Ups I just realised I didn't sent the message to the mailing list, but instead send it to greg only; Basically the problem was happening a month ago on version 4.20.7 ,I have reported it to my distros bug report but I didn't got any response about it. It was consistent on every reboot and shutdown. Even installing a kernel package which previously didn't had any issues didn't fixed the issue so kernels 4.20 - 4.20.7 were also eating one of my cpu cores. (I didn't had any other older version at the time because I did a clean install of windows and then of linux). I run linux with 1 less cpu core for about a week until I found out that I can disable autosuspend. I tried to trigger the error this time around on versions 4.20-4.20.13 even on 4.20.7 where it first occured. And it refuses to happen again, the only thing I really have from this occurrence is perf data, which I used to find out which kernel module was eating my cpu core. This issue was happening regardless of connected usb devices and regardless of whether I was putting the machine to sleep or not. pon., 4 mar 2019 o 13:28 Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> napisał(a): > > On 3.3.2019 16.30, Greg KH wrote: > > On Sun, Mar 03, 2019 at 03:15:27PM +0100, Farelka kek wrote: > >> usbcore.autosuspend higher than -1, causes 1 cpu core to never step > >> down from kernel mode. > > > > Some hardware does not aupport autosuspend, so leaving it at -1 is good. > > > >> It happens on a core i5-7200U laptop, an acer f5-573g-50ec > >> Disabling usb autosuspend causes the cpu not to idle at, minimum of > >> 25% cpu usage. > > > > Is this a regression from earlier kernel versions? If so, any chance > > you can run 'git bisect' to find the offending commit? > > > > It could be the following patch: > > 2f31a67 usb: xhci: Prevent bus suspend if a port connect change or polling state is detected > > It caused similar issues on MacBookPro because of broken usb card reader stuck > in polling state. > > Farelka kek, If that's the case for you, could you try a fix I wrote? > I added the fix on top of 4.20.13 in a suspend_fix branch: > > git://git.kernel.org/pub/scm/linux/kernel/git/mnyman/xhci.git suspend_fix > https://git.kernel.org/pub/scm/linux/kernel/git/mnyman/xhci.git/commit/?h=suspend_fix > > -Mathias
