Re: [PATCH -next] module: fix build error when CONFIG_SYSFS is disabled

Re: [PATCH -next] module: fix build error when CONFIG_SYSFS is disabled

[Stephen Boyd]

Quoting Bixuan Cui (2021-05-25 01:54:00)
>  kernel/module.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/module.c b/kernel/module.c
> index decf4601e943..7287ecc76714 100644
> --- a/kernel/module.c
> +++ b/kernel/module.c
> @@ -2794,7 +2794,8 @@ static void add_kallsyms(struct module *mod, const struct load_info *info)
>  }
>  #endif /* CONFIG_KALLSYMS */
>
> -#if IS_ENABLED(CONFIG_KALLSYMS) && IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID)
> +#if IS_ENABLED(CONFIG_KALLSYMS) && IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) && \
> +       IS_ENABLED(CONFIG_SYSFS)

Thanks for the report. It is the wrong fix though as we don't care that
sysfs is enabled or not. How about this patch?

---8<---
diff --git a/kernel/module.c b/kernel/module.c
index b5dd92e35b02..5be1f8ea4886 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1462,6 +1462,13 @@ resolve_symbol_wait(struct module *mod,
 	return ksym;
 }

+#ifdef CONFIG_KALLSYMS
+static inline bool sect_empty(const Elf_Shdr *sect)
+{
+	return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
+}
+#endif
+
 /*
  * /sys/module/foo/sections stuff
  * J. Corbet <corbet@lwn.net>
@@ -1469,11 +1476,6 @@ resolve_symbol_wait(struct module *mod,
 #ifdef CONFIG_SYSFS

 #ifdef CONFIG_KALLSYMS
-static inline bool sect_empty(const Elf_Shdr *sect)
-{
-	return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
-}
-
 struct module_sect_attr {
 	struct bin_attribute battr;
 	unsigned long address;

Re: [PATCH -next] module: fix build error when CONFIG_SYSFS is disabled

[Bixuan Cui]

On 2021/5/25 15:36, Stephen Boyd wrote:
> Quoting Bixuan Cui (2021-05-25 01:54:00)
>>  kernel/module.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/kernel/module.c b/kernel/module.c
>> index decf4601e943..7287ecc76714 100644
>> --- a/kernel/module.c
>> +++ b/kernel/module.c
>> @@ -2794,7 +2794,8 @@ static void add_kallsyms(struct module *mod, const struct load_info *info)
>>  }
>>  #endif /* CONFIG_KALLSYMS */
>>
>> -#if IS_ENABLED(CONFIG_KALLSYMS) && IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID)
>> +#if IS_ENABLED(CONFIG_KALLSYMS) && IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) && \
>> +       IS_ENABLED(CONFIG_SYSFS)
> Thanks for the report. It is the wrong fix though as we don't care that
> sysfs is enabled or not. How about this patch?
Hello, your patch solves that problem very well. Will you send a new patch?

Thanks
Bixuan Cui

[PATCH -next] module: fix build error when CONFIG_SYSFS is disabled

[Bixuan Cui]

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Fix build error when disable CONFIG_SYSFS:
kernel/module.c:2805:8: error: implicit declaration of function ‘sect_empty’; did you mean ‘desc_empty’? [-Werror=implicit-function-declaration]
 2805 |   if (!sect_empty(sechdr) && sechdr->sh_type == SHT_NOTE &&

Fixes: 9ee6682aa528 ("module: add printk formats to add module build ID to stacktraces")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
---
 kernel/module.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/module.c b/kernel/module.c
index decf4601e943..7287ecc76714 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2794,7 +2794,8 @@ static void add_kallsyms(struct module *mod, const struct load_info *info)
 }
 #endif /* CONFIG_KALLSYMS */
 
-#if IS_ENABLED(CONFIG_KALLSYMS) && IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID)
+#if IS_ENABLED(CONFIG_KALLSYMS) && IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) && \
+	IS_ENABLED(CONFIG_SYSFS)
 static void init_build_id(struct module *mod, const struct load_info *info)
 {
 	const Elf_Shdr *sechdr;
-- 
2.17.1

Re: [PATCH -next] module: fix build error when CONFIG_SYSFS is disabled

[Bixuan Cui]

I will send a new, thanks.