Re: [Xen-devel] [PATCH] qemu-xen-3.4-testing: Fix read-only image file handling

[Keir Fraser <keir.fraser@xxxxxxxxxxxxx>]

You need to bring your qemu repo up to date. Throw it away, or go into it
and 'git pull -a'.

 -- Keir

On 04/06/2010 14:00, "Michal Novotny" <minovotn@xxxxxxxxxx> wrote:

> Well, now the kernel is booting but when I'm trying to recompile tools
> and stubdom images it's not OK returning those errors:
> 
> ...
> qemu successfuly configured for Xen qemu-dm build
> make -C ioemu-dir install
> === PCI passthrough capability has been enabled ===
> make[3]: Entering directory
> `/home2/shared/xen-unstable.hg/tools/ioemu-remote'
> === PCI passthrough capability has been enabled ===
> === PCI passthrough capability has been enabled ===
> make[4]: Entering directory
> `/home2/shared/xen-unstable.hg/tools/ioemu-remote/i386-dm'
> CC i386-dm/vl.o
> /home2/shared/xen-unstable.hg/tools/ioemu-dir/vl.c: In function ?main¹:
> /home2/shared/xen-unstable.hg/tools/ioemu-dir/vl.c:5729: warning:
> implicit declaration of function ?dma_helper_init¹
> /home2/shared/xen-unstable.hg/tools/ioemu-dir/vl.c:5731: error: too few
> arguments to function ?xc_interface_open¹
> make[4]: *** [vl.o] Error 1
> make[4]: Leaving directory
> `/home2/shared/xen-unstable.hg/tools/ioemu-remote/i386-dm'
> make[3]: *** [subdir-i386-dm] Error 2
> make[3]: Leaving directory
> `/home2/shared/xen-unstable.hg/tools/ioemu-remote'
> make[2]: *** [subdir-install-ioemu-dir] Error 2
> make[2]: Leaving directory `/home2/shared/xen-unstable.hg/tools'
> make[1]: *** [subdirs-install] Error 2
> make[1]: Leaving directory `/home2/shared/xen-unstable.hg/tools'
> make: *** [install-tools] Error 2
> #
> 
> The command I used for compilation is `make install-xen && make
> install-tools && make install-stubdom && make install-docs` on the
> latest updated xen-unstable staging mercurial tree so I need to
> investigate this further. Nevertheless, the dom0 2.6.31.13 is booting on
> RHEL-5 which is good. That links you gave me Pasi helped, thanks! Now I
> need to resolve those tools issues.
> 
> Michal
> 
> On 06/04/2010 12:57 PM, Michal Novotny wrote:
>> On 06/04/2010 12:42 PM, Pasi Kärkkäinen wrote:
>>> On Fri, Jun 04, 2010 at 11:37:51AM +0200, Michal Novotny wrote:
>>>> Oh, one more thing I've discovered now. Since the codebase for
>>>> qemu-xen-unstable is looking the same like for qemu-xen-3.4-testing and
>>>> the patch is applicable without any modifications it could be working
>>>> for xen-4.1 unstable as well, unfortunately I was not able to boot
>>>> PVOPS
>>>> kernel since it always ends up in kernel panic, maybe the missing
>>>> drivers or something like that.
>>>> 
>>> What kernel version? Did you use xen/stable-2.6.32.x branch from
>>> xen.git?
>> 
>> It's the one that's being automatically downloaded from git as
>> linux-2.6-pvops.git. The URL is
>> git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git with the
>> "fetch" being set to "+refs/heads/*:refs/remotes/xen/*". This is the
>> .git/config automatically created by `make world` in xen-unstable tree:
>> 
>> [core]
>> repositoryformatversion = 0
>> filemode = true
>> bare = false
>> logallrefupdates = true
>> [remote "xen"]
>> url = git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git
>> fetch = +refs/heads/*:refs/remotes/xen/*
>> [branch "xen/stable-2.6.31.x"]
>> remote = xen
>> merge = refs/heads/xen/stable-2.6.31.x
>> 
>> By default it's using uhci-hcd/ehci-hcd and ohci-hcd as builtins but I
>> needed to change it to be modules since otherwise it's being stuck.
>> I'm trying this on RHEL-5 dom0 (I'm having second partition RHEL-5
>> with upstream xen).
>>> See my example .config files from:
>>> http://wiki.xensource.com/xenwiki/XenParavirtOps in the
