pcim_enable_device BUGs for libata devices in 2.6.20-git6

Robert Hancock
2007-02-12T00:44:51Z

I'm seeing BUGs like these on all libata-driven controllers when
suspending to disk on 2.6.20-git6:

sata_nv 0000:00:07.0: resuming
BUG: at drivers/pci/pci.c:817 pcim_enable_device()

Call Trace:
[<ffffffff80337d21>] pcim_enable_device+0x8a/0xa5
[<ffffffff88099d18>] :libata:ata_pci_device_do_resume+0x20/0x59
[<ffffffff880bb731>] :sata_nv:nv_pci_device_resume+0x1d/0x100
[<ffffffff8039d2bf>] resume_device+0xcb/0x12c
[<ffffffff8039d3ac>] dpm_resume+0x8c/0xec
[<ffffffff8039d456>] device_resume+0x4a/0x5d
[<ffffffff802a0a33>] pm_suspend_disk+0x160/0x170
[<ffffffff8029f4b6>] enter_state+0x52/0x1da
[<ffffffff8029f69c>] state_store+0x5e/0x79
[<ffffffff802f2b20>] sysfs_write_file+0xe4/0x118
[<ffffffff80214b58>] vfs_write+0xce/0x177
[<ffffffff8021553e>] sys_write+0x45/0x6e
[<ffffffff8025711e>] system_call+0x7e/0x83

It looks like what's happening is that during the "freezing" stage, we
suspend and then resume the controllers. ata_pci_device_do_suspend only
calls pci_disable_device if the event is PM_EVENT_SUSPEND but
ata_pci_device_do_resume calls pcim_enable_device unconditionally. If
the event was something else, then pcim_enable_device complains because
the device was previously enabled and never disabled.

Not sure what the best way to fix this is?

--
Robert Hancock Saskatoon, SK, Canada
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