On 2024-08-05 17:56:22 [+0100], Mark Brown wrote: > On Mon, Aug 05, 2024 at 05:33:09PM +0200, Sebastian Andrzej Siewior wrote: > > > I'm not sure if making the lock a raw_spinlock_t solves all the > > problems. The regmap is regmap_mmio so direct memory-access and looks > > simple enough to do so. In regmap_mmio_write() I see clk_enable() and > > and this uses a spinlock_t so we should be back at the same problem. > > The clk_enable() is optional, users simply shouldn't use the internal > clock management with devices that it'll cause problems for. > > > There might be an additional problem if reg-caching is enabled. > > The flat cache is there mostly for the benefit of things accessed from > interrupt context, it guarantees to never do any allocations and doesn't > lock. You can also use other caches if you ensure that any registers > accessed in interrupt context are already cached so won't trigger any > new allocations. My point is simply that those two things could complicate things further if the desired fix is to (always) use raw_spinlock_t. Sebastian
