Hi David, I'm really sorry, I just submitted the patch for version V2 and didn't notice your reply email. Here is an explanation about the environment used for compilation: Firstly, I opened the configuration startup option CONFIG_WERROR=y Secondly, when I tested with versions 9.4.0 and 12.3.1 of gcc, I encountered errors: $ gcc --version gcc (Ubuntu 9.4.0-1ubuntu1~20.04.1) 9.4.0 $ make mm/vmscan.o CALL scripts/checksyscalls.sh DESCEND bpf/resolve_btfids INSTALL libsubcmd_headers CC mm/vmscan.o In file included from ./include/linux/init.h:5, from ./include/linux/printk.h:6, from ./include/asm-generic/bug.h:22, from ./arch/arm64/include/asm/bug.h:26, from ./include/linux/bug.h:5, from ./include/linux/mmdebug.h:5, from ./include/linux/mm.h:6, from mm/vmscan.c:15: mm/vmscan.c: In function ¡®read_ctrl_pos¡¯: ./include/linux/build_bug.h:78:41: error: static assertion failed: "min(tier, 4U - 1) signedness error, fix types or consider umin() before min_t()" 78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg) | ^~~~~~~~~~~~~~ ./include/linux/build_bug.h:77:34: note: in expansion of macro ¡®__static_assert¡¯ 77 | #define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr) | ^~~~~~~~~~~~~~~ ./include/linux/minmax.h:51:2: note: in expansion of macro ¡®static_assert¡¯ 51 | static_assert(__types_ok(x, y), \ | ^~~~~~~~~~~~~ ./include/linux/minmax.h:58:3: note: in expansion of macro ¡®__cmp_once¡¯ 58 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y))) | ^~~~~~~~~~ ./include/linux/minmax.h:85:19: note: in expansion of macro ¡®__careful_cmp¡¯ 85 | #define min(x, y) __careful_cmp(min, x, y) | ^~~~~~~~~~~~~ mm/vmscan.c:3098:37: note: in expansion of macro ¡®min¡¯ 3098 | for (i = tier % MAX_NR_TIERS; i <= min(tier, MAX_NR_TIERS - 1); i++) { | ^~~ make[3]: *** [scripts/Makefile.build:243: mm/vmscan.o] Error 1 make[2]: *** [scripts/Makefile.build:480: mm] Error 2 make[1]: *** [/home/user/fffs/klinux/Makefile:1944: .] Error 2 make: *** [Makefile:236: __sub-make] Error 2 $ gcc --version gcc (GCC) 12.3.1 (kylin 12.3.1-31.p02.ky11) $ make mm/vmscan.o CALL scripts/checksyscalls.sh DESCEND bpf/resolve_btfids make[4]: ¡°install_headers¡±is already the latest. CC mm/vmscan.o In file included from ./include/linux/init.h:5, from ./include/linux/printk.h:6, from ./include/asm-generic/bug.h:22, from ./arch/arm64/include/asm/bug.h:26, from ./include/linux/bug.h:5, from ./include/linux/mmdebug.h:5, from ./include/linux/mm.h:6, from mm/vmscan.c:15: mm/vmscan.c: In function ¡®read_ctrl_pos¡¯: ./include/linux/build_bug.h:78:41: error£ºstatic assertion failed£º"min(tier, 4U - 1) signedness error, fix types or consider umin() before min_t()" 78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg) | ^~~~~~~~~~~~~~ ./include/linux/build_bug.h:77:34: note£ºin expansion of macro ¡®__static_assert¡¯ 77 | #define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr) | ^~~~~~~~~~~~~~~ ./include/linux/minmax.h:51:9: note£ºin expansion of macro ¡®static_assert¡¯ 51 | static_assert(__types_ok(x, y), \ | ^~~~~~~~~~~~~ ./include/linux/minmax.h:58:17: note£ºin expansion of macro ¡®__cmp_once¡¯ 58 | __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y))) | ^~~~~~~~~~ ./include/linux/minmax.h:85:25: note£ºin expansion of macro ¡®__careful_cmp¡¯ 85 | #define min(x, y) __careful_cmp(min, x, y) | ^~~~~~~~~~~~~ mm/vmscan.c:3098:44: note£ºin expansion of macro ¡®min¡¯ 3098 | for (i = tier % MAX_NR_TIERS; i <= min(tier, MAX_NR_TIERS - 1); i++) { | ^~~ make[3]: *** [scripts/Makefile.build:243£ºmm/vmscan.o] Error 1 make[2]: *** [scripts/Makefile.build:480£ºmm] Error 2 make[1]: *** [/root/fffs/klinux/Makefile:1944£º.] Error2 make: *** [Makefile:236£º__sub-make] Error 2 Sorry again. At 2025-08-08 17:58:31, "David Hildenbrand" wrote: >On 08.08.25 11:54, Qingshuang Fu wrote: >> From: Qingshuang Fu >> >> Due to the fact that the tier data type in min (tier, MAX_CR_TIERS -1) >> is int,but MAX_CR_TIERS is an unsigned type, directly using >> the min function for comparison will result in an error: >> >> from mm/vmscan.c:15: >> mm/vmscan.c: In function ¡®read_ctrl_pos¡¯: >> ./include/linux/build_bug.h:78:41: error: static assertion failed: >> "min(tier, 4U - 1) signedness error, fix types or >> consider umin() before min_t()" >> >> Fixes: 37a260870f2c ("mm/mglru: rework type selection") >> Suggested-by: David Hildenbrand > >You keep ignoring my feedback and I can only reproduce this with W=2 >where there are like a bunch of other issues, this here doesn't move the >needle. > >So I'm afraid I cannot spend any more time on reviewing this patch. > >NAK > >-- >Cheers, > >David / dhildenb