linux-kernel - Re: [PATCH printk v3 13/19] printk: nbcon: Show replay message on takeover

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: <ZqpRO6YImKDRL8bS@pathway.suse.cz>
Date: Wed, 31 Jul 2024 16:59:07 +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,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: Re: [PATCH printk v3 13/19] printk: nbcon: Show replay message on
 takeover

On Mon 2024-07-22 19:25:33, John Ogness wrote:
> An emergency or panic context can takeover console ownership
> while the current owner was printing a printk message. The
> atomic printer will re-print the message that the previous
> owner was printing. However, this can look confusing to the
> user and may even seem as though a message was lost.
> 
>   [3430014.1
>   [3430014.181123] usb 1-2: Product: USB Audio
> 
> Add a new field @nbcon_prev_seq to struct console to track
> the sequence number to print that was assigned to the previous
> console owner. If this matches the sequence number to print
> that the current owner is assigned, then a takeover must have
> occurred. In this case, print an additional message to inform
> the user that the previous message is being printed again.
> 
>   [3430014.1
>   ** replaying previous printk message **
>   [3430014.181123] usb 1-2: Product: USB Audio
> 
> Signed-off-by: John Ogness <john.ogness@...utronix.de>

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

Best Regards,
Petr