Xen project Mailing List

I will test another application.

2010/3/5 Pasi Kärkkäinen <pasik@xxxxxx>

On Fri, Mar 05, 2010 at 02:01:28PM -0300, Sergio Charpinel Jr. wrote:
> Hi,
> I created a PV guest, and did a passthrough on my PCI USB Controller, to
> use the webcam.
> But, I'm receiving a kernel panic message on my domU afte boot.
> I'm using CentOS 5.4 and Xen 3.4.2
> Password: Fatal DMA error! Please use 'swiotlb=force'

Did you try that 'swiotlb=force' option for the guest kernel?
Also, does the same problem happen if you run the official EL5 Xen (3.1.2)
instead of 3.4.2 ?

-- Pasi

> ----------- [cut here ] --------- [please bite here ] ---------
> Kernel BUG at arch/x86_64/kernel/../../i386/kernel/pci-dma-xen.c:394

> invalid opcode: 0000 [1] SMPÂ

> last sysfs file:
> /devices/xen/pci-0/pci0000:00/0000:00:00.3/usb1/1-1/1-1:1.0/usbdev1.2_ep82/dev

> CPU 0Â

> Modules linked in: autofs4 hidp rfcomm l2cap bluetooth lockd sunrpc
> ip_conntrack_netbios_ns ipt_MASQUERADE xt_mark iptable_nat ip_nat xt_MARK
> iptable_mangle ipt_REJECT xt_state ip_conntrack nfnetlink iptable_filter
> ip_tables ip6t_REJECT xt_tcpudp ip6table_filter ip6_tables x_tables ipv6
> xfrm_nalgo crypto_api dm_mirror dm_multipath scsi_dh scsi_mod parport_pc
> lp parport stv680 compat_ioctl32 videodev v4l1_compat pcspkr v4l2_common
> xennet dm_raid45 dm_message dm_region_hash dm_log dm_mod dm_mem_cache
> xenblk ext3 jbd uhci_hcd ohci_hcd ehci_hcd
> Pid: 1752, comm: zmc Not tainted 2.6.18-164.11.1.el5xen #1

> RIP: e030:[<ffffffff8027217b>] Â [<ffffffff8027217b>]

> dma_map_single+0x12d/0x17d

> RSP: e02b:ffff88000cfb1c78 Â EFLAGS: 00010282

> RAX: 000000000000002f RBX: ffff88000e860000 RCX: ffffffff804f3ba8
> RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
> RBP: 0000000035032000 R08: ffffffff804f3ba8 R09: 0000000000000000
> R10: 000000000000002d R11: ffff88001f4230c0 R12: 0000000000019610
> R13: ffff88001fdef870 R14: ffff88001fb5f980 R15: ffff880010296ad4

> FS: Â 00002b8745423c10(0000) GS:ffffffff805ca000(0000)
> knlGS:0000000000000000
> CS: Â e033 DS: 0000 ES: 0000

> Process zmc (pid: 1752, threadinfo ffff88000cfb0000, task
> ffff88000f4530c0)

