Re: [Regression] acpi: laptop panics early in boot

["Pierre Asselin" <pa@panix.com>]

> This mail didn't make it into the archive on lore.kernel.org. Did
> someone receive it? If not, that would explain why I didn't get any
> feedback on it ...

First time I see it.

>> diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
>> index 9531dd0fef50..fddca263ac40 100644
>> --- a/drivers/acpi/bus.c
>> +++ b/drivers/acpi/bus.c
>> @@ -518,13 +518,15 @@ static void acpi_bus_notify(acpi_handle handle,
>> u32 type, void *data)
>>  	if (!adev)
>>  		goto err;
>>
>> -	if (adev->dev.driver) {
>> +	device_lock(&adev->dev);
>> +	if (device_is_bound(&adev->dev)) {
>>  		struct acpi_driver *driver = to_acpi_driver(adev->dev.driver);
>>
>>  		if (driver && driver->ops.notify &&
>>  		    (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
>>  			driver->ops.notify(adev, type);
>>  	}
>> +	device_unlock(&adev->dev);
>>
>>  	if (!hotplug_event) {
>>  		acpi_put_acpi_dev(adev);
>>

This patch works, in that the kernel reaches early userspace reliably.
I would want to test it more extensively, i.e. install the modules and
run it for real instead of just kexec-ing the bzImage.  I'll test Rafael's
patch first.

Full disclosure: I made small changes to the starting .config, see below.
6.3-rc1 is still bad with the new .config, the patch makes it good.
The changes:
  1) PROVE_LOCKING=y
  2) CONFIG_DEBUG_ATOMIC_SLEEP=y  (why not, what could go wrong :)
  3) radeon driver modular instead of built-in.
I don't think it matters.  Here is the diffconfig, just in case.

-EXTRA_FIRMWARE_DIR "/lib/firmware"
 CEC_CORE y -> m
 DEBUG_ATOMIC_SLEEP n -> y
 DEBUG_LOCK_ALLOC n -> y
 DEBUG_MUTEXES n -> y
 DEBUG_RT_MUTEXES n -> y
 DEBUG_RWSEMS n -> y
 DEBUG_SPINLOCK n -> y
 DEBUG_WW_MUTEX_SLOWPATH n -> y
 DRM_DISPLAY_HELPER y -> m
 DRM_KMS_HELPER y -> m
 DRM_RADEON y -> m
 DRM_TTM y -> m
 DRM_TTM_HELPER y -> m
 EXTRA_FIRMWARE "radeon/R300_cp.bin" -> ""
 FB_CFB_COPYAREA y -> m
 FB_CFB_FILLRECT y -> m
 FB_CFB_IMAGEBLIT y -> m
 FB_SYS_COPYAREA y -> m
 FB_SYS_FILLRECT y -> m
 FB_SYS_FOPS y -> m
 FB_SYS_IMAGEBLIT y -> m
 I2C_ALGOBIT y -> m
 PROVE_LOCKING n -> y
+DEBUG_LOCKDEP n
+LOCKDEP y
+LOCKDEP_BITS 15
+LOCKDEP_CHAINS_BITS 16
+LOCKDEP_CIRCULAR_QUEUE_BITS 12
+LOCKDEP_STACK_TRACE_BITS 19
+LOCKDEP_STACK_TRACE_HASH_BITS 14
+PREEMPTIRQ_TRACEPOINTS y
+PROVE_RAW_LOCK_NESTING n
+PROVE_RCU y
+TRACE_IRQFLAGS y
+TRACE_IRQFLAGS_NMI y