On Wed, 19 Aug 2020 09:00:22 +0200, Sebastian Andrzej Siewior said: > On 2020-08-18 17:56:49 [-0700], Guenter Roeck wrote: > > Nice catch. FWIW, there is no obvious reason why this would need to be atomic. > > The calling code does not set a lock, meaning there can be two (or more) > > callers entering this code. Weird, especially since the code looks like it > > would actually need a mutex to work correctly. It might be interesting to > > see what happens if there are, say, half a dozen scripts/processes trying > > to read the hwmon attribute introduced by this patch at the same time. > > => https://lkml.kernel.org/r/20200818161439.3dkf6jzp3vuwmvvh@linutronix.de Looks reasonable to me, though I've not verified that it's preemptible at that point...