Greeting, FYI, we noticed the following commit (built with gcc-9): commit: b77e315a96445e5f19a83546c73d2abbcedfa5db ("io_uring: avoid ring quiesce while registering/unregistering eventfd") linux-devel devel-catchup-20220206-211654 in testcase: trinity version: trinity-static-x86_64-x86_64-1c734c75-1_2020-01-06 with following parameters: runtime: 300s test-description: Trinity is a linux system call fuzz tester. test-url: http://codemonkey.org.uk/projects/trinity/ on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): +------------------------------------------------------------+------------+------------+ | | 054f8098d9 | b77e315a96 | +------------------------------------------------------------+------------+------------+ | WARNING:suspicious_RCU_usage | 0 | 12 | | fs/io_uring.c:#suspicious_rcu_dereference_protected()usage | 0 | 12 | +------------------------------------------------------------+------------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot <oliver.sang(a)intel.com&gt; [ 442.754082][ T7] WARNING: suspicious RCU usage [ 442.755607][ T7] 5.17.0-rc2-00169-gb77e315a9644 #1 Not tainted [ 442.757434][ T7] ----------------------------- [ 442.758944][ T7] fs/io_uring.c:9421 suspicious rcu_dereference_protected() usage! [ 442.761272][ T7] [ 442.761272][ T7] other info that might help us debug this: [ 442.761272][ T7] [ 442.764360][ T7] [ 442.764360][ T7] rcu_scheduler_active = 2, debug_locks = 1 [ 442.766863][ T7] 2 locks held by kworker/u2:1/7: [ 442.768373][ T7] #0: ffff888100048f30 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work (arch/x86/include/asm/atomic64_64.h:34 include/linux/atomic/atomic-long.h:41 include/linux/atomic/atomic-instrumented.h:1280 kernel/workqueue.c:631 kernel/workqueue.c:658 kernel/workqueue.c:2278) [ 442.771699][ T7] #1: ffffc90000043e50 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work (arch/x86/include/asm/atomic64_64.h:34 include/linux/atomic/atomic-long.h:41 include/linux/atomic/atomic-instrumented.h:1280 kernel/workqueue.c:631 kernel/workqueue.c:658 kernel/workqueue.c:2278) [ 442.775227][ T7] [ 442.775227][ T7] stack backtrace: [ 442.777250][ T7] CPU: 0 PID: 7 Comm: kworker/u2:1 Not tainted 5.17.0-rc2-00169-gb77e315a9644 #1 [ 442.780127][ T7] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 442.783010][ T7] Workqueue: events_unbound io_ring_exit_work [ 442.784990][ T7] Call Trace: [ 442.786120][ T7] <TASK> [ 442.787197][ T7] dump_stack_lvl (lib/dump_stack.c:108) [ 442.788669][ T7] dump_stack (lib/dump_stack.c:114) [ 442.790028][ T7] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6564) [ 442.791808][ T7] io_eventfd_unregister (fs/io_uring.c:9421 (discriminator 5)) [ 442.793402][ T7] io_ring_ctx_free (fs/io_uring.c:9437 fs/io_uring.c:9492) [ 442.794954][ T7] io_ring_exit_work (fs/io_uring.c:9669) [ 442.796474][ T7] ? io_uring_del_tctx_node (fs/io_uring.c:9581) [ 442.798191][ T7] process_one_work (arch/x86/include/asm/jump_label.h:27 include/linux/jump_label.h:212 include/trace/events/workqueue.h:108 kernel/workqueue.c:2312) [ 442.799764][ T7] ? process_one_work (kernel/workqueue.c:2397) [ 442.801266][ T7] worker_thread (include/linux/list.h:292 kernel/workqueue.c:2455) [ 442.802712][ T7] ? process_one_work (kernel/workqueue.c:2397) [ 442.804217][ T7] kthread (kernel/kthread.c:377) [ 442.805543][ T7] ? kthread_complete_and_exit (kernel/kthread.c:332) [ 442.807280][ T7] ret_from_fork (arch/x86/entry/entry_64.S:301) [ 442.808639][ T7] </TASK> [ 459.159532][ T1106] futex_wake_op: trinity-c0 tries to shift op by -1; fix this program [ 472.545875][ T1240] futex_wake_op: trinity-c2 tries to shift op by -1; fix this program [ 473.540073][ T1106] ======================================================= [ 473.540073][ T1106] WARNING: The mand mount option has been deprecated