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Date: Mon, 9 Mar 2015 18:48:25 +0100
From: Borislav Petkov <bp@suse.de>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>, Ingo Molnar <mingo@kernel.org>,
        Andy Lutomirski <luto@amacapital.net>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Pekka Riikonen <priikone@iki.fi>, Rik van Riel <riel@redhat.com>,
        Suresh Siddha <sbsiddha@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
        "Yu, Fenghua" <fenghua.yu@intel.com>,
        Quentin Casasnovas <quentin.casasnovas@oracle.com>
Subject: Re: [PATCH] x86/fpu: drop_fpu() should not assume that tsk == current
Message-ID: <20150309174825.GH12732@pd.tnic>
References: <54F74F59.5070107@intel.com>
 <20150309171041.GB11388@redhat.com>
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On Mon, Mar 09, 2015 at 06:10:41PM +0100, Oleg Nesterov wrote:
> drop_fpu() does clear_used_math() and usually this is correct because
> tsk == current. However switch_fpu_finish()->restore_fpu_checking() is
> called before it updates the "current_task" variable. If it fails, we

You mean here "... before __switch_to() updates the current_task ... ",
I assume?

-- 
Regards/Gruss,
    Boris.

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