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* [PATCH v4 1/1] x86, relocs: add printf attribute to die()
@ 2017-03-05 14:12 Nicolas Iooss
  2017-03-07  9:16 ` Ingo Molnar
  0 siblings, 1 reply; 6+ messages in thread
From: Nicolas Iooss @ 2017-03-05 14:12 UTC (permalink / raw)
  To: Thomas Gleixner, Ingo Molnar, H. Peter Anvin, x86
  Cc: linux-kernel, Nicolas Iooss

Adding such an attribute helps to detect errors in the format string at
build time. After doing this, the compiler complains about some issues:

    arch/x86/tools/relocs.c:460:5: error: format specifies type 'int'
    but the argument has type 'Elf64_Xword' (aka 'unsigned long')
    [-Werror,-Wformat]
                                    sec->shdr.sh_size);
                                    ^~~~~~~~~~~~~~~~~
    arch/x86/tools/relocs.c:464:5: error: format specifies type 'int'
    but the argument has type 'Elf64_Off' (aka 'unsigned long')
    [-Werror,-Wformat]
                                    sec->shdr.sh_offset, strerror(errno));
                                    ^~~~~~~~~~~~~~~~~~~

When relocs.c is included by relocs_32.c, sec->shdr.sh_size and
sec->shdr.sh_offset are 32-bit unsigned integers. When the file is
included by relocs_64.c, these expressions are 64-bit unsigned integers.

Add casts to unsigned long long, which length is always 64-bit, and use
%llu to format sec->shdr.sh_size and sec->shdr.sh_offset in relocs.c.

While at it, constify the format attribute of die().

Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
---
 arch/x86/tools/relocs.c        | 31 +++++++++++++++++--------------
 arch/x86/tools/relocs.h        |  3 ++-
 arch/x86/tools/relocs_common.c |  2 +-
 3 files changed, 20 insertions(+), 16 deletions(-)

diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
index 73eb7fd4aec4..3cc02065c677 100644
--- a/arch/x86/tools/relocs.c
+++ b/arch/x86/tools/relocs.c
@@ -397,8 +397,8 @@ static void read_shdrs(FILE *fp)
 		    ehdr.e_shnum);
 	}
 	if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) {
-		die("Seek to %d failed: %s\n",
-			ehdr.e_shoff, strerror(errno));
+		die("Seek to %llu failed: %s\n",
+			(unsigned long long)ehdr.e_shoff, strerror(errno));
 	}
 	for (i = 0; i < ehdr.e_shnum; i++) {
 		struct section *sec = &secs[i];
@@ -431,12 +431,13 @@ static void read_strtabs(FILE *fp)
 		}
 		sec->strtab = malloc(sec->shdr.sh_size);
 		if (!sec->strtab) {
-			die("malloc of %d bytes for strtab failed\n",
-				sec->shdr.sh_size);
+			die("malloc of %llu bytes for strtab failed\n",
+				(unsigned long long)sec->shdr.sh_size);
 		}
 		if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
-			die("Seek to %d failed: %s\n",
-				sec->shdr.sh_offset, strerror(errno));
+			die("Seek to %llu failed: %s\n",
+				(unsigned long long)sec->shdr.sh_offset,
+				strerror(errno));
 		}
 		if (fread(sec->strtab, 1, sec->shdr.sh_size, fp)
 		    != sec->shdr.sh_size) {
@@ -456,12 +457,13 @@ static void read_symtabs(FILE *fp)
 		}
 		sec->symtab = malloc(sec->shdr.sh_size);
 		if (!sec->symtab) {
-			die("malloc of %d bytes for symtab failed\n",
-				sec->shdr.sh_size);
+			die("malloc of %llu bytes for symtab failed\n",
+				(unsigned long long)sec->shdr.sh_size);
 		}
 		if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
-			die("Seek to %d failed: %s\n",
-				sec->shdr.sh_offset, strerror(errno));
+			die("Seek to %llu failed: %s\n",
+				(unsigned long long)sec->shdr.sh_offset,
+				strerror(errno));
 		}
 		if (fread(sec->symtab, 1, sec->shdr.sh_size, fp)
 		    != sec->shdr.sh_size) {
@@ -489,12 +491,13 @@ static void read_relocs(FILE *fp)
 		}
 		sec->reltab = malloc(sec->shdr.sh_size);
 		if (!sec->reltab) {
-			die("malloc of %d bytes for relocs failed\n",
-				sec->shdr.sh_size);
+			die("malloc of %llu bytes for relocs failed\n",
+				(unsigned long long)sec->shdr.sh_size);
 		}
 		if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
-			die("Seek to %d failed: %s\n",
-				sec->shdr.sh_offset, strerror(errno));
+			die("Seek to %llu failed: %s\n",
+				(unsigned long long)sec->shdr.sh_offset,
+				strerror(errno));
 		}
 		if (fread(sec->reltab, 1, sec->shdr.sh_size, fp)
 		    != sec->shdr.sh_size) {
diff --git a/arch/x86/tools/relocs.h b/arch/x86/tools/relocs.h
index 1d23bf953a4a..f41416c31608 100644
--- a/arch/x86/tools/relocs.h
+++ b/arch/x86/tools/relocs.h
@@ -16,7 +16,8 @@
 #include <regex.h>
 #include <tools/le_byteshift.h>
 
