** Description changed: [Impact] - cntvct_el0 could be left untrapped if reset with the user access bit set + This bug captures a few issues with the ARM arch_timer driver: + + 1) Some arm64 systems have hardware defects in their architected timer + implementations that require errata, which we workaround in the kernel. + However, it's possible that this workaround will not be applied if the + timer was reset w/ the user access bit set. + + 2) The Juno board fails to initialize a timer at boot: + + arch_timer: Unable to map frame @ 0x0000000000000000 + arch_timer: Frame missing phys irq. + Failed to initialize '/timer@2a810000': -22 + + 3) Possible boot warning from arch_timer_mem_of_init(): + 'Trying to vfree() nonexistent vm area' + + 4) There's a theoretical problem where the first frame of a timer could + be used even though a better suited timer frame is available. + + 5) An infinite recursion loop will occur when enabling the function + tracer in builds with CONFIG_PREEMPT_TRACER=y. Ubuntu does not enable + CONFIG_PREEMPT_TRACER, so this will only be a problem if that changes. [Test Case] + [Regression Risk]
** Changed in: linux (Ubuntu) Status: Incomplete => Confirmed -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1713821 Title: arm64 arch_timer fixes To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1713821/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs