[BUG] Splat in __register_sysctl_table() in next-20220210

[BUG] Splat in __register_sysctl_table() in next-20220210

[Paul E. McKenney]

Hello!

I just wanted to be the 20th person to report the below splat in
init_fs_stat_sysctls() during boot.  ;-)

It happens on all rcutorture scenarios, for whatever that might be
worth.

						Thanx, Paul

------------------------------------------------------------------------

[    1.219815] calling  init_fs_stat_sysctls+0x0/0x37 @ 1
[    1.220440] CPU: 0 PID: 1 Comm: swapper Not tainted 5.17.0-rc3-next-20220210 #852
[    1.221353] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014
[    1.224133] Call Trace:
[    1.224439]  <TASK>
[    1.224702]  dump_stack_lvl+0x22/0x29
[    1.225122]  dump_stack+0x15/0x2a
[    1.225611]  __register_sysctl_table+0x4b2/0xab0
[    1.226158]  ? init_fs_open_sysctls+0x2b/0x2b
[    1.226755]  register_sysctl_mount_point+0x24/0x40
[    1.227396]  init_fs_stat_sysctls+0x2f/0x37
[    1.227884]  do_one_initcall+0x128/0x3e0
[    1.228445]  do_initcall_level+0xca/0x168
[    1.229215]  do_initcalls+0x66/0x95
[    1.229620]  do_basic_setup+0x18/0x1e
[    1.230105]  kernel_init_freeable+0xa9/0x113
[    1.230617]  ? rest_init+0x150/0x150
[    1.231101]  kernel_init+0x1c/0x200
[    1.231550]  ? rest_init+0x150/0x150
[    1.231981]  ret_from_fork+0x22/0x30
[    1.232471]  </TASK>
[    1.232743] initcall init_fs_stat_sysctls+0x0/0x37 returned 0 after 12029 usecs

Re: [BUG] Splat in __register_sysctl_table() in next-20220210

[Luis Chamberlain]

On Fri, Feb 11, 2022 at 09:04:55AM -0800, Paul E. McKenney wrote:
> Hello!
> 
> I just wanted to be the 20th person to report the below splat in
> init_fs_stat_sysctls() during boot.  ;-)
> 
> It happens on all rcutorture scenarios, for whatever that might be
> worth.

It should be fixed on today's linux-next, see this discussion:

https://lore.kernel.org/linux-ext4/20220210091648.w5wie3llqri5kfw3@quack3.lan/T/#mfc3683a68aaec8595cd5f26e138453132a3e1d43

Essentially there was a fix which Andrew merged. The Linus merged it.
But linux-next carried Andrew's fix too, so there was a double
registration.

Please let me know if you still see the issue on next-20220211 !

  Luis

Re: [BUG] Splat in __register_sysctl_table() in next-20220210

[Paul E. McKenney]

On Fri, Feb 11, 2022 at 10:02:49AM -0800, Luis Chamberlain wrote:
> On Fri, Feb 11, 2022 at 09:04:55AM -0800, Paul E. McKenney wrote:
> > Hello!
> > 
> > I just wanted to be the 20th person to report the below splat in
> > init_fs_stat_sysctls() during boot.  ;-)
> > 
> > It happens on all rcutorture scenarios, for whatever that might be
> > worth.
> 
> It should be fixed on today's linux-next, see this discussion:
> 
> https://lore.kernel.org/linux-ext4/20220210091648.w5wie3llqri5kfw3@quack3.lan/T/#mfc3683a68aaec8595cd5f26e138453132a3e1d43
> 
> Essentially there was a fix which Andrew merged. The Linus merged it.
> But linux-next carried Andrew's fix too, so there was a double
> registration.
> 
> Please let me know if you still see the issue on next-20220211 !

And next-20220211 worked just fine, thank you!

							Thanx, Paul