Jens Axboe <[email protected]> writes: > On 1/17/19 5:48 AM, Roman Penyaev wrote: >> On 2019-01-16 18:49, Jens Axboe wrote: >> >> [...] >> >>> +static int io_allocate_scq_urings(struct io_ring_ctx *ctx, >>> + struct io_uring_params *p) >>> +{ >>> + struct io_sq_ring *sq_ring; >>> + struct io_cq_ring *cq_ring; >>> + size_t size; >>> + int ret; >>> + >>> + sq_ring = io_mem_alloc(struct_size(sq_ring, array, p->sq_entries)); >> >> It seems that sq_entries, cq_entries are not limited at all. Can nasty >> app consume a lot of kernel pages calling io_setup_uring() from a loop >> passing random entries number? (or even better: decreasing entries >> number, >> in order to consume all pages orders with min number of loops). > > Yes, that's an oversight, we should have a limit in place. I'll add that.
Can we charge the ring memory to the RLIMIT_MEMLOCK as well? I'd prefer not to repeat the mistake of fs.aio-max-nr. -Jeff
