From: Catalin Marinas <catalin.marinas@arm.com>
To: Will Deacon <will@kernel.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>,
linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, ard.biesheuvel@linaro.org,
ndesaulniers@google.com, tglx@linutronix.de
Subject: Re: [PATCH v3 1/5] arm64: vdso32: Introduce COMPAT_CC_IS_GCC
Date: Tue, 1 Oct 2019 16:30:56 +0100 [thread overview]
Message-ID: <20191001153056.GO41399@arrakis.emea.arm.com> (raw)
In-Reply-To: <20191001144353.5rn3bkcc6eyfclh7@willie-the-truck>
On Tue, Oct 01, 2019 at 03:43:54PM +0100, Will Deacon wrote:
> > >>>> On Thu, Sep 26, 2019 at 10:43:38PM +0100, Vincenzo Frascino wrote:
> > >>>>> +config COMPATCC_IS_ARM_GCC
> > >>>>> + def_bool $(success,$(COMPATCC) --version | head -n 1 | grep -q "arm-.*-gcc")
[...]
> My point was that we don't attempt to sanitise the compiler passed via
> CROSS_COMPILE, so I don't think we should do anything special for COMPATCC
> either.
What I really want from kbuild with this patch is:
1. Not to warn me that I don't have a CROSS_COMPILE_COMPAT set
2. Not to give me a compilation error if the makefile made up a COMPATCC
that doesn't work
Since we dropped the Kconfig option for the compat gcc prefix (which I
didn't like anyway), COMPATCC is now initialised to
(CROSS_COMPILE_COMPAT)gcc. This means that it is valid compiler (and
it's an aarch64 compiler on my machine). The COMPATCC_IS_ARM_GCC
silently disables the compat vDSO for this case rather than giving me a
build error if we don't have such checks.
In the long run, I wouldn't mandate CROSS_COMPILE_COMPAT to always be
set for the compat vDSO since with clang we could use the same compiler
binary for both native and compat (with different flags). That's once we
cleaned up the headers.
So, I think the best option for the time being is to check that the
compat compiler is an "arm*-gcc", otherwise disable the compat vDSO.
--
Catalin
WARNING: multiple messages have this Message-ID (diff)
From: Catalin Marinas <catalin.marinas@arm.com>
To: Will Deacon <will@kernel.org>
Cc: ard.biesheuvel@linaro.org, ndesaulniers@google.com,
linux-kernel@vger.kernel.org, tglx@linutronix.de,
Vincenzo Frascino <vincenzo.frascino@arm.com>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v3 1/5] arm64: vdso32: Introduce COMPAT_CC_IS_GCC
Date: Tue, 1 Oct 2019 16:30:56 +0100 [thread overview]
Message-ID: <20191001153056.GO41399@arrakis.emea.arm.com> (raw)
In-Reply-To: <20191001144353.5rn3bkcc6eyfclh7@willie-the-truck>
On Tue, Oct 01, 2019 at 03:43:54PM +0100, Will Deacon wrote:
> > >>>> On Thu, Sep 26, 2019 at 10:43:38PM +0100, Vincenzo Frascino wrote:
> > >>>>> +config COMPATCC_IS_ARM_GCC
> > >>>>> + def_bool $(success,$(COMPATCC) --version | head -n 1 | grep -q "arm-.*-gcc")
[...]
> My point was that we don't attempt to sanitise the compiler passed via
> CROSS_COMPILE, so I don't think we should do anything special for COMPATCC
> either.
What I really want from kbuild with this patch is:
1. Not to warn me that I don't have a CROSS_COMPILE_COMPAT set
2. Not to give me a compilation error if the makefile made up a COMPATCC
that doesn't work
Since we dropped the Kconfig option for the compat gcc prefix (which I
didn't like anyway), COMPATCC is now initialised to
(CROSS_COMPILE_COMPAT)gcc. This means that it is valid compiler (and
it's an aarch64 compiler on my machine). The COMPATCC_IS_ARM_GCC
silently disables the compat vDSO for this case rather than giving me a
build error if we don't have such checks.
In the long run, I wouldn't mandate CROSS_COMPILE_COMPAT to always be
set for the compat vDSO since with clang we could use the same compiler
binary for both native and compat (with different flags). That's once we
cleaned up the headers.
So, I think the best option for the time being is to check that the
compat compiler is an "arm*-gcc", otherwise disable the compat vDSO.
