block: fix 'kmem_cache of name 'bio-108' already exists'

JIRA: https://issues.redhat.com/browse/RHEL-79409

commit b654f7a
Author: Ming Lei <[email protected]>
Date:   Fri Feb 28 21:26:56 2025 +0800

    block: fix 'kmem_cache of name 'bio-108' already exists'

    Device mapper bioset often has big bio_slab size, which can be more than
    1000, then 8byte can't hold the slab name any more, cause the kmem_cache
    allocation warning of 'kmem_cache of name 'bio-108' already exists'.

    Fix the warning by extending bio_slab->name to 12 bytes, but fix output
    of /proc/slabinfo

    Reported-by: Guangwu Zhang <[email protected]>
    Signed-off-by: Ming Lei <[email protected]>
    Link: https://lore.kernel.org/r/[email protected]
    Signed-off-by: Jens Axboe <[email protected]>

Signed-off-by: Ming Lei <[email protected]>

Author: Ming Lei

block/bio.c

@@ -77,7 +77,7 @@ struct bio_slab {
 	struct kmem_cache *slab;
 	unsigned int slab_ref;
 	unsigned int slab_size;
-	char name[8];
+	char name[12];
 };
 static DEFINE_MUTEX(bio_slab_lock);
 static DEFINE_XARRAY(bio_slabs);