FYI, we noticed the below changes on https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master commit 15c4f638f3d41bae52105ca4c0c8760afbcbeaab ("directio: add block polling support") +-------------------------------------------------+------------+------------+ | | a0fa9647a5 | 15c4f638f3 | +-------------------------------------------------+------------+------------+ | boot_successes | 16 | 17 | | boot_failures | 0 | 12 | | WARNING:at_kernel/sched/core.c:#__might_sleep() | 0 | 11 | | backtrace:vfs_read | 0 | 3 | | backtrace:SyS_read | 0 | 3 | | BUG:kernel_test_crashed | 0 | 1 | +-------------------------------------------------+------------+------------+ [ 32.952193] BTRFS: creating UUID tree [ 53.739325] random: nonblocking pool is initialized [ 151.793376] ------------[ cut here ]------------ [ 151.794683] WARNING: CPU: 3 PID: 8363 at kernel/sched/core.c:7533 __might_sleep+0x9f/0xb0() [ 151.796521] do not call blocking ops when !TASK_RUNNING; state=2 set at [] do_blockdev_direct_IO+0x126b/0x2c20 [ 151.798498] Modules linked in: btrfs xor raid6_pq dm_mod rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver sg sr_mod cdrom ata_generic pata_acpi ppdev snd_pcm snd_timer snd soundcore serio_raw pcspkr parport_pc parport floppy acpi_cpufreq ata_piix libata i2c_piix4 [ 151.804351] CPU: 3 PID: 8363 Comm: dd Not tainted 4.3.0-06686-g15c4f63 #1 [ 151.805524] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014 [ 151.806800] ------------[ cut here ]------------ [ 151.806820] WARNING: CPU: 0 PID: 8412 at kernel/sched/core.c:7533 __might_sleep+0x9f/0xb0() [ 151.806824] do not call blocking ops when !TASK_RUNNING; state=2 set at [] do_blockdev_direct_IO+0x126b/0x2c20 [ 151.806834] Modules linked in: btrfs xor raid6_pq dm_mod rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver sg sr_mod cdrom ata_generic pata_acpi ppdev snd_pcm snd_timer snd soundcore serio_raw pcspkr parport_pc parport floppy acpi_cpufreq ata_piix libata i2c_piix4 [ 151.815996] ffffffff81b9a8e8 ffff88003ef738d0 ffffffff81409c82 ffff88003ef73918 [ 151.817824] ffff88003ef73908 ffffffff81078f56 ffffffff81b91568 00000000000004a7 [ 151.819567] ------------[ cut here ]------------ [ 151.819573] WARNING: CPU: 2 PID: 8435 at kernel/sched/core.c:7533 __might_sleep+0x9f/0xb0() [ 151.819576] do not call blocking ops when !TASK_RUNNING; state=2 set at [] do_blockdev_direct_IO+0x126b/0x2c20 [ 151.819589] Modules linked in: btrfs xor raid6_pq dm_mod rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver sg sr_mod cdrom ata_generic pata_acpi ppdev snd_pcm snd_timer snd soundcore serio_raw pcspkr parport_pc parport floppy acpi_cpufreq ata_piix libata i2c_piix4 [ 151.828384] 0000000000000000 ffff88003ef73a48 ffff88007ddb0000 ffff88003ef73968 [ 151.830244] Call Trace: [ 151.830953] [] dump_stack+0x4b/0x69 [ 151.831946] [] warn_slowpath_common+0x86/0xc0 [ 151.832969] [] warn_slowpath_fmt+0x4c/0x50 [ 151.833976] [] ? do_blockdev_direct_IO+0x126b/0x2c20 [ 151.835088] [] ? do_blockdev_direct_IO+0x126b/0x2c20 [ 151.836195] [] __might_sleep+0x9f/0xb0 [ 151.837169] [] __do_page_fault+0x15a/0x410 [ 151.838166] [] trace_do_page_fault+0x43/0x110 [ 151.839214] [] do_async_page_fault+0x1a/0xa0 [ 151.840268] [] async_page_fault+0x28/0x30 [ 151.841260] [] ? do_blockdev_direct_IO+0x1297/0x2c20 [ 151.842420] [] ? btrfs_page_exists_in_range+0xe0/0xe0 [btrfs] [ 151.843956] [] ? finish_ordered_fn+0x20/0x20 [btrfs] [ 151.845034] [] __blockdev_direct_IO+0x43/0x50 [ 151.846082] [] ? finish_ordered_fn+0x20/0x20 [btrfs] [ 151.847191] [] btrfs_direct_IO+0x1aa/0x310 [btrfs] [ 151.848255] [] ? finish_ordered_fn+0x20/0x20 [btrfs] [ 151.849372] [] generic_file_read_iter+0x488/0x5b0 [ 151.850466] [] ? lru_cache_add_active_or_unevictable+0x27/0x90 [ 151.852036] [] __vfs_read+0xa7/0xd0 [ 151.852960] [] vfs_read+0x86/0x130 [ 151.853911] [] SyS_read+0x46/0xa0 [ 151.854872] [] entry_SYSCALL_64_fastpath+0x12/0x71 [ 151.855935] ---[ end trace cce58b9a28c7a964 ]--- [ 151.855938] CPU: 0 PID: 8412 Comm: dd Not tainted 4.3.0-06686-g15c4f63 #1 To reproduce: git clone git://git.kernel.org/pub/scm/linux/kernel/git/wfg/lkp-tests.git cd lkp-tests bin/lkp install job.yaml # job file is attached in this email bin/lkp run job.yaml Thanks, Ying Huang