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Date:   Tue, 15 Sep 2020 20:27:30 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Roman Kiryanov <rkir@google.com>
Cc:     rjw@rjwysocki.net, pavel@ucw.cz,
        Thomas Gleixner <tglx@linutronix.de>, mingo@redhat.com,
        x86@kernel.org, linux-pm@vger.kernel.org,
        Greg KH <gregkh@linuxfoundation.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Alistair Delva <adelva@google.com>,
        Haitao Shan <hshan@google.com>,
        lkml <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] arch: x86: power: cpu: init %gs before
 __restore_processor_state (clang)
Message-ID: <20200915182730.GW14436@zn.tnic>
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 <20200915174643.GT14436@zn.tnic>
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On Tue, Sep 15, 2020 at 10:57:16AM -0700, Roman Kiryanov wrote:
> I believe the kernel makes a questionable assumption on how clang
> uses registers (gs will not be used if stack protection is disabled).
> Both kernel and clang behaves unfortunate here.

If the kernel is at fault here and this same thing happens with GCC,
sure, but this is a clang-specific fix.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette