Public bug reported: [Impact] BT fails to load firmware after S3. On my system it's atheros' chip, but the same issue can be seen with broadcom's chip, too. [542.6274] WARNING: CPU: 0 PID: 20729 at /build/linux-MD8jsN/linux-4.4.0/drivers/base/firmware_class.c:1148 _request_firmware+0x7c2/0xaf0()
The root cause of this issue is request_firmware() is being called at the wrong time. [Fix] The fix is from this old thread[1], but the patch didn't be accepted by the maintainer. It prevents the work queue from being re-created and calls request_firmware() immediately before usermodehelper is fully resumed. Making the workqueue freezable preserves the delay and will postpone the firmware loading time. [Test Case] Verified on the machine has this issue, and confirm this patch works. [Regression Potential] >From what I can see, I think this change should be safe, and after 240 times >S3 test, the system and BT functions are still working. 1. http://lists.openwall.net/netdev/2015/05/06/3 ** Affects: linux (Ubuntu) Importance: Undecided Assignee: AceLan Kao (acelankao) Status: In Progress -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1706833 Title: atheros bt failed after S3 Status in linux package in Ubuntu: In Progress Bug description: [Impact] BT fails to load firmware after S3. On my system it's atheros' chip, but the same issue can be seen with broadcom's chip, too. [542.6274] WARNING: CPU: 0 PID: 20729 at /build/linux-MD8jsN/linux-4.4.0/drivers/base/firmware_class.c:1148 _request_firmware+0x7c2/0xaf0() The root cause of this issue is request_firmware() is being called at the wrong time. [Fix] The fix is from this old thread[1], but the patch didn't be accepted by the maintainer. It prevents the work queue from being re-created and calls request_firmware() immediately before usermodehelper is fully resumed. Making the workqueue freezable preserves the delay and will postpone the firmware loading time. [Test Case] Verified on the machine has this issue, and confirm this patch works. [Regression Potential] From what I can see, I think this change should be safe, and after 240 times S3 test, the system and BT functions are still working. 1. http://lists.openwall.net/netdev/2015/05/06/3 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1706833/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
