On Tue, Aug 5, 2014 at 5:06 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > On Tue, Aug 05, 2014 at 12:33:16PM +0400, Ilya Dryomov wrote: >> On Mon, Aug 4, 2014 at 2:30 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: >> > Hi, >> > >> > Ilya recently tripped over a nested sleep which made Ingo suggest we should >> > have debug checks for that. So I did some, see patch 7. Of course that >> > triggered a whole bunch of fail the instant I tried to boot my machine. >> > >> > With this series I can boot my test box and build a kernel on it, I'm fairly >> > sure that's far too limited a test to have found all, but its a start. >> >> FWIW, I'm getting a lot of these during light rbd testing. CC'ed >> netdev and linux-mm. > > Both are cond_resched() calls, and that's not blocking as such, just a > preemption point, so lets exclude those. OK, this one is a bit different. WARNING: CPU: 1 PID: 1744 at kernel/sched/core.c:7104 __might_sleep+0x58/0x90() do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff81070e10>] prepare_to_wait+0x50 /0xa0 Modules linked in: CPU: 1 PID: 1744 Comm: lt-ceph_test_li Not tainted 3.16.0-vm+ #113 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 0000000000001bc0 ffff88006c4479d8 ffffffff8156f455 0000000000000000 ffff88006c447a28 ffff88006c447a18 ffffffff81033357 0000000000000001 0000000000000000 0000000000000950 ffffffff817ee48a ffff88006dba6120 Call Trace: [<ffffffff8156f455>] dump_stack+0x4f/0x7c [<ffffffff81033357>] warn_slowpath_common+0x87/0xb0 [<ffffffff81033421>] warn_slowpath_fmt+0x41/0x50 [<ffffffff81078bb2>] ? trace_hardirqs_on_caller+0x182/0x1f0 [<ffffffff81070e10>] ? prepare_to_wait+0x50/0xa0 [<ffffffff81070e10>] ? prepare_to_wait+0x50/0xa0 [<ffffffff8105bc38>] __might_sleep+0x58/0x90 [<ffffffff8148c671>] lock_sock_nested+0x31/0xb0 [<ffffffff8148dfeb>] ? release_sock+0x1bb/0x200 [<ffffffff81498aaa>] sk_stream_wait_memory+0x18a/0x2d0 [<ffffffff810709a0>] ? woken_wake_function+0x10/0x10 [<ffffffff814e058f>] tcp_sendmsg+0xb6f/0xd70 [<ffffffff81509e9f>] inet_sendmsg+0xdf/0x100 [<ffffffff81509dc0>] ? inet_recvmsg+0x100/0x100 [<ffffffff81489f07>] sock_sendmsg+0x67/0x90 [<ffffffff810fe391>] ? might_fault+0x51/0xb0 [<ffffffff8148a252>] ___sys_sendmsg+0x2d2/0x2e0 [<ffffffff811428a0>] ? do_dup2+0xd0/0xd0 [<ffffffff811428a0>] ? do_dup2+0xd0/0xd0 [<ffffffff8105bfe0>] ? finish_task_switch+0x50/0x100 [<ffffffff811429d5>] ? __fget_light+0x45/0x60 [<ffffffff811429fe>] ? __fdget+0xe/0x10 [<ffffffff8148ad14>] __sys_sendmsg+0x44/0x70 [<ffffffff8148ad49>] SyS_sendmsg+0x9/0x10 [<ffffffff815764d2>] system_call_fastpath+0x16/0x1b Thanks, Ilya -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>