|
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] Xen pci-passthrough problem with pci-detach and pci-assignable-remove
Wednesday, April 16, 2014, 5:30:57 PM, you wrote: > On Wed, Apr 02, 2014 at 12:43:12PM +0200, Sander Eikelenboom wrote: >> >> Tuesday, April 1, 2014, 6:13:09 PM, you wrote: >> >> > On Thu, Feb 20, 2014 at 05:18:46PM +0100, Sander Eikelenboom wrote: >> >> >> >> Thursday, February 20, 2014, 9:53:59 AM, you wrote: >> >> >> >> >> >> > Friday, January 24, 2014, 6:48:06 PM, you wrote: >> >> >> >> >> On Fri, Jan 24, 2014 at 02:36:02PM +0100, Sander Eikelenboom wrote: >> >> >>> >> >> >>> Friday, January 10, 2014, 6:38:10 PM, you wrote: >> >> >>> >> >> >>> >> > Wow. You just walked in a pile of bugs didn't you? And on Friday >> >> >>> >> > nonethless. >> >> >>> >> >> >> >>> >> As usual ;-) >> >> >>> >> >> >>> > Ha! >> >> >>> > ..snip.. >> >> >>> >> >> [ 489.082358] [<ffffffff81087ac6>] ? >> >> >>> >> >> mutex_spin_on_owner+0x38/0x45 >> >> >>> >> >> [ 489.106272] [<ffffffff818e5e22>] ? >> >> >>> >> >> schedule_preempt_disabled+0x6/0x9 >> >> >>> >> >> [ 489.130158] [<ffffffff818e7034>] ? >> >> >>> >> >> __mutex_lock_slowpath+0x159/0x1b5 >> >> >>> >> >> [ 489.154147] [<ffffffff818e70a6>] ? mutex_lock+0x16/0x25 >> >> >>> >> >> [ 489.177890] [<ffffffff8135972d>] ? >> >> >>> >> >> pci_reset_function+0x26/0x4e >> >> >>> >> >> >> >>> >> > Yeah, that bug my RFC patchset (the one that does the slot/bus >> >> >>> >> > reset) should also fix. >> >> >>> >> > I totally forgot about it ! >> >> >>> >> >> >> >>> >> Got a link to that patchset ? >> >> >>> >> >> >>> > https://lkml.org/lkml/2013/12/13/315 >> >> >>> >> >> >>> >> I at least could give it a spin .. you never know when fortune is >> >> >>> >> on your side :-) >> >> >>> >> >> >>> > It is also at this git tree: >> >> >>> >> >> >>> > git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git and the >> >> >>> > branch name is "devel/xen-pciback.slot_and_bus.v0". You will likely >> >> >>> > want to merge it in your current Linus tree. >> >> >>> >> >> >>> > Thank you! >> >> >>> >> >> >>> >> >> >>> Hi Konrad, >> >> >>> >> >> >>> Just got time to test this some more, when merging this branch >> >> >>> *except* the last commit (9599a5ad38a3bb250e996ccb2cdaab6fb68aaacd) >> >> >>> seems to help with my problem,i'm no capable of using: >> >> >>> - xl pci-detach >> >> >>> - xl pci-assignable-remove >> >> >>> - echo "BDF" > /sys/bus/pci/drivers/<devicename>/bind >> >> >>> >> >> >>> to remove a pci device from a running HVM guest and rebinding it to a >> >> >>> driver in dom0 without those nasty stacktraces :-) >> >> >>> So the first 4 seem to be an improvement. >> >> >>> >> >> >>> That last commit (9599a5ad38a3bb250e996ccb2cdaab6fb68aaacd) seems to >> >> >>> give troubles of it's own. >> >> >> >> >> Could you email me your lspci output and also which devices you >> >> >> move/switch etc? >> >> >> >> > Hi Konrad, >> >> >> >> > At the moment i found some time to figure out what goes wrong with the >> >> > xl pci-detach and xl pci-assignable-remove, i have been >> >> > able to narrow it down a bit: >> >> >> >> > The problem only occurs when you: >> >> > - passthrough 2 (or more?) pci devices assigned to a guest .. >> >> > - and only remove 1 of those devices with "xl pci-detach" followed by a >> >> > "xl pci-assignable-remove" >> >> > - when you first detach both devices with "xl pci-detach" before doing >> >> > the "xl pci-assignable-remove" it works ok. >> >> >> >> > In my case i'm passingthrough 2 devices (02:00.0 and 00:19.0) >> >> >> >> > I added some printk's and what i found out is that: >> >> > - after doing the pci-detach of 02:00.0, it doesn't call >> >> > pcistub_put_pci_dev for that device ... >> >> > - but when i subsequently pci-detach the second (and last) device >> >> > 00:19.0 .. it does call it for both 02:00.0 and 00:19.0 ... >> >> > - so somehow that call for the first detached device gets deferred .. >> >> > but since it are different devices and not functions of the same device >> >> > i don't >> >> > see any reason for it to wait until all other devices would have been >> >> > detached ... >> >> >> >> >> >> > I tried to capture the console output but some how that didn't work >> >> > out, so i attached a screenshot of what happens when: >> >> > - doing a xl pci-list for the guest >> >> > - doing a xl pci-assignable-list >> >> >> >> > - doing the xl pci-detach for 02:00.0 >> >> >> >> > - doing a xl pci-list for the guest >> >> > - doing a xl pci-assignable-list >> >> >> >> > - waiting some time ... >> >> >> >> > - doing the xl pci-detach for 00:19.0 >> >> >> >> > - doing a xl pci-list for the guest >> >> > - doing a xl pci-assignable-list >> >> >> >> > There you can see this strange sequence of events :-) >> >> >> >> > But i haven't been able to spot the culprit >> >> >> >> Enabled some extra debugging and added some more printk's .. (see new >> >> screenshot) >> >> >> >> From what it seems .. the frontend state for the first device isn't >> >> changed on the first pci-detach .. >> >> >> >> Is the signaling on pci-detach the guests (pcifront) responsibility or >> >> the toolstacks (libxl) ? >> >> > It usually is pcifront. And in the screenshot I see: >> > .. frontend is gone! unregister device >> > which should trigger the process. And it does look to do that. >> > Hm, I am wondering what the toolstack is waiting for. >> > Time to debug. >> >> Ok thx :-) > Just to make sure - you are not using the xen-pciback.hide parameter right? > Just doing the /sysfs dance of 'echo BDF'> to various places. I just took some dancing lessons .. and there is no difference by using xen-pciback.hide and doing the sysfs-dance before starting the domain. It still gives the warning about the device being pci-assignable-removed being "in use" .. and subsequent lock ups. (after the pci-detach followed by pci-assignable-remove of *not all* passed through devices. _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx http://lists.xen.org/xen-devel
|
 |
Lists.xenproject.org is hosted with RackSpace, monitoring our |