Re: fsck segfaults on rpi3 running 13-stable

On Feb 12, 2023, at 11:13, bob prohaska <fbsd@www.zefox.net> wrote:

> On Sun, Feb 12, 2023 at 09:21:20AM -0800, Mark Millard wrote:
>> 
>> But the debugger inforation/symbols from your system are
>> needed to get symbolic results from that file. My instance
>> of main is not going to be a match.
>> 
>> You need to be the one getting the backtrace from your
>> system.
>> 
> 
> The -current system isn't updated yet, just running buildworld. 
> There's no problem regenerating the core dump.
> 
> I've gotten as far as
> 
> root@www:~ # lldb --core ./fsck_ffs.core
> (lldb) target create --core "./fsck_ffs.core"
> Core file '/root/fsck_ffs.core' (aarch64) was loaded.
> (lldb) 
> 
> Typing "gui" brings up a curses window, but I've no
> idea what to do next. 
> 
> Some guidance will be needed to make further progress.
> Is there a beginners's tutorial somewhere?

help in lldb reports:

. . .
  bt        -- Show the current thread's call stack.  Any numeric argument displays at most that many frames.  The argument 'all' displays all threads.  Use 'settings set frame-format' to customize
               the printing of individual frames and 'settings set thread-format' to customize the thread header.
. . .

So typing:

bt all

should attempt to produce a backtrace (of each thread).
(There is both exit and quit to leave lldb.)

I'll note that another option is to run fsck_ffs from
lldb in the first place. The below is running:
"fsck_ffs -n" (which is not really a valid command)

# which fsck_ffs
/sbin/fsck_ffs

# lldb /sbin/fsck_ffs
(lldb) target create "/sbin/fsck_ffs"
Current executable set to '/sbin/fsck_ffs' (aarch64).
(lldb) run -n
Process 8977 launched: '/sbin/fsck_ffs' (aarch64)
usage: fsck_ffs [-BCdEFfnpRrSyZ] [-b block] [-c level] [-m mode] filesystem ...
Process 8977 exited with status = 1 (0x00000001)
(lldb) 

So you would use something else than "-n".

Mine, of course, does not stop for the problem, but once
yours does, you could use the "bt all" command.


===
Mark Millard
marklmi at yahoo.com