From: Ian Campbell <Ian.Campbell@citrix.com>
To: Anh Dinh <ug93tad@gmail.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>,
"<xen-devel@lists.xen.org>" <xen-devel@lists.xen.org>
Subject: Re: how to deal with copy_to_user returning non zero
Date: Mon, 10 Nov 2014 10:04:08 +0000 [thread overview]
Message-ID: <1415613848.27002.3.camel@citrix.com> (raw)
In-Reply-To: <CAAbkU4SUrk0nRT97T0eBqNB7-Z7MVLGoWJtP+DwPijbZEphM0w@mail.gmail.com>
On Sun, 2014-11-09 at 09:22 +0800, Anh Dinh wrote:
> Thanks,
>
>
> I've found out the reason it page-faulting is because I used malloc()
> to allocate the output buffer, which turns out to allocate lazily.
> Therefore the hypervisor page-fault because the memory is still
> waiting to be mapped by the kernel.
>
>
> I simply touched all the allocated memory, and it works fine now.
It might work, but unless it is using hypercall buffers and
XEN_GUEST_HANDLE then it is still subtly broken.
Ian.
prev parent reply other threads:[~2014-11-10 10:04 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-07 10:38 how to deal with copy_to_user returning non zero Anh Dinh
2014-11-07 10:44 ` Andrew Cooper
2014-11-07 10:57 ` And Dinh
2014-11-07 11:01 ` Andrew Cooper
2014-11-09 1:22 ` Anh Dinh
2014-11-10 10:04 ` Ian Campbell [this message]
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