linux-kernel - Re: [PATCH printk] printk: flush consoles before checking progress

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: <ZRbUaldrGz8u6CNp@alley>
Date:   Fri, 29 Sep 2023 15:43:06 +0200
From:   Petr Mladek <pmladek@...e.com>
To:     John Ogness <john.ogness@...utronix.de>
Cc:     Sergey Senozhatsky <senozhatsky@...omium.org>,
        Steven Rostedt <rostedt@...dmis.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        linux-kernel@...r.kernel.org, Todd Brandt <todd.e.brandt@...el.com>
Subject: Re: [PATCH printk] printk: flush consoles before checking progress

On Fri 2023-09-29 13:38:33, John Ogness wrote:
> Commit 9e70a5e109a4 ("printk: Add per-console suspended state")
> removed console lock usage during resume and replaced it with
> the clearly defined console_list_lock and srcu mechanisms.
> 
> However, the console lock usage had an important side-effect
> of flushing the consoles. After its removal, consoles were no
> longer flushed before checking their progress.
> 
> Add the console_lock/console_unlock dance to the beginning
> of __pr_flush() to actually flush the consoles before checking
> their progress. Also add comments to clarify this additional
> usage of the console lock.
> 
> Finally, in case pr_flush() needs to poll-wait (for example,
> because there has been a handover to another CPU), reduce the
> polling interval from 100ms to 1ms. In the bug report it was
> mentioned that 100ms is unnecessarily long.
> 
> Reported-by: Todd Brandt <todd.e.brandt@...el.com>
> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217955
> Fixes: 9e70a5e109a4 ("printk: Add per-console suspended state")
> Signed-off-by: John Ogness <john.ogness@...utronix.de>

Looks good to me:

Reviewed-by: Petr Mladek <pmladek@...e.com>

I am going to wait a bit for eventual feedback and push it to
linux-next the following week.

Best Regards,
Petr