random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) ============================= WARNING: suspicious RCU usage 4.17.0-rc1+ #12 Not tainted ----------------------------- include/linux/rcupdate.h:304 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 6 locks held by kworker/u4:1/22: #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: __write_once_size include/linux/compiler.h:215 [inline] #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:57 [inline] #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: process_one_work+0xaef/0x1b50 kernel/workqueue.c:2116 #1: (ptrval) ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0xb46/0x1b50 kernel/workqueue.c:2120 #2: (ptrval) (&type->s_umount_key#29){++++}, at: trylock_super+0x22/0x110 fs/super.c:399 #3: (ptrval) (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0x9a/0x1a0 mm/page-writeback.c:2341 #4: (ptrval) (jbd2_handle){.+.+}, at: start_this_handle+0x581/0x1250 fs/jbd2/transaction.c:385 #5: (ptrval) (rcu_read_lock){....}, at: find_get_pages_range_tag+0x139/0x1250 mm/filemap.c:1874 stack backtrace: CPU: 0 PID: 22 Comm: kworker/u4:1 Not tainted 4.17.0-rc1+ #12 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 lockdep_rcu_suspicious+0x14a/0x153 kernel/locking/lockdep.c:4592 rcu_preempt_sleep_check include/linux/rcupdate.h:303 [inline] ___might_sleep+0x26d/0x320 kernel/sched/core.c:6153 __might_sleep+0x95/0x190 kernel/sched/core.c:6141 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3378 [inline] __do_kmalloc mm/slab.c:3716 [inline] __kmalloc+0x2b9/0x760 mm/slab.c:3727 kmalloc_array include/linux/slab.h:631 [inline] kcalloc include/linux/slab.h:642 [inline] numa_crng_init drivers/char/random.c:798 [inline] crng_reseed+0x427/0x920 drivers/char/random.c:923 credit_entropy_bits+0x98d/0xa30 drivers/char/random.c:708 add_interrupt_randomness+0x494/0x860 drivers/char/random.c:1254 handle_irq_event_percpu+0xf9/0x1c0 kernel/irq/handle.c:191 handle_irq_event+0xa7/0x135 kernel/irq/handle.c:206 handle_edge_irq+0x20f/0x870 kernel/irq/chip.c:791 generic_handle_irq_desc include/linux/irqdesc.h:159 [inline] handle_irq+0x18c/0x2e7 arch/x86/kernel/irq_64.c:77 do_IRQ+0x78/0x190 arch/x86/kernel/irq.c:245 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:642 RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x1/0x20 kernel/kcov.c:194 RSP: 0018:ffff8801d941dbf0 EFLAGS: 00000202 ORIG_RAX: ffffffffffffffda RAX: ffff8801d94125c0 RBX: 000000007fffffff RCX: ffffffff8194e3dc RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff8801d941dfb8 R08: ffff8801d94125c0 R09: fffff94000de7f23 R10: fffff94000de7f23 R11: ffffea0006f3f91f R12: 0000000000000010 R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8801d941df90 pagevec_lookup_range_tag+0x40/0x80 mm/swap.c:1006 mpage_prepare_extent_to_map+0x3ff/0x1100 fs/ext4/inode.c:2633 ext4_writepages+0x186f/0x4030 fs/ext4/inode.c:2853 do_writepages+0x9a/0x1a0 mm/page-writeback.c:2341 __writeback_single_inode+0x1e4/0x15c0 fs/fs-writeback.c:1323 writeback_sb_inodes+0x6f0/0x11a0 fs/fs-writeback.c:1587 __writeback_inodes_wb+0x1b0/0x320 fs/fs-writeback.c:1656 wb_writeback+0x9e4/0xf50 fs/fs-writeback.c:1765 wb_check_old_data_flush fs/fs-writeback.c:1867 [inline] wb_do_writeback fs/fs-writeback.c:1920 [inline] wb_workfn+0xfba/0x1770 fs/fs-writeback.c:1949 process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145 worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279 kthread+0x345/0x410 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 BUG: sleeping function called from invalid context at mm/slab.h:421 in_atomic(): 1, irqs_disabled(): 1, pid: 22, name: kworker/u4:1 6 locks held by kworker/u4:1/22: #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: __write_once_size include/linux/compiler.h:215 [inline] #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:57 [inline] #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: (ptrval) ((wq_completion)"writeback"){+.