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From:   Nick Desaulniers <ndesaulniers@google.com>
Date:   Thu, 24 May 2018 11:24:28 -0700
Message-ID: <CAKwvOdndRL6gs29eQQrL+bVNBt1fjrXS=mBgF4CRshz+J5LY-Q@mail.gmail.com>
Subject: Re: [clang] stack protector and f1f029c7bf
To:     hpa@zytor.com
Cc:     Alistair Strachan <astrachan@google.com>,
        Manoj Gupta <manojgupta@google.com>,
        Matthias Kaehlcke <mka@google.com>,
        Greg Hackmann <ghackmann@google.com>, sedat.dilek@gmail.com,
        tstellar@redhat.com, LKML <linux-kernel@vger.kernel.org>
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On Thu, May 24, 2018 at 11:20 AM <hpa@zytor.com> wrote:
> A stack canary on an *inlined* function? That's bound to break things
elsewhere too sooner or later.

But it's *not* inlined by GCC or Clang.

While the function is marked `static inline`, it's not in
arch/x86/kernel/paravirt.o due to:
arch/x86/kernel/paravirt.c:326

325 __visible struct pv_irq_ops pv_irq_ops = {

326         .save_fl = __PV_IS_CALLEE_SAVE(native_save_fl),

see comparison of disassembly  attached in:
https://bugs.llvm.org/attachment.cgi?id=20338
-- 
Thanks,
~Nick Desaulniers