Is it possible that the issue is not due to this change? This change is just to call different API to allocate memory, which is equivalent to kzalloc()+vzalloc(). Before the change: try kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL); ... and then below if the former is failed. vzalloc(sizeof(*vs)); After the change: try kmalloc_node(size, FP_KERNEL|GFP_ZERO|__GFP_NOWARN|__GFP_NORETRY, node); ... and then below if the former is failed __vmalloc_node(size, 1, GFP_KERNEL|GFP_ZERO, node, __builtin_return_address(0)); The below is the first WARNING in uploaded dmesg. I assume it was called before to open /dev/vhost-scsi. Will this test try to open /dev/vhost-scsi? [ 5.095515] ============================= [ 5.095515] WARNING: suspicious RCU usage [ 5.095515] 5.11.0-rc4-00008-g79991caf5202 #1 Not tainted [ 5.095534] ----------------------------- [ 5.096041] security/smack/smack_lsm.c:351 RCU-list traversed in non-reader section!! [ 5.096982] [ 5.096982] other info that might help us debug this: [ 5.096982] [ 5.097953] [ 5.097953] rcu_scheduler_active = 1, debug_locks = 1 [ 5.098739] no locks held by kthreadd/2. [ 5.099237] [ 5.099237] stack backtrace: [ 5.099537] CPU: 0 PID: 2 Comm: kthreadd Not tainted 5.11.0-rc4-00008-g79991caf5202 #1 [ 5.100470] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 5.101442] Call Trace: [ 5.101807] dump_stack+0x15f/0x1bf [ 5.102298] smack_cred_prepare+0x400/0x420 [ 5.102840] ? security_prepare_creds+0xd4/0x120 [ 5.103441] security_prepare_creds+0x84/0x120 [ 5.103515] prepare_creds+0x3f1/0x580 [ 5.103515] copy_creds+0x65/0x480 [ 5.103515] copy_process+0x7b4/0x3600 [ 5.103515] ? check_prev_add+0xa40/0xa40 [ 5.103515] ? lockdep_enabled+0xd/0x60 [ 5.103515] ? lock_is_held_type+0x1a/0x100 [ 5.103515] ? __cleanup_sighand+0xc0/0xc0 [ 5.103515] ? lockdep_unlock+0x39/0x160 [ 5.103515] kernel_clone+0x165/0xd20 [ 5.103515] ? copy_init_mm+0x20/0x20 [ 5.103515] ? pvclock_clocksource_read+0xd9/0x1a0 [ 5.103515] ? sched_clock_local+0x99/0xc0 [ 5.103515] ? kthread_insert_work_sanity_check+0xc0/0xc0 [ 5.103515] kernel_thread+0xba/0x100 [ 5.103515] ? __ia32_sys_clone3+0x40/0x40 [ 5.103515] ? kthread_insert_work_sanity_check+0xc0/0xc0 [ 5.103515] ? do_raw_spin_unlock+0xa9/0x160 [ 5.103515] kthreadd+0x68f/0x7a0 [ 5.103515] ? kthread_create_on_cpu+0x160/0x160 [ 5.103515] ? lockdep_hardirqs_on+0x77/0x100 [ 5.103515] ? _raw_spin_unlock_irq+0x24/0x60 [ 5.103515] ? kthread_create_on_cpu+0x160/0x160 [ 5.103515] ret_from_fork+0x22/0x30 Thank you very much! Dongli Zhang On 2/6/21 7:03 PM, kernel test robot wrote: > > Greeting, > > FYI, we noticed the following commit (built with gcc-9): > > commit: 79991caf5202c7989928be534727805f8f68bb8d ("vdpa_sim_net: Add support for user supported devices") > https://urldefense.com/v3/__https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git__;!!GqivPVa7Brio!LfgrgVVtPAjwjqTZX8yANgsix4f3cJmAA_CcMeCVymh5XYcamWdR9dnbIQA-p61PJtI$ Dongli-Zhang/vhost-scsi-alloc-vhost_scsi-with-kvzalloc-to-avoid-delay/20210129-191605 > > > in testcase: trinity > version: trinity-static-x86_64-x86_64-f93256fb_2019-08-28 > with following parameters: > > runtime: 300s > > test-description: Trinity is a linux system call fuzz tester. > test-url: https://urldefense.com/v3/__http://codemonkey.org.uk/projects/trinity/__;!!GqivPVa7Brio!LfgrgVVtPAjwjqTZX8yANgsix4f3cJmAA_CcMeCVymh5XYcamWdR9dnbIQA-6Y4x88c$ > > > on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G > > caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): > > > +-------------------------------------------------------------------------+------------+------------+ > | | 39502d042a | 79991caf52 | > +-------------------------------------------------------------------------+------------+------------+ > | boot_successes | 0 | 0 | > | boot_failures | 62 | 57 | > | WARNING:suspicious_RCU_usage | 62 | 57 | > | security/smack/smack_lsm.c:#RCU-list_traversed_in_non-reader_section | 62 | 57 | > | security/smack/smack_access.c:#RCU-list_traversed_in_non-reader_section | 62 | 57 | > | BUG:workqueue_lockup-pool | 33 | 40 | > | BUG:kernel_hang_in_boot_stage | 6 | 2 | > | net/mac80211/util.c:#RCU-list_traversed_in_non-reader_section | 23 | 15 | > | WARNING:SOFTIRQ-safe->SOFTIRQ-unsafe_lock_order_detected | 18 | | > | WARNING:inconsistent_lock_state | 5 | | > | inconsistent{SOFTIRQ-ON-W}->{IN-SOFTIRQ-W}usage | 5 | | > | calltrace:asm_call_irq_on_stack | 2 | | > | RIP:lock_acquire | 2 | | > | RIP:check_kcov_mode | 1 | | > | RIP:native_safe_halt | 2 | | > | INFO:rcu_sched_self-detected_stall_on_CPU | 2 | | > | RIP:clear_page_rep | 1 | | > | WARNING:at_drivers/gpu/drm/vkms/vkms_crtc.c:#vkms_vblank_simulate | 9 | 7 | > | RIP:vkms_vblank_simulate | 9 | 7 | > | RIP:__slab_alloc | 3 | 3 | > | RIP:__do_softirq | 2 | | > | RIP:console_unlock | 6 | 3 | > | invoked_oom-killer:gfp_mask=0x | 1 | | > | Mem-Info | 1 | | > | RIP:vprintk_emit | 1 | | > | RIP:__asan_load4 | 1 | | > | kernel_BUG_at_kernel/sched/core.c | 0 | 1 | > | invalid_opcode:#[##] | 0 | 1 | > | RIP:sched_cpu_dying | 0 | 1 | > | WARNING:possible_circular_locking_dependency_detected | 0 | 1 | > | Kernel_panic-not_syncing:Fatal_exception | 0 | 1 | > | net/ipv4/ipmr.c:#RCU-list_traversed_in_non-reader_section | 0 | 8 | > | RIP:arch_local_irq_restore | 0 | 1 | > | RIP:idr_get_free | 0 | 1 | > | net/ipv6/ip6mr.c:#RCU-list_traversed_in_non-reader_section | 0 | 2 | > +-------------------------------------------------------------------------+------------+------------+ > > > If you fix the issue, kindly add following tag > Reported-by: kernel test robot <oliver.sang@xxxxxxxxx> > > > [ 890.196279] ============================= > [ 890.212608] WARNING: suspicious RCU usage > [ 890.228281] 5.11.0-rc4-00008-g79991caf5202 #1 Tainted: G W > [ 890.244087] ----------------------------- > [ 890.259417] net/ipv4/ipmr.c:138 RCU-list traversed in non-reader section!! > [ 890.275043] > [ 890.275043] other info that might help us debug this: > [ 890.275043] > [ 890.318497] > [ 