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Date:   Tue, 11 Aug 2020 13:47:29 -0700
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Subject: Re: [PATCH v5 4/4] printk: use the lockless ringbuffer
From:   Nick Desaulniers <ndesaulniers@google.com>
To:     john.ogness@linutronix.de
Cc:     gregkh@linuxfoundation.org, kexec@lists.infradead.org,
        linux-kernel@vger.kernel.org, parri.andrea@gmail.com,
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From what I can tell, I think this patch ("printk: use the lockless
ringbuffer") breaks lx-dmesg in CONFIG_GDB_SCRIPTS.

(gdb) lx-dmesg
Python Exception <class 'gdb.error'> No symbol "log_first_idx" in specified context.: 
Error occurred in Python: No symbol "log_first_idx" in specified context.

This command is used to dump the printk log buffer.

It looks like the only places left in the kernel that reference are:

- Documentation/admin-guide/kdump/gdbmacros.txt
- Documentation/admin-guide/kdump/vmcoreinfo.rst
- scripts/gdb/linux/dmesg.py

I believe this commit removed log_first_idx, so all of the above probably need
to be fixed up, too.

~ Nick