> Stack: Â ffff88000f4530c0 Â ffff880010296ac0 Â 00000000ffffffff
> Â ffff880010296ac0Â
> Â ffff88001ff7d400 Â ffffffff803e4200 Â 0000000000000000
> Â 000000d0802572b0Â
> Â fffffffffff7ffff Â ffffffff802c2e18Â
> Call Trace:
> Â [<ffffffff803e4200>] hcd_submit_urb+0x693/0x748
> Â [<ffffffff802c2e18>] mod_zone_page_state+0x27/0x3d
> Â [<ffffffff8020b242>] kmem_cache_alloc+0x62/0x6d
> Â [<ffffffff8025e6e3>] cache_alloc_refill+0x13c/0x4e5
> Â [<ffffffff802cfc34>] __kmalloc+0x8f/0x9f
> Â [<ffffffff881377e0>] :stv680:stv680_start_stream+0x18b/0x1c5
> Â [<ffffffff881397a0>] :stv680:stv680_do_ioctl+0x4e1/0x57b
> Â [<ffffffff8811ddda>] :videodev:video_usercopy+0x1a1/0x265
> Â [<ffffffff881392bf>] :stv680:stv680_do_ioctl+0x0/0x57b
> Â [<ffffffff8031a360>] inode_has_perm+0x56/0x63
> Â [<ffffffff80222789>] __up_read+0x19/0x7f
> Â [<ffffffff802676cd>] do_page_fault+0xfae/0x12e0
> Â [<ffffffff8026ef47>] monotonic_clock+0x35/0x7b
> Â [<ffffffff80243f5c>] do_ioctl+0x55/0x6b
> Â [<ffffffff802316b5>] vfs_ioctl+0x457/0x4b9
> Â [<ffffffff8024e68e>] sys_ioctl+0x59/0x78
> Â [<ffffffff802602f9>] tracesys+0xab/0xb6
> Code: 0f 0b 68 3a 2b 49 80 c2 8a 01 4d 85 ed 74 11 49 8b 85 18 02Â
> RIP Â [<ffffffff8027217b>] dma_map_single+0x12d/0x17d
> Â RSP <ffff88000cfb1c78>
> Â <0>Kernel panic - not syncing: Fatal exception
> 2010/3/2 Jan Ä*eÅ¡Ä*ut <[1]Jan.Cescut@xxxxxx>

>
> Thanks for thorough explanation.
>
> Have a nice day,
> Jan
> -----Original Message-----

> From: Pasi KÃ€rkkÃ€inen [mailto:[2]pasik@xxxxxx]
> Sent: 27. februar 2010 14:04

> To: Jan Ä*eÅ¡Ä*ut
> Cc: [3]xen-users@xxxxxxxxxxxxxxxxxxx
> Subject: Re: [Xen-users] PCI Passthrough without VT-d
>

> On Fri, Feb 26, 2010 at 11:29:22PM +0100, Jan ?eÅ¡?ut wrote:
> > Â Â As I read XEN supports assigning a pci device to an unprivileged
> domain

> > Â Â without hardware supporting it. Has anyone already tried it? Are
> there any
> > Â Â security risks? If I understand correctly how PCI passthrough
> works the
> > Â Â performance should be the same as using the pci device in native
> mode. Is
> > Â Â it so? I have a PCI video card which would like to use inside a
> VM running
> > Â Â Windows XP.

> >
>
> Xen supports PCI passthrough to _PV_ (paravirtual) guests without VT-d,
> and has actually supported that for years. There are some potential
> security
> risks in this, since the PV guest gets full DMA control of the PCI
> device
> and could use it for malicious purposes.
>
> Xen PCI passthrough to HVM guests (=Windows) requires VT-d hardware
> support.
>
> Also, PCI passthrough of a VGA/video card is not as simple as PCI
> passthrough
> of other cards (nic, disk controller, usb controller).
>
> VGA has lots of legacy stuff related to it, some memory ranges, IO
> ports, VGA BIOS,
> etc that have to be 'passed through' aswell, and emulated.
>
> Xen 4.0.0 will have PCI passthrough support of primary VGA adapters, but
> it requires
> VT-d support as stated already earlier.
>
> -- Pasi
>
> ps. There is actually a hack/patch available that allows PCI passthrough
> to HVM guest
> without VT-d, but that only works for the _first_ started HVM guest, and
> it's experimental
> and not supported in any way. iirc the patch is available in xen-devel
> archives.
>
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>
> --
> Sergio Roberto Charpinel Jr.
>
> References
>
> Visible links
> 1. mailto:Jan.Cescut@xxxxxx
> 2. mailto:pasik@xxxxxx
> 3. mailto:xen-users@xxxxxxxxxxxxxxxxxxx
> 4. mailto:Xen-users@xxxxxxxxxxxxxxxxxxx
> 5. http://lists.xensource.com/xen-users

--
Sergio Roberto Charpinel Jr.