-void die(char *fmt, ...) __attribute__((noreturn));
+void die(const char *fmt, ...) __attribute__((noreturn))
+	__attribute__((format(printf, 1, 2)));
 
 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 
diff --git a/arch/x86/tools/relocs_common.c b/arch/x86/tools/relocs_common.c
index acab636bcb34..30adb44eff79 100644
--- a/arch/x86/tools/relocs_common.c
+++ b/arch/x86/tools/relocs_common.c
@@ -1,6 +1,6 @@
 #include "relocs.h"
 
-void die(char *fmt, ...)
+void die(const char *fmt, ...)
 {
 	va_list ap;
 	va_start(ap, fmt);
-- 
2.11.1

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH v4 1/1] x86, relocs: add printf attribute to die()
  2017-03-05 14:12 [PATCH v4 1/1] x86, relocs: add printf attribute to die() Nicolas Iooss
@ 2017-03-07  9:16 ` Ingo Molnar
  2017-03-07 12:37   ` Nicolas Iooss
  0 siblings, 1 reply; 6+ messages in thread
From: Ingo Molnar @ 2017-03-07  9:16 UTC (permalink / raw)
  To: Nicolas Iooss
  Cc: Thomas Gleixner, Ingo Molnar, H. Peter Anvin, x86, linux-kernel


* Nicolas Iooss <nicolas.iooss_linux@m4x.org> wrote:

> Adding such an attribute helps to detect errors in the format string at
> build time. After doing this, the compiler complains about some issues:
> 
>     arch/x86/tools/relocs.c:460:5: error: format specifies type 'int'
>     but the argument has type 'Elf64_Xword' (aka 'unsigned long')
>     [-Werror,-Wformat]
>                                     sec->shdr.sh_size);
>                                     ^~~~~~~~~~~~~~~~~
>     arch/x86/tools/relocs.c:464:5: error: format specifies type 'int'
>     but the argument has type 'Elf64_Off' (aka 'unsigned long')
>     [-Werror,-Wformat]
>                                     sec->shdr.sh_offset, strerror(errno));
>                                     ^~~~~~~~~~~~~~~~~~~
> 
> When relocs.c is included by relocs_32.c, sec->shdr.sh_size and
> sec->shdr.sh_offset are 32-bit unsigned integers. When the file is
> included by relocs_64.c, these expressions are 64-bit unsigned integers.
> 
> Add casts to unsigned long long, which length is always 64-bit, and use
> %llu to format sec->shdr.sh_size and sec->shdr.sh_offset in relocs.c.
> 
> While at it, constify the format attribute of die().
> 
> Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
> ---
>  arch/x86/tools/relocs.c        | 31 +++++++++++++++++--------------
>  arch/x86/tools/relocs.h        |  3 ++-
>  arch/x86/tools/relocs_common.c |  2 +-
>  3 files changed, 20 insertions(+), 16 deletions(-)
> 
> diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
> index 73eb7fd4aec4..3cc02065c677 100644
> --- a/arch/x86/tools/relocs.c
> +++ b/arch/x86/tools/relocs.c
> @@ -397,8 +397,8 @@ static void read_shdrs(FILE *fp)
>  		    ehdr.e_shnum);
>  	}
>  	if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) {
> -		die("Seek to %d failed: %s\n",
> -			ehdr.e_shoff, strerror(errno));
> +		die("Seek to %llu failed: %s\n",
> +			(unsigned long long)ehdr.e_shoff, strerror(errno));

Isn't "(u64)" shorter to write?

Thanks,

	Ingo

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v4 1/1] x86, relocs: add printf attribute to die()
  2017-03-07  9:16 ` Ingo Molnar
@ 2017-03-07 12:37   ` Nicolas Iooss
  2017-03-28 21:06     ` Nicolas Iooss
  0 siblings, 1 reply; 6+ messages in thread
From: Nicolas Iooss @ 2017-03-07 12:37 UTC (permalink / raw)
  To: Ingo Molnar
  Cc: Thomas Gleixner, Ingo Molnar, H. Peter Anvin, x86, linux-kernel

