On Wed, Apr 25, 2018 at 09:46:42AM +0900, Tetsuo Handa wrote:
Theodore Ts'o wrote:
We can do a sleeping allocation from an irq context when CONFIG_NUMA is enabled. Fix this by initializing the NUMA crng instances in a workqueue.
Offloading to workqueue context itself would be OK, but this patch makes linux.git unbootable because
if (crng == &primary_crng && crng_init < 2) { invalidate_batched_entropy(); numa_crng_init(); // <= Deferred to workqueue context. crng_init = 2; // <= Not waiting for workqueue context, and oops before console becomes ready. ;-) process_random_ready_list(); wake_up_interruptible(&crng_init_wait); pr_notice("random: crng init done\n"); }
Please don't pretend rng_ready() before workqueue context is processed.
Where's the oops? It's not oopsing for me, and if the NUMA crng is not initailized, the code in extract_entropy returns falls back to using the primary_crng:
static void extract_crng(__u32 out[CHACHA20_BLOCK_WORDS]) { struct crng_state *crng = NULL;
#ifdef CONFIG_NUMA if (crng_node_pool) crng = crng_node_pool[numa_node_id()]; if (crng == NULL) #endif crng = &primary_crng; _extract_crng(crng, out); }
- Ted