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Date:   Tue, 24 May 2022 14:47:50 +0200
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Subject: Re: [PATCH] xen: switch gnttab_end_foreign_access() to take a struct
 page pointer
Content-Language: en-US
To:     Juergen Gross <jgross@suse.com>
Cc:     Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Stefano Stabellini <sstabellini@kernel.org>,
        =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= <roger.pau@citrix.com>,
        Jens Axboe <axboe@kernel.dk>,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Eric Van Hensbergen <ericvh@gmail.com>,
        Latchesar Ionkov <lucho@ionkov.net>,
        Dominique Martinet <asmadeus@codewreck.org>,
        Christian Schoenebeck <linux_oss@crudebyte.com>,
        xen-devel@lists.xenproject.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-input@vger.kernel.org,
        netdev@vger.kernel.org, v9fs-developer@lists.sourceforge.net
References: <20220524124137.10021-1-jgross@suse.com>
From:   Jan Beulich <jbeulich@suse.com>
In-Reply-To: <20220524124137.10021-1-jgross@suse.com>
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On 24.05.2022 14:41, Juergen Gross wrote:
> Instead of a virtual kernel address use a pointer of the associated
> struct page as second parameter of gnttab_end_foreign_access().
> 
> Most users have that pointer available already and are creating the
> virtual address from it, risking problems in case the memory is
> located in highmem.
> 
> gnttab_end_foreign_access() itself won't need to get the struct page
> from the address again.
> 
> Suggested-by: Jan Beulich <jbeulich@suse.com>
> Signed-off-by: Juergen Gross <jgross@suse.com>

Reviewed-by: Jan Beulich <jbeulich@suse.com>