linux-kernel - Re: Why the mce reverts in 4.16-rt?

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: <20180711085101.553face7@gandalf.local.home>
Date:   Wed, 11 Jul 2018 08:51:01 -0400
From:   Steven Rostedt <rostedt@...dmis.org>
To:     Sebastian Andrzej Siewior <bigeasy@...utronix.de>
Cc:     Thomas Gleixner <tglx@...utronix.de>,
        linux-rt-users <linux-rt-users@...r.kernel.org>,
        LKML <linux-kernel@...r.kernel.org>
Subject: Re: Why the mce reverts in 4.16-rt?

On Wed, 11 Jul 2018 09:23:11 +0200
Sebastian Andrzej Siewior <bigeasy@...utronix.de> wrote:

> On 2018-07-10 20:56:24 [-0400], Steven Rostedt wrote:
> > Hi Sebastian,  
> Hi Steven,
> 
> > I'm looking at backporting patches from 4.16-rt and noticed that you
> > have:
> > 
> > Revert "x86: Convert mce timer to hrtimer"
> > Revert "x86/mce: use swait queue for mce wakeups"
> > 
> > With no explanation to why they were reverted. When did things change?
> > Should this be 4.14-rt material?  
> 
> from the announce email:
> |    Changes since v4.16.8-rt2:
> |    
> |      - Drop two MCE related patches. They are no longer required since the
> |        timer wheel rework.

Thanks, still would have preferred a comment in the revert commit
message ;-)

> 
> The timer wheel rework made it possible to have a raw_spin_lock_t in the
> timer_list timer. The problem with MCE was that it enqueued a timer from
> hardirq context which is now possible. So the patches are no longer
> required. This revert does not fix a bug in v4.14 nor does it break
> anything.

OK, even though this doesn't fix anything, I think I'll still
backport it.

-- Steve