Linux domU only works with xen_platform_pci=0 ?

[Nathan Friess]

On 2018-05-22 03:01 AM, Roger Pau Monné wrote:
> On Mon, May 21, 2018 at 01:51:13PM -0600, Nathan Friess wrote:
>> On 2018-05-19 02:02 AM, Roger Pau Monné wrote:
>> On a related note, did these patches ever make it into 11-stable?  I don't
>> see them at svn.freebsd.org/base/stable/11 but I may have missed something.
>>
>> https://lists.freebsd.org/pipermail/freebsd-xen/2016-December/002918.html
> 
> I don't think they are on HEAD either?
> 
> I don't have a lot of time ATM, so if you want to pick the patches,
> rebase them onto HEAD, test them and give me a branch I'm more than
> happy to review and commit them.
> 

Attached are 4 patches from your git repository, applied to HEAD with 
some testing on an up-to-date 12-CURRENT install.  I did see one kernel 
message that I assume is not fatal (more on that later).  I'm not able 
to test running as dom0 right now because I don't have any newish 
hardware available.  My main use case is FreeBSD as domU serving disks 
to other domUs.

The 0001-0003 patches applied cleanly to HEAD.  0004 required moving a 
function around to fix a compile error but otherwise is unchanged.  I 
also copied your commit messages from git into the patches for reference.


I was going to attach a patch to fix xen-tools with iasl in 12-CURRENT, 
but as I type this I see that you just committed a fix yesterday. 
Thanks! :)


The kernel message that I'm seeing appears when a domU shuts down or a 
disk is detached from a running domU, while the backend for the disk is 
my 12-CURRENT test system.  The backend spits this out:


lock order reversal: (sleepable after non-sleepable)
  1st 0xfffff8000802fe90 xbbd1 (xbbd1) @ 
/usr/src/sys/dev/xen/blkback/blkback.c:3423
  2nd 0xffffffff81fdf890 intrsrc (intrsrc) @ 
/usr/src/sys/x86/x86/intr_machdep.c:224
stack backtrace:
#0 0xffffffff80bdd993 at witness_debugger+0x73
#1 0xffffffff80bdd814 at witness_checkorder+0xe34
#2 0xffffffff80b7d798 at _sx_xlock+0x68
#3 0xffffffff811b3913 at intr_remove_handler+0x43
#4 0xffffffff811c63ef at xen_intr_unbind+0x10f
#5 0xffffffff80a12ecf at xbb_disconnect+0x2f
#6 0xffffffff80a12e54 at xbb_shutdown+0x1e4
#7 0xffffffff80a10be4 at xbb_frontend_changed+0x54
#8 0xffffffff80ed66a4 at xenbusb_back_otherend_changed+0x14
#9 0xffffffff80a2a382 at xenwatch_thread+0x182
#10 0xffffffff80b34164 at fork_exit+0x84
#11 0xffffffff8101ec9e at fork_trampoline+0xe
lock order reversal: (sleepable after non-sleepable)
  1st 0xfffff80008030690 xbbd0 (xbbd0) @ 
/usr/src/sys/dev/xen/blkback/blkback.c:3423
  2nd 0xffffffff81fdf890 intrsrc (intrsrc) @ 
/usr/src/sys/x86/x86/intr_machdep.c:224
stack backtrace:
#0 0xffffffff80bdd993 at witness_debugger+0x73
#1 0xffffffff80bdd814 at witness_checkorder+0xe34
#2 0xffffffff80b7d798 at _sx_xlock+0x68
#3 0xffffffff811b3913 at intr_remove_handler+0x43
#4 0xffffffff811c63ef at xen_intr_unbind+0x10f
#5 0xffffffff80a12ecf at xbb_disconnect+0x2f
#6 0xffffffff80a12e54 at xbb_shutdown+0x1e4
#7 0xffffffff80a10be4 at xbb_frontend_changed+0x54
#8 0xffffffff80ed66a4 at xenbusb_back_otherend_changed+0x14
#9 0xffffffff80a2a382 at xenwatch_thread+0x182
#10 0xffffffff80b34164 at fork_exit+0x84
#11 0xffffffff8101ec9e at fork_trampoline+0xe


Otherwise disk backends seem to work fine.

Nathan
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-xenstore-remove-the-suspend-sx-lock.patch
Type: text/x-patch
Size: 6206 bytes
Desc: not available
URL: <http://lists.freebsd.org/pipermail/freebsd-xen/attachments/20180523/66edd932/attachment.bin>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0002-xenstore-don-t-wait-with-the-PCATCH-flag.patch
Type: text/x-patch
Size: 1367 bytes
Desc: not available
URL: <http://lists.freebsd.org/pipermail/freebsd-xen/attachments/20180523/66edd932/attachment-0001.bin>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0003-dev-xenstore-add-support-for-watches.patch
Type: text/x-patch
Size: 9285 bytes
Desc: not available
URL: <http://lists.freebsd.org/pipermail/freebsd-xen/attachments/20180523/66edd932/attachment-0002.bin>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0004-xenstore-dev-prevent-user-space-xenstore-device-from.patch
Type: text/x-patch
Size: 2393 bytes
Desc: not available
URL: <http://lists.freebsd.org/pipermail/freebsd-xen/attachments/20180523/66edd932/attachment-0003.bin>