Re: [PATCH v2] kdb: use ktime_get_mono_fast_ns() instead of ktime_get_ts()

From: Arnd Bergmann
Date: Tue Jan 30 2018 - 08:35:31 EST


On Mon, Jan 29, 2018 at 3:22 AM, Baolin Wang <baolin.wang@xxxxxxxxxx> wrote:
> The kdb code will print the monotonic time by ktime_get_ts(), but
> the ktime_get_ts() will be protected by a sequence lock, that will
> introduce one deadlock risk if the lock was already held in the
> context from which we entered the debugger.
>
> Thus we can use the ktime_get_mono_fast_ns() to get the monotonic
> time, which is NMI safe access to clock monotonic. Moreover we can
> remove the 'struct timespec', which is not y2038 safe.
>
> Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>

Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx>