Bug#660554: [3.1 -> 3.2.6 regression] [xen dom0] BUG at drivers/dma/ioat/dma_v2.c:163 at boot

[Jonathan Nieder <jrnieder@gmail.com>]

Hi Thomas,

Thomas Goirand wrote:

> When running kernel 3.2 with Xen 4.1 in SID, my development server just
> crashes at boot time.
[...]
> It took me quite some time to do (it really isn't trivial to setup, btw),
> but now I do have a serial console dump of the crash (see below).

Thanks.  Nice.

[...]
> kernel BUG at [...]/drivers/dma/ioat/dma_v2.c:163!M
[...]
> Pid: 0, comm: swapper/0 Not tainted 3.2.0-1-686-pae #1 Supermicro X8STi/X8STi
> EIP: 0061:[<f74df33d>] EFLAGS: 00010246 CPU: 0
> EIP is at __cleanup+0xd6/0x113 [ioatdma]

This is

	active = ioat2_ring_active(ioat);
	for (i = 0; i < active && !seen_current; i++) {
		...
		if (tx->phys == phys_complete)
			seen_current = true;
	}
	...
	BUG_ON(active && !seen_current); /* no active descs have written a completion? */

Can you reproduce it with the -amd64 kernel or with 3.3-rc4?

Curious,
Jonathan