Comment 1 for bug 1210470

I've a Mobility Radeon HD 5650 muxed with an intel card. If I boot with radeon.audio=1 and I switch the radeon card off when pulseaudio is running, then the kernel hangs as soon as I close X:

[ 489.177732] hda-intel 0000:01:00.1: Disabling via VGA-switcheroo
[ 489.297129] hda-intel 0000:01:00.1: Cannot lock devices!
[ 489.297139] radeon: switched off
[ 489.300356] [drm] Disabling audio support
[ 489.319552] radeon 0000:01:00.0: fence driver on ring 5 use gpu addr 0x000000000015e418 and cpu addr 0xffffc90009df0418
[ 489.973886] ACPI: \_SB_.PCI0: ACPI_NOTIFY_BUS_CHECK event: unsupported
[ 489.973903] _handle_hotplug_event_root: Bus check notify on \_SB_.PCI0
[ 678.992375] [drm:atom_op_jump] *ERROR* atombios stuck in loop for more than 5secs aborting
[ 678.992453] [drm:atom_execute_table_locked] *ERROR* atombios stuck executing CD0C (len 62, WS 0, PS 0) @ 0xCD28
[ 683.996303] [drm:atom_op_jump] *ERROR* atombios stuck in loop for more than 5secs aborting
[ 683.996377] [drm:atom_execute_table_locked] *ERROR* atombios stuck executing CD0C (len 62, WS 0, PS 0) @ 0xCD28
[ 683.996453] [drm:atom_execute_table_locked] *ERROR* atombios stuck executing C3DC (len 871, WS 0, PS 0) @ 0xC439
[ 689.000275] [drm:atom_op_jump] *ERROR* atombios stuck in loop for more than 5secs aborting
[ 689.000349] [drm:atom_execute_table_locked] *ERROR* atombios stuck executing CD0C (len 62, WS 0, PS 0) @ 0xCD28
[ 694.004285] [drm:atom_op_jump] *ERROR* atombios stuck in loop for more than 5secs aborting
[ 694.004363] [drm:atom_execute_table_locked] *ERROR* atombios stuck executing CD0C (len 62, WS 0, PS 0) @ 0xCD28
[ 699.008330] [drm:atom_op_jump] *ERROR* atombios stuck in loop for more than 5secs aborting
[ 699.008414] [drm:atom_execute_table_locked] *ERROR* atombios stuck executing CD0C (len 62, WS 0, PS 0) @ 0xCD28
[ 699.514458] init: tty1 main process (2460) killed by QUIT signal
[ 699.514489] init: tty1 main process ended, respawning
[ 704.012405] [drm:atom_op_jump] *ERROR* atombios stuck in loop for more than 5secs aborting
[ 704.012492] [drm:atom_execute_table_locked] *ERROR* atombios stuck executing CD0C (len 62, WS 0, PS 0) @ 0xCD28
[ 709.016515] [drm:atom_op_jump] *ERROR* atombios stuck in loop for more than 5secs aborting
[ 709.016596] [drm:atom_execute_table_locked] *ERROR* atombios stuck executing CD0C (len 62, WS 0, PS 0) @ 0xCD28

These errors doesn't happen instead if I close X and kill pulseaudio before switching cards.

Not sure if this is a pulseaudio issue or a kernel one (that should notify pulseaudio about the unplugged HDMI audio card).