Re: MMIO ioremap() error with PCI passthrough

[Andy Burns <lists.xensource.com@adslpipe.co.uk>]

On 02/07/2008 13:54, Andy Burns wrote:

> All muxes tuned OK, and recording 3 concurrent programs from the single 
> tuner (which results in about 2Mbytes of data being read from the tuner 
> and written to disk) eats less than 10% CPU in domU and 0.5% in dom0, 
> about 130 interrupts/sec from the tuner.

After about an hour I got a kernel panic on the domU

Fatal DMA error! Please use 'swiotlb=force'
----------- [cut here ] --------- [please bite here ] ---------
Kernel BUG at arch/x86_64/kernel/../../i386/kernel/pci-dma-xen.c:165
invalid opcode: 0000 [1] SMP
last sysfs file: /block/dm-1/range
CPU 0
Modules linked in: xfs(U) saa7134_dvb(U) dvb_pll(U) mt352(U) 
video_buf_dvb(U) dvb_core(U) nxt200x(U) tda1004x(U) autofs4(U) sunrpc(U) 
xennet(U) ip6t_REJECT(U) xt_tcpudp(U) ip6table_filter(U) ip6_tables(U) 
x_tables(U) ipv6(U) xfrm_nalgo(U) crypto_api(U) dm_multipath(U) 
parport_pc(U) lp(U) parport(U) saa7134(U) video_buf(U) compat_ioctl32(U) 
ir_kbd_i2c(U) i2c_core(U) ir_common(U) videodev(U) pcspkr(U) 
v4l1_compat(U) v4l2_common(U) dm_snapshot(U) dm_zero(U) dm_mirror(U) 
dm_mod(U) xenblk(U) ext3(U) jbd(U) uhci_hcd(U) ohci_hcd(U) ehci_hcd(U)
Pid: 10678, comm: saa7130[0] dvb Tainted: G      2.6.18-prep #6
RIP: e030:[<ffffffff802720a2>]  [<ffffffff802720a2>] dma_map_sg+0x13f/0x1ae
RSP: e02b:ffff88002ea6be00  EFLAGS: 00010282
RAX: 000000000000002f RBX: ffff8800305c7df0 RCX: ffffffff804da728
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000003 R08: ffffffff804da728 R09: 0000000000001f5f
R10: 000000000000002c R11: ffff88002ea6c000 R12: 0000000000000006
R13: ffff88003fded070 R14: ffff88003df7ede8 R15: 0000000000000003
FS:  00002b787a63a560(0000) GS:ffffffff805ac000(0000) knlGS:0000000000000000
CS:  e033 DS: 0000 ES: 0000
Process saa7130[0] dvb (pid: 10678, threadinfo ffff88002ea6a000, task 
ffff880035e32860)
Stack:  ffff880035e6a0f0  ffff880035e6a0f0  ffff88003df7ede8 
ffff88003fded000
  0000000000000080  ffffffff88133937  ffff880035e6a0c0  0000000000005e00
  ffff88003df7e000  ffffffff88144cf0
Call Trace:
  [<ffffffff88133937>] :video_buf:videobuf_dma_map+0x115/0x159
  [<ffffffff88144cf0>] :saa7134:buffer_prepare+0xbb/0x19b
  [<ffffffff80298a84>] keventd_create_kthread+0x0/0xc4
  [<ffffffff88132d43>] :video_buf:videobuf_read_start+0xa8/0x139
  [<ffffffff882f034b>] :video_buf_dvb:videobuf_dvb_thread+0x2a/0x127
  [<ffffffff882f0321>] :video_buf_dvb:videobuf_dvb_thread+0x0/0x127
  [<ffffffff802339c8>] kthread+0xfe/0x132
  [<ffffffff80260b24>] child_rip+0xa/0x12
  [<ffffffff80298a84>] keventd_create_kthread+0x0/0xc4
  [<ffffffff802338ca>] kthread+0x0/0x132
  [<ffffffff80260b1a>] child_rip+0x0/0x12

Code: 0f 0b 68 a5 df 47 80 c2 a5 00 48 8b 7b f0 48 2b 3d 21 f1 40
RIP  [<ffffffff802720a2>] dma_map_sg+0x13f/0x1ae
  RSP <ffff88002ea6be00>
  <0>Kernel panic - not syncing: Fatal exception




I presume this kernel option *is* a domU option rather than dom0? when I 
  added it to grub, the domU crashes on boot ...

----------- [cut here ] --------- [please bite here ] ---------
Kernel BUG at lib/../arch/i386/kernel/swiotlb.c:160
invalid opcode: 0000 [1] SMP
last sysfs file:
CPU 0
Modules linked in:
Pid: 0, comm: swapper Not tainted 2.6.18-prep #6
RIP: e030:[<ffffffff8033ca50>]  [<ffffffff8033ca50>] 
swiotlb_init_with_default_size+0xa0/0x19e
RSP: e02b:ffffffff805edf40  EFLAGS: 00010282
RAX: 00000000fffffff4 RBX: 0000000000000900 RCX: 000000000021d106
RDX: ffffffffff578000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000004000000 R08: 0000000000001000 R09: ffffffff8064d9e0
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffffffff805ac000(0000) knlGS:0000000000000000
CS:  e033 DS: 0000 ES: 0000
Process swapper (pid: 0, threadinfo ffffffff805ec000, task ffffffff804d5a80)
Stack:  00000000000002c3  0000000002040800  0000000000000000 
ffffffff80276935
  0000000000000000  ffffffff8060051b  0000000000000000  0000000002040800
  0000000000000000  0000000000000000
Call Trace:
  [<ffffffff80276935>] pci_swiotlb_init+0x9/0x2d
  [<ffffffff8060051b>] mem_init+0x5e/0x233
  [<ffffffff805f6a73>] start_kernel+0x189/0x224
  [<ffffffff805f61e5>] _sinittext+0x1e5/0x1eb

Code: 0f 0b 68 26 d3 48 80 c2 a0 00 48 83 eb 80 48 8b 05 23 cf 34
RIP  [<ffffffff8033ca50>] swiotlb_init_with_default_size+0xa0/0x19e
  RSP <ffffffff805edf40>
  <0>Kernel panic - not syncing: Fatal exception