Skip to contentSkip to conversation

ExpressCard hot-remove and hot-add not recognized by acpiphp

Bug 57961 Bjorn Helgaas 2 participants 6 messages Aug 23, 2013 3 messages not in the archive

Subsystems (2)
lore
Share & tools
lore

A message that is not in the archive (sent off-list or not yet received): [email protected]/

A message that is not in the archive (sent off-list or not yet received): [email protected]/

Bjorn Helgaas

author maintainer
#2 lore raw

[+cc linux-pci, linux-acpi, switch to email for now]

Quoted 4 lines · On Fri, Aug 23, 2013 at 7:34 AM, <[email protected]> wrote:

https://bugzilla.kernel.org/show_bug.cgi?id=57961
...
I'm arriving here from googling "_handle_hotplug_event_root Bus check notify on \_SB_.PCI0".

Huh, interesting. I didn't think the kernel bugzilla was visible to search engines (I wish it were). But maybe Google just found an email that mentioned the URL?

Quoted 2 lines

My Dell L421X is spitting this notification both when I close and open the laptop lid, one each. No ACPI LID event is emitted, which doesn't seem right.

Can you post a complete dmesg log including a lid close/event cycle?

Quoted 1 line

Running on 3.10.6. Is this bug related in any way?

Bug 57961 is for ExpressCard changes that we didn't handle correctly. It doesn't sound like you're adding or removing an ExpressCard, so you're likely seeing a different problem.

Is the problem that (1) you see "_handle_hotplug_event_root Bus check notify on \_SB_.PCI0" messages that you don't expect, and (2) you do not see LID events, which you do expect?

Is there anything that is not actually working correctly, or is it just messages that don't seem right?

Bjorn

#3 lore raw
Quoted 11 lines · Bjorn Helgaas

[+cc linux-pci, linux-acpi, switch to email for now]

Quoted 4 lines · On Fri, Aug 23, 2013 at 7:34 AM, <[email protected]> wrote:

https://bugzilla.kernel.org/show_bug.cgi?id=57961
...
I'm arriving here from googling "_handle_hotplug_event_root Bus check notify on \_SB_.PCI0".

Huh, interesting. I didn't think the kernel bugzilla was visible to search engines (I wish it were). But maybe Google just found an email that mentioned the URL?

Yes, I actually got there through LKML http://lkml.org/lkml/2013/5/10/432

Quoted 4 lines
Quoted 2 lines

My Dell L421X is spitting this notification both when I close and open the laptop lid, one each. No ACPI LID event is emitted, which doesn't seem right.

Can you post a complete dmesg log including a lid close/event cycle?

E-mailed that to you personally.

Quoted 6 lines
Quoted 1 line

Running on 3.10.6. Is this bug related in any way?

Bug 57961 is for ExpressCard changes that we didn't handle correctly. It doesn't sound like you're adding or removing an ExpressCard, so you're likely seeing a different problem.

Quoted 6 lines

Is the problem that (1) you see "_handle_hotplug_event_root Bus check notify on \_SB_.PCI0" messages that you don't expect, and (2) you do not see LID events, which you do expect?

Is there anything that is not actually working correctly, or is it just messages that don't seem right?

Mailing list thread discussed some apparently significant ACPI changes in 3.10. I've yet to have a laptop that didn't emit an ACPI LID event. Instead the kernel does emit something that looks like something is not quite what it should be. I'm wondering if I have missed something in kernel configuration or am I somehow affected by the recent ACPI changes or a machine specific bug somewhere. Dells are among the Linux-friendliest machines throughout history, that makes me think it could be the kernel.

You're right, I'm not on the acpiphp bus for sure, but sometimes things are related at a level above so I took a shot at trying to find out what's happening.

author maintainer
#4 lore raw
Quoted 48 lines · Leho Kraav
Quoted 12 lines · Bjorn Helgaas

[+cc linux-pci, linux-acpi, switch to email for now]

Quoted 6 lines · On Fri, Aug 23, 2013 at 7:34 AM, <[email protected]> wrote:

https://bugzilla.kernel.org/show_bug.cgi?id=57961
...
I'm arriving here from googling "_handle_hotplug_event_root Bus check notify on
\_SB_.PCI0".

Quoted 7 lines
Quoted 4 lines

My Dell L421X is spitting this notification both when I close and open the
laptop lid, one each. No ACPI LID event is emitted, which doesn't seem right.

