Public bug reported: [Impact] SOF driver in oem-5.6 kernel tries to access HDA codec register when the codec is already suspended. This may freeze suspend.
[Fix] Revert HDA codec PM direct-complete optimization. The same suspend optimization works perfectly on 5.8 and 5.10 kernel, so something's wrong in the SOF driver in oem-5.6. However, SOF in oem-5.6 is in Frankenstein state so we better not touch it. [Test] Suspend a laptop with SOF driver, it can take 30 seconds to suspend, or worse, it freezes. With the patch applied, it can suspend in 1 second. [Regression Risk] For HDA codecs that benefit from this PM optimization, it'll take longer to suspend and resume. Nothing else changes other than that. ** Affects: hwe-next Importance: Undecided Status: New ** Affects: linux-oem-5.6 (Ubuntu) Importance: Undecided Status: Invalid ** Affects: linux-oem-5.6 (Ubuntu Focal) Importance: High Status: Confirmed ** Tags: oem-priority originate-from-1908495 stella ** Also affects: linux-oem-5.6 (Ubuntu Focal) Importance: Undecided Status: New ** Changed in: linux-oem-5.6 (Ubuntu) Status: New => Invalid ** Changed in: linux-oem-5.6 (Ubuntu Focal) Status: New => Confirmed ** Changed in: linux-oem-5.6 (Ubuntu Focal) Importance: Undecided => High ** Tags added: oem-priority originate-from-1908495 stella -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-oem-5.6 in Ubuntu. https://bugs.launchpad.net/bugs/1908713 Title: Fix suspend error of SOF driver Status in HWE Next: New Status in linux-oem-5.6 package in Ubuntu: Invalid Status in linux-oem-5.6 source package in Focal: Confirmed Bug description: [Impact] SOF driver in oem-5.6 kernel tries to access HDA codec register when the codec is already suspended. This may freeze suspend. [Fix] Revert HDA codec PM direct-complete optimization. The same suspend optimization works perfectly on 5.8 and 5.10 kernel, so something's wrong in the SOF driver in oem-5.6. However, SOF in oem-5.6 is in Frankenstein state so we better not touch it. [Test] Suspend a laptop with SOF driver, it can take 30 seconds to suspend, or worse, it freezes. With the patch applied, it can suspend in 1 second. [Regression Risk] For HDA codecs that benefit from this PM optimization, it'll take longer to suspend and resume. Nothing else changes other than that. To manage notifications about this bug go to: https://bugs.launchpad.net/hwe-next/+bug/1908713/+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