From: Paolo Bonzini <pbonzini@redhat.com>
To: George Dunlap <george.dunlap@eu.citrix.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com>,
Stefano Stabellini <stefano.stabellini@eu.citrix.com>,
Ian Jackson <Ian.Jackson@eu.citrix.com>,
"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
xen-devel <xen-devel@lists.xen.org>,
Alex Bligh <alex@alex.org.uk>,
Anthony Liguori <anthony@codemonkey.ws>
Subject: Re: [Qemu-devel] [Xen-devel] [PATCHv3] QEMU(upstream): Disable xen's use of O_DIRECT by default as it results in crashes.
Date: Wed, 20 Mar 2013 12:08:19 +0100 [thread overview]
Message-ID: <514998A3.9090903@redhat.com> (raw)
In-Reply-To: <51499157.2060202@eu.citrix.com>
Il 20/03/2013 11:37, George Dunlap ha scritto:
>> That is true. My guess is that nobody really migrates HVM guests without
>> PV drivers installed (it's not even possible on XenServer but xl let you
>> do that if you want to). When the PV drivers initialize at boot time,
>> the IDE disk is closed. Therefore we wouldn't have this problem.
>>
>> Maybe we should prevent HVM guest migration without PV drivers with xl
>> too. Ian, what do you think?
>
> We should be able to make it safe if we just make sure that qemu does a
> metadata sync / FS sync when we ask qemu to write the save file.
To make it safe, just use cache=none. There are downsides (for example
tmpfs does not support it), but perhaps you can use a global option or
environment variable to toggle the behavior.
Is xl still using the driver:subdriver:/path,readonly syntax? That's
really inflexible compared to libvirt's XML...
Paolo
next prev parent reply other threads:[~2013-03-20 11:08 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-18 12:18 [Qemu-devel] [PATCHv3] QEMU(upstream): Disable xen's use of O_DIRECT by default as it results in crashes Alex Bligh
2013-03-18 13:03 ` Stefan Hajnoczi
2013-03-18 13:19 ` Alex Bligh
2013-03-18 13:32 ` Paolo Bonzini
2013-03-18 13:49 ` Alex Bligh
2013-03-18 14:05 ` Paolo Bonzini
2013-03-18 14:30 ` Alex Bligh
2013-03-18 14:49 ` Paolo Bonzini
2013-03-18 15:40 ` Alex Bligh
2013-03-18 16:19 ` Paolo Bonzini
2013-03-18 16:53 ` Alex Bligh
2013-03-18 17:38 ` George Dunlap
2013-03-18 17:47 ` Alex Bligh
2013-03-18 18:00 ` Paolo Bonzini
2013-03-19 10:06 ` [Qemu-devel] [Xen-devel] " George Dunlap
2013-03-19 10:43 ` Paolo Bonzini
2013-03-19 10:51 ` George Dunlap
2013-03-19 11:14 ` Paolo Bonzini
2013-03-19 11:21 ` George Dunlap
2013-03-19 15:12 ` George Dunlap
2013-03-19 15:29 ` George Dunlap
2013-03-19 19:15 ` Alex Bligh
2013-03-20 10:24 ` Stefano Stabellini
2013-03-20 10:37 ` George Dunlap
2013-03-20 11:08 ` Paolo Bonzini [this message]
2013-03-20 11:20 ` Alex Bligh
2013-03-20 11:57 ` David Scott
2013-03-19 11:44 ` Alex Bligh
2013-03-19 11:49 ` Paolo Bonzini
2013-03-19 15:13 ` Stefano Stabellini
2013-03-19 16:53 ` Paolo Bonzini
2013-03-19 17:03 ` Stefano Stabellini
2013-03-20 8:33 ` Alex Bligh
2013-03-20 9:26 ` Paolo Bonzini
2013-03-29 17:19 ` Stefano Stabellini
2013-03-31 19:53 ` Alex Bligh
2013-04-01 15:32 ` [Qemu-devel] [PATCH] [RFC] Xen PV backend: Move call to bdrv_new from blk_init to blk_connect Alex Bligh
2013-04-01 15:44 ` Stefano Stabellini
2013-04-01 20:56 ` Alex Bligh
2013-04-02 11:08 ` Stefano Stabellini
2013-04-05 10:31 ` [Qemu-devel] [PATCHv2 1/2] " Alex Bligh
2013-04-05 10:31 ` [Qemu-devel] [PATCHv2 2/2] Xen PV backend: Disable use of O_DIRECT by default as it results in crashes Alex Bligh
2013-04-05 14:22 ` [Qemu-devel] [PATCHv2 1/2] Xen PV backend: Move call to bdrv_new from blk_init to blk_connect Stefano Stabellini
2013-04-05 15:42 ` [Qemu-devel] [PATCHv3 " Alex Bligh
2013-04-05 15:42 ` [Qemu-devel] [PATCHv3 2/2] Xen PV backend: Disable use of O_DIRECT by default as it results in crashes Alex Bligh
2013-04-05 15:43 ` [Qemu-devel] [PATCHv2 1/2] Xen PV backend: Move call to bdrv_new from blk_init to blk_connect Alex Bligh
2013-04-05 10:32 ` [Qemu-devel] [PATCHv2 1/2] Xen PV backend (for qemu-upstream-4.2-testing): " Alex Bligh
2013-04-05 10:32 ` [Qemu-devel] [PATCHv2 2/2] Xen PV backend (for qemu-upstream-4.2-testing): Disable use of O_DIRECT by default as it results in crashes Alex Bligh
2013-04-05 10:34 ` [Qemu-devel] [PATCH] [RFC] Xen PV backend: Move call to bdrv_new from blk_init to blk_connect Alex Bligh
2013-04-01 16:35 ` [Qemu-devel] [Xen-devel] [PATCHv3] QEMU(upstream): Disable xen's use of O_DIRECT by default as it results in crashes Alex Bligh
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