Can you post a complete dmesg log including a lid close/event cycle?

E-mailed that to you personally.

Quoted 7 lines
Quoted 1 line

Running on 3.10.6. Is this bug related in any way?

Bug 57961 is for ExpressCard changes that we didn't handle correctly. It doesn't sound like you're adding or removing an ExpressCard, so you're likely seeing a different problem.

Quoted 6 lines

Is the problem that (1) you see "_handle_hotplug_event_root Bus check notify on \_SB_.PCI0" messages that you don't expect, and (2) you do not see LID events, which you do expect?

Is there anything that is not actually working correctly, or is it just messages that don't seem right?

Mailing list thread discussed some apparently significant ACPI changes in 3.10. I've yet to have a laptop that didn't emit an ACPI LID event. Instead the kernel does emit something that looks like something is not quite what it should be. I'm wondering if I have missed something in kernel configuration or am I somehow affected by the recent ACPI changes or a machine specific bug somewhere. Dells are among the Linux-friendliest machines throughout history, that makes me think it could be the kernel.

Quoted 3 lines

You're right, I'm not on the acpiphp bus for sure, but sometimes things are related at a level above so I took a shot at trying to find out what's happening.

I don't know anything about the LID notifications.

As far as the bus checks on \_SB_.PCI0, I think that message is new or possibly we register for those notifications on more devices that we previously did. If your laptop suspended when closing the lid, it doesn't surprise me that we get the Bus Check on resume, because that might be the only way we could discover device additions or removals that happened while suspended. I'm not sure why we would get them on suspend.

Regardless, we can't change the fact that the BIOS sends us those notification events. We could change or remove the message, but I suspect we might want to keep it for debugging purposes for a while, since we're actively working in that area.

Bjorn

#5 lore raw
Quoted 10 lines

I don't know anything about the LID notifications.

As far as the bus checks on \_SB_.PCI0, I think that message is new or possibly we register for those notifications on more devices that we previously did. If your laptop suspended when closing the lid, it doesn't surprise me that we get the Bus Check on resume, because that might be the only way we could discover device additions or removals that happened while suspended. I'm not sure why we would get them on suspend.

I don't suspend on lid close, actually. I close the lid just to carry the laptop around, and always suspend manually.

Thanks for taking a look. I guess the key takeaway here is that the notify message is harmless and I should look at somewhere else to figure out why I'm not getting a LID event.

author maintainer
#6 lore raw

[+cc Rafael]

Quoted 12 lines · Leho Kraav
Quoted 10 lines

I don't know anything about the LID notifications.

As far as the bus checks on \_SB_.PCI0, I think that message is new or possibly we register for those notifications on more devices that we previously did. If your laptop suspended when closing the lid, it doesn't surprise me that we get the Bus Check on resume, because that might be the only way we could discover device additions or removals that happened while suspended. I'm not sure why we would get them on suspend.

Quoted 6 lines

I don't suspend on lid close, actually. I close the lid just to carry the laptop around, and always suspend manually.

Thanks for taking a look. I guess the key takeaway here is that the notify message is harmless and I should look at somewhere else to figure out why I'm not getting a LID event.

Huh. That's strange. I don't know why you would get bus checks on lid open/close events when you're not suspending/resuming. Maybe Rafael will have some ideas.

If you can collect an acpidump, that might have a clue, too. At least, we ought to be able to see a method that is sending the Notify to the PCI host bridge.

Bjorn

A message that is not in the archive (sent off-list or not yet received): [email protected]

author maintainer
#8 lore raw
Quoted 14 lines · Leho Kraav
Quoted 13 lines · Bjorn Helgaas

[+cc Rafael]

Quoted 5 lines · Leho Kraav

I don't suspend on lid close, actually. I close the lid just to carry the laptop around, and always suspend manually.

Huh. That's strange. I don't know why you would get bus checks on lid open/close events when you're not suspending/resuming. Maybe Rafael will have some ideas.

Quoted 6 lines
Quoted 3 lines

If you can collect an acpidump, that might have a clue, too. At least, we ought to be able to see a method that is sending the Notify to the PCI host bridge.

acpidump attached

            Method (GNOT, 2, NotSerialized)
                         Notify (PCI0, Arg1)
                         Notify (GFX0, Arg1)

I wonder if this bus check on lid open/close has something to do with telling us that we should re-evaluate which monitors are present or useful. In any case, I think I'm out of my depth.