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Date:   Thu, 14 May 2020 20:14:21 +0530
From:   afzal mohammed <afzal.mohd.ma@gmail.com>
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Russell King <linux@armlinux.org.uk>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: ARM: static kernel in vmalloc space
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Hi,

On Thu, May 14, 2020 at 07:05:45PM +0530, afzal mohammed wrote:

> So if we make VMSPLIT_4G_4G, depends on !HIGH_MEMORY (w/ mention of
> caveat in Kconfig help that this is meant for platforms w/ <=4GB), then
> we can do copy_{from,to}_user the same way currently do, and no need to
> do the user page pinning & kmap, right ?

i think user page pinning is still required, but kmap can be avoided
by using lowmem corresponding to that page, right ?, or am i
completely wrong ?

Regards
afzal