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Date: Wed, 12 May 2021 10:50:41 +0200
From: 'Joerg Roedel' <joro@8bytes.org>
To: Juergen Gross <jgross@suse.com>
Cc: David Laight <David.Laight@aculab.com>,
	"x86@kernel.org" <x86@kernel.org>,
	Hyunwook Baek <baekhw@google.com>, Joerg Roedel <jroedel@suse.de>,
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Subject: Re: [PATCH 3/6] x86/sev-es: Use __put_user()/__get_user
Message-ID: <YJuW4TtRJKZ+OIhj@8bytes.org>
References: <20210512075445.18935-1-joro@8bytes.org>
 <20210512075445.18935-4-joro@8bytes.org>
 <0496626f018d4d27a8034a4822170222@AcuMS.aculab.com>
 <fcb2c501-70ca-1a54-4a75-8ab05c21ee30@suse.com>
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On Wed, May 12, 2021 at 10:16:12AM +0200, Juergen Gross wrote:
> You want something like xen_safe_[read|write]_ulong().

>From a first glance I can't see it, what is the difference between the
xen_safe_*_ulong() functions and __get_user()/__put_user()? The only
difference I can see is that __get/__put_user() support different access
sizes, but neither of those disables page-faults by itself, for example.

Couldn't these xen-specific functions not also be replaces by
__get_user()/__put_user()?

Regards,

	Joerg