On 17/12/20 14:09, mark wrote: > -----Original message----- >> From: mark <mark at havak.nl> >> Sent: Monday, December 14, 2020 6:15 PM >> To: Pablo Sebastián Greco <pablo at fliagreco.com.ar>; Conversations around CentOS on ARM hardware <arm-dev at centos.org> >> Subject: RE: [Arm-dev] unable to configure zram-swap on RPI 4 8G model (32bit) >> >> >> >> -----Original message----- >>> From: Pablo Sebastián Greco <pablo at fliagreco.com.ar> >>> Sent: Monday, December 14, 2020 6:00 PM >>> To: Conversations around CentOS on ARM hardware <arm-dev at centos.org>; mark >> <mark at havak.nl> >>> Subject: Re: [Arm-dev] unable to configure zram-swap on RPI 4 8G model (32bit) >>> >>> >>> On 14/12/20 13:43, mark wrote: >>>> -----Original Message----- >>>> From: Pablo Sebastián Greco <pablo at fliagreco.com.ar> >>>> Sent: maandag 14 december 2020 17:20 >>>> To: Conversations around CentOS on ARM hardware <arm-dev at centos.org>; >> mark >>> <mark at havak.nl> >>>> Subject: Re: [Arm-dev] unable to configure zram-swap on RPI 4 8G model >> (32bit) >>>> >>>> On 14/12/20 11:42, mark wrote: >>>>> Being aware using zram-swap is not a default feature on the CentOS >>>>> Userland for armv7hl, Still want to share the problem I ran in to. >>>>> >>>>> I turns out the arm 32bit kernel with large memory support OOPS if zram-swap >>> is deployed if the system has more than 4GB ram. >>>> I'm a heavy user of zram-swap, even not being default, but I have only >> used >>> with devices that have 2G max, this is interesting. Does it still happen >> if >>> you limit the size? >>>> Did not test limiting the ram to 4GB myself jet, it does according to >> : >>>> https://github.com/raspberrypi/linux/issues/3839#issuecomment-723027652 >>> I meant limiting the size of the zram-swap >> No the size of the swap does not seem matter: I tried 512, 1024 and 4096MB >> >> On a RPI4 4GB model it works just fine, >> on a 8GB model I get a "Internal error: Oops: 207" >> >> BTW running a fresh homebrew image of CentOS 7.9.2009 without a swap-partition >> and kernel: >> 5.4.72-v7l.1.el7 #1 SMP Wed Oct 21 17:20:56 UTC 2020 armv7l armv7l armv7l >> GNU/Linux >> >> >>>> >>>>> This issue seems to be addressed (verry recently) in kernel 5.4.81 (1) >>>>> >>>>> As mentioned this is verry recently, version 5.4.81 is just 12 day's >> old.. >>>>> However if there is a testbuild of this rpi2-kernel4: I'm eager to test >>> it > Just a heads-up, > > I could not figure out how to make a test build of a kernel => 5.4.81 based on the current raspberrypi2-kernel4-5.4.72 kernel. > Not knowledgeable enough to update the rpi-5.4.x.patch... My Bad > > However was able to rebuild the current kernel with the patch mentioned in the commit (1); > needed to include an other, quite harmless looking, patch in order to get it applied clean That's even better actually, because we can confirm that it actually that patch that fixes it, thanks!!! Just curious, how long did it take to rebuild the kernel? > Long story short, zram-swap works on my RPI4 8G model: > > # swapon --show > NAME TYPE SIZE USED PRIO > /dev/zram0 partition 3.7G 0B -2 > > # uname -a > Linux localhost 5.4.72-v7l.1.1.el7 #1 SMP Thu Dec 17 16:13:03 CET 2020 armv7l armv7l armv7l GNU/Linux > > # free -m > total used free shared buff/cache available > Mem: 7876 94 7469 16 312 7691 > Swap: 3755 0 3755 > > > In my (probably short lived) git repo the changes I made: > https://github.com/markVnl/Centos-raspberrypi2-kernel/tree/zram-swap-oops > > >>>> There's no test build yet, I'm still adjusting to what happened last >>>> week, but hopefully we'll have a new kernel soon >>>>> 1) https://github.com/raspberrypi/linux/commit/1bef5f25a69234613b92a0e2456870fee4a57efc >>>>> >>>>> >>>> Pablo. >>>> >>>> _______________________________________________ >>>> Arm-dev mailing list >>>> Arm-dev at centos.org >>>> https://lists.centos.org/mailman/listinfo/arm-dev Pablo.