and [ 473.540073][ T1106] and is ignored by this kernel. Remove the mand [ 473.540073][ T1106] option from the mount to silence this warning. [ 473.540073][ T1106] ======================================================= [ 477.899160][ T1273] futex_wake_op: trinity-c0 tries to shift op by 1216; fix this program [ 481.172151][ T1305] futex_wake_op: trinity-c1 tries to shift op by 32; fix this program [ 482.235708][ T1351] futex_wake_op: trinity-c2 tries to shift op by -1131; fix this program [ 511.130182][ T1576] trinity-c2 (1576): attempted to duplicate a private mapping with mremap. This is not supported. [ 517.575042][ T1637] futex_wake_op: trinity-c0 tries to shift op by 290; fix this program [ 529.915814][ T1688] Invalid ELF header len 1 [ 553.563843][ T2070] mmap: trinity-c0 (2070): VmData 15699968 exceed data ulimit 1. Update limits or use boot option ignore_rlimit_data. [ 604.346182][ T2590] futex_wake_op: trinity-c3 tries to shift op by -1; fix this program [ 636.036421][ T2929] Unable to find swap-space signature [ 648.671070][ T3072] Unable to find swap-space signature [ 648.763689][ T3072] futex_wake_op: trinity-c0 tries to shift op by -1; fix this program [ 657.578846][ T3225] Unable to find swap-space signature [ 667.641713][ T3279] futex_wake_op: trinity-c1 tries to shift op by -2; fix this program [ 703.959704][ T3725] Unable to find swap-space signature [ 721.396457][ T467] hwclock: can't open '/dev/misc/rtc': No such file or directory [ 721.694925][ T3999] Unable to find swap-space signature [ 723.832302][ T4055] Unable to find swap-space signature [ 729.678335][ T436] sysrq: Emergency Sync [ 729.680680][ T61] Emergency Sync complete [ 729.682262][ T436] sysrq: Resetting Kboot worker: lkp-worker34 Elapsed time: 780 kvm=( qemu-system-x86_64 -enable-kvm -cpu SandyBridge -kernel $kernel -initrd initrd-vm-snb-157.cgz -m 16384 -smp 2 -device e1000,netdev=net0 -netdev user,id=net0,hostfwd=tcp::32032-:22 -boot order=nc -no-reboot -watchdog i6300esb -watchdog-action debug -rtc base=localtime -serial stdio -display none -monitor null ) append=( ip=::::vm-snb-157::dhcp root=/dev/ram0 RESULT_ROOT=/result/trinity/300s/vm-snb/yocto-x86_64-minimal-20190520.cgz/x86_64-randconfig-a002-20220131/gcc-9/b77e315a96445e5f19a83546c73d2abbcedfa5db/3 BOOT_IMAGE=/pkg/linux/x86_64-randconfig-a002-20220131/gcc-9/b77e315a96445e5f19a83546c73d2abbcedfa5db/vmlinuz-5.17.0-rc2-00169-gb77e315a9644 branch=axboe-block/for-next job=/job-script user=lkp ARCH=x86_64 kconfig=x86_64-randconfig-a002-20220131 commit=b77e315a96445e5f19a83546c73d2abbcedfa5db vmalloc=128M initramfs_async=0 page_owner=on max_uptime=2100 result_service=tmpfs selinux=0 debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 net.ifnames=0 printk.devkmsg=on panic=-1 softlockup_panic=1 nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0 drbd.minor_count=8 systemd.log_level=err ignore_loglevel console=tty0 earlyprintk=ttyS0,115200 console=ttyS0,115200 vga=normal rw rcuperf.shutdown=0 watchdog_thresh=240 ) "${kvm[@]}" -append "${append[*]}" To reproduce: # build kernel cd linux cp config-5.17.0-rc2-00169-gb77e315a9644 .config make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage modules make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 INSTALL_MOD_PATH=<mod-install-dir> modules_install cd <mod-install-dir> find lib/ | cpio -o -H newc --quiet | gzip > modules.cgz git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp qemu -k <bzImage> -m modules.cgz job-script # job-script is attached in this email # if come across any failure that blocks the test, # please remove ~/.lkp and /lkp dir to run from a clean state. --- 0DAY/LKP+ Test Infrastructure Open Source Technology Center https://lists.01.org/hyperkitty/list/lkp@lists.01.org Intel Corporation Thanks, Oliver Sang