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Subject: Re: [PATCH v2 2/5] ARM: vdso: Don't use gcc plugins for building
 vgettimeofday.c
To:     Luis Chamberlain <mcgrof@kernel.org>
Cc:     Kees Cook <keescook@chromium.org>, Jann Horn <jannh@google.com>,
        Emese Revfy <re.emese@gmail.com>,
        Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Michal Marek <michal.lkml@markovi.net>,
        Andrew Morton <akpm@linux-foundation.org>,
        Masahiro Yamada <yamada.masahiro@socionext.com>,
        Thiago Jung Bauermann <bauerman@linux.ibm.com>,
        Jessica Yu <jeyu@kernel.org>,
        Sven Schnelle <svens@stackframe.org>,
        Iurii Zaikin <yzaikin@google.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Vincenzo Frascino <vincenzo.frascino@arm.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Collingbourne <pcc@google.com>,
        Naohiro Aota <naohiro.aota@wdc.com>,
        Alexander Monakov <amonakov@ispras.ru>,
        Mathias Krause <minipli@googlemail.com>,
        PaX Team <pageexec@freemail.hu>,
        Brad Spengler <spender@grsecurity.net>,
        Laura Abbott <labbott@redhat.com>,
        Florian Weimer <fweimer@redhat.com>,
        kernel-hardening@lists.openwall.com, linux-kbuild@vger.kernel.org,
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References: <20200624123330.83226-1-alex.popov@linux.com>
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From:   Alexander Popov <alex.popov@linux.com>
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Message-ID: <f8d52f40-221b-5219-ca16-9d889252547a@linux.com>
Date:   Wed, 24 Jun 2020 15:56:54 +0300
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On 24.06.2020 15:52, Luis Chamberlain wrote:
> On Wed, Jun 24, 2020 at 03:33:27PM +0300, Alexander Popov wrote:
>> Don't use gcc plugins for building arch/arm/vdso/vgettimeofday.c to
>> avoid unneeded instrumentation.
>>
>> Signed-off-by: Alexander Popov <alex.popov@linux.com>
> 
> But why is skipping it safe?

Hello Luis,

Kees and Will discussed that in detail in v1 of the series:
https://lore.kernel.org/lkml/20200610073046.GA15939@willie-the-truck/

Best regards,
Alexander