mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Ingo Molnar <mingo@kernel.org>
To: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chuck Ebbert <cebbert.lkml@gmail.com>,
	linux-kernel@vger.kernel.org,
	Andrew Morton <akpm@linux-foundation.org>,
	Tejun Heo <tj@kernel.org>, Andy Lutomirski <luto@amacapital.net>,
	Rusty Russell <rusty@rustcorp.com.au>,
	Peter Zijlstra <peterz@infradead.org>,
	Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
	Jiri Kosina <jkosina@suse.cz>,
	"H. Peter Anvin" <hpa@linux.intel.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Jason Baron <jbaron@akamai.com>,
	yrl.pp-manager.tt@hitachi.com, Borislav Petkov <bpetkov@suse.de>,
	Daniel Vetter <daniel.vetter@ffwll.ch>
Subject: Re: i915.ko WC writes are slow after ea8596bb2d8d379
Date: Thu, 19 Nov 2015 09:16:02 +0100	[thread overview]
Message-ID: <20151119081602.GC16214@gmail.com> (raw)
In-Reply-To: <20151118144811.GA1043@nuc-i3427.alporthouse.com>


* Chris Wilson <chris@chris-wilson.co.uk> wrote:

> > > A bisection pointed to 
> > > 
> > > commit ea8596bb2d8d37957f3e92db9511c50801689180
> > > Author: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
> > > Date:   Thu Jul 18 20:47:53 2013 +0900
> > > 
> > >     kprobes/x86: Remove unused text_poke_smp() and text_poke_smp_batch() functions
> > > 
> > > of which the active ingredient was just
> > > 
> > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> > > index b32ebf9..f4001e0 100644
> > > --- a/arch/x86/Kconfig
> > > +++ b/arch/x86/Kconfig
> > > @@ -2334,7 +2334,6 @@ config HAVE_ATOMIC_IOMAP
> > >  
> > >  config HAVE_TEXT_POKE_SMP
> > >         bool
> > > -       select STOP_MACHINE if SMP

Ouch...

This is certainly an educative example of how pure 'code removal' patches can have 
unintended side effects.

Is there a full fix patch available, and is anyone pushing that to Linus?

Thanks,

	Ingo

  parent reply	other threads:[~2015-11-19  8:16 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-08  9:03 Chris Wilson
2014-10-08 10:10 ` Chuck Ebbert
2014-10-08 19:49   ` Chris Wilson
2014-10-08 21:36     ` H. Peter Anvin
2014-10-09  6:53       ` Chris Wilson
2014-10-09 12:44         ` Chuck Ebbert
2014-10-09 13:00           ` Chris Wilson
2014-10-09 14:46             ` Chuck Ebbert
2014-10-09 15:14               ` Chris Wilson
2015-11-18 14:48   ` Chris Wilson
2015-11-18 15:57     ` Andy Lutomirski
2015-11-19  8:14       ` Ingo Molnar
2015-11-19 10:03         ` [PATCH] kernel: Remove stop_machine() Kconfig dependency Chris Wilson
2015-11-19  8:16     ` Ingo Molnar [this message]
2014-10-08 17:47 ` i915.ko WC writes are slow after ea8596bb2d8d379 Chuck Ebbert
2014-10-09  1:45   ` Masami Hiramatsu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20151119081602.GC16214@gmail.com \
    --to=mingo@kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=bpetkov@suse.de \
    --cc=cebbert.lkml@gmail.com \
    --cc=chris@chris-wilson.co.uk \
    --cc=daniel.vetter@ffwll.ch \
    --cc=hpa@linux.intel.com \
    --cc=jbaron@akamai.com \
    --cc=jkosina@suse.cz \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@amacapital.net \
    --cc=masami.hiramatsu.pt@hitachi.com \
    --cc=peterz@infradead.org \
    --cc=rostedt@goodmis.org \
    --cc=rusty@rustcorp.com.au \
    --cc=tj@kernel.org \
    --cc=yrl.pp-manager.tt@hitachi.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Powered by JetHome