include/linux/vmstat.h | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
Compiler is confused when we do arithmetic operations between two
different enum types.
In this case NR_VM_STAT_ITEMS and NR_LRU_BASE are not actual
enumerators, they are used to find the first and the count of the
enumerator.
Add a casting to int, to avoid the following llvm 9 warning:
./include/linux/vmstat.h:504:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
504 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~ ^
505 | item];
| ~~~~
./include/linux/vmstat.h:511:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
511 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~ ^
512 | NR_VM_NUMA_EVENT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~~
./include/linux/vmstat.h:518:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
518 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
| ~~~~~~~~~~~ ^ ~~~
./include/linux/vmstat.h:524:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
524 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~ ^
525 | NR_VM_NUMA_EVENT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
include/linux/vmstat.h | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
index d2761bf8ff32..32c641d25bea 100644
--- a/include/linux/vmstat.h
+++ b/include/linux/vmstat.h
@@ -501,27 +501,26 @@ static inline const char *zone_stat_name(enum zone_stat_item item)
#ifdef CONFIG_NUMA
static inline const char *numa_stat_name(enum numa_stat_item item)
{
- return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
- item];
+ return vmstat_text[(int)NR_VM_ZONE_STAT_ITEMS + item];
}
#endif /* CONFIG_NUMA */
static inline const char *node_stat_name(enum node_stat_item item)
{
- return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
+ return vmstat_text[(int)NR_VM_ZONE_STAT_ITEMS +
NR_VM_NUMA_EVENT_ITEMS +
item];
}
static inline const char *lru_list_name(enum lru_list lru)
{
- return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
+ return node_stat_name((int)NR_LRU_BASE + lru) + 3; // skip "nr_"
}
#if defined(CONFIG_VM_EVENT_COUNTERS) || defined(CONFIG_MEMCG)
static inline const char *vm_event_name(enum vm_event_item item)
{
- return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
+ return vmstat_text[(int)NR_VM_ZONE_STAT_ITEMS +
NR_VM_NUMA_EVENT_ITEMS +
NR_VM_NODE_STAT_ITEMS +
NR_VM_STAT_ITEMS +
---
base-commit: 40384c840ea1944d7c5a392e8975ed088ecf0b37
change-id: 20241202-fix-vmstat-88968bcaa955
Best regards,
--
Ricardo Ribalda <ribalda@chromium.org>Hi Ricardo,
kernel test robot noticed the following build errors:
[auto build test ERROR on 40384c840ea1944d7c5a392e8975ed088ecf0b37]
url: https://github.com/intel-lab-lkp/linux/commits/Ricardo-Ribalda/mm-vmstat-h-Annotate-operations-between-enums/20241203-020840
base: 40384c840ea1944d7c5a392e8975ed088ecf0b37
patch link: https://lore.kernel.org/r/20241202-fix-vmstat-v1-1-c995585b7df5%40chromium.org
patch subject: [PATCH] mm: vmstat.h: Annotate operations between enums
config: x86_64-randconfig-004-20241216 (https://download.01.org/0day-ci/archive/20241216/202412160507.MwWr4a9B-lkp@intel.com/config)
compiler: clang version 19.1.3 (https://github.com/llvm/llvm-project ab51eccf88f5321e7c60591c5546b254b6afab99)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241216/202412160507.MwWr4a9B-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/202412160507.MwWr4a9B-lkp@intel.com/
All errors (new ones prefixed by >>):
>> drivers/gpu/drm/amd/amdgpu/../display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c:7021:13: error: stack frame size (3096) exceeds limit (3072) in 'dml_core_mode_support' [-Werror,-Wframe-larger-than]
7021 | static bool dml_core_mode_support(struct dml2_core_calcs_mode_support_ex *in_out_params)
| ^
1 error generated.
