ci starts bisection 2026-01-08 09:47:44.355219175 +0000 UTC m=+3707253.880705315
bisecting fixing commit since 89be9a83ccf1f88522317ce02f854f30d6115c41
building syzkaller on 0b3788a098c8428ff028bb00ac450cf9b726b7f6
ensuring issue is reproducible on original commit 89be9a83ccf1f88522317ce02f854f30d6115c41

testing commit 89be9a83ccf1f88522317ce02f854f30d6115c41 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: 089b3b2252aa351a5d63ce0658513e8f7b7e3892dec17b66dc0a8ba1037ff506
run #0: crashed: INFO: rcu detected stall in worker_thread
run #1: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #2: crashed: INFO: rcu detected stall in sys_close
run #3: crashed: INFO: rcu detected stall in sock_write_iter
run #4: crashed: INFO: rcu detected stall in do_idle
run #5: crashed: INFO: rcu detected stall in worker_thread
run #6: crashed: INFO: rcu detected stall in do_idle
run #7: crashed: INFO: rcu detected stall in call_usermodehelper_exec_async
run #8: crashed: INFO: rcu detected stall in sys_socket
run #9: crashed: INFO: rcu detected stall in sys_rename
run #10: crashed: INFO: rcu detected stall in security_file_open
run #11: crashed: INFO: rcu detected stall in rtnl_newlink
run #12: crashed: INFO: rcu detected stall in rtnl_newlink
run #13: crashed: INFO: rcu detected stall in rtnl_newlink
run #14: crashed: INFO: rcu detected stall in worker_thread
run #15: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #16: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #17: crashed: INFO: rcu detected stall in inet_rtm_newaddr
run #18: crashed: INFO: rcu detected stall in inet6_rtm_newaddr
run #19: crashed: no output from test machine
representative crash: INFO: rcu detected stall in worker_thread, types: [HANG]
check whether we can drop unnecessary instrumentation
disabling configs for [memleak ubsan bug_or_warning kasan locking atomic_sleep], they are not needed
testing commit 89be9a83ccf1f88522317ce02f854f30d6115c41 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: afcc1e80bf13f15754490bac92c351b174213cb846d6abda3d9baa46cb9559f1
run #0: crashed: INFO: rcu detected stall in corrupted
run #1: crashed: INFO: rcu detected stall in sys_clone
run #2: crashed: INFO: rcu detected stall in worker_thread
run #3: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #4: crashed: INFO: rcu detected stall in sys_sendto
run #5: crashed: INFO: rcu detected stall in inet6_rtm_newaddr
run #6: crashed: INFO: rcu detected stall in vms_gather_munmap_vmas
run #7: crashed: INFO: rcu detected stall in worker_thread
run #8: crashed: INFO: rcu detected stall in sys_getsockopt
run #9: crashed: no output from test machine
representative crash: INFO: rcu detected stall in corrupted, types: [HANG]
the bug reproduces without the instrumentation
disabling configs for [kasan locking atomic_sleep memleak ubsan bug_or_warning], they are not needed
