Re: [PATCH v2 2/3] mm/swap: use swap_ops to register swap device's methods

[Barry Song <21cnbao@gmail.com>]

On Sun, Mar 29, 2026 at 6:49 PM kernel test robot <lkp@intel.com> wrote:
>
> Hi Barry,
>
> kernel test robot noticed the following build errors:
>
> [auto build test ERROR on akpm-mm/mm-everything]
>
> url:    https://github.com/intel-lab-lkp/linux/commits/Barry-Song/mm-swap-rename-mm-page_io-c-to-mm-swap_io-c/20260328-170852
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
> patch link:    https://lore.kernel.org/r/20260328075812.11060-3-21cnbao%40gmail.com
> patch subject: [PATCH v2 2/3] mm/swap: use swap_ops to register swap device's methods
> config: arm-randconfig-001-20260329 (https://download.01.org/0day-ci/archive/20260329/202603291844.TWh2Ellp-lkp@intel.com/config)
> compiler: clang version 23.0.0git (https://github.com/llvm/llvm-project 054e11d1a17e5ba88bb1a8ef32fad3346e80b186)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260329/202603291844.TWh2Ellp-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 <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202603291844.TWh2Ellp-lkp@intel.com/
>
> All errors (new ones prefixed by >>):
>
> >> mm/zswap.c:1057:19: error: use of undeclared identifier 'sis'; did you mean 'si'?
>     1057 |         VM_WARN_ON_ONCE(!sis->ops || !sis->ops->write_folio);
>          |                          ^~~
>          |                          si
>    include/linux/mmdebug.h:133:52: note: expanded from macro 'VM_WARN_ON_ONCE'
>      133 | #define VM_WARN_ON_ONCE(cond) BUILD_BUG_ON_INVALID(cond)
>          |                                                    ^~~~
>    include/linux/build_bug.h:30:63: note: expanded from macro 'BUILD_BUG_ON_INVALID'
>       30 | #define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e))))
>          |                                                               ^
>    mm/zswap.c:995:27: note: 'si' declared here
>      995 |         struct swap_info_struct *si;
>          |                                  ^
>    mm/zswap.c:1057:32: error: use of undeclared identifier 'sis'; did you mean 'si'?
>     1057 |         VM_WARN_ON_ONCE(!sis->ops || !sis->ops->write_folio);
>          |                                       ^~~
>          |                                       si

Deeply sorry for the last-minute edit—I fat-fingered it.
It should be si, not sis. My sincere apologies.

diff --git a/mm/zswap.c b/mm/zswap.c
index 9bacb1733e1c..b60821758169 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -1054,7 +1054,7 @@ static int zswap_writeback_entry(struct zswap_entry *entry,
 	folio_set_reclaim(folio);
 
 	/* start writeback */
-	VM_WARN_ON_ONCE(!sis->ops || !sis->ops->write_folio);
+	VM_WARN_ON_ONCE(!si->ops || !si->ops->write_folio);
 	si->ops->write_folio(si, folio, NULL);
 
 out:
-- 
Best Regards
Barry