--
>> drivers/gpu/drm/amd/amdgpu/../display/dc/dml2/display_mode_core.c:6712:12: error: stack frame size (4088) exceeds limit (3072) in 'dml_core_mode_support' [-Werror,-Wframe-larger-than]
6712 | dml_bool_t dml_core_mode_support(struct display_mode_lib_st *mode_lib)
| ^
1 error generated.
vim +/dml_core_mode_support +7021 drivers/gpu/drm/amd/amdgpu/../display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c
2563391e57b5a9 Chaitanya Dhere 2024-07-02 7020
70839da6360500 Aurabindo Pillai 2024-04-19 @7021 static bool dml_core_mode_support(struct dml2_core_calcs_mode_support_ex *in_out_params)
70839da6360500 Aurabindo Pillai 2024-04-19 7022 {
70839da6360500 Aurabindo Pillai 2024-04-19 7023 struct dml2_core_internal_display_mode_lib *mode_lib = in_out_params->mode_lib;
70839da6360500 Aurabindo Pillai 2024-04-19 7024 const struct dml2_display_cfg *display_cfg = in_out_params->in_display_cfg;
70839da6360500 Aurabindo Pillai 2024-04-19 7025 const struct dml2_mcg_min_clock_table *min_clk_table = in_out_params->min_clk_table;
70839da6360500 Aurabindo Pillai 2024-04-19 7026
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Ricardo,
On Mon, Dec 02, 2024 at 04:02:19PM +0000, Ricardo Ribalda wrote:
> Compiler is confused when we do arithmetic operations between two
> different enum types.
> In this case NR_VM_STAT_ITEMS and NR_LRU_BASE are not actual
> enumerators, they are used to find the first and the count of the
> enumerator.
>
> Add a casting to int, to avoid the following llvm 9 warning:
> ./include/linux/vmstat.h:504:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
> 504 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
> | ~~~~~~~~~~~~~~~~~~~~~ ^
> 505 | item];
> | ~~~~
> ./include/linux/vmstat.h:511:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
> 511 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
> | ~~~~~~~~~~~~~~~~~~~~~ ^
> 512 | NR_VM_NUMA_EVENT_ITEMS +
> | ~~~~~~~~~~~~~~~~~~~~~~
> ./include/linux/vmstat.h:518:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
> 518 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
> | ~~~~~~~~~~~ ^ ~~~
> ./include/linux/vmstat.h:524:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
> 524 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
> | ~~~~~~~~~~~~~~~~~~~~~ ^
> 525 | NR_VM_NUMA_EVENT_ITEMS +
> | ~~~~~~~~~~~~~~~~~~~~~~
>
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
I think it is just better to disable this specific warning for normal
and W=1 builds so that it is not visible for people, as this objectively
makes the code uglier:
https://lore.kernel.org/20241008005136.GA241099@thelio-3990X/
https://lore.kernel.org/20241017-disable-two-clang-enum-warnings-v2-1-163ac04346ae@kernel.org/
I have just pinged that patch for acceptance.
Cheers,
Nathan
> ---
> include/linux/vmstat.h | 9 ++++-----
> 1 file changed, 4 insertions(+), 5 deletions(-)
>
> diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
> index d2761bf8ff32..32c641d25bea 100644
> --- a/include/linux/vmstat.h
> +++ b/include/linux/vmstat.h
> @@ -501,27 +501,26 @@ static inline const char *zone_stat_name(enum zone_stat_item item)
> #ifdef CONFIG_NUMA
> static inline const char *numa_stat_name(enum numa_stat_item item)
> {
> - return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
> - item];
> + return vmstat_text[(int)NR_VM_ZONE_STAT_ITEMS + item];
> }
> #endif /* CONFIG_NUMA */
>
> static inline const char *node_stat_name(enum node_stat_item item)
> {
> - return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
> + return vmstat_text[(int)NR_VM_ZONE_STAT_ITEMS +
> NR_VM_NUMA_EVENT_ITEMS +
> item];
> }
>
> static inline const char *lru_list_name(enum lru_list lru)
> {
> - return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
> + return node_stat_name((int)NR_LRU_BASE + lru) + 3; // skip "nr_"
> }
>
> #if defined(CONFIG_VM_EVENT_COUNTERS) || defined(CONFIG_MEMCG)
> static inline const char *vm_event_name(enum vm_event_item item)
> {
> - return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
> + return vmstat_text[(int)NR_VM_ZONE_STAT_ITEMS +
> NR_VM_NUMA_EVENT_ITEMS +
> NR_VM_NODE_STAT_ITEMS +
> NR_VM_STAT_ITEMS +
>
> ---
> base-commit: 40384c840ea1944d7c5a392e8975ed088ecf0b37
> change-id: 20241202-fix-vmstat-88968bcaa955
>
> Best regards,
> --
> Ricardo Ribalda <ribalda@chromium.org>
>
On Mon, 2 Dec 2024 at 17:18, Nathan Chancellor <nathan@kernel.org> wrote:
>
> Hi Ricardo,
>
> On Mon, Dec 02, 2024 at 04:02:19PM +0000, Ricardo Ribalda wrote:
> > Compiler is confused when we do arithmetic operations between two
> > different enum types.
