From: "Hervé Poussineau" <hpoussin@reactos.org>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Hervé Poussineau" <hpoussin@reactos.org>,
qemu-devel@nongnu.org, "Anthony Liguori" <aliguori@amazon.com>,
"Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [Qemu-devel] [PATCH 0/2] PC: improve emulation correctness
Date: Wed, 05 Mar 2014 22:48:24 +0100 [thread overview]
Message-ID: <53179BA8.5050405@reactos.org> (raw)
In-Reply-To: <5316DD1D.1030200@redhat.com>
Le 05/03/2014 09:15, Paolo Bonzini a écrit :
> Il 05/03/2014 00:49, Michael S. Tsirkin ha scritto:
>> On Mon, Mar 03, 2014 at 11:05:17PM +0100, Hervé Poussineau wrote:
>>> Ping.
>>>
>>> QEMU crash at reboot is due to not resetting PAM registers at i440fx
>>> reset, but a patch has already been rejected on ML:
>>> http://lists.gnu.org/archive/html/qemu-devel/2013-02/msg02928.html
>>>
>>> Hervé
>>
>> I thought an alternative fix is being worked on?
>> http://lists.gnu.org/archive/html/qemu-devel/2013-02/msg02967.html
>
> Hervé, how does the BIOS do the reset?
>
> Paolo
At cold boot, BIOS is shadowed to RAM, and then hot-patched, so a warm boot won't do the same thing.
At BIOS exit, BIOS jumps to the new warm boot path.
This warm path doesn't work and crashes QEMU with "qemu: fatal: Trying to execute code outside RAM or ROM at 0x000a1249" ; I've no idea why exactly.
Resetting PAM registers prevents the shadowed copy to be visible, and BIOS does again a cold boot, which works.
Hervé
next prev parent reply other threads:[~2014-03-05 21:49 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-02-11 22:46 [Qemu-devel] [PATCH 0/2] PC: improve emulation correctness Hervé Poussineau
2014-02-11 22:46 ` [Qemu-devel] [PATCH 1/2] pam: partly fix write-only mode Hervé Poussineau
2014-02-11 22:46 ` [Qemu-devel] [PATCH 2/2] pckbd: return 'keyboard enabled' on read input port command Hervé Poussineau
2014-03-03 22:05 ` [Qemu-devel] [PATCH 0/2] PC: improve emulation correctness Hervé Poussineau
2014-03-04 23:49 ` Michael S. Tsirkin
2014-03-05 8:15 ` Paolo Bonzini
2014-03-05 21:48 ` Hervé Poussineau [this message]
2014-03-05 18:50 ` Andreas Färber
2014-03-05 21:47 ` Hervé Poussineau
2014-03-05 18:46 ` Michael S. Tsirkin
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