From: Russell King - ARM Linux admin <linux@armlinux.org.uk>
To: Nick Desaulniers <ndesaulniers@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Darren Hart <dvhart@infradead.org>,
Mikael Pettersson <mikpe@it.uu.se>,
Mikael Pettersson <mikpelinux@gmail.com>,
Dave Martin <Dave.Martin@arm.com>,
Linux ARM <linux-arm-kernel@lists.infradead.org>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/2] ARM: futex: make futex_detect_cmpxchg more reliable
Date: Fri, 8 Mar 2019 09:54:07 +0000 [thread overview]
Message-ID: <20190308095407.zfezalaysgjialpy@shell.armlinux.org.uk> (raw)
In-Reply-To: <CAKwvOdnTLSUmuwtJTGqZpiu9DfRoK8NW88CaouezqZ-y8RDmmg@mail.gmail.com>
On Thu, Mar 07, 2019 at 04:04:23PM -0800, Nick Desaulniers wrote:
> On Thu, Mar 7, 2019 at 3:49 PM Russell King - ARM Linux admin
> <linux@armlinux.org.uk> wrote:
> >
> > On Thu, Mar 07, 2019 at 11:39:08AM -0800, Nick Desaulniers wrote:
> > > Underspecification of constraints to extended inline assembly is a
> > > common issue exposed by other compilers (and possibly but in-effect
> > > infrequently compiler upgrades).
> >
> > I don't see what is "underspecified" in the original constraints.
> > Please explain.
>
> From the link:
>
> The problem is that in the T(streq) insn, %3 and %4 MUST be different registers,
> but nothing in the asm() constrains them to be different.
Thanks, but that is not what I'm asking. See my reply to Ard.
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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next prev parent reply other threads:[~2019-03-08 9:54 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-07 9:14 [PATCH 1/2] futex: mark futex_detect_cmpxchg() as 'noinline' Arnd Bergmann
2019-03-07 9:14 ` [PATCH 2/2] ARM: futex: make futex_detect_cmpxchg more reliable Arnd Bergmann
2019-03-07 19:39 ` Nick Desaulniers
2019-03-07 23:48 ` Russell King - ARM Linux admin
2019-03-08 0:04 ` Nick Desaulniers
2019-03-08 9:54 ` Russell King - ARM Linux admin [this message]
2019-03-08 8:57 ` Ard Biesheuvel
2019-03-08 9:53 ` Russell King - ARM Linux admin
2019-03-08 10:08 ` Ard Biesheuvel
2019-03-08 10:16 ` Ard Biesheuvel
2019-03-08 10:56 ` Russell King - ARM Linux admin
2019-03-08 10:34 ` Russell King - ARM Linux admin
2019-03-08 10:45 ` Ard Biesheuvel
2019-03-08 10:58 ` Russell King - ARM Linux admin
2019-03-08 11:55 ` Ard Biesheuvel
2019-03-11 14:34 ` Arnd Bergmann
2019-03-11 14:36 ` Ard Biesheuvel
2019-03-11 16:29 ` Arnd Bergmann
2019-03-11 16:36 ` Ard Biesheuvel
2019-03-11 20:58 ` Arnd Bergmann
2019-03-08 11:55 ` Dave Martin
2019-03-07 17:19 ` [PATCH 1/2] futex: mark futex_detect_cmpxchg() as 'noinline' Joe Perches
2019-03-07 17:25 ` Russell King - ARM Linux admin
2019-03-07 17:42 ` Joe Perches
2019-03-07 18:07 ` Russell King - ARM Linux admin
2019-03-07 18:12 ` Nick Desaulniers
2019-03-07 18:21 ` Nathan Chancellor
2019-03-07 22:24 ` Arnd Bergmann
2020-12-12 12:26 ` Marco Elver
2020-12-12 20:01 ` Thomas Gleixner
2020-12-14 10:22 ` Marco Elver
2020-12-14 13:15 ` Arnd Bergmann
2020-12-15 6:09 ` Guo Ren
2020-12-15 11:26 ` Arnd Bergmann
2020-12-15 19:38 ` Sam Ravnborg
2020-12-15 23:24 ` Arnd Bergmann
2020-12-17 15:32 ` Andreas Larsson
2020-12-17 16:43 ` Arnd Bergmann
2020-12-18 11:08 ` Andreas Larsson
2020-12-17 20:03 ` Sam Ravnborg
2020-12-16 10:07 ` David Laight
2020-12-16 11:40 ` Peter Zijlstra
2020-12-20 15:44 ` Guo Ren
2020-12-20 17:49 ` Arnd Bergmann
2020-12-21 2:58 ` Guo Ren
2021-07-22 20:05 ` Nathan Chancellor
2021-10-25 13:52 ` Arnd Bergmann
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