kconfig minimization: base=4109 full=8473 leaves diff=2203
split chunks (needed=false): <2203>
split chunk #0 of len 2203 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 89be9a83ccf1f88522317ce02f854f30d6115c41 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: cbd186a3f6c391d911d34c693c8be9f258740a583160a8a1856a7ae243b9db94
run #0: crashed: INFO: rcu detected stall in corrupted
run #1: crashed: INFO: rcu detected stall in smp_call_function
run #2: crashed: INFO: rcu detected stall in x64_sys_call
run #3: crashed: INFO: rcu detected stall in corrupted
run #4: crashed: INFO: rcu detected stall in corrupted
run #5: crashed: INFO: rcu detected stall in worker_thread
run #6: crashed: INFO: rcu detected stall in worker_thread
run #7: crashed: INFO: rcu detected stall in corrupted
run #8: OK
run #9: OK
representative crash: INFO: rcu detected stall in corrupted, types: [HANG]
the chunk can be dropped
testing without sub-chunk 2/5
disabling configs for [atomic_sleep memleak ubsan bug_or_warning kasan locking], they are not needed
testing commit 89be9a83ccf1f88522317ce02f854f30d6115c41 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: 38bafc42cfb39c564c21ac8b3cbef61dbbf009501e5033b477be151753866d34
run #0: crashed: INFO: rcu detected stall in corrupted
run #1: crashed: INFO: rcu detected stall in corrupted
run #2: crashed: INFO: rcu detected stall in corrupted
run #3: crashed: INFO: rcu detected stall in worker_thread
run #4: crashed: INFO: rcu detected stall in corrupted
run #5: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #6: crashed: INFO: rcu detected stall in rtnetlink_rcv_msg
run #7: crashed: INFO: rcu detected stall in worker_thread
run #8: crashed: INFO: rcu detected stall in rtnl_newlink
run #9: crashed: no output from test machine
representative crash: INFO: rcu detected stall in corrupted, types: [HANG]
the chunk can be dropped
testing without sub-chunk 3/5
disabling configs for [kasan locking atomic_sleep memleak ubsan bug_or_warning], they are not needed
testing commit 89be9a83ccf1f88522317ce02f854f30d6115c41 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: 71f1cd02a726d972295a9afc2181db579eb9e93bfbfa769e40a4a572039ab536
all runs: OK
false negative chance: 0.000
testing without sub-chunk 4/5
disabling configs for [locking atomic_sleep memleak ubsan bug_or_warning kasan], they are not needed
testing commit 89be9a83ccf1f88522317ce02f854f30d6115c41 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: 971bcd5ea554dcb7c5b401a81dcba6a1251882594809dc985ad2ace71460e574
run #0: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #1: crashed: INFO: rcu detected stall in vms_complete_munmap_vmas
run #2: crashed: INFO: rcu detected stall in sys_clone
run #3: crashed: INFO: rcu detected stall in sys_mprotect
run #4: crashed: INFO: rcu detected stall in corrupted
run #5: crashed: INFO: rcu detected stall in corrupted
