Re: [PATCH 1/2] [xarry]:Fixed an issue with memory allocated using the GFP_KERNEL flag in spinlocks

From: Matthew Wilcox
Date: Tue Nov 03 2020 - 21:36:16 EST


On Wed, Nov 04, 2020 at 10:32:12AM +0800, xiaofeng.yan wrote:
> xa_lock_irq(xa);
> - curr = __xa_store(xa, index, entry, gfp);
> + curr = __xa_store(xa, index, entry, GFP_ATOMIC);
> xa_unlock_irq(xa);

You haven't actually seen a bug, have you? You just read the code
wrongly.

void *__xa_store(struct xarray *xa, unsigned long index, void *entry, gfp_t gfp)
...
} while (__xas_nomem(&xas, gfp));
...
if (gfpflags_allow_blocking(gfp)) {
xas_unlock_type(xas, lock_type);
xas->xa_alloc = kmem_cache_alloc(radix_tree_node_cachep, gfp);
xas_lock_type(xas, lock_type);