FS#16855 - [kernel26] Enable CONFIG_PM_DEBUG by default

Attached to Project: Arch Linux
Opened by Anonymous Submitter - Monday, 26 October 2009, 21:01 GMT
Last edited by Tobias Powalowski (tpowa) - Saturday, 26 December 2009, 07:23 GMT
Task Type Feature Request
Category Kernel
Status Closed
Assigned To Tobias Powalowski (tpowa)
Thomas Bächler (brain0)
Architecture All
Severity Low
Priority Normal
Reported Version
Due in Version Undecided
Due Date Undecided
Percent Complete 100%
Votes 0
Private No



I've just found that suspend and hibernate on my Dell Mini 9 has stopped working, which seems to have coincided with the release of the 2.6.31 kernel. I've had no trouble with it in the past six or so months. I've made no recent hardware or software configuration changes that I think could have caused this, other than enabling Intel graphics KMS. Disabling that didn't help.

The basic-pm-debugging.txt file in the Linux kernel source Documentation/power/ subdirectory describes debugging techniques using a file called /sys/power/pm_test, however, that is only available if CONFIG_PM_DEBUG is enabled at kernel compile time.

Because suspend/hibernate are probably commonly used functions for people with laptops, I'd like to suggest that the CONFIG_PM_DEBUG option be enabled in the default Arch Linux kernel. This would make it much easier for people to diagnose suspend/hibernate problems.

Additional info:
* kernel26, i686
This task depends upon

Closed by  Tobias Powalowski (tpowa)
Saturday, 26 December 2009, 07:23 GMT
Reason for closing:  Fixed
Additional comments about closing:  2.6.32 series
Comment by Matthew Gyurgyik (pyther) - Saturday, 07 November 2009, 20:00 GMT
I would disagree. I feel that debug output should only be enabled if necessary. If you need debug support you could always compile it in. By enabling debug it will just add a lot of unnecessary clutter to dmesg, making it harder for regular users to find helpful information.
Comment by Laszlo Papp (djszapi) - Saturday, 07 November 2009, 22:34 GMT
I agree with Matthew here, and debug facility can grow the size, and If i need any kernel option that archlinux doesn't support, I compile own-kernel, that's the best way maybe, because so much user would have so much request so that not to implement.
Comment by Anonymous Submitter - Monday, 09 November 2009, 07:19 GMT
If you read the document I specifed, you'll find it says:

"To use one of them it is necessary to write the corresponding string to /sys/power/pm_test (eg. "devices" to test the freezing of processes and suspending devices)"

so, no, it won't generate debug output unless you tell it to.