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Date:   Fri, 23 Nov 2018 10:50:34 +0000
From:   Russell King - ARM Linux <linux@armlinux.org.uk>
To:     hpa@zytor.com
Cc:     Julien Thierry <julien.thierry@arm.com>,
        Ingo Molnar <mingo@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>,
        "linux-arm-kernel@lists.infradead.org" 
        <linux-arm-kernel@lists.infradead.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        James Morse <james.morse@arm.com>
Subject: Re: Sleeping in user_access section
Message-ID: <20181123105034.GQ30658@n2100.armlinux.org.uk>
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 <5B3B6AF9-9D8C-4577-905E-D407A5E7D0E3@zytor.com>
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On Fri, Nov 23, 2018 at 01:57:12AM -0800, hpa@zytor.com wrote:
> You should never call a sleeping function from a user_access section.
> It is intended for very limited regions.

So, what happens if the "unsafe" user access causes a page fault that
ends up sleeping?

-- 
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