| Message ID | CAOLK0pySsrXEjbLor0v3zhbtUGx_437d0r5WAxWnufzZ+QwpCQ@mail.gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Thursday, September 05, 2013 02:17:06 PM Lan Tianyu wrote: > 2013/9/5 Alex Williamson <alex.williamson@redhat.com>: > > On Thu, 2013-09-05 at 01:35 +0200, Rafael J. Wysocki wrote: > >> On Wednesday, September 04, 2013 05:12:14 PM Alex Williamson wrote: > >> > On Thu, 2013-09-05 at 00:54 +0200, Rafael J. Wysocki wrote: > >> > > On Wednesday, September 04, 2013 02:36:34 PM Alex Williamson wrote: > >> > > > On Thu, 2013-07-18 at 01:32 +0200, Rafael J. Wysocki wrote: > >> > > > > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > >> > > > > > >> > > > > The current implementation of acpiphp_check_bridge() is pretty dumb: > >> > > > > - It enables a slot if it's not enabled and the slot status is > >> > > > > ACPI_STA_ALL. > >> > > > > - It disables a slot if it's enabled and the slot status is not > >> > > > > ACPI_STA_ALL. > >> > > > > > >> > > > > This behavior is not sufficient to handle the Thunderbolt daisy > >> > > > > chaining case properly, however, because in that case the bus > >> > > > > behind the already enabled slot needs to be rescanned for new > >> > > > > devices. > >> > > > > > >> > > > > For this reason, modify acpiphp_check_bridge() so that slots are > >> > > > > disabled and stopped if they are not in the ACPI_STA_ALL state. > >> > > > > > >> > > > > For slots in the ACPI_STA_ALL state, devices behind them that don't > >> > > > > respond are trimmed using a new function, trim_stale_devices(), > >> > > > > introduced specifically for this purpose. That function walks > >> > > > > the given bus and checks each device on it. If the device doesn't > >> > > > > respond, it is assumed to be gone and is removed. > >> > > > > > >> > > > > Once all of the stale devices directy behind the slot have been > >> > > > > removed, acpiphp_check_bridge() will start looking for new devices > >> > > > > that might have appeared on the given bus. It will do that even if > >> > > > > the slot is already enabled (SLOT_ENABLED is set for it). > >> > > > > > >> > > > > In addition to that, make the bus check notification ignore > >> > > > > SLOT_ENABLED and go for enable_device() directly if bridge is NULL, > >> > > > > so that devices behind the slot are re-enumerated in that case too. > >> > > > > > >> > > > > This change is based on earlier patches from Kirill A Shutemov > >> > > > > and Mika Westerberg. > >> > > > > > >> > > > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > >> > > > > Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> > >> > > > > --- > >> > > > > >> > > > FYI, git bisect landed on this patch as the cause of my serial console > >> > > > dying on current upstream. Further debugging to come... Thanks, > >> > > > >> > > Well, sorry about that. > >> > > > >> > > What exactly do you mean by "dying"? > >> > > >> > Sorry, I was hoping to have more details quickly, but it's been a pain > >> > to debug. By dying I mean serial console output suddenly stops during > >> > kernel boot and nothing more comes out of it until after the system is > >> > rebooted. The problem happens when acpiphp_check_bridge() calls > >> > enable_slot(). The serial console dies somewhere down in > >> > acpiphp_bus_trim(). I think this is happening on the 00:1f ISA bridge, > >> > so there's a good chance the serial ports are described as somewhere > >> > under there. > >> > >> Can you please check if that is the acpiphp_bus_trim() called by > >> acpiphp_bus_add() or the other one called from trim_stale_devices()? > >> > >> Just add a dump_stack() or WARN_ON(1) to trim_stale_devices() next to > >> the acpiphp_bus_trim() call and see if that triggers. I *think* it's the one > >> in acpiphp_bus_add(), but it won't hurt to verify that. > > > > Here's the call path: > > > > [ 16.120824] [<ffffffff81627e6c>] dump_stack+0x55/0x76 > > [ 16.125979] [<ffffffff8162132e>] enable_slot+0x4ee/0x5e0 > > [ 