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[TJ <567696@xxxxxxxxxxxxxxxxxx>]

I've managed to trigger the fault using kernel v2.6.38 from Natty whilst
running the Software Sources update after enabling additional
repositories.

I noticed in previous debugging sessions that the DRM_DEBUG messages
emitted when enabled in the kernel with

echo 1 | sudo tee /sys/module/drm/parameters/debug

Shows hundreds of calls to radeon_freelist_get() and additionally the
reported done_age doesn't increment. E.g:

Jul 18 17:30:55 A7M266D kernel: [27706.636121] [drm:drm_ioctl], pid=923, cmd=0xc0286429, nr=0x29, dev 0xe200, auth=1
Jul 18 17:30:55 A7M266D kernel: [27706.636142] [drm:radeon_freelist_get], done_age = 628
Jul 18 17:30:55 A7M266D kernel: [27706.636153] [drm:radeon_freelist_get], done_age = 628
Jul 18 17:30:55 A7M266D kernel: [27706.636158] [drm:radeon_freelist_get], done_age = 628
Jul 18 17:30:55 A7M266D kernel: [27706.636163] [drm:radeon_freelist_get], done_age = 628
Jul 18 17:30:55 A7M266D kernel: [27706.636168] [drm:radeon_freelist_get], done_age = 628
Jul 18 17:30:55 A7M266D kernel: [27706.636173] [drm:radeon_freelist_get], done_age = 628
Jul 18 17:30:55 A7M266D kernel: [27706.636178] [drm:radeon_freelist_get], done_age = 628
Jul 18 17:30:55 A7M266D kernel: [27706.636184] [drm:radeon_freelist_get], done_age = 628
Jul 18 17:30:55 A7M266D kernel: [27706.636189] [drm:radeon_freelist_get], done_age = 628
Jul 18 17:30:55 A7M266D kernel: [27706.636194] [drm:radeon_freelist_get], done_age = 628

My initial analysis makes me think that there's a logic bug in
radeon_cp_get_buffers() that causes it to get stuck in the loop:

	for (i = d->granted_count; i < d->request_count; i++) {
		buf = radeon_freelist_get(dev);
		...
 		d->granted_count++;
	}
	return 0;

I shall be working to obtain more specific details that can lead to an
explanation and fix for this.

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https://bugs.launchpad.net/bugs/567696

Title:
  [mi] EQ overflowing. The server is probably stuck in an infinite loop

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