On Thu, Aug 1, 2019 at 10:15 AM Andrea Righi <[email protected]> wrote:
> Thanks Ryan, this is very interesting: > > [ 259.411486] bcache: register_bcache() error /dev/vdg: device already > registered (emitting change event) > [ 259.537070] bcache: register_bcache() error /dev/vdg: device already > registered (emitting change event) > [ 259.797830] bcache: register_bcache() error /dev/vdg: device already > registered (emitting change event) > [ 259.900392] bcache: register_bcache() error /dev/vdg: device already > registered (emitting change event) > > It looks that we're trying to register /dev/vdg multiple times as a > backing device (make-bcache -B). I'm not getting this message during my > tests, so that might be required to reproduce that particular deadlock. > We carry a specific sauce patch to ensure that if the cacheset is already online, and a backing device shows up later, that the kernel emits the change event to trigger the udev rules to generate the symlink for /dev/bcache/by-uuid. I don't think the patch we carry is at issue since we are just detecting the re-register scenario and emitting a change uevent; https://www.spinics.net/lists/linux-bcache/msg05833.html We may want to resubmit that now to see if they'll take that or even want to deal with the scenario in a cleaner way; > > I'll modify my test case to trigger these errors and see if I can > reproduce the hung task timeout issue. > I can provide you a setup to reproduce this. I'll put together a doc. > -- > You received this bug notification because you are subscribed to the bug > report. > https://bugs.launchpad.net/bugs/1796292 > > Title: > Tight timeout for bcache removal causes spurious failures > > To manage notifications about this bug go to: > https://bugs.launchpad.net/curtin/+bug/1796292/+subscriptions > -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1796292 Title: Tight timeout for bcache removal causes spurious failures To manage notifications about this bug go to: https://bugs.launchpad.net/curtin/+bug/1796292/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