run #6: crashed: INFO: rcu detected stall in do_idle
run #7: crashed: INFO: rcu detected stall in corrupted
run #8: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #9: OK
representative crash: INFO: rcu detected stall in tc_modify_qdisc, types: [HANG]
the chunk can be dropped
testing without sub-chunk 5/5
disabling configs for [memleak ubsan bug_or_warning kasan locking atomic_sleep], they are not needed
testing commit 89be9a83ccf1f88522317ce02f854f30d6115c41 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: e9e1c98d92b8ec4b077722d619e8b48e0ea2fcb7365f7b1c27d1e3bcf433e6d0
run #0: crashed: INFO: rcu detected stall in newfstatat
run #1: crashed: INFO: rcu detected stall in filemap_fault
run #2: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #3: crashed: INFO: rcu detected stall in sys_openat
run #4: crashed: INFO: rcu detected stall in corrupted
run #5: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #6: crashed: INFO: rcu detected stall in x64_sys_call
run #7: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #8: crashed: INFO: rcu detected stall in filemap_read
run #9: OK
representative crash: INFO: rcu detected stall in newfstatat, types: [HANG]
the chunk can be dropped
minimized to 441 configs; suspects: [AX25 BRIDGE BRIDGE_NETFILTER CAN CFG80211 CHECKPOINT_RESTORE DVB_CORE FB_CORE HAMRADIO HID_LOGITECH HSR INFINIBAND INFINIBAND_ADDR_TRANS INFINIBAND_USER_ACCESS INPUT_JOYSTICK INPUT_MOUSE IP6_NF_MANGLE IP6_NF_RAW IPV6_MROUTE IPV6_MULTIPLE_TABLES IPV6_OPTIMISTIC_DAD IPV6_PIMSM_V2 IPV6_ROUTER_PREF IPV6_ROUTE_INFO IPV6_RPL_LWTUNNEL IPV6_SEG6_BPF IPV6_SEG6_HMAC IPV6_SEG6_LWTUNNEL IPV6_SIT_6RD IPV6_SUBTREES IPV6_TUNNEL IPV6_VTI IPVLAN IPVLAN_L3S IPVTAP IP_FIB_TRIE_STATS IP_MROUTE_MULTIPLE_TABLES IP_NF_ARPFILTER IP_NF_ARPTABLES IP_NF_ARP_MANGLE IP_NF_FILTER IP_NF_IPTABLES_LEGACY IP_NF_MANGLE IP_NF_MATCH_AH IP_NF_MATCH_ECN IP_NF_MATCH_RPFILTER IP_NF_MATCH_TTL IP_NF_NAT IP_NF_RAW IP_NF_SECURITY IP_NF_TARGET_ECN IP_NF_TARGET_MASQUERADE IP_NF_TARGET_NETMAP IP_NF_TARGET_REDIRECT IP_NF_TARGET_REJECT IP_NF_TARGET_SYNPROXY IP_NF_TARGET_TTL IP_ROUTE_CLASSID IP_SET IP_SET_BITMAP_IP IP_SET_BITMAP_IPMAC IP_SET_BITMAP_PORT IP_SET_HASH_IP IP_SET_HASH_IPMAC IP_SET_HASH_IPMARK IP_SET_HASH_IPPORT IP_SET_HASH_IPPORTIP IP_SET_HASH_IPPORTNET IP_SET_HASH_MAC IP_SET_HASH_NET IP_SET_HASH_NETIFACE IP_SET_HASH_NETNET IP_SET_HASH_NETPORT IP_SET_HASH_NETPORTNET IP_SET_LIST_SET IP_VS IP_VS_DH IP_VS_FO IP_VS_FTP IP_VS_IPV6 IP_VS_LBLC IP_VS_LBLCR IP_VS_LC IP_VS_MH IP_VS_NFCT IP_VS_NQ IP_VS_OVF IP_VS_PE_SIP IP_VS_PROTO_AH IP_VS_PROTO_AH_ESP IP_VS_PROTO_ESP IP_VS_PROTO_SCTP IP_VS_PROTO_TCP IP_VS_PROTO_UDP IP_VS_RR IP_VS_SED IP_VS_SH IP_VS_TWOS IP_VS_WLC IP_VS_WRR IRQ_BYPASS_MANAGER IRQ_POLL IR_IGORPLUGUSB IR_IGUANA IR_IMON IR_IMON_RAW IR_MCEUSB IR_REDRAT3 IR_STREAMZAP IR_TOY IR_TTUSBIR ISDN ISDN_CAPI JFFS2_CMODE_PRIORITY