2002-10-10 17:03:38

by Sylvain Pasche

[permalink] [raw]
Subject: 2.5.41 Autofs4: bad: scheduling while atomic!

bad: scheduling while atomic!
Call Trace:
[<c01161b1>] schedule+0x3d/0x4d4
[<c01123fd>] smp_apic_timer_interrupt+0x111/0x124
[<c0107595>] need_resched+0x1f/0x2a
[<c01a0068>] sysvipc_sem_read_proc+0x1b0/0x227
[<c01acba5>] serial_in+0x45/0x4c
[<c01aeadd>] serial8250_console_write+0x5d/0x1cc
[<c011ba26>] __call_console_drivers+0x3e/0x50
[<c011ba8b>] _call_console_drivers+0x53/0x58
[<c011bb45>] call_console_drivers+0xb5/0xe0
[<c011bed7>] release_console_sem+0xc3/0x164
[<c011bd7f>] printk+0x1a7/0x1f4
[<c011890f>] __might_sleep+0x4f/0x58
[<c013b57e>] kmalloc+0x5a/0x324
[<c014de8b>] wake_up_buffer+0xb/0x28
[<f887ebeb>] autofs4_wait+0x8f/0x330 [autofs4]
[<f887d723>] try_to_fill_dentry+0x3b/0x178 [autofs4]
[<f887d9b2>] autofs4_root_revalidate+0x152/0x1a4 [autofs4]
[<f887db85>] autofs4_root_lookup+0xe9/0x1e0 [autofs4]
[<c0158e08>] real_lookup+0x60/0xe8
[<c0159240>] do_lookup+0xe8/0x2d0
[<c0159a8e>] link_path_walk+0x666/0xa8c
[<c015a31b>] path_lookup+0x207/0x20c
[<c015a454>] __user_walk+0x28/0x40
[<c015543a>] vfs_lstat+0x16/0x44
[<c01559a7>] sys_lstat64+0x13/0x30
[<c01337e4>] sys_brk+0xc4/0xf0
[<c0108015>] error_code+0x2d/0x38
[<c01075d3>] syscall_call+0x7/0xb


Really not sure about it, but there is a lock_kernel() call in
the autofs4_root_lookup(). Maybe that's what is creating the atomic
context ?


2002-10-12 00:09:43

by Jeremy Fitzhardinge

[permalink] [raw]
Subject: Re: 2.5.41 Autofs4: bad: scheduling while atomic!

On Fri, 2002-10-11 at 11:23, Sylvain Pasche wrote:
Unfortunately, I did not keep the .config.

From what I remember, I had CONFIG_PREEMPT set and CONFIG_SMP not set.

I'm not under 2.5 now, but I can recompile and test again if you want
to be able to reproduce it and have more details..

I really can't see how it could get into a non-preemptable state along
that path. Did anything else bad happen in that session? Any oopses or
other funnies? Can you give more detail about what you were doing at
the time? Was it the first use of autofs, or had you been using it
heavily? How many autofs filesystems mounted?

Thanks,
J