From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Andrew Lutomirski <luto@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>, Andy Lutomirski <luto@amacapital.net>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Zhang Rui <rui.zhang@intel.com>, Thomas Gleixner <tglx@linutronix.de>,
        Jarkko Nikula <jarkko.nikula@linux.intel.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        the arch/x86 maintainers <x86@kernel.org>
Subject: Re: [PATCH] Fix resume on x86-32 machines
Date: Mon, 11 Dec 2017 15:43:28 +0100
Message-ID: <5321270.nZsYpZjJZb@aspire.rjw.lan>
In-Reply-To: <151331264.Sjvx2oHGGq@aspire.rjw.lan>
References: <2809506.pL8kVbvXcY@aspire.rjw.lan> <76028A95-1CE1-49AA-9929-9C15FFC520EB@amacapital.net> <151331264.Sjvx2oHGGq@aspire.rjw.lan>
MIME-Version: 1.0
Content-Transfer-Encoding: 7Bit
Content-Type: text/plain; charset="us-ascii"
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 781
Lines: 20

On Monday, December 11, 2017 3:22:39 PM CET Rafael J. Wysocki wrote:
> On Sunday, December 10, 2017 10:58:23 PM CET Andy Lutomirski wrote:
> > 
> > > On Dec 10, 2017, at 1:38 PM, Pavel Machek <pavel@ucw.cz> wrote:
> > > 
> > > 
> > > After 4.15-rc2, suspend stopped working on Thinkpad X60. 5b06bbc
> > > (unintentionally?) reordered stuff with respect to
> > > fix_processor_context() on 32-bit and 64-bit. We undo that change on
> > > 32-bit.
> > > 
> > 
> > Can you explain what was wrong with the reordering?  Your patch certainly *looks* incorrect.
> > 
> > I'm guessing that the real issue is that 32-bit needs %fs restored early for TLS.
> 
> I *think* you are right.

Hmm.  Don't we need to restore GS on 32-bit before doing the per_cpu() thing
in fix_processor_context()?