Re: commit 0e334db6bb4b1fd1e2d72c1f3d8f004313cd9f94 breaks timer
From: H.J. Lu
Date: Thu Jan 03 2019 - 11:53:51 EST
On Sun, Dec 30, 2018 at 6:07 PM H.J. Lu <hjl.tools@xxxxxxxxx> wrote:
> On 4.19 branch,
> commit 82c8dbb376b9fa9b831c157cbb15664cb4a343e3
> Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Date: Mon Dec 17 13:31:05 2018 +0100
> posix-timers: Fix division by zero bug
> commit 0e334db6bb4b1fd1e2d72c1f3d8f004313cd9f94 upstream.
> The signal delivery path of posix-timers can try to rearm the timer even if
> the interval is zero. That's handled for the common case (hrtimer) but not
> for alarm timers. In that case the forwarding function raises a division by
> zero exception.
> The handling for hrtimer based posix timers is wrong because it marks the
> timer as active despite the fact that it is stopped.
> Move the check from common_hrtimer_rearm() to posixtimer_rearm() to cure
> both issues.