>>> "troubleshooting" section.
>> 
>> I'll have a look, thanks for the link.
>> 
>>> Works on F12/F13 dom0's.
>>> 
>>> For el5 dom0 you might need these:
>>> http://wiki.xensource.com/xenwiki/2.6.18-to-2.6.31-and-higher
>> 
>> Oh, ok, this may be very useful since I'm trying this on RHEL-5. Thanks!
>> 
>>> aka
>>> CONFIG_SYSFS_DEPRECATED=y
>>> CONFIG_SYSFS_DEPRECATED_V2=y
>>> 
>>> Also atm I think you need CONFIG_XEN_XENBUS_FRONTEND=y in the .config
>>> because of the recently added pv-on-hvm drivers (you'll get build
>>> failure without that option),
>>> so you need XEN_PCIDEV_FRONTEND XEN_BLKDEV_FRONTEND or
>>> XEN_NETDEV_FRONTEND or XEN_FBDEV_FRONTEND needs to be =y.
>>> 
>> 
>> Great! Thanks for your help Pasi! If anything I'll let you know.
>> 
>> Michal
>> 
>>> -- Pasi
>>> 
>>> 
>>>> On 06/03/2010 04:12 PM, Michal Novotny wrote:
>>>>> Oh, just one more thing that should be mentioned:
>>>>> 
>>>>> When you want to mount an image that is set as read-only in the domain
>>>>> configuration file but you omit to set mode to read-only it results
>>>>> into I/O errors when processing the requests. Remounting as read-only
>>>>> or unmounting and remounting using the `mount /dev/* /path/to/mount -o
>>>>> ro` shall do the mounting the correct way, i.e. with no I/O errors, so
>>>>> make sure you mount those disks as read-only otherwise you can be
>>>>> getting errors like:
>>>>> 
>>>>> end_request: I/O error, dev hdb, sector 52
>>>>> 
>>>>> Buffer I/O error on device hdb1, logical block 1
>>>>> 
>>>>> lost page write due to I/O error on hdb1
>>>>> 
>>>>> 
>>>>> and for IDE devices you'll be getting several additional DeviceFault
>>>>> errors since mounting the device read-write (default setting) writes
>>>>> some data onto a disk at the mount-time.
>>>>> 
>>>>> Michal
>>>>> 
>>>>> On 06/03/2010 04:04 PM, Michal Novotny wrote:
>>>>>> [Well, I did send an e-mail to the list using git but it's not here
>>>>>> so I'm forwarding the e-mail to the list for sure:]
>>>>>> 
>>>>>> Hi,
>>>>>> this is the patch for qemu-xen-3.4-testing to fix the read-only
>>>>>> image file handling since the image file was always treated as
>>>>>> read-write which means that all the HVM guests were able to
>>>>>> write to all the disk images available in domain configuration
>>>>>> file no matter what the mode of the image was defined. This
>>>>>> patch fixes this functionality to honor the O_RDONLY in the
>>>>>> BDRV_O_ACCESS flag in block.c and also fixes the IDE and SCSI
>>>>>> interfaces that uses it.
>>>>>> 
>>>>>> It's been tested on RHEL-5 with xen-3.4-testing version of
>>>>>> upstream xen with xen-3.4-testing qemu implementation.
>>>>>> 
>>>>>> For SCSI devices the DATA PROTECT request sense has been added
>>>>>> as found at: http://en.wikipedia.org/wiki/SCSI_Request_Sense_Command
>>>>>> 
>>>>>> file no matter what the mode of the image was defined. This
>>>>>> patch fixes this functionality to honor the O_RDONLY in the
>>>>>> BDRV_O_ACCESS flag in block.c and also fixes the IDE and SCSI
>>>>>> interfaces that uses it.
>>>>>> 
>>>>>> It's been tested on RHEL-5 with xen-3.4-testing version of
>>>>>> Michal
>>>>>> 
>>>>>> Signed-off-by: Michal Novotny<minovotn@xxxxxxxxxx>
>>>>>> 
>>>>>> 
>>>>>> _______________________________________________
>>>>>> Xen-devel mailing list
>>>>>> Xen-devel@xxxxxxxxxxxxxxxxxxx
>>>>>> http://lists.xensource.com/xen-devel
>>>>> 
>>>> 
>>>> -- 
>>>> Michal Novotny<minovotn@xxxxxxxxxx>, RHCE
>>>> Virtualization Team (xen userspace), Red Hat
>>>> 
>>>> 
>>>> _______________________________________________
>>>> Xen-devel mailing list
>>>> Xen-devel@xxxxxxxxxxxxxxxxxxx
>>>> http://lists.xensource.com/xen-devel
>> 
>> 
> 



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