linux-kernel - Re: [PATCH][RT] ring-buffer: Convert reader_lock from raw_spin_lock into spin

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] [day] [month] [year] [list]

Message-ID: <alpine.LFD.2.02.1109272020060.2711@ionos>
Date:	Tue, 27 Sep 2011 20:21:10 +0200 (CEST)
From:	Thomas Gleixner <tglx@...utronix.de>
To:	Steven Rostedt <rostedt@...dmis.org>
cc:	LKML <linux-kernel@...r.kernel.org>,
	Peter Zijlstra <peterz@...radead.org>,
	Clark Williams <clark@...hat.com>
Subject: Re: [PATCH][RT] ring-buffer: Convert reader_lock from raw_spin_lock
 into spin_lock

On Tue, 27 Sep 2011, Steven Rostedt wrote:
> +	/*
> +	 * If an NMI die dumps out the content of the ring buffer
> +	 * do not grab locks. We also permanently disable the ring
> +	 * buffer too. A one time deal is all you get from reading
> +	 * the ring buffer from an NMI.
> +	 */
> +	if (!ok_to_lock()) {
> +		if (spin_trylock_irqsave(&cpu_buffer->reader_lock, *flags))
> +			return 1;
> +		printk("Dumping ring buffer from unsafe context\n");
> +		printk("Disabling new ring buffer writes\n");

And what exaclty is the point of these printks/ Aside of that they are
missing KERN_WTF before the string.

Thanks,

	tglx
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/