JFFS2_COMPRESSION_OPTIONS JFFS2_FS JFFS2_FS_POSIX_ACL JFFS2_FS_SECURITY JFFS2_FS_WRITEBUFFER JFFS2_FS_XATTR JFFS2_LZO JFFS2_RTIME JFFS2_RUBIN JFFS2_SUMMARY JFFS2_ZLIB JFS_DEBUG JFS_FS JFS_POSIX_ACL JFS_SECURITY JOYSTICK_IFORCE JOYSTICK_IFORCE_USB JOYSTICK_PXRC JOYSTICK_XPAD JOYSTICK_XPAD_FF JOYSTICK_XPAD_LEDS KARMA_PARTITION KCOV KCOV_ENABLE_COMPARISONS KCOV_INSTRUMENT_ALL KEYS_REQUEST_CACHE KEY_DH_OPERATIONS KEY_NOTIFICATIONS KSM KVM KVM_AMD KVM_ASYNC_PF KVM_COMMON KVM_COMPAT KVM_ELIDE_TLB_FLUSH_IF_YOUNG KVM_GENERIC_DIRTYLOG_READ_PROTECT KVM_GENERIC_HARDWARE_ENABLING KVM_GENERIC_MEMORY_ATTRIBUTES KVM_GENERIC_MMU_NOTIFIER KVM_GENERIC_PRE_FAULT_MEMORY KVM_GENERIC_PRIVATE_MEM KVM_HYPERV KVM_MMIO KVM_MMU_LOCKLESS_AGING KVM_PRIVATE_MEM KVM_PROVE_MMU KVM_SW_PROTECTED_VM KVM_VFIO KVM_X86 KVM_XEN KVM_XFER_TO_GUEST_WORK L2TP L2TP_ETH L2TP_IP L2TP_V3 LAPB LAPBETHER LDM_PARTITION LEDS_CLASS_MULTICOLOR LEGACY_PTYS LIBNVDIMM LINEAR_RANGES LLC LLC2 LOGIG940_FF LOGIRUMBLEPAD2_FF LOGITECH_FF LOGIWHEELS_FF LOGO LOGO_LINUX_MONO LOGO_LINUX_VGA16 LPC_ICH LWTUNNEL LWTUNNEL_BPF LZ4HC_COMPRESS LZ4_COMPRESS MAC80211 MAC80211_HAS_RC MAC80211_HWSIM MAC80211_MESH MAC80211_RC_DEFAULT_MINSTREL MAC80211_RC_MINSTREL MACSEC MACVLAN MACVTAP MAC_PARTITION MAPPING_DIRTY_HELPERS MCTP MDIO_MVUSB MD_RAID0 MD_RAID1 MD_RAID10 MD_RAID456 MEDIA_ANALOG_TV_SUPPORT MEDIA_ATTACH MEDIA_CONTROLLER MEDIA_CONTROLLER_DVB MEDIA_DIGITAL_TV_SUPPORT MEDIA_RADIO_SUPPORT MEDIA_SDR_SUPPORT MEDIA_SUPPORT MEDIA_SUPPORT_FILTER MEDIA_TUNER MEDIA_TUNER_MSI001 MEMORY_BALLOON MEMORY_HOTPLUG MEMORY_ISOLATION MEMREGION MEMSTICK MEMSTICK_REALTEK_USB MEM_SOFT_DIRTY MFD_CORE MFD_SYSCON MHI_BUS MHI_WWAN_CTRL MHP_DEFAULT_ONLINE_TYPE_ONLINE_AUTO MHP_MEMMAP_ON_MEMORY MICROCHIP_PHY MINIX_FS MINIX_SUBPARTITION MIN_HEAP MISC_RTSX MISC_RTSX_USB MISDN MISDN_DSP MISDN_HFCUSB MISDN_L1OIP MKISS MLX4_CORE MLX4_INFINIBAND MMC MMC_REALTEK_USB MMC_USHC MMC_VUB300 MM_ID MODULE_SRCVERSION_ALL MOST MOST_USB_HDM MOUSE_APPLETOUCH MOUSE_BCM5974 MOUSE_PS2 MOUSE_PS2_ALPS MOUSE_PS2_BYD MOUSE_PS2_CYPRESS MOUSE_PS2_FOCALTECH MOUSE_PS2_LIFEBOOK MOUSE_PS2_LOGIPS2PP MOUSE_PS2_SMBUS MOUSE_PS2_SYNAPTICS MOUSE_PS2_SYNAPTICS_SMBUS MOUSE_PS2_TRACKPOINT MOUSE_SYNAPTICS_USB MPLS MPLS_IPTUNNEL MPLS_ROUTING MPTCP MPTCP_IPV6 MRP MTD MTD_BLKDEVS MTD_BLOCK MTD_BLOCK2MTD MTD_CFI_I1 MTD_CFI_I2 MTD_MAP_BANK_WIDTH_1 MTD_MAP_BANK_WIDTH_2 MTD_MAP_BANK_WIDTH_4 MTD_MTDRAM MTD_PHRAM MTD_SLRAM MUSB_PIO_ONLY ND_BTT ND_CLAIM ND_PFN NETDEVSIM NETFILTER_ADVANCED NETFILTER_BPF_LINK NETFILTER_FAMILY_ARP NETFILTER_FAMILY_BRIDGE NETFILTER_NETLINK_ACCT NETFILTER_NETLINK_OSF NETFILTER_NETLINK_QUEUE NETFILTER_SYNPROXY NETFILTER_XTABLES_COMPAT NETFILTER_XT_CONNMARK NETFILTER_XT_MATCH_BPF NETFILTER_XT_MATCH_CGROUP NETFILTER_XT_MATCH_CLUSTER NETFILTER_XT_MATCH_COMMENT NETFILTER_XT_MATCH_CONNBYTES NETFILTER_XT_MATCH_CONNLABEL NETFILTER_XT_MATCH_CONNLIMIT