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

Andrew Morton
2007-05-01T00:12:40Z

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.