linux-kernel - Re: [PATCH v5 4/4] printk: use the lockless ringbuffer

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200811204729.1116341-1-ndesaulniers@google.com>
Date:   Tue, 11 Aug 2020 13:47:29 -0700
From:   Nick Desaulniers <ndesaulniers@...gle.com>
To:     john.ogness@...utronix.de
Cc:     gregkh@...uxfoundation.org, kexec@...ts.infradead.org,
        linux-kernel@...r.kernel.org, parri.andrea@...il.com,
        paulmck@...nel.org, peterz@...radead.org, pmladek@...e.com,
        rostedt@...dmis.org, sergey.senozhatsky.work@...il.com,
        sergey.senozhatsky@...il.com, tglx@...utronix.de,
        torvalds@...ux-foundation.org, swboyd@...omium.org
Subject: Re: [PATCH v5 4/4] printk: use the lockless ringbuffer

>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