+.}, at: process_one_work+0xaef/0x1b50 kernel/workqueue.c:2116 #1: (ptrval) ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0xb46/0x1b50 kernel/workqueue.c:2120 #2: (ptrval) (&type->s_umount_key#29){++++}, at: trylock_super+0x22/0x110 fs/super.c:399 #3: (ptrval) (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0x9a/0x1a0 mm/page-writeback.c:2341 #4: (ptrval) (jbd2_handle){.+.+}, at: start_this_handle+0x581/0x1250 fs/jbd2/transaction.c:385 #5: (ptrval) (rcu_read_lock){....}, at: find_get_pages_range_tag+0x139/0x1250 mm/filemap.c:1874 irq event stamp: 59140 hardirqs last enabled at (59139): [] free_unref_page_list+0xc9a/0x12c0 mm/page_alloc.c:2849 hardirqs last disabled at (59140): [] interrupt_entry+0xb5/0xf0 arch/x86/entry/entry_64.S:625 softirqs last enabled at (59128): [] __do_softirq+0x778/0xaf5 kernel/softirq.c:311 softirqs last disabled at (59121): [] invoke_softirq kernel/softirq.c:365 [inline] softirqs last disabled at (59121): [] irq_exit+0x1d1/0x200 kernel/softirq.c:405 CPU: 0 PID: 22 Comm: kworker/u4:1 Not tainted 4.17.0-rc1+ #12 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 ___might_sleep.cold.87+0x11f/0x13a kernel/sched/core.c:6188 __might_sleep+0x95/0x190 kernel/sched/core.c:6141 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3378 [inline] __do_kmalloc mm/slab.c:3716 [inline] __kmalloc+0x2b9/0x760 mm/slab.c:3727 kmalloc_array include/linux/slab.h:631 [inline] kcalloc include/linux/slab.h:642 [inline] numa_crng_init drivers/char/random.c:798 [inline] crng_reseed+0x427/0x920 drivers/char/random.c:923 credit_entropy_bits+0x98d/0xa30 drivers/char/random.c:708 add_interrupt_randomness+0x494/0x860 drivers/char/random.c:1254 handle_irq_event_percpu+0xf9/0x1c0 kernel/irq/handle.c:191 handle_irq_event+0xa7/0x135 kernel/irq/handle.c:206 handle_edge_irq+0x20f/0x870 kernel/irq/chip.c:791 generic_handle_irq_desc include/linux/irqdesc.h:159 [inline] handle_irq+0x18c/0x2e7 arch/x86/kernel/irq_64.c:77 do_IRQ+0x78/0x190 arch/x86/kernel/irq.c:245 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:642 RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x1/0x20 kernel/kcov.c:194 RSP: 0018:ffff8801d941dbf0 EFLAGS: 00000202 ORIG_RAX: ffffffffffffffda RAX: ffff8801d94125c0 RBX: 000000007fffffff RCX: ffffffff8194e3dc RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff8801d941dfb8 R08: ffff8801d94125c0 R09: fffff94000de7f23 R10: fffff94000de7f23 R11: ffffea0006f3f91f R12: 0000000000000010 R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8801d941df90 pagevec_lookup_range_tag+0x40/0x80 mm/swap.c:1006 mpage_prepare_extent_to_map+0x3ff/0x1100 fs/ext4/inode.c:2633 ext4_writepages+0x186f/0x4030 fs/ext4/inode.c:2853 do_writepages+0x9a/0x1a0 mm/page-writeback.c:2341 __writeback_single_inode+0x1e4/0x15c0 fs/fs-writeback.c:1323 writeback_sb_inodes+0x6f0/0x11a0 fs/fs-writeback.c:1587 __writeback_inodes_wb+0x1b0/0x320 fs/fs-writeback.c:1656 wb_writeback+0x9e4/0xf50 fs/fs-writeback.c:1765 wb_check_old_data_flush fs/fs-writeback.c:1867 [inline] wb_do_writeback fs/fs-writeback.c:1920 [inline] wb_workfn+0xfba/0x1770 fs/fs-writeback.c:1949 process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145 worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279 kthread+0x345/0x410 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 random: crng init done can: request_module (can-proto-0) failed. can: request_module (can-proto-0) failed.