16.131396] [<ffffffff813418fb>] ? trim_stale_devices+0x5b/0xf0 > > [ 16.137420] [<ffffffff81341b35>] acpiphp_check_bridge+0xd5/0x110 > > [ 16.143531] [<ffffffff81342acb>] hotplug_event+0x16b/0x260 > > [ 16.149115] [<ffffffff81072cd9>] ? process_one_work+0x189/0x540 > > [ 16.155136] [<ffffffff81342bf0>] hotplug_event_work+0x30/0x70 > > [ 16.160978] [<ffffffff81072d3b>] process_one_work+0x1eb/0x540 > > [ 16.166819] [<ffffffff81072cd9>] ? process_one_work+0x189/0x540 > > [ 16.172836] [<ffffffff8107353c>] worker_thread+0x11c/0x370 > > [ 16.178426] [<ffffffff81073420>] ? rescuer_thread+0x350/0x350 > > [ 16.184276] [<ffffffff8107b0ea>] kthread+0xea/0xf0 > > [ 16.189165] [<ffffffff8107b000>] ? kthread_create_on_node+0x160/0x160 > > [ 16.195700] [<ffffffff816395dc>] ret_from_fork+0x7c/0xb0 > > [ 16.201109] [<ffffffff8107b000>] ? kthread_create_on_node+0x160/0x160 > > > > The actual death of the serial console occurs in acpi_device_set_power() > > called from: > > > > enable_slot() > > acpiphp_bus_add() > > acpiphp_bus_trim() > > acpi_bus_trim() > > acpi_walk_namespace() > > acpi_bus_remove() > > acpi_device_unregister() > > acpi_device_set_power() > > > > I can't seem to get a path from the acpi devices in question there, so I > > have no idea what's getting trimmed here. It worries me quite a bit by > > introducing this trimming that apparently wasn't happening before > > though. Thanks, > > Hi Alex: > Could you apply the following patch and bootup with kernel param > "acpiphp.acpiphp_debug=1"? > I guess the patch can make serial port alive. It will not > be put into D3cold > during trimming. But I don't know why it doesn't work after being put > back to D0. Do we actually put it into D0 in acpi_bus_scan()? I don't think so. > So please attach output of acpidump and the dmesg if it can work. Thanks. > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index e763651..359b23d 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -1110,7 +1110,7 @@ static void acpi_device_unregister(struct > acpi_device *device) > * power resources the device depends on and turn off the ones that have > * no more references. > */ > - acpi_device_set_power(device, ACPI_STATE_D3_COLD); > + //acpi_device_set_power(device, ACPI_STATE_D3_COLD); > device->handle = NULL; > put_device(&device->dev); > } I don't think we should do the trimming in acpiphp_bus_add() at all. Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
2013/9/5 Rafael J. Wysocki <rjw@sisk.pl>: > On Thursday, September 05, 2013 02:17:06 PM Lan Tianyu wrote: >> 2013/9/5 Alex Williamson <alex.williamson@redhat.com>: >> > On Thu, 2013-09-05 at 01:35 +0200, Rafael J. Wysocki wrote: >> >> On Wednesday, September 04, 2013 05:12:14 PM Alex Williamson wrote: >> >> > On Thu, 2013-09-05 at 00:54 +0200, Rafael J. Wysocki wrote: >> >> > > On Wednesday, September 04, 2013 02:36:34 PM Alex Williamson wrote: >> >> > > > On Thu, 2013-07-18 at 01:32 +0200, Rafael J. Wysocki wrote: >> >> > > > > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >> >> > > > > >> >> > > > > The current implementation of acpiphp_check_bridge() is pretty dumb: >> >> > > > > - It enables a slot if it's not enabled and the slot status is >> >> > > > > ACPI_STA_ALL. >> >> > > > > - It disables a slot if it's enabled and the slot status is not >> >> > > > > ACPI_STA_ALL. >> >> > > > > >> >> > > > > This behavior is not sufficient to handle the Thunderbolt daisy >> >> > > > > chaining case properly, however, because in that case the bus >> >> > > > > behind the already enabled slot needs to be rescanned for new >> >> > > > > devices. >> >> > > > > >> >> > > > > For this reason, modify acpiphp_check_bridge() so that slots are >> >> > > > > disabled and stopped if they are not in the ACPI_STA_ALL state. >> >> > > > > >> >> > > > > For slots in the ACPI_STA_ALL state, devices behind them that don't >> >> > > > > respond are trimmed using a new function, trim_stale_devices(), >> >> > > > > introduced specifically for this purpose. That function walks >> >> > > > > the