> > In this case NR_VM_STAT_ITEMS and NR_LRU_BASE are not actual
> > enumerators, they are used to find the first and the count of the
> > enumerator.
> >
> > Add a casting to int, to avoid the following llvm 9 warning:
> > ./include/linux/vmstat.h:504:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
> > 504 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
> > | ~~~~~~~~~~~~~~~~~~~~~ ^
> > 505 | item];
> > | ~~~~
> > ./include/linux/vmstat.h:511:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
> > 511 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
> > | ~~~~~~~~~~~~~~~~~~~~~ ^
> > 512 | NR_VM_NUMA_EVENT_ITEMS +
> > | ~~~~~~~~~~~~~~~~~~~~~~
> > ./include/linux/vmstat.h:518:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
> > 518 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
> > | ~~~~~~~~~~~ ^ ~~~
> > ./include/linux/vmstat.h:524:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
> > 524 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
> > | ~~~~~~~~~~~~~~~~~~~~~ ^
> > 525 | NR_VM_NUMA_EVENT_ITEMS +
> > | ~~~~~~~~~~~~~~~~~~~~~~
> >
> > Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
>
> I think it is just better to disable this specific warning for normal
> and W=1 builds so that it is not visible for people, as this objectively
> makes the code uglier:
>
> https://lore.kernel.org/20241008005136.GA241099@thelio-3990X/
>
> https://lore.kernel.org/20241017-disable-two-clang-enum-warnings-v2-1-163ac04346ae@kernel.org/
Thanks for the heads-up.
Either disabling the config or this patch will work for my usecase (media-ci).
FWIW, we only need 3 patches (plus this) to build media with W=1 and llvm19....
I do not think that this patch is very ugly :P
>
> I have just pinged that patch for acceptance.
>
> Cheers,
> Nathan
>
> > ---
> > include/linux/vmstat.h | 9 ++++-----
> > 1 file changed, 4 insertions(+), 5 deletions(-)
> >
> > diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
> > index d2761bf8ff32..32c641d25bea 100644
> > --- a/include/linux/vmstat.h
> > +++ b/include/linux/vmstat.h
> > @@ -501,27 +501,26 @@ static inline const char *zone_stat_name(enum zone_stat_item item)
> > #ifdef CONFIG_NUMA
> > static inline const char *numa_stat_name(enum numa_stat_item item)
> > {
> > - return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
> > - item];
> > + return vmstat_text[(int)NR_VM_ZONE_STAT_ITEMS + item];
> > }
> > #endif /* CONFIG_NUMA */
> >
> > static inline const char *node_stat_name(enum node_stat_item item)
> > {
> > - return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
> > + return vmstat_text[(int)NR_VM_ZONE_STAT_ITEMS +
> > NR_VM_NUMA_EVENT_ITEMS +
> > item];
> > }
> >
> > static inline const char *lru_list_name(enum lru_list lru)
> > {
> > - return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
> > + return node_stat_name((int)NR_LRU_BASE + lru) + 3; // skip "nr_"
> > }
> >
> > #if defined(CONFIG_VM_EVENT_COUNTERS) || defined(CONFIG_MEMCG)
> > static inline const char *vm_event_name(enum vm_event_item item)
> > {
> > - return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
> > + return vmstat_text[(int)NR_VM_ZONE_STAT_ITEMS +
> > NR_VM_NUMA_EVENT_ITEMS +
> > NR_VM_NODE_STAT_ITEMS +
> > NR_VM_STAT_ITEMS +
> >
> > ---
> > base-commit: 40384c840ea1944d7c5a392e8975ed088ecf0b37
> > change-id: 20241202-fix-vmstat-88968bcaa955
> >
> > Best regards,
> > --
> > Ricardo Ribalda <ribalda@chromium.org>
> >
--
Ricardo Ribalda
© 2016 - 2026 Red Hat, Inc.