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Date: Wed, 2 May 2018 18:36:46 +0300
From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
To: Andrey Konovalov <andreyknvl@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>, Jonathan Corbet <corbet@lwn.net>,
	Mark Rutland <mark.rutland@arm.com>,
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Subject: Re: [PATCH 4/6] mm, arm64: untag user addresses in mm/gup.c
Message-ID: <20180502153645.fui4ju3scsze3zkq@black.fi.intel.com>
References: <cover.1524077494.git.andreyknvl@google.com>
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On Wed, May 02, 2018 at 02:38:42PM +0000, Andrey Konovalov wrote:
> > Does having a tagged address here makes any difference? I couldn't hit a
> > failure with my simple tests (LD_PRELOAD a library that randomly adds
> > tags to pointers returned by malloc).
> 
> I think you're right, follow_page_mask is only called from
> __get_user_pages, which already untagged the address. I'll remove
> untagging here.

It also called from follow_page(). Have you covered all its callers?

-- 
 Kirill A. Shutemov