given bus and checks each device on it. If the device doesn't >> >> > > > > respond, it is assumed to be gone and is removed. >> >> > > > > >> >> > > > > Once all of the stale devices directy behind the slot have been >> >> > > > > removed, acpiphp_check_bridge() will start looking for new devices >> >> > > > > that might have appeared on the given bus. It will do that even if >> >> > > > > the slot is already enabled (SLOT_ENABLED is set for it). >> >> > > > > >> >> > > > > In addition to that, make the bus check notification ignore >> >> > > > > SLOT_ENABLED and go for enable_device() directly if bridge is NULL, >> >> > > > > so that devices behind the slot are re-enumerated in that case too. >> >> > > > > >> >> > > > > This change is based on earlier patches from Kirill A Shutemov >> >> > > > > and Mika Westerberg. >> >> > > > > >> >> > > > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >> >> > > > > Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> >> >> > > > > --- >> >> > > > >> >> > > > FYI, git bisect landed on this patch as the cause of my serial console >> >> > > > dying on current upstream. Further debugging to come... Thanks, >> >> > > >> >> > > Well, sorry about that. >> >> > > >> >> > > What exactly do you mean by "dying"? >> >> > >> >> > Sorry, I was hoping to have more details quickly, but it's been a pain >> >> > to debug. By dying I mean serial console output suddenly stops during >> >> > kernel boot and nothing more comes out of it until after the system is >> >> > rebooted. The problem happens when acpiphp_check_bridge() calls >> >> > enable_slot(). The serial console dies somewhere down in >> >> > acpiphp_bus_trim(). I think this is happening on the 00:1f ISA bridge, >> >> > so there's a good chance the serial ports are described as somewhere >> >> > under there. >> >> >> >> Can you please check if that is the acpiphp_bus_trim() called by >> >> acpiphp_bus_add() or the other one called from trim_stale_devices()? >> >> >> >> Just add a dump_stack() or WARN_ON(1) to trim_stale_devices() next to >> >> the acpiphp_bus_trim() call and see if that triggers. I *think* it's the one >> >> in acpiphp_bus_add(), but it won't hurt to verify that. >> > >> > Here's the call path: >> > >> > [ 16.120824] [<ffffffff81627e6c>] dump_stack+0x55/0x76 >> > [ 16.125979] [<ffffffff8162132e>] enable_slot+0x4ee/0x5e0 >> > [ 16.131396] [<ffffffff813418fb>] ? trim_stale_devices+0x5b/0xf0 >> > [ 16.137420] [<ffffffff81341b35>] acpiphp_check_bridge+0xd5/0x110 >> > [ 16.143531] [<ffffffff81342acb>] hotplug_event+0x16b/0x260 >> > [ 16.149115] [<ffffffff81072cd9>] ? process_one_work+0x189/0x540 >> > [ 16.155136] [<ffffffff81342bf0>] hotplug_event_work+0x30/0x70 >> > [ 16.160978] [<ffffffff81072d3b>] process_one_work+0x1eb/0x540 >> > [ 16.166819] [<ffffffff81072cd9>] ? process_one_work+0x189/0x540 >> > [ 16.172836] [<ffffffff8107353c>] worker_thread+0x11c/0x370 >> > [ 16.178426] [<ffffffff81073420>] ? rescuer_thread+0x350/0x350 >> > [ 16.184276] [<ffffffff8107b0ea>] kthread+0xea/0xf0 >> > [ 16.189165] [<ffffffff8107b000>] ? kthread_create_on_node+0x160/0x160 >> > [ 16.195700] [<ffffffff816395dc>] ret_from_fork+0x7c/0xb0 >> > [ 16.201109] [<ffffffff8107b000>] ? kthread_create_on_node+0x160/0x160 >> > >> > The actual death of the serial console occurs in acpi_device_set_power() >> > called from: >> > >> > enable_slot() >> > acpiphp_bus_add() >> > acpiphp_bus_trim() >> > acpi_bus_trim() >> > acpi_walk_namespace() >> > acpi_bus_remove() >> > acpi_device_unregister() >> > acpi_device_set_power() >> > >> > I can't seem to get a path from the acpi devices in question there, so I >> > have no idea what's getting trimmed here. It worries me quite a bit by >> > introducing this trimming that apparently wasn't happening before >> > though. Thanks, >> >> Hi Alex: >> Could you apply the following patch and bootup with kernel param >> "acpiphp.acpiphp_debug=1"? >> I guess the patch can make serial port alive. It will not >> be put into D3cold >> during trimming. But I don't know why it doesn't work after being put >> back to D0. > > Do we actually put it into D0 in acpi_bus_scan()? I don't think so. > Hi Rafael: I mean the code in the acpiphp_bus_add(). After trimming and acpi bus scan handle, the device will be put back to D0 if acpi_bus_get_device() return acpi device. So I thought the serial port is put back to D0. >> So please attach output of acpidump and the dmesg if it can work. Thanks. >> >> diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c >> index e763651..359b23d 100644 >> --- a/drivers/acpi/scan.c >> +++ b/drivers/acpi/scan.c >> @@ -1110,7 +1110,7 @@ static void acpi_device_unregister(struct >> acpi_device *device) >> * power resources the device depends on and turn off the ones that have >> * no more references. >> */ >> - acpi_device_set_power(device, ACPI_STATE_D3_COLD); >> + //acpi_device_set_power(device, ACPI_STATE_D3_COLD); >> device->handle = NULL; >> put_device(&device->dev); >> } > > I don't think we should do the trimming in acpiphp_bus_add() at all. Yes, I agree. > > Thanks, > Rafael >
On Thursday, September 05, 2013 09:11:51 AM Lan Tianyu wrote: > 2013/9/5 Rafael J. Wysocki <rjw@sisk.pl>: > > On Thursday, September 05, 2013 02:17:06 PM Lan Tianyu wrote: > >> 2013/9/5 Alex Williamson <alex.williamson@redhat.com>: > >> > On Thu, 2013-09-05 at 01:35 +0200, Rafael J. Wysocki wrote: > >> >> On Wednesday, September 04, 2013 05:12:14 PM Alex Williamson wrote: > >> >> > On Thu, 2013-09-05 at 00:54 +0200, Rafael J. Wysocki wrote: > >> >> > > On Wednesday, September 04, 2013 02:36:34 PM Alex Williamson wrote: > >> >> > > > On Thu, 2013-07-18 at 01:32 +0200, Rafael J. Wysocki wrote: > >> >> > > > > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > >> >> > > > > > >> >> > > > > The current implementation of acpiphp_check_bridge() is pretty dumb: > >> >> > > > > - It enables a slot if it's not enabled and the slot status is > >> >> > > > > ACPI_STA_ALL. > >> >> > > > > - It disables a slot if it's enabled and the slot status is not > >> >> > > > > ACPI_STA_ALL. > >> >> > > > > > >> >> > > > > This behavior is not sufficient to handle the Thunderbolt daisy > >> >> > > > > chaining case properly, however, because in that case the bus > >> >> > > > > behind the already enabled slot needs to be rescanned for new > >> >> > > > > devices. > >> >> > > > > > >> >> > > > > For this reason, modify acpiphp_check_bridge() so that slots are > >> >> > > > > disabled and stopped if they are not in the ACPI_STA_ALL state. > >> >> > > > > > >> >> > > > > For slots in the ACPI_STA_ALL state, devices behind them that don't > >> >> > > > > respond are trimmed using a new function, trim_stale_devices(), > >> >> > > > > introduced specifically for this purpose. That function walks > >> >> > > > > the given bus and checks each device on it. If the device doesn't > >> >> > > > > respond, it is assumed to be gone and is removed. > >> >> > > > > > >> >> > > > > Once all of the stale devices directy behind the slot have been > >> >> > > > > removed, acpiphp_check_bridge() will start looking for new devices > >> >> > > > > that might have appeared on the given bus. It will do that even if > >> >> > > > > the slot is already enabled (SLOT_ENABLED is set for it). > >> >> > > > > > >> >> > > > > In addition to that, make the bus check notification ignore > >> >> > > > > SLOT_ENABLED and go for enable_device() directly if bridge is NULL, > >> >> > > > > so that devices behind the slot are re-enumerated in that case too. > >> >> > > > > > >> >> > > > > This change is based on earlier patches from Kirill A Shutemov > >> >> > > > > and Mika Westerberg. > >> >> > > > > > >> >> > > > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > >> >> > > > > Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> > >> >> > > > > --- > >> >> > > > > >> >> > > > FYI, git bisect landed on this patch as the cause of my serial console > >> >> > > > dying on current upstream. Further debugging