--
Catalin
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-10-01 15:31 UTC|newest]
Thread overview: 127+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-20 14:27 Problems with arm64 compat vdso Will Deacon
2019-09-20 16:33 ` Vincenzo Frascino
2019-09-23 16:41 ` Ard Biesheuvel
2019-09-24 12:11 ` Vincenzo Frascino
2019-09-24 18:06 ` Nick Desaulniers
2019-09-24 20:42 ` Vincenzo Frascino
2019-09-25 15:58 ` Ard Biesheuvel
2019-09-26 6:03 ` [PATCH 0/4] arm64: vdso32: Address various issues Vincenzo Frascino
2019-09-26 6:03 ` Vincenzo Frascino
2019-09-26 6:03 ` [PATCH 1/4] arm64: vdso32: Introduce COMPAT_CC_IS_GCC Vincenzo Frascino
2019-09-26 6:03 ` Vincenzo Frascino
2019-09-26 8:06 ` Catalin Marinas
2019-09-26 8:06 ` Catalin Marinas
2019-09-26 10:56 ` Vincenzo Frascino
2019-09-26 10:56 ` Vincenzo Frascino
2019-09-26 11:02 ` Vincenzo Frascino
2019-09-26 11:02 ` Vincenzo Frascino
2019-09-26 15:23 ` Catalin Marinas
2019-09-26 15:23 ` Catalin Marinas
2019-09-26 12:22 ` Vincenzo Frascino
2019-09-26 12:22 ` Vincenzo Frascino
2019-09-26 15:17 ` Catalin Marinas
2019-09-26 15:17 ` Catalin Marinas
2019-09-26 20:17 ` Vincenzo Frascino
2019-09-26 20:17 ` Vincenzo Frascino
2019-09-26 6:03 ` [PATCH 2/4] arm64: vdso32: Detect binutils support for dmb ishld Vincenzo Frascino
2019-09-26 6:03 ` Vincenzo Frascino
2019-09-26 8:30 ` Catalin Marinas
2019-09-26 8:30 ` Catalin Marinas
2019-09-26 10:59 ` Vincenzo Frascino
2019-09-26 10:59 ` Vincenzo Frascino
2019-09-26 6:03 ` [PATCH 3/4] arm64: vdso32: Fix compilation warning Vincenzo Frascino
2019-09-26 6:03 ` Vincenzo Frascino
2019-09-26 8:32 ` Catalin Marinas
2019-09-26 8:32 ` Catalin Marinas
2019-09-26 11:03 ` Vincenzo Frascino
2019-09-26 11:03 ` Vincenzo Frascino
2019-09-26 6:03 ` [PATCH 4/4] arm64: Remove gettimeofday.S Vincenzo Frascino
2019-09-26 6:03 ` Vincenzo Frascino
2019-09-26 8:34 ` Catalin Marinas
2019-09-26 8:34 ` Catalin Marinas
2019-09-26 13:38 ` [PATCH v2 0/4] arm64: vdso32: Address various issues Vincenzo Frascino
2019-09-26 13:38 ` Vincenzo Frascino
2019-09-26 13:38 ` [PATCH v2 1/4] arm64: vdso32: Introduce COMPAT_CC_IS_GCC Vincenzo Frascino
2019-09-26 13:38 ` Vincenzo Frascino
2019-09-26 15:13 ` Catalin Marinas
2019-09-26 15:13 ` Catalin Marinas
2019-09-26 13:38 ` [PATCH v2 2/4] arm64: vdso32: Detect binutils support for dmb ishld Vincenzo Frascino
2019-09-26 13:38 ` Vincenzo Frascino
2019-09-26 14:26 ` Catalin Marinas
2019-09-26 14:26 ` Catalin Marinas
2019-09-26 20:19 ` Vincenzo Frascino
2019-09-26 20:19 ` Vincenzo Frascino
2019-09-26 15:59 ` Catalin Marinas
2019-09-26 15:59 ` Catalin Marinas
2019-09-26 21:17 ` Vincenzo Frascino
2019-09-26 21:17 ` Vincenzo Frascino
2019-09-26 16:23 ` Nick Desaulniers
2019-09-26 16:23 ` Nick Desaulniers
2019-09-26 13:38 ` [PATCH v2 3/4] arm64: vdso32: Fix compilation warning Vincenzo Frascino
2019-09-26 13:38 ` Vincenzo Frascino
2019-09-26 15:22 ` Catalin Marinas
2019-09-26 15:22 ` Catalin Marinas
2019-09-26 13:38 ` [PATCH v2 4/4] arm64: Remove gettimeofday.S Vincenzo Frascino
