I think powerpc really need to pick the tricks from other architectures
to make cmpxchg work on __bitwise fields.

On Mon, Jun 01, 2026 at 11:26:16PM +0800, kernel test robot wrote:

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux.git for-7.0/block
head:   72f4d6fca699a1e35b39c5e5dacac2926d254135
commit: b37fbce460ad60b0c4449c1c7566cf24f3016713 [19/138] blk-crypto: optimize bio splitting in blk_crypto_fallback_encrypt_bio
config: powerpc64-randconfig-r111-20260601 (https://download.01.org/0day-ci/archive/20260601/202606012339.rZAl6Xq8-lkp@intel.com/config)
compiler: powerpc64-linux-gcc (GCC) 8.5.0
sparse: v0.6.5-rc1
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260601/202606012339.rZAl6Xq8-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot [off-list ref]
| Closes: https://lore.kernel.org/oe-kbuild-all/202606012339.rZAl6Xq8-lkp@intel.com/ (local)

sparse warnings: (new ones prefixed by >>)

quoted

quoted

block/blk-crypto-fallback.c:154:17: sparse: sparse: cast from restricted blk_status_t
block/blk-crypto-fallback.c:154:17: sparse: sparse: cast from restricted blk_status_t

   block/blk-crypto-fallback.c:154:17: sparse: sparse: cast to restricted blk_status_t

vim +154 block/blk-crypto-fallback.c

   143	
   144	static void blk_crypto_fallback_encrypt_endio(struct bio *enc_bio)
   145	{
   146		struct bio *src_bio = enc_bio->bi_private;
   147		int i;
   148	
   149		for (i = 0; i < enc_bio->bi_vcnt; i++)
   150			mempool_free(enc_bio->bi_io_vec[i].bv_page,
   151				     blk_crypto_bounce_page_pool);
   152	
   153		if (enc_bio->bi_status)
 > 154			cmpxchg(&src_bio->bi_status, 0, enc_bio->bi_status);
   155	
   156		bio_put(enc_bio);
   157		bio_endio(src_bio);
   158	}
   159	

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

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