to come... Thanks, > >> >> > > > >> >> > > Well, sorry about that. > >> >> > > > >> >> > > What exactly do you mean by "dying"? > >> >> > > >> >> > Sorry, I was hoping to have more details quickly, but it's been a pain > >> >> > to debug. By dying I mean serial console output suddenly stops during > >> >> > kernel boot and nothing more comes out of it until after the system is > >> >> > rebooted. The problem happens when acpiphp_check_bridge() calls > >> >> > enable_slot(). The serial console dies somewhere down in > >> >> > acpiphp_bus_trim(). I think this is happening on the 00:1f ISA bridge, > >> >> > so there's a good chance the serial ports are described as somewhere > >> >> > under there. > >> >> > >> >> Can you please check if that is the acpiphp_bus_trim() called by > >> >> acpiphp_bus_add() or the other one called from trim_stale_devices()? > >> >> > >> >> Just add a dump_stack() or WARN_ON(1) to trim_stale_devices() next to > >> >> the acpiphp_bus_trim() call and see if that triggers. I *think* it's the one > >> >> in acpiphp_bus_add(), but it won't hurt to verify that. > >> > > >> > Here's the call path: > >> > > >> > [ 16.120824] [<ffffffff81627e6c>] dump_stack+0x55/0x76 > >> > [ 16.125979] [<ffffffff8162132e>] enable_slot+0x4ee/0x5e0 > >> > [ 16.131396] [<ffffffff813418fb>] ? trim_stale_devices+0x5b/0xf0 > >> > [ 16.137420] [<ffffffff81341b35>] acpiphp_check_bridge+0xd5/0x110 > >> > [ 16.143531] [<ffffffff81342acb>] hotplug_event+0x16b/0x260 > >> > [ 16.149115] [<ffffffff81072cd9>] ? process_one_work+0x189/0x540 > >> > [ 16.155136] [<ffffffff81342bf0>] hotplug_event_work+0x30/0x70 > >> > [ 16.160978] [<ffffffff81072d3b>] process_one_work+0x1eb/0x540 > >> > [ 16.166819] [<ffffffff81072cd9>] ? process_one_work+0x189/0x540 > >> > [ 16.172836] [<ffffffff8107353c>] worker_thread+0x11c/0x370 > >> > [ 16.178426] [<ffffffff81073420>] ? rescuer_thread+0x350/0x350 > >> > [ 16.184276] [<ffffffff8107b0ea>] kthread+0xea/0xf0 > >> > [ 16.189165] [<ffffffff8107b000>] ? kthread_create_on_node+0x160/0x160 > >> > [ 16.195700] [<ffffffff816395dc>] ret_from_fork+0x7c/0xb0 > >> > [ 16.201109] [<ffffffff8107b000>] ? kthread_create_on_node+0x160/0x160 > >> > > >> > The actual death of the serial console occurs in acpi_device_set_power() > >> > called from: > >> > > >> > enable_slot() > >> > acpiphp_bus_add() > >> > acpiphp_bus_trim() > >> > acpi_bus_trim() > >> > acpi_walk_namespace() > >> > acpi_bus_remove() > >> > acpi_device_unregister() > >> > acpi_device_set_power() > >> > > >> > I can't seem to get a path from the acpi devices in question there, so I > >> > have no idea what's getting trimmed here. It worries me quite a bit by > >> > introducing this trimming that apparently wasn't happening before > >> > though. Thanks, > >> > >> Hi Alex: > >> Could you apply the following patch and bootup with kernel param > >> "acpiphp.acpiphp_debug=1"? > >> I guess the patch can make serial port alive. It will not > >> be put into D3cold > >> during trimming. But I don't know why it doesn't work after being put > >> back to D0. > > > > Do we actually put it into D0 in acpi_bus_scan()? I don't think so. > > > > Hi Rafael: > I mean the code in the acpiphp_bus_add(). After trimming and acpi > bus scan handle, the device will be put back to D0 if acpi_bus_get_device() > return acpi device. So I thought the serial port is put back to D0. *The* device corresponding to handle will be put into D0. Any devices below it whose ACPI device objects may also be added by acpi_bus_scan() - not necessarily. Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index e763651..359b23d 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1110,7 +1110,7 @@ static void acpi_device_unregister(struct acpi_device *device) * power resources the device depends on and turn off the ones that have * no more references. */ - acpi_device_set_power(device, ACPI_STATE_D3_COLD); + //acpi_device_set_power(device, ACPI_STATE_D3_COLD); device->handle = NULL; put_device(&device->dev);