linux-kernel - Re: Sleeping in user

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Message-ID: <20181123105034.GQ30658@n2100.armlinux.org.uk>
Date:   Fri, 23 Nov 2018 10:50:34 +0000
From:   Russell King - ARM Linux <linux@...linux.org.uk>
To:     hpa@...or.com
Cc:     Julien Thierry <julien.thierry@....com>,
        Ingo Molnar <mingo@...hat.com>,
        LKML <linux-kernel@...r.kernel.org>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        Catalin Marinas <catalin.marinas@....com>,
        Will Deacon <will.deacon@....com>,
        James Morse <james.morse@....com>
Subject: Re: Sleeping in user_access section

On Fri, Nov 23, 2018 at 01:57:12AM -0800, hpa@...or.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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