I'm getting this in my logs when starting up after going from a
2.6.20rc5 kernel (which didn't do this) to Linus' latest tree as of 36
hours ago:

Feb 18 14:52:32 localhost kernel: [   16.392136] Uniform
Multi-Platform E-IDE driver Revision: 7.00alpha2
Feb 18 14:52:32 localhost kernel: [   16.392210] ide: Assuming 33MHz
system bus speed for PIO modes; override with idebus=xx
Feb 18 14:52:32 localhost kernel: [   16.395039] Probing IDE interface ide0...
Feb 18 14:52:32 localhost kernel: [   16.780057] hda: ST315310A, ATA DISK drive
Feb 18 14:52:32 localhost kernel: [   17.391365] Probing IDE interface ide1...
Feb 18 14:52:32 localhost kernel: [   18.184752] hdc: LTN485, ATAPI
CD/DVD-ROM drive
Feb 18 14:52:32 localhost kernel: [   18.490570] ide0 at
0x1f0-0x1f7,0x3f6 on irq 14
Feb 18 14:52:32 localhost kernel: [   18.490978] ide1 at
0x170-0x177,0x376 on irq 15
Feb 18 14:52:32 localhost kernel: [   18.493214] hda: max request size: 128KiB
Feb 18 14:52:32 localhost kernel: [   18.493735] hda: 29336832 sectors
(15020 MB) w/2048KiB Cache, CHS=29104/16/63
Feb 18 14:52:32 localhost kernel: [   18.493899] hda: cache flushes
not supported
Feb 18 14:52:32 localhost kernel: [   18.494530]  hda: hda1 hda2 < hda5 >
Feb 18 14:52:32 localhost kernel: [   18.536466] ata_piix
0000:00:1f.1: version 2.00ac7
Feb 18 14:52:32 localhost kernel: [   18.536579] ata: 0x1F0 IDE port busy
Feb 18 14:52:32 localhost kernel: [   18.536583] ata: conflict with ide0
Feb 18 14:52:32 localhost kernel: [   18.536719] BUG: at
drivers/pci/pci.c:840 pcim_pin_device()
Feb 18 14:52:32 localhost kernel: [   18.536786]  [<c0104e91>]
show_trace_log_lvl+0x1a/0x2f
Feb 18 14:52:32 localhost kernel: [   18.536897]  [<c01054d1>]
show_trace+0x12/0x14
Feb 18 14:52:32 localhost kernel: [   18.536991]  [<c0105583>]
dump_stack+0x16/0x18
Feb 18 14:52:32 localhost kernel: [   18.537085]  [<c01d1c45>]
pcim_pin_device+0x40/0x4d
Feb 18 14:52:32 localhost kernel: [   18.537201]  [<c024822f>]
ata_pci_init_one+0x1ac/0x4bb
Feb 18 14:52:32 localhost kernel: [   18.537330]  [<c024ce7d>]
piix_init_one+0x418/0x435
Feb 18 14:52:32 localhost kernel: [   18.537431]  [<c01d424d>]
pci_device_probe+0x39/0x5b
Feb 18 14:52:32 localhost kernel: [   18.537528]  [<c021c82f>]
really_probe+0xbd/0x145
Feb 18 14:52:32 localhost kernel: [   18.537638]  [<c021c94c>]
driver_probe_device+0x95/0xa1
Feb 18 14:52:32 localhost kernel: [   18.537734]  [<c021ca61>]
__driver_attach+0x6a/0xa1
Feb 18 14:52:32 localhost kernel: [   18.537829]  [<c021be19>]
bus_for_each_dev+0x36/0x5b
Feb 18 14:52:32 localhost kernel: [   18.537925]  [<c021c6a3>]
driver_attach+0x19/0x1b
Feb 18 14:52:32 localhost kernel: [   18.538019]  [<c021c109>]
bus_add_driver+0x6a/0x170
Feb 18 14:52:32 localhost kernel: [   18.538114]  [<c021cc6c>]
driver_register+0x79/0x7e
Feb 18 14:52:32 localhost kernel: [   18.538209]  [<c01d43ca>]
__pci_register_driver+0x7b/0xa8
Feb 18 14:52:32 localhost kernel: [   18.538381]  [<c04280d6>]
piix_init+0x14/0x27
Feb 18 14:52:32 localhost kernel: [   18.538496]  [<c040f708>] init+0x95/0x17a
Feb 18 14:52:32 localhost kernel: [   18.538597]  [<c0104b13>]
kernel_thread_helper+0x7/0x10
Feb 18 14:52:32 localhost kernel: [   18.538693]  =======================
Feb 18 14:52:32 localhost kernel: [   18.538752] ata: 0x170 IDE port busy
Feb 18 14:52:32 localhost kernel: [   18.538756] ata: conflict with ide1
Feb 18 14:52:32 localhost kernel: [   18.538905] ata_piix: probe of
0000:00:1f.1 failed with error -16

Kernel is standard tree with no modifications.

Relevant code which triggers this from devices/pci/pci.c is:
void pcim_pin_device(struct pci_dev *pdev)
{
	struct pci_devres *dr;

	dr = find_pci_dr(pdev);
	WARN_ON(!dr || !dr->disable);
	if (dr)
		dr->disable = 0;
}

and it is the WARN_ON that is the line.

.config of kernel is attached.
output of lspci -vv is attached.

Can you please cc me on any discussions/requests as not subscribed to lkml.

NB Machine continues with boot and can run after this. Machine is a
little unstable though but could also be Broadcom 4306 issues as not
sure these drivers are yet stable on my machine...

Ian
-- 
Web: http://wand.net.nz/~iam4
Blog: http://iansblog.jandi.co.nz
WAND Network Research Group