Re: 2.6.21-rc7-mm2 hangs in boot (netconsole)

[Randy Dunlap <randy.dunlap@oracle.com>]

Andrew Morton wrote:
> On Mon, 30 Apr 2007 16:51:01 -0700
> Randy Dunlap <randy.dunlap@oracle.com> wrote:
> 
>> On Mon, 30 Apr 2007 08:16:53 -0700 Randy Dunlap wrote:
>>
>>> On Sun, 29 Apr 2007 22:23:54 -0700 Andrew Morton wrote:
>>>
>>>> On Sun, 29 Apr 2007 22:01:32 -0700 Randy Dunlap <randy.dunlap@oracle.com> wrote:
>>>>
>>>>> On Wed, 25 Apr 2007 22:57:16 -0700 Andrew Morton wrote:
>>>>>
>>>>>> ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.21-rc7/2.6.21-rc7-mm2/
>>>>> I'm getting a hang near the end of booting on x86_64 UP.
>>>>> The last initcall_debug function varies.  E.g.:
>>>>>
>>>>> 1/
>>>>> [    0.140257] Calling initcall 0xffffffff806f2fa8: init_misc_binfmt+0x0/0x3f()
>>>>> [    0.140266] initcall 0xffffffff806f2fa8: init_misc_binfmt+0x0/0x3f() returned 0.
>>>>> [    0.140275] initcall 0xffffffff806f2fa8 ran for 0 msecs: init_misc_binfmt+0x0/0x3f()
>>>>> [    0.140284] Calling initcall 0xffffffff806f2fe7: init_script_binfmt+0x0/0x12()
>>>>> [    0.140293] initcall 0xffffffff806f2fe7: init_script_binfmt+0x0/0x12() returned 0.
>>>>> [    0.140302] initcall 0xffffffff806f2fe7 ran for 0 msecs: init_script_binfmt+0x0/0x12()
>>>>> [    0.140310] Calling initcall 0xffffffff806f2ff9: init_elf_binfmt+0x0/0x12()
>>>>> [    0.140317] initcall 0xffffffff806f2ff9: init_elf_binfmt+0x0/0x12() returned 0.
>>>>> [    0.140326] initcall 0xffffffff806f2ff9 ran for 0 msecs: init_elf_binfmt+0x0/0x12()
>>>>> [    0.140335] Calling initcall 0xffffffff806f3de9: debugfs_init+0x0/0x4a()
>>>>> [    0.140344] initcall 0xffffffff806f3de9: debugfs_init+0x0/0x4a() returned 0.
>>>>> [    0.140351] initcall 0xffffffff806f3de9 ran for 0 msecs: debugfs_init+0x0/0x4a()
>>>>>
>>>>> 2/
>>>>> [    0.140206] Calling initcall 0xffffffff806efeb1: ksysfs_init+0x0/0x29()
>>>>> [    0.140215] initcall 0xffffffff806efeb1: ksysfs_init+0x0/0x29() returned 0.
>>>>> [    0.140222] initcall 0xffffffff806efeb1 ran for 0 msecs: ksysfs_init+0x0/0x29()
>>>>> [    0.140230] Calling initcall 0xffffffff806f25be: filelock_init+0x0/0x31()
>>>>> [    0.140242] initcall 0xffffffff806f25be: filelock_init+0x0/0x31() returned 0.
>>>>> [    0.140249] initcall 0xffffffff806f25be ran for 0 msecs: filelock_init+0x0/0x31()
>>>>> [    0.140258] Calling initcall 0xffffffff806f2fa8: init_misc_binfmt+0x0/0x3f()
>>>>> [    0.140266] initcall 0xffffffff806f2fa8: init_misc_binfmt+0x0/0x3f() returned 0.
>>>>> [    0.140276] initcall 0xffffffff806f2fa8 ran for 0 msecs: init_misc_binfmt+0x0/0x3f()
>>>>> [    0.140284] Calling initcall 0xffffffff806f2fe7: init_script_binfmt+0x0/0x12()
>>>>> [    0.140293] initcall 0xffffffff806f2fe7: init_script_binfmt+0x0/0x12() returned 0.
>>>>>
>>>> So perhaps it locks during a timer interrupt.
>>>>
>>>>> .config is attached.
>>>>>
>>>>> Any ideas/suggestions?
>>>> Just the usual: nothing from sysrq or NMI watchdog?
>>> Nothing from either of those.  I'll jiggle some config options.
>> config option changes didn't help, but removing
>> 	netconsole=<params>
>> from the kernel command line makes it all happy.  :(
> 
> argh.
> 
>> Do we know of netconsole hang problems?  (anyone?)
> 
> You have "time" as well?  I found on i386 uniproc that time+netconsole
> caused hangs because the printk timestamping code was taking
> xtime_lock for reading inside a write_seqlock.  But I though that Andi
> fixed that.  Perhaps i386 got fixed but x86_64 did not.

Yes, I have CONFIG_PRINTK_TIME=y and disabling it allows it to boot.  Thanks.

Maybe the patch isn't merged yet?

Now if I can just remember this until the next time that I hit it...

-- 
~Randy
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