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From: sboyd@codeaurora.org (Stephen Boyd)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] tty: serial: msm: Fix lock init issue with earlycon
Date: Mon, 20 Oct 2014 15:20:03 -0700	[thread overview]
Message-ID: <20141020222003.GD12469@codeaurora.org> (raw)
In-Reply-To: <20141020221656.GC12469@codeaurora.org>

On 10/20, Stephen Boyd wrote:
> On 10/20, Peter Hurley wrote:
> > 
> > FWIW, __msm_console_write() is a deadlock-waiting-to_happen since it does
> > not disable interrupts with spin_lock_irqsave().
> > 
> 
> Yeah we should fix that. As far as I can tell we've never used
> the irqsave variant of the lock in the console path. Did this
> become necessary at some point since this driver was introduced?
> I'm wondering how many stable trees need the fix.

Actually I don't see this case. It looks like the console is
always called in call_console_drivers() with irqs saved and
disabled via the logbuf_lock in console_cont_flush() or
console_unlock().

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

  reply	other threads:[~2014-10-20 22:20 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-17 13:13 [PATCH] tty: serial: msm: Fix lock init issue with earlycon Kumar Gala
2014-10-20 18:27 ` Stephen Boyd
2014-10-20 21:38   ` Peter Hurley
2014-10-20 22:16     ` Stephen Boyd
2014-10-20 22:20       ` Stephen Boyd [this message]
2014-10-21 19:42         ` Peter Hurley

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