From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH RT] tty: serial: st-asc: Make the locking RT aware
Date: Tue, 21 Mar 2017 19:51:47 +0100 (CET)
Message-ID: <alpine.DEB.2.20.1703211950040.3776@nanos>
References: <1490112340-29772-1-git-send-email-lionel.debieve@st.com> <20170321144437.569440c2@vmware.local.home>
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Cc: lionel.debieve@st.com, linux-rt-users@vger.kernel.org,
        linux-kernel@vger.kernel.org, bigeasy@linutronix.de,
        Patrice Chotard <patrice.chotard@st.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jslaby@suse.com>
To: Steven Rostedt <rostedt@goodmis.org>
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <20170321144437.569440c2@vmware.local.home>
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On Tue, 21 Mar 2017, Steven Rostedt wrote:
> >  	/*
> >  	 * Disable interrupts so we don't get the IRQ line bouncing
> 
> I'm nervous about the above comment, which in full is:
> 
> 	/*
> 	 * Disable interrupts so we don't get the IRQ line bouncing
> 	 * up and down while interrupts are disabled.
> 	 */
> 
> I'm not sure if disabling interrupts helps on an SMP system. This patch
> does change what happens when port->sysrq is set. But I'm not sure we
> care.

It disables interrupts at the device level which obviously helps whether on
SMP or not.

Thanks,

	tglx