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Date: Tue, 16 Jun 2015 13:34:36 +0200
From: Borislav Petkov <bp@alien8.de>
To: Alexander Popov <alpopov@ptsecurity.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Andrey Konovalov <adech.fo@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Andrey Ryabinin <a.ryabinin@samsung.com>,
        Andy Lutomirski <luto@kernel.org>,
        Alexander Kuleshov <kuleshovmail@gmail.com>,
        Denys Vlasenko <dvlasenk@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Kees Cook <keescook@chromium.org>, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v5 1/2] x86_64: remove not needed clear_page for
 init_level4_page
Message-ID: <20150616113436.GG17786@pd.tnic>
References: <1433842921-18055-1-git-send-email-alpopov@ptsecurity.com>
 <1433842921-18055-2-git-send-email-alpopov@ptsecurity.com>
 <20150616111632.GF17786@pd.tnic>
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On Tue, Jun 16, 2015 at 01:16:32PM +0200, Borislav Petkov wrote:
> Now my hunch is that those entries get overwritten later but I wouldn't
> want to debug any strange bugs from leftovers in init_level4_pgt so
> having the clear_page() is actually a good thing.

So I guess we can do that:

#ifndef CONFIG_KASAN
        clear_page(init_level4_pgt);
#endif

Hmm...

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.
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