* [PATCH] fs: binfmt_elf_efpic: fix variable set but not used warning
@ 2025-03-07 6:11 sunliming
2025-03-07 14:47 ` Jan Kara
0 siblings, 1 reply; 4+ messages in thread
From: sunliming @ 2025-03-07 6:11 UTC (permalink / raw)
To: viro, brauner, jack, kees, ebiederm
Cc: linux-fsdevel, linux-mm, linux-kernel, sunliming, kernel test robot
From: sunliming <sunliming@kylinos.cn>
Fix below kernel warning:
fs/binfmt_elf_fdpic.c:1024:52: warning: variable 'excess1' set but not
used [-Wunused-but-set-variable]
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: sunliming <sunliming@kylinos.cn>
---
fs/binfmt_elf_fdpic.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index e3cf2801cd64..bed13ee8bfec 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -1024,8 +1024,11 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
/* deal with each load segment separately */
phdr = params->phdrs;
for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
- unsigned long maddr, disp, excess, excess1;
+ unsigned long maddr, disp, excess;
int prot = 0, flags;
+#ifdef CONFIG_MMU
+ unsigned long excess1;
+#endif
if (phdr->p_type != PT_LOAD)
continue;
@@ -1120,9 +1123,9 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
* extant in the file
*/
excess = phdr->p_memsz - phdr->p_filesz;
- excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
#ifdef CONFIG_MMU
+ excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
if (excess > excess1) {
unsigned long xaddr = maddr + phdr->p_filesz + excess1;
unsigned long xmaddr;
--
2.25.1
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] fs: binfmt_elf_efpic: fix variable set but not used warning
2025-03-07 6:11 [PATCH] fs: binfmt_elf_efpic: fix variable set but not used warning sunliming
@ 2025-03-07 14:47 ` Jan Kara
2025-03-07 20:30 ` Kees Cook
0 siblings, 1 reply; 4+ messages in thread
From: Jan Kara @ 2025-03-07 14:47 UTC (permalink / raw)
To: sunliming
Cc: viro, brauner, jack, kees, ebiederm, linux-fsdevel, linux-mm,
linux-kernel, sunliming, kernel test robot
On Fri 07-03-25 14:11:28, sunliming@linux.dev wrote:
> From: sunliming <sunliming@kylinos.cn>
>
> Fix below kernel warning:
> fs/binfmt_elf_fdpic.c:1024:52: warning: variable 'excess1' set but not
> used [-Wunused-but-set-variable]
>
> Reported-by: kernel test robot <lkp@intel.com>
> Signed-off-by: sunliming <sunliming@kylinos.cn>
The extra ifdef is not pretty but I guess it's better. Feel free to add:
Reviewed-by: Jan Kara <jack@suse.cz>
Honza
> ---
> fs/binfmt_elf_fdpic.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
> index e3cf2801cd64..bed13ee8bfec 100644
> --- a/fs/binfmt_elf_fdpic.c
> +++ b/fs/binfmt_elf_fdpic.c
> @@ -1024,8 +1024,11 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
> /* deal with each load segment separately */
> phdr = params->phdrs;
> for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
> - unsigned long maddr, disp, excess, excess1;
> + unsigned long maddr, disp, excess;
> int prot = 0, flags;
> +#ifdef CONFIG_MMU
> + unsigned long excess1;
> +#endif
>
> if (phdr->p_type != PT_LOAD)
> continue;
> @@ -1120,9 +1123,9 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
> * extant in the file
> */
> excess = phdr->p_memsz - phdr->p_filesz;
> - excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
>
> #ifdef CONFIG_MMU
> + excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
> if (excess > excess1) {
> unsigned long xaddr = maddr + phdr->p_filesz + excess1;
> unsigned long xmaddr;
> --
> 2.25.1
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] fs: binfmt_elf_efpic: fix variable set but not used warning
2025-03-07 14:47 ` Jan Kara
@ 2025-03-07 20:30 ` Kees Cook
2025-03-08 2:21 ` Sunliming
0 siblings, 1 reply; 4+ messages in thread
From: Kees Cook @ 2025-03-07 20:30 UTC (permalink / raw)
To: Jan Kara
Cc: sunliming, viro, brauner, ebiederm, linux-fsdevel, linux-mm,
linux-kernel, sunliming, kernel test robot
On Fri, Mar 07, 2025 at 03:47:28PM +0100, Jan Kara wrote:
> On Fri 07-03-25 14:11:28, sunliming@linux.dev wrote:
> > From: sunliming <sunliming@kylinos.cn>
> >
> > Fix below kernel warning:
> > fs/binfmt_elf_fdpic.c:1024:52: warning: variable 'excess1' set but not
> > used [-Wunused-but-set-variable]
> >
> > Reported-by: kernel test robot <lkp@intel.com>
> > Signed-off-by: sunliming <sunliming@kylinos.cn>
>
> The extra ifdef is not pretty but I guess it's better. Feel free to add:
>
> Reviewed-by: Jan Kara <jack@suse.cz>
Since we allow loop-scope variable definitions now, perhaps this is a
case for defining the variable later within the #ifdef, like this?
