Re: [PATCH 4.19 041/133] Revert "usb/ohci-platform: Fix a warning when hibernating"

Hi! On Mon 2020-07-20 17:36:28, Greg Kroah-Hartman wrote:

This reverts commit c83258a757687ffccce37ed73dba56cc6d4b8a1b.

Eugeniu Rosca writes:

On Thu, Jul 09, 2020 at 09:00:23AM +0200, Eugeniu Rosca wrote:

...

After integrating v4.14.186 commit 5410d158ca2a50 ("usb/ehci-platform: Set PM runtime as active on resume") into downstream v4.14.x, we started to consistently experience below panic [1] on every second s2ram of R-Car H3 Salvator-X Renesas reference board.

After some investigations, we concluded the following:

• the issue does not exist in vanilla v5.8-rc4+
• [bisecting shows that] the panic on v4.14.186 is caused by the lack of v5.6-rc1 commit 987351e1ea7772 ("phy: core: Add consumer device link support"). Getting evidence for that is easy. Reverting 987351e1ea7772 in vanilla leads to a similar backtrace [2].

Questions:

• Backporting 987351e1ea7772 ("phy: core: Add consumer device link support") to v4.14.187 looks challenging enough, so probably not worth it. Anybody to contradict this?

I'm not sure about v4.14.187, but backport to v4.19 is quite simple (just ignore single non-existing file) and passes basic testing.

Would that be better solution for 4.19 and newer?

...

• Assuming no plans to backport the missing mainline commit to v4.14.x, should the following three v4.14.186 commits be reverted on v4.14.x?
  • baef809ea497a4 ("usb/ohci-platform: Fix a warning when hibernating")
  • 9f33eff4958885 ("usb/xhci-plat: Set PM runtime as active on resume")
  • 5410d158ca2a50 ("usb/ehci-platform: Set PM runtime as active on resume")

Best regards, Pavel