From: Paolo Bonzini <pbonzini@redhat.com>
To: Alexey Kardashevskiy <aik@ozlabs.ru>,
"Hoyer, David" <David.Hoyer@netapp.com>,
"Qemu-devel@nongnu.org" <Qemu-devel@nongnu.org>
Cc: "Moyer, Keith" <Keith.Moyer@netapp.com>,
"Best, Tish" <Tish.Best@netapp.com>
Subject: Re: [Qemu-devel] e1000 memory corruption in guest OS
Date: Sat, 01 Mar 2014 22:31:55 +0100 [thread overview]
Message-ID: <531251CB.10102@redhat.com> (raw)
In-Reply-To: <5311D2DD.4090904@ozlabs.ru>
Il 01/03/2014 13:30, Alexey Kardashevskiy ha scritto:
>> >
>> > Corrupted DMA buffer is 0x e00000 -- 0x7f15c313f000.
>> > The e1000 packet is at 0x12ffac2 -- 0x7f15c313eac2.
>> >
>> > (0x7f15c313f000 - 0x7f15c313eac2) = 0x53e which is less than 0x5aa and
>> > (0x5aa - 0x53e) = 0x6c bytes get corrupted.
>> >
>> > I see here buffer overrun from e1000 and I suspect that your patch just
>> > hides this problem. What did I miss?
>
> Ping, anyone?
You missed that this is a Xen-specific problem. Xen maps things a page
at a time, so address_space_map/unmap/rw can operate only on a small
part of the requested [address, address+length) range.
So there is no overrun in e1000. The patch is incomplete, because it
fixes only address_space_rw, but the problem is indeed in exec.c.
Paolo
next prev parent reply other threads:[~2014-03-01 21:32 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-02-16 4:29 [Qemu-devel] e1000 memory corruption in guest OS Hoyer, David
2014-02-24 4:20 ` Alexey Kardashevskiy
2014-03-01 12:30 ` Alexey Kardashevskiy
2014-03-01 21:31 ` Paolo Bonzini [this message]
2014-03-03 1:58 ` Alexey Kardashevskiy
2014-03-03 8:33 ` Paolo Bonzini
2014-03-03 10:47 ` Alexey Kardashevskiy
2014-03-03 11:21 ` Paolo Bonzini
2014-03-03 21:33 ` Don Slutz
2014-03-03 22:53 ` Alexey Kardashevskiy
2014-02-24 14:02 ` Paolo Bonzini
2014-02-24 14:15 ` Hoyer, David
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