On Wed, 5 Jun 2019 at 06:41, Coly Li <colyli@xxxxxxx> wrote: > > On 2019/6/5 1:24 上午, Bjørn Forsman wrote: > > On Tue, 4 Jun 2019 at 17:41, Coly Li <colyli@xxxxxxx> wrote: > >> > >> On 2019/6/4 10:59 下午, Coly Li wrote: > >>> On 2019/6/4 7:00 下午, Bjørn Forsman wrote: > >>>> Hi all, > >>>> > >>>> I get a kernel oops from bcache when writing to > >>>> /sys/block/bcache0/bcache/writeback_percent and there is no attached > >>>> cache device. See the oops itself below my signature. > >>>> > >>>> This is on Linux 4.19.46. I looked in git and see many commits to > >>>> bcache lately, but none seem to address this particular issue. > >>>> > >>>> Background: I'm writing to .../writeback_percent with > >>>> systemd-tmpfiles. I'd rather not replace it with a script that figures > >>>> out whether or not the kernel will oops if writing to the sysfs file > >>>> -- the kernel should not oops in the first place. > >>> > >>> Hi Bjorn, > >>> > >>> Thank you for the reporting. I believe this is a case we missed in > >>> testings. When a bcache device is not attached, it does not make sense > >>> to update the writeback rate in period by the changing of writeback_percent. > >>> > >>> I will post a patch for your testing soon. > >> > >> Hi Bjorn, > >> > >> Could you please to try this patch ? Hope it may help a bit. > > > > Hi Coly, > > > > Thanks for the quick patch! I tested it on linux 5.2-rc2 and it indeed > > fixes the problem. > > > > There is one typo in the patch/commit message: s/writebac/writeback/ > > > > Hi Bjorn, > > Thanks for the patch review. Do you mind if I add Reviewed-By: tag with > your name and email address ? Yes, you can add my Reviewed-By: tag. -- Bjørn Forsman
