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Date:   Mon, 3 Dec 2018 23:08:41 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc:     Dave Hansen <dave.hansen@linux.intel.com>,
        Ingo Molnar <mingo@redhat.com>,
        the arch/x86 maintainers <x86@kernel.org>, nstange@suse.de,
        Rik van Riel <riel@surriel.com>,
        KVM devel mailing list <kvm@vger.kernel.org>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Andy Lutomirski <luto@kernel.org>,
        Borislav Petkov <bp@suse.de>,
        linux-efi <linux-efi@vger.kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        linux-tip-commits@vger.kernel.org
Subject: Re: [tip:x86/fpu] x86/fpu: Don't export __kernel_fpu_{begin,end}()
Message-ID: <20181203220841.GB4794@zn.tnic>
References: <20181129150210.2k4mawt37ow6c2vq@linutronix.de>
 <tip-7d79adb87fa79e4a4c59424fd5b5a922861fc5f6@git.kernel.org>
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On Mon, Dec 03, 2018 at 10:12:19PM +0100, Ard Biesheuvel wrote:
> > + * Using the FPU in hardirq is not allowed.
> 
> According to the documentation in x86/kernel/fpu/core.c, this is not
> true. So which one is accurate?

I think you mean the irq from user mode... Yap, we do allow that.

Sebastian?

Thx.

-- 
Regards/Gruss,
    Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.