NETFILTER_XT_MATCH_CONNMARK NETFILTER_XT_MATCH_CPU NETFILTER_XT_MATCH_DCCP NETFILTER_XT_MATCH_DEVGROUP NETFILTER_XT_MATCH_DSCP NETFILTER_XT_MATCH_ECN NETFILTER_XT_MATCH_ESP NETFILTER_XT_MATCH_HASHLIMIT NETFILTER_XT_MATCH_HELPER NETFILTER_XT_MATCH_HL NETFILTER_XT_MATCH_IPCOMP NETFILTER_XT_MATCH_IPRANGE NETFILTER_XT_MATCH_IPVS NETFILTER_XT_MATCH_L2TP NETFILTER_XT_MATCH_LENGTH NETFILTER_XT_MATCH_LIMIT NETFILTER_XT_MATCH_MAC NETFILTER_XT_MATCH_MARK NETFILTER_XT_MATCH_MULTIPORT NETFILTER_XT_MATCH_NFACCT NETFILTER_XT_MATCH_OSF NETFILTER_XT_MATCH_OWNER NETFILTER_XT_MATCH_PHYSDEV NETFILTER_XT_MATCH_PKTTYPE NETFILTER_XT_MATCH_QUOTA NETFILTER_XT_MATCH_RATEEST NETFILTER_XT_MATCH_REALM NETFILTER_XT_MATCH_RECENT NETFILTER_XT_MATCH_SCTP NETFILTER_XT_MATCH_SOCKET NETFILTER_XT_MATCH_STATISTIC NETFILTER_XT_MATCH_STRING NETFILTER_XT_MATCH_TCPMSS NETFILTER_XT_MATCH_TIME NETFILTER_XT_MATCH_U32 NETFILTER_XT_NAT NETFILTER_XT_SET NETFILTER_XT_TARGET_AUDIT NETFILTER_XT_TARGET_CHECKSUM NETFILTER_XT_TARGET_CLASSIFY NETFILTER_XT_TARGET_CONNMARK NETFILTER_XT_TARGET_CT NETFILTER_XT_TARGET_DSCP NETFILTER_XT_TARGET_HL NETFILTER_XT_TARGET_HMARK NETFILTER_XT_TARGET_IDLETIMER NETFILTER_XT_TARGET_LED NETFILTER_XT_TARGET_MARK NETFILTER_XT_TARGET_NETMAP NETFILTER_XT_TARGET_NFQUEUE NETFILTER_XT_TARGET_NOTRACK NETFILTER_XT_TARGET_RATEEST NETFILTER_XT_TARGET_REDIRECT NETFILTER_XT_TARGET_TCPOPTSTRIP NETFILTER_XT_TARGET_TEE NETFILTER_XT_TARGET_TPROXY NETFILTER_XT_TARGET_TRACE NETLINK_DIAG NETROM NET_9P_RDMA NET_ACT_BPF NET_ACT_CONNMARK NET_ACT_CSUM NET_ACT_CT NET_ACT_CTINFO NET_ACT_GATE NET_ACT_IFE NET_ACT_MPLS NET_ACT_NAT NET_ACT_PEDIT NET_ACT_POLICE NET_ACT_SAMPLE NET_ACT_SIMP NET_ACT_SKBEDIT NET_ACT_SKBMOD NET_ACT_TUNNEL_KEY NET_ACT_VLAN NET_CLS_BASIC NET_CLS_BPF NET_CLS_FLOW NET_CLS_FLOWER NET_CLS_FW NET_CLS_MATCHALL NET_CLS_ROUTE4 NET_CRC32C NET_DEVLINK NET_DROP_MONITOR NET_DSA NET_DSA_TAG_BRCM NET_DSA_TAG_BRCM_COMMON NET_DSA_TAG_BRCM_PREPEND NET_DSA_TAG_MTK NET_DSA_TAG_QCA NET_DSA_TAG_RTL4_A NET_EMATCH_CANID NET_EMATCH_CMP NET_EMATCH_IPSET NET_EMATCH_IPT NET_EMATCH_META NET_EMATCH_NBYTE NET_EMATCH_TEXT NET_EMATCH_U32 NET_FC NET_FOU NET_FOU_IP_TUNNELS NET_IFE NET_IFE_SKBMARK NET_IFE_SKBPRIO NET_IFE_SKBTCINDEX NET_IPGRE NET_IPGRE_BROADCAST NET_IPGRE_DEMUX NET_IPIP NET_IPVTI NET_KEY NET_KEY_MIGRATE NET_L3_MASTER_DEV NET_MPLS_GSO NET_NCSI NET_NSH NET_REDIRECT NET_SCH_CAKE NET_SCH_CBS NET_SCH_CHOKE NET_SCH_CODEL NET_SCH_DRR NET_SCH_ETF NET_SCH_ETS NET_SCH_FQ NET_SCH_FQ_CODEL NET_SCH_FQ_PIE NET_SCH_GRED NET_SCH_HFSC NET_SCH_HHF NET_SCH_HTB NET_SCH_INGRESS NET_SCH_MQPRIO NET_SCH_MQPRIO_LIB NET_SCH_MULTIQ NET_SCH_NETEM NET_SCH_PIE NET_SCH_PLUG NET_SCH_PRIO NET_SCH_QFQ NET_SCH_RED NET_SCH_SFB NET_SCH_SFQ NET_SCH_SKBPRIO NET_SCH_TAPRIO NET_SCH_TBF NET_SCH_TEQL NET_SHAPER NET_SOCK_MSG NET_SWITCHDEV NET_TC_SKB_EXT NET_TEAM NET_TEAM_MODE_ACTIVEBACKUP