held by udevd/2387:
#0: ffff888101af94c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0xb4/0x210 block/bdev.c:805
1 lock held by udevd/2407:
#0: ffff8881036a04c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0xb4/0x210 block/bdev.c:805
1 lock held by syz.2.17/3271:
#0: ffff888101af94c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x52/0x1b0 block/bdev.c:944
1 lock held by udevd/3275:
#0: ffff888101afbcc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0xb4/0x210 block/bdev.c:805
1 lock held by syz.3.23/3687:
#0: ffff888101afbcc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x52/0x1b0 block/bdev.c:944
1 lock held by udevd/4092:
#0: ffff888101afe4c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0xb4/0x210 block/bdev.c:805
1 lock held by syz.4.26/4095:
#0: ffff888101afe4c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x52/0x1b0 block/bdev.c:944
1 lock held by udevd/4099:
#0: ffff888101e80cc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0xb4/0x210 block/bdev.c:805
1 lock held by syz.5.48/4542:
#0: ffff888101e80cc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x52/0x1b0 block/bdev.c:944
1 lock held by udevd/4546:
#0: ffff888101e834c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0xb4/0x210 block/bdev.c:805
1 lock held by syz.6.53/4955:
#0: ffff888101e834c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x52/0x1b0 block/bdev.c:944
1 lock held by udevd/4960:
#0: ffff888101e85cc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0xb4/0x210 block/bdev.c:805
1 lock held by syz.7.57/5365:
#0: ffff888101e85cc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x52/0x1b0 block/bdev.c:944
1 lock held by syz.8.58/5769:
#0: ffff8881036a04c8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x52/0x1b0 block/bdev.c:944
1 lock held by udevd/6174:
#0: ffff8881036a2cc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_get_by_dev+0xb4/0x210 block/bdev.c:805
1 lock held by syz.9.62/6180:
#0: ffff8881036a2cc8 (&disk->open_mutex){....}-{3:3}, at: blkdev_put+0x52/0x1b0 block/bdev.c:944
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x78/0xc0 lib/dump_stack.c:106
nmi_cpu_backtrace+0x106/0x160 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x8e/0x130 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0x5dc/0x600 kernel/hung_task.c:379
kthread+0xe3/0x100 kernel/kthread.c:388
ret_from_fork+0x2f/0x40 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 1116 Comm: kworker/u4:6 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline]
RIP: 0010:smp_call_function_many_cond+0x43f/0x600 kernel/smp.c:855
Code: 0f bc 5c 24 40 f7 c3 f8 ff ff ff 75 3b 89 d8 83 e0 07 48 8b 3c c5 30 18 12 83 49 03 3e 66 90 f7 47 08 01 00 00 00 74 09 f3 90 <8b> 47 08 a8 01 75 f7 ff c3 83 e3 0f 83 fb 08 72 a9 eb 0b f3 0f 1e
RSP: 0018:ffffc900025f3c88 EFLAGS: 00000202
RAX: 0000000000000011 RBX: 0000000000000001 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff82fa5768 RDI: ffff888237d34040
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000034
R10: 0000000000000006 R11: 0000000000000000 R12: 0000000000000002
R13: ffff888237d34040 R14: ffff888237c2f940 R15: ffffffff810383e0
FS: 0000000000000000(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb326ff7f98 CR3: 0000000003442000 CR4: 00000000003506f0
Call Trace:
on_each_cpu_cond_mask+0x3a/0x60 kernel/smp.c:1022
on_each_cpu include/linux/smp.h:71 [inline]
text_poke_sync arch/x86/kernel/alternative.c:2222 [inline]
text_poke_bp_batch+0x291/0x2e0 arch/x86/kernel/alternative.c:-1
text_poke_flush arch/x86/kernel/alternative.c:2623 [inline]
text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:2630
arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked kernel/jump_label.c:207 [inline]
static_key_enable+0x40/0x60 kernel/jump_label.c:220
toggle_allocation_gate+0x3c/0x130 mm/kfence/core.c:831
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0x2c8/0x590 kernel/workqueue.c:2711
worker_thread+0x23e/0x300 kernel/workqueue.c:2792
kthread+0xe3/0x100 kernel/kthread.c:388
ret_from_fork+0x2f/0x40 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293