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index e3cf2801cd64..b0ef71238328 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -1024,7 +1024,7 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
/* deal with each load segment separately */
phdr = params->phdrs;
for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
- unsigned long maddr, disp, excess, excess1;
+ unsigned long maddr, disp, excess;
int prot = 0, flags;
if (phdr->p_type != PT_LOAD)
@@ -1120,9 +1120,10 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
* extant in the file
*/
excess = phdr->p_memsz - phdr->p_filesz;
- excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
#ifdef CONFIG_MMU
+ const unsigned long excess1 =
+ PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
if (excess > excess1) {
unsigned long xaddr = maddr + phdr->p_filesz + excess1;
unsigned long xmaddr;
>
> Honza
>
> > ---
> > fs/binfmt_elf_fdpic.c | 7 +++++--
> > 1 file changed, 5 insertions(+), 2 deletions(-)
> >
> > diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
> > index e3cf2801cd64..bed13ee8bfec 100644
> > --- a/fs/binfmt_elf_fdpic.c
> > +++ b/fs/binfmt_elf_fdpic.c
> > @@ -1024,8 +1024,11 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
> > /* deal with each load segment separately */
> > phdr = params->phdrs;
> > for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
> > - unsigned long maddr, disp, excess, excess1;
> > + unsigned long maddr, disp, excess;
> > int prot = 0, flags;
> > +#ifdef CONFIG_MMU
> > + unsigned long excess1;
> > +#endif
> >
> > if (phdr->p_type != PT_LOAD)
> > continue;
> > @@ -1120,9 +1123,9 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
> > * extant in the file
> > */
> > excess = phdr->p_memsz - phdr->p_filesz;
> > - excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
> >
> > #ifdef CONFIG_MMU
> > + excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
> > if (excess > excess1) {
> > unsigned long xaddr = maddr + phdr->p_filesz + excess1;
> > unsigned long xmaddr;
> > --
> > 2.25.1
> >
> --
> Jan Kara <jack@suse.com>
> SUSE Labs, CR
--
Kees Cook
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] fs: binfmt_elf_efpic: fix variable set but not used warning
2025-03-07 20:30 ` Kees Cook
@ 2025-03-08 2:21 ` Sunliming
0 siblings, 0 replies; 4+ messages in thread
From: Sunliming @ 2025-03-08 2:21 UTC (permalink / raw)
To: Kees Cook, Jan Kara
Cc: viro, brauner, ebiederm, linux-fsdevel, linux-mm, linux-kernel,
sunliming, kernel test robot
On 2025/3/8 04:30, Kees Cook wrote:
> On Fri, Mar 07, 2025 at 03:47:28PM +0100, Jan Kara wrote:
>> On Fri 07-03-25 14:11:28, sunliming@linux.dev wrote:
>>> From: sunliming <sunliming@kylinos.cn>
>>>
>>> Fix below kernel warning:
>>> fs/binfmt_elf_fdpic.c:1024:52: warning: variable 'excess1' set but not
>>> used [-Wunused-but-set-variable]
>>>
>>> Reported-by: kernel test robot <lkp@intel.com>
>>> Signed-off-by: sunliming <sunliming@kylinos.cn>
>> The extra ifdef is not pretty but I guess it's better. Feel free to add:
>>
>> Reviewed-by: Jan Kara <jack@suse.cz>
> Since we allow loop-scope variable definitions now, perhaps this is a
> case for defining the variable later within the #ifdef, like this?
>
>
> diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
> index e3cf2801cd64..b0ef71238328 100644
> --- a/fs/binfmt_elf_fdpic.c
> +++ b/fs/binfmt_elf_fdpic.c
> @@ -1024,7 +1024,7 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
> /* deal with each load segment separately */
> phdr = params->phdrs;
> for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
> - unsigned long maddr, disp, excess, excess1;
> + unsigned long maddr, disp, excess;
> int prot = 0, flags;
>
> if (phdr->p_type != PT_LOAD)
> @@ -1120,9 +1120,10 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
> * extant in the file
> */
> excess = phdr->p_memsz - phdr->p_filesz;
> - excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
>
> #ifdef CONFIG_MMU
> + const unsigned long excess1 =
> + PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
> if (excess > excess1) {
> unsigned long xaddr = maddr + phdr->p_filesz + excess1;
> unsigned long xmaddr;
I think this is a good idea. I will resend this patch in this way，thanks.
>> Honza
>>
>>> ---
>>> fs/binfmt_elf_fdpic.c | 7 +++++--
>>> 1 file changed, 5 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
>>> index e3cf2801cd64..bed13ee8bfec 100644
>>> --- a/fs/binfmt_elf_fdpic.c
>>> +++ b/fs/binfmt_elf_fdpic.c
>>> @@ -1024,8 +1024,11 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
>>> /* deal with each load segment separately */
>>> phdr = params->phdrs;
>>> for (loop = 0; loop < params->hdr.e_phnum; loop++, phdr++) {
>>> - unsigned long maddr, disp, excess, excess1;
>>> + unsigned long maddr, disp, excess;
>>> int prot = 0, flags;
>>> +#ifdef CONFIG_MMU
>>> + unsigned long excess1;
>>> +#endif
>>>
>>> if (phdr->p_type != PT_LOAD)
>>> continue;
>>> @@ -1120,9 +1123,9 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
>>> * extant in the file
>>> */
>>> excess = phdr->p_memsz - phdr->p_filesz;
>>> - excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
>>>
>>> #ifdef CONFIG_MMU
>>> + excess1 = PAGE_SIZE - ((maddr + phdr->p_filesz) & ~PAGE_MASK);
>>> if (excess > excess1) {
>>> unsigned long xaddr = maddr + phdr->p_filesz + excess1;
>>> unsigned long xmaddr;
>>> --
>>> 2.25.1
>>>
>> --
>> Jan Kara <jack@suse.com>
>> SUSE Labs, CR
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2025-03-07 6:11 [PATCH] fs: binfmt_elf_efpic: fix variable set but not used warning sunliming
2025-03-07 14:47 ` Jan Kara
2025-03-07 20:30 ` Kees Cook
2025-03-08 2:21 ` Sunliming
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