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| author | Masahiro Yamada <masahiroy@kernel.org> | 2022-09-23 13:38:35 +0200 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2022-09-23 16:46:19 +0200 |
| commit | f7f04d198334d6f69c76c8f8675194551a3da574 (patch) | |
| tree | 4f1bc13e86ba6c75ec054ace85eddb938201d1ab /lib | |
| parent | MAINTAINERS: merge SWIOTLB SUBSYSTEM into DMA MAPPING HELPERS (diff) | |
| download | linux-f7f04d198334d6f69c76c8f8675194551a3da574.tar.xz linux-f7f04d198334d6f69c76c8f8675194551a3da574.zip | |
lib/sg_pool: change module_init(sg_pool_init) to subsys_initcall
sg_alloc_table_chained() is called by several drivers, but if it is
called before sg_pool_init(), it results in a NULL pointer dereference
in sg_pool_alloc().
Since commit 9b1d6c895002 ("lib: scatterlist: move SG pool code from
SCSI driver to lib/sg_pool.c"), we rely on module_init(sg_pool_init)
is invoked before other module_init calls but this assumption is
fragile.
I slightly changed the link order while refactoring Kbuild, then
uncovered this issue. I should keep the current link order, but
depending on a specific call order among module_init is so fragile.
We usually define the init order by specifying *_initcall correctly,
or delay the driver probing by returning -EPROBE_DEFER.
Change module_initcall() to subsys_initcall(), and also delete the
pointless module_exit() because lib/sg_pool.c is always compiled as
built-in. (CONFIG_SG_POOL is bool)
Link: https://lore.kernel.org/all/20220921043946.GA1355561@roeck-us.net/
Link: https://lore.kernel.org/all/8e70837d-d859-dfb2-bf7f-83f8b31467bc@samsung.com/
Fixes: 9b1d6c895002 ("lib: scatterlist: move SG pool code from SCSI driver to lib/sg_pool.c")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/sg_pool.c | 16 |
1 files changed, 2 insertions, 14 deletions
diff --git a/lib/sg_pool.c b/lib/sg_pool.c index a0b1a52cd6f7..9bfe60ca3f37 100644 --- a/lib/sg_pool.c +++ b/lib/sg_pool.c @@ -1,5 +1,5 @@ // SPDX-License-Identifier: GPL-2.0-only -#include <linux/module.h> +#include <linux/init.h> #include <linux/scatterlist.h> #include <linux/mempool.h> #include <linux/slab.h> @@ -177,16 +177,4 @@ cleanup_sdb: return -ENOMEM; } -static __exit void sg_pool_exit(void) -{ - int i; - - for (i = 0; i < SG_MEMPOOL_NR; i++) { - struct sg_pool *sgp = sg_pools + i; - mempool_destroy(sgp->pool); - kmem_cache_destroy(sgp->slab); - } -} - -module_init(sg_pool_init); -module_exit(sg_pool_exit); +subsys_initcall(sg_pool_init); |