linux-kernel - Re: [RFC][PATCH] printk: Fixup the nmi printk mess

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: <20150610115411.2b9184aa@gandalf.local.home>
Date:	Wed, 10 Jun 2015 11:54:11 -0400
From:	Steven Rostedt <rostedt@...dmis.org>
To:	Peter Zijlstra <peterz@...radead.org>
Cc:	Petr Mladek <pmladek@...e.cz>, linux-kernel@...r.kernel.org,
	jkosina@...e.cz, paulmck@...ux.vnet.ibm.com,
	Ingo Molnar <mingo@...nel.org>,
	Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [RFC][PATCH] printk: Fixup the nmi printk mess

On Wed, 10 Jun 2015 17:32:53 +0200
Peter Zijlstra <peterz@...radead.org> wrote:

> > Note that the backtraces used to be serialized via
> > static arch_spinlock_t lock = __ARCH_SPIN_LOCK_UNLOCKED
> > in the past. See the commit
> > a9edc8809328 ("x86/nmi: Perform a safe NMI stack trace on all CPUs")
> 
> We could easily add a static raw_spinlock_t to __printk_nmi_flush() and
> serialize its invocations if people think that is important.

Yes please. One thing about the original change is that it made the NMI
backtraces readable. I hated the interleaving of the backtraces, as it
made it almost impossible to to debug.

-- Steve
--
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/