From: Jason Wang <[email protected]> Date: Thu, 8 Feb 2018 11:59:25 +0800
> We need limit the maximum size of queue, otherwise it may cause > several side effects e.g slab will warn when the size exceeds > KMALLOC_MAX_SIZE. Using KMALLOC_MAX_SIZE still looks too so this patch > tries to limit it to 64K. This value could be revisited if we found a > real case that needs more. > > Reported-by: [email protected] > Fixes: 2e0ab8ca83c12 ("ptr_ring: array based FIFO for pointers") > Signed-off-by: Jason Wang <[email protected]> ... > @@ -466,6 +468,8 @@ static inline int ptr_ring_consume_batched_bh(struct > ptr_ring *r, > > static inline void **__ptr_ring_init_queue_alloc(unsigned int size, gfp_t > gfp) > { > + if (size > PTR_RING_MAX_ALLOC) > + return NULL; > return kvmalloc_array(size, sizeof(void *), gfp | __GFP_ZERO); > } This doesn't limit the allocation to 64K. It limits it to 64K * sizeof(void *).