2019-09-26 13:38 ` Vincenzo Frascino
2019-09-26 15:31 ` [PATCH v2 0/4] arm64: vdso32: Address various issues Catalin Marinas
2019-09-26 15:31 ` Catalin Marinas
2019-09-26 20:29 ` Vincenzo Frascino
2019-09-26 20:29 ` Vincenzo Frascino
2019-09-26 21:43 ` [PATCH v3 0/5]arm64: " Vincenzo Frascino
2019-09-26 21:43 ` Vincenzo Frascino
2019-09-26 21:43 ` [PATCH v3 1/5] arm64: vdso32: Introduce COMPAT_CC_IS_GCC Vincenzo Frascino
2019-09-26 21:43 ` Vincenzo Frascino
2019-09-27 9:24 ` Catalin Marinas
2019-09-27 9:24 ` Catalin Marinas
2019-10-01 13:14 ` Will Deacon
2019-10-01 13:14 ` Will Deacon
2019-10-01 13:27 ` Catalin Marinas
2019-10-01 13:27 ` Catalin Marinas
2019-10-01 14:20 ` Vincenzo Frascino
2019-10-01 14:20 ` Vincenzo Frascino
2019-10-01 14:20 ` Will Deacon
2019-10-01 14:20 ` Will Deacon
2019-10-01 14:37 ` Vincenzo Frascino
2019-10-01 14:37 ` Vincenzo Frascino
2019-10-01 14:43 ` Will Deacon
2019-10-01 14:43 ` Will Deacon
2019-10-01 14:59 ` Vincenzo Frascino
2019-10-01 14:59 ` Vincenzo Frascino
2019-10-01 15:30 ` Catalin Marinas [this message]
2019-10-01 15:30 ` Catalin Marinas
2019-10-01 16:46 ` Will Deacon
2019-10-01 16:46 ` Will Deacon
2019-10-01 16:59 ` Nick Desaulniers
2019-10-01 16:59 ` Nick Desaulniers
2019-10-01 17:07 ` Will Deacon
2019-10-01 17:07 ` Will Deacon
2019-10-01 17:12 ` Nick Desaulniers
2019-10-01 17:12 ` Nick Desaulniers
2019-10-01 17:14 ` Will Deacon
2019-10-01 17:14 ` Will Deacon
2019-09-26 21:43 ` [PATCH v3 2/5] arm64: vdso32: Detect binutils support for dmb ishld Vincenzo Frascino
2019-09-26 21:43 ` Vincenzo Frascino
2019-09-27 9:25 ` Catalin Marinas
2019-09-27 9:25 ` Catalin Marinas
2019-10-01 13:26 ` Will Deacon
2019-10-01 13:26 ` Will Deacon
2019-10-01 14:23 ` Vincenzo Frascino
2019-10-01 14:23 ` Vincenzo Frascino
2019-09-26 21:43 ` [PATCH v3 3/5] arm64: vdso32: Fix compilation warning Vincenzo Frascino
2019-09-26 21:43 ` Vincenzo Frascino
2019-09-27 9:26 ` Catalin Marinas
2019-09-27 9:26 ` Catalin Marinas
2019-10-01 13:21 ` Will Deacon
2019-10-01 13:21 ` Will Deacon
2019-10-01 14:41 ` Vincenzo Frascino
2019-10-01 14:41 ` Vincenzo Frascino
2019-09-26 21:43 ` [PATCH v3 4/5] arm64: Remove gettimeofday.S Vincenzo Frascino
2019-09-26 21:43 ` Vincenzo Frascino
2019-09-26 21:43 ` [PATCH v3 5/5] arm64: vdso32: Remove jump label config option in Makefile Vincenzo Frascino
2019-09-26 21:43 ` Vincenzo Frascino
2019-09-27 9:27 ` Catalin Marinas
2019-09-27 9:27 ` Catalin Marinas
2019-09-27 10:46 ` [PATCH v3 0/5]arm64: vdso32: Address various issues Catalin Marinas
2019-09-27 10:46 ` Catalin Marinas
2019-10-01 13:27 ` Will Deacon
2019-10-01 13:27 ` Will Deacon
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=20191001153056.GO41399@arrakis.emea.arm.com \
--to=catalin.marinas@arm.com \
--cc=ard.biesheuvel@linaro.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=ndesaulniers@google.com \
--cc=tglx@linutronix.de \
--cc=vincenzo.frascino@arm.com \
--cc=will@kernel.org \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.