890.318497] rcu_scheduler_active = 2, debug_locks = 1 > [ 890.346089] 2 locks held by trinity-c1/2476: > [ 890.360897] #0: ffff888149d6f400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xc0/0xe0 > [ 890.375165] #1: ffff8881cabfd5c8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xa0/0x9c0 > [ 890.389706] > [ 890.389706] stack backtrace: > [ 890.416375] CPU: 1 PID: 2476 Comm: trinity-c1 Tainted: G W 5.11.0-rc4-00008-g79991caf5202 #1 > [ 890.430706] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 > [ 890.444971] Call Trace: > [ 890.458554] dump_stack+0x15f/0x1bf > [ 890.471996] ipmr_get_table+0x140/0x160 > [ 890.485328] ipmr_vif_seq_start+0x4d/0xe0 > [ 890.498620] seq_read_iter+0x1b2/0x9c0 > [ 890.511469] ? kvm_sched_clock_read+0x14/0x40 > [ 890.524008] ? sched_clock+0x1b/0x40 > [ 890.536095] ? iov_iter_init+0x7c/0xa0 > [ 890.548028] seq_read+0x2fd/0x3e0 > [ 890.559948] ? seq_hlist_next_percpu+0x140/0x140 > [ 890.572204] ? should_fail+0x78/0x2a0 > [ 890.584189] ? write_comp_data+0x2a/0xa0 > [ 890.596235] ? __sanitizer_cov_trace_pc+0x1d/0x60 > [ 890.608134] ? seq_hlist_next_percpu+0x140/0x140 > [ 890.620042] proc_reg_read+0x14e/0x180 > [ 890.631585] do_iter_read+0x397/0x420 > [ 890.642843] vfs_readv+0xf5/0x160 > [ 890.653833] ? vfs_iter_read+0x80/0x80 > [ 890.664229] ? __fdget_pos+0xc0/0xe0 > [ 890.674236] ? pvclock_clocksource_read+0xd9/0x1a0 > [ 890.684259] ? kvm_sched_clock_read+0x14/0x40 > [ 890.693852] ? sched_clock+0x1b/0x40 > [ 890.702898] ? sched_clock_cpu+0x18/0x120 > [ 890.711648] ? write_comp_data+0x2a/0xa0 > [ 890.720243] ? __sanitizer_cov_trace_pc+0x1d/0x60 > [ 890.729290] do_readv+0x111/0x260 > [ 890.738205] ? vfs_readv+0x160/0x160 > [ 890.747154] ? lockdep_hardirqs_on+0x77/0x100 > [ 890.756100] ? syscall_enter_from_user_mode+0x8a/0x100 > [ 890.765126] do_syscall_64+0x34/0x80 > [ 890.773795] entry_SYSCALL_64_after_hwframe+0x44/0xa9 > [ 890.782630] RIP: 0033:0x453b29 > [ 890.791189] Code: 00 f3 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 0f 83 3b 84 00 00 c3 66 2e 0f 1f 84 00 00 00 00 > [ 890.810866] RSP: 002b:00007ffcda44fb18 EFLAGS: 00000246 ORIG_RAX: 0000000000000013 > [ 890.820764] RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 0000000000453b29 > [ 890.830792] RDX: 000000000000009a RSI: 0000000001de1c00 RDI: 00000000000000b9 > [ 890.840626] RBP: 00007ffcda44fbc0 R08: 722c279d69ffc468 R09: 0000000000000400 > [ 890.850366] R10: 0098d82a42c63c22 R11: 0000000000000246 R12: 0000000000000002 > [ 890.860001] R13: 00007f042ae6f058 R14: 00000000010a2830 R15: 00007f042ae6f000 > > > > To reproduce: > > # build kernel > cd linux > cp config-5.11.0-rc4-00008-g79991caf5202 .config > make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage > > git clone https://urldefense.com/v3/__https://github.com/intel/lkp-tests.git__;!!GqivPVa7Brio!LfgrgVVtPAjwjqTZX8yANgsix4f3cJmAA_CcMeCVymh5XYcamWdR9dnbIQA-Qkr9TyI$ > cd lkp-tests > bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email > > > > Thanks, > Oliver Sang >