On Mon, 2016-10-17 at 16:24 +0200, Sebastian Andrzej Siewior wrote: > On 2016-10-16 05:14:22 [+0200], Mike Galbraith wrote: > > > > In v4.7, the driver switched to percpu compression streams, disabling > > preemption (get/put_cpu_ptr()). Use get/put_cpu_light() instead. > > I am not convinced that this will work. Nothing prevents > zram_bvec_write() to be reentrant on the same CPU what I can tell from > browsing over the code and since it uses zstrm->buffer for compression > it can go wrong. Also I don't know if crypto's tfm handler can be used > in parallel for any ops (it usually does not work for crypto). > > I suggest a local lock or a good reason why the this patch works. I used a local lock first, but lockdep was unhappy with it. Ok, back to the drawing board. Seems to work, but... -Mike -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
