On 04/16/2018 11:58 AM, Rafael J. Wysocki wrote: > On Mon, Apr 16, 2018 at 5:31 PM, Joseph Salisbury > <joseph.salisbury@xxxxxxxxxxxxx> wrote: >> On 04/13/2018 05:34 PM, Rafael J. Wysocki wrote: >>> On Fri, Apr 13, 2018 at 7:56 PM, Joseph Salisbury >>> <joseph.salisbury@xxxxxxxxxxxxx> wrote: >>>> Hi Rafael, >>>> >>>> A kernel bug report was opened against Ubuntu [0]. After a kernel >>>> bisect, it was found that reverting the following two commits resolved >>>> this bug: >>>> >>>> 0ce3fcaff929 ("PCI / PM: Restore PME Enable after config space restoration") >>>> 0847684cfc5f("PCI / PM: Simplify device wakeup settings code") >>>> >>>> This is a regression introduced in v4.13-rc1 and still exists in >>>> mainline. The bug causes the battery to drain when the system is >>>> powered down and unplugged, which does not happed prior to these two >>>> commits. >>> What system and what do you mean by "powered down"? How much time >>> does it take for the battery to drain now? >> By powered down, the bug reporter is saying physically powered off and >> unplugged. The system is a HP laptop: >> >> dmi.chassis.vendor: HP >> dmi.product.family: 103C_5335KV HP Notebook >> dmi.product.name: HP Notebook >> vendor_id : GenuineIntel >> cpu family : 6 >> >> >>>> The bisect actually pointed to commit de3ef1e, but reverting >>>> these two commits fixes the issue. >>>> >>>> I was hoping to get your feedback, since you are the patch author. Do >>>> you think gathering any additional data will help diagnose this issue, >>>> or would it be best to submit a revert request? >>> First, reverting these is not an option or you will break systems >>> relying on them now. 4.13 is three releases back at this point. >>> >>> Second, your issue appears to be related to the suspend/shutdown path >>> whereas commit 0ce3fcaff929 is mostly about resume, so presumably the >>> change in pci_enable_wake() causes the problem to happen. Can you try >>> to revert this one alone and see if that helps? >> A test kernel with commits 0ce3fcaff929 and de3ef1eb1cd0 reverted was >> tested. However, the test kernel still exhibited the bug. > So essentially the bisection result cannot be trusted. We performed some more testing and confirmed just a revert of the following commit resolves the bug: 0847684cfc5f0 ("PCI / PM: Simplify device wakeup settings code") Can you think of any suggestions to help debug further? -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html