NET_TEAM_MODE_BROADCAST NET_TEAM_MODE_LOADBALANCE NET_TEAM_MODE_RANDOM NET_TEAM_MODE_ROUNDROBIN NET_UDP_TUNNEL NET_VRF NFC NFC_DIGITAL NFC_FDP NFC_HCI NFC_MRVL NFC_MRVL_USB NFC_NCI NFC_NCI_UART NFC_PN533 NFC_PN533_USB NFC_PORT100 NFC_SHDLC NFC_SIM NFC_VIRTUAL_NCI NFSD NFSD_BLOCKLAYOUT NFSD_FLEXFILELAYOUT NFSD_PNFS NFSD_SCSILAYOUT NFSD_V3_ACL NFSD_V4 NFSD_V4_2_INTER_SSC NFSD_V4_SECURITY_LABEL NFS_FSCACHE NFS_V4_1 NFS_V4_2 NFS_V4_2_READ_PLUS NFS_V4_2_SSC_HELPER NFS_V4_SECURITY_LABEL NFT_BRIDGE_META NFT_BRIDGE_REJECT NFT_COMPAT NFT_COMPAT_ARP NFT_CONNLIMIT NFT_CT NFT_DUP_IPV4 NFT_DUP_IPV6 NFT_DUP_NETDEV NFT_FIB NFT_FIB_INET NFT_FIB_IPV4 NFT_FIB_IPV6 NFT_FIB_NETDEV NFT_FLOW_OFFLOAD NFT_HASH NFT_LIMIT NFT_LOG NFT_MASQ NFT_NAT NFT_NUMGEN NFT_OSF NFT_QUEUE NFT_QUOTA NFT_REDIR NFT_REJECT NFT_REJECT_INET NFT_REJECT_IPV4 NFT_REJECT_IPV6 NFT_REJECT_NETDEV NFT_SOCKET NFT_SYNPROXY NFT_TPROXY NFT_TUNNEL NFT_XFRM NF_CONNTRACK_AMANDA NF_CONNTRACK_BRIDGE NF_CONNTRACK_BROADCAST NF_CONNTRACK_EVENTS NF_CONNTRACK_H323 NF_CONNTRACK_MARK NF_FLOW_TABLE NF_TABLES NF_TABLES_ARP NF_TABLES_BRIDGE NF_TABLES_INET NF_TABLES_IPV4 NF_TABLES_IPV6 NF_TABLES_NETDEV PARTITION_ADVANCED PSAMPLE RC_CORE RC_DEVICES RFKILL SPI USB_GADGET USB_MUSB_HDRC VIDEO_DEV WAN WATCH_QUEUE WIRELESS WLAN WWAN X25]
disabling configs for [atomic_sleep memleak ubsan bug_or_warning kasan locking], they are not needed
testing current HEAD f0b9d8eb98dfee8d00419aa07543bdc2c1a44fb1
testing commit f0b9d8eb98dfee8d00419aa07543bdc2c1a44fb1 gcc
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
kernel signature: 92ac729d89e2720beafe2cb2aca3fba880d14d0fa74379ece19ffda44fa468be
run #0: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #1: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #2: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #3: crashed: INFO: rcu detected stall in corrupted
run #4: crashed: INFO: rcu detected stall in tc_modify_qdisc
run #5: crashed: INFO: rcu detected stall in kthread_worker_fn
run #6: crashed: INFO: rcu detected stall in worker_thread
run #7: crashed: no output from test machine
run #8: crashed: no output from test machine
run #9: crashed: no output from test machine
representative crash: INFO: rcu detected stall in tc_modify_qdisc, types: [HANG UNKNOWN]
crash still not fixed/happens on the oldest tested release
revisions tested: 8, total time: 4h17m28.496059603s (build: 2h52m13.842717199s, test: 1h9m32.79664867s)
crash still not fixed or there were kernel test errors
commit msg: Merge tag 'nfsd-6.19-3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux
crash: INFO: rcu detected stall in tc_modify_qdisc
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=204c/1/0x4000000000000000 softirq=6442/6446 fqs=302
rcu: 	(detected by 0, t=10006 jiffies, g=7933, q=99 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5727 Comm: syz.2.18 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x1a/0x40 kernel/rcu/tree.c:751
Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 65 ff 05 35 3c e6 03 e8 70 91 da 01 89 c0 48 8b 04 c5 10 1c c9 83 <8b> 80 98 55 35 85 65 ff 0d 19 3c e6 03 74 0c 83 e0 04 c1 e8 02 e9
RSP: 0018:ffffc900000e0ef8 EFLAGS: 00000002
RAX: ffff8882b29d0000 RBX: ffff888237d1be01 RCX: 0000000080010001
RDX: 0000000000010000 RSI: ffffffff83b47491 RDI: ffffffff83c6c2db
RBP: ffff888237d1bf80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff829d5380 R12: ffff888237d1be80
R13: ffffffff829d5380 R14: 0000000000000002 R15: ffff888105bff300
FS:  00007fb2eb0ef6c0(0000) GS:ffff8882b29d0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc003723e9c CR3: 000000011f39c000 CR4: 00000000003506f0
Call Trace:
 <IRQ>
 trace_hrtimer_expire_entry include/trace/events/timer.h:259 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1774 [inline]
 __hrtimer_run_queues+0x1eb/0x510 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x13e/0x2c0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x84/0x200 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x8d/0xb0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lockdep_unregister_key+0x2e5/0x320 kernel/locking/lockdep.c:6616
Code: a1 02 00 74 5a 89 c6 48 c7 c7 f0 df 18 89 e8 12 2b e0 01 90 e9 2a fe ff ff e8 97 0f df 01 41 f7 c6 00 02 00 00 74 aa fb 84 db <75> a9 eb ba 90 e8 f1 a2 93 00 90 eb 88 90 e8 e8 a2 93 00 90 e9 d8
RSP: 0018:ffffc90001d8f788 EFLAGS: 00000246
RAX: 0000000000000046 RBX: ffff888105bf9a00 RCX: 0000000000000046
RDX: ffffffff8578db98 RSI: ffffffff83b474cf RDI: ffffffff83bbbec4
RBP: ffff888105bf9a69 R08: 0000000000000000 R09: 0000000000000007
R10: 0000000000000000 R11: ffffffff8294bc20 R12: 0000000000001000
R13: ffff8881083b9bc0 R14: 0000000000000246 R15: 0000000000000000
 __qdisc_destroy+0x6b/0x1e0 net/sched/sch_generic.c:1079
 taprio_attach+0x116/0x1a0 net/sched/sch_taprio.c:2161
 qdisc_graft+0x949/0xa90 net/sched/sch_api.c:1162
 __tc_modify_qdisc net/sched/sch_api.c:1761 [inline]
 tc_modify_qdisc+0xc9d/0x1040 net/sched/sch_api.c:1817
 rtnetlink_rcv_msg+0x586/0x610 net/core/rtnetlink.c:6967
 netlink_rcv_skb+0x16d/0x240 net/netlink/af_netlink.c:2550
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x3ca/0x490 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x494/0x590 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0xc9/0xf0 net/socket.c:742
 ____sys_sendmsg+0x257/0x360 net/socket.c:2592
 ___sys_sendmsg+0x2de/0x320 net/socket.c:2646
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2683 [inline]
 __se_sys_sendmsg net/socket.c:2681 [inline]
 __x64_sys_sendmsg+0x110/0x1a0 net/socket.c:2681
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x85/0x2e0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb2eb67e9a9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb2eb0ef038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fb2eb8a5fa0 RCX: 00007fb2eb67e9a9
RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 0000000000000006
RBP: 00007fb2eb700d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb2eb8a5fa0 R15: 00007ffd24f97158
 </TASK>
rcu: rcu_preempt kthread starved for 8495 jiffies! g7933 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:14496 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x94d/0xe50 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xac/0x140 kernel/sched/core.c:6960
 schedule_timeout+0x106/0x190 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x19e/0x670 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x1c/0x150 kernel/rcu/tree.c:2285
 kthread+0x2bd/0x300 kernel/kthread.c:463
 ret_from_fork+0x1a6/0x380 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 3609 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x64f/0xb30 kernel/smp.c:877
Code: 75 00 66 90 41 8b 6e 08 89 ee 83 e6 01 31 ff e8 77 77 05 00 83 e5 01 75 07 e8 2d 73 05 00 eb 18 f3 90 41 f7 46 08 01 00 00 00 <74> 07 e8 1a 73 05 00 eb ed e8 13 73 05 00 4c 89 e5 ff c3 83 e3 0f
RSP: 0018:ffffc90001b8f950 EFLAGS: 00000202
RAX: ffffffff8154b2c6 RBX: 0000000000000001 RCX: ffff888121ab8000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000192
R10: 0000000000000000 R11: ffffffff813df8f0 R12: ffff888237c2c400
R13: ffff888237d30d60 R14: ffff888237d30d60 R15: 00000000fffffff8
FS:  0000000000000000(0000) GS:ffff8882b28d0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555576c874a8 CR3: 0000000003e7a000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline]
 flush_tlb_mm_range+0x265/0x630 arch/x86/mm/tlb.c:1472
 tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline]
 tlb_flush_mmu+0x12a/0x370 mm/mmu_gather.c:403
 tlb_finish_mmu+0x5d/0xb0 mm/mmu_gather.c:497
 free_ldt_pgtables arch/x86/kernel/ldt.c:411 [inline]
 ldt_arch_exit_mmap+0x133/0x160 arch/x86/kernel/ldt.c:499
 arch_exit_mmap arch/x86/include/asm/mmu_context.h:234 [inline]
 exit_mmap+0x1b2/0x710 mm/mmap.c:1263
 __mmput+0x70/0x190 kernel/fork.c:1173
 exit_mm+0xbf/0x160 kernel/exit.c:581
 do_exit+0x2f0/0xf90 kernel/exit.c:959
 do_group_exit+0xb2/0xf0 kernel/exit.c:1112
 get_signal+0xc5a/0xd90 kernel/signal.c:3034
 arch_do_signal_or_restart+0x96/0x450 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x83/0x4d0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x188/0x2e0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb2eb674bd3
Code: Unable to access opcode bytes at 0x7fb2eb674ba9.
RSP: 002b:00007ffd24f976a8 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000000000000e1a RCX: 00007fb2eb674bd3
RDX: 0000000040000000 RSI: 00007ffd24f976bc RDI: 00000000ffffffff
RBP: 00007ffd24f976bc R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffd24f97740
R13: 00007ffd24f97748 R14: 0000000000000009 R15: 0000000000000000
 </TASK>