On Tue, Mar 7, 2017 at 10:16 AM, Ingo Molnar <mingo@kernel.org> wrote:
>
> * Nicolas Iooss <nicolas.iooss_linux@m4x.org> wrote:
>
>> Adding such an attribute helps to detect errors in the format string at
>> build time. After doing this, the compiler complains about some issues:
>>
>>     arch/x86/tools/relocs.c:460:5: error: format specifies type 'int'
>>     but the argument has type 'Elf64_Xword' (aka 'unsigned long')
>>     [-Werror,-Wformat]
>>                                     sec->shdr.sh_size);
>>                                     ^~~~~~~~~~~~~~~~~
>>     arch/x86/tools/relocs.c:464:5: error: format specifies type 'int'
>>     but the argument has type 'Elf64_Off' (aka 'unsigned long')
>>     [-Werror,-Wformat]
>>                                     sec->shdr.sh_offset, strerror(errno));
>>                                     ^~~~~~~~~~~~~~~~~~~
>>
>> When relocs.c is included by relocs_32.c, sec->shdr.sh_size and
>> sec->shdr.sh_offset are 32-bit unsigned integers. When the file is
>> included by relocs_64.c, these expressions are 64-bit unsigned integers.
>>
>> Add casts to unsigned long long, which length is always 64-bit, and use
>> %llu to format sec->shdr.sh_size and sec->shdr.sh_offset in relocs.c.
>>
>> While at it, constify the format attribute of die().
>>
>> Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
>> ---
>>  arch/x86/tools/relocs.c        | 31 +++++++++++++++++--------------
>>  arch/x86/tools/relocs.h        |  3 ++-
>>  arch/x86/tools/relocs_common.c |  2 +-
>>  3 files changed, 20 insertions(+), 16 deletions(-)
>>
>> diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
>> index 73eb7fd4aec4..3cc02065c677 100644
>> --- a/arch/x86/tools/relocs.c
>> +++ b/arch/x86/tools/relocs.c
>> @@ -397,8 +397,8 @@ static void read_shdrs(FILE *fp)
>>                   ehdr.e_shnum);
>>       }
>>       if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) {
>> -             die("Seek to %d failed: %s\n",
>> -                     ehdr.e_shoff, strerror(errno));
>> +             die("Seek to %llu failed: %s\n",
>> +                     (unsigned long long)ehdr.e_shoff, strerror(errno));
>
> Isn't "(u64)" shorter to write?

u64 does not seem to be defined in this file right now. Adding
"#include <linux/types.h>" defines u64 and __u64 in the following way:
- "typedef uint64_t u64;" from tools/include/linux/types.h
- "typedef unsigned long long __u64;" from /usr/include/asm-generic/int-ll64.h

uint64_t is unsigned long on x86-64 and gcc complains when using %llu
on such a type, so using a cast to u64 forces using PRIu64 too.

Nevertheless "(__u64)" is shorter than "(unsigned long long)" and
seems to work fine in my quick tests because it is always unsigned
long long (on both x86-32 and x86-64). Would you prefer to use this
cast?

Thanks,
Nicolas

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v4 1/1] x86, relocs: add printf attribute to die()
  2017-03-07 12:37   ` Nicolas Iooss
@ 2017-03-28 21:06     ` Nicolas Iooss
  2017-05-17  6:37       ` Nicolas Iooss
  0 siblings, 1 reply; 6+ messages in thread
From: Nicolas Iooss @ 2017-03-28 21:06 UTC (permalink / raw)
  To: Ingo Molnar, Thomas Gleixner, Ingo Molnar, H. Peter Anvin
  Cc: x86, linux-kernel

On Tue, Mar 7, 2017 at 1:37 PM, Nicolas Iooss
<nicolas.iooss_linux@m4x.org> wrote:
> On Tue, Mar 7, 2017 at 10:16 AM, Ingo Molnar <mingo@kernel.org> wrote:
>>
>> * Nicolas Iooss <nicolas.iooss_linux@m4x.org> wrote:
>>
>>> Adding such an attribute helps to detect errors in the format string at
>>> build time. After doing this, the compiler complains about some issues:
>>>
>>>     arch/x86/tools/relocs.c:460:5: error: format specifies type 'int'
>>>     but the argument has type 'Elf64_Xword' (aka 'unsigned long')
>>>     [-Werror,-Wformat]
>>>                                     sec->shdr.sh_size);
>>>                                     ^~~~~~~~~~~~~~~~~
>>>     arch/x86/tools/relocs.c:464:5: error: format specifies type 'int'
>>>     but the argument has type 'Elf64_Off' (aka 'unsigned long')
>>>     [-Werror,-Wformat]
>>>                                     sec->shdr.sh_offset, strerror(errno));
>>>                                     ^~~~~~~~~~~~~~~~~~~
>>>
>>> When relocs.c is included by relocs_32.c, sec->shdr.sh_size and
>>> sec->shdr.sh_offset are 32-bit unsigned integers. When the file is
>>> included by relocs_64.c, these expressions are 64-bit unsigned integers.
>>>
>>> Add casts to unsigned long long, which length is always 64-bit, and use
>>> %llu to format sec->shdr.sh_size and sec->shdr.sh_offset in relocs.c.
>>>
>>> While at it, constify the format attribute of die().
>>>
>>> Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
>>> ---
>>>  arch/x86/tools/relocs.c        | 31 +++++++++++++++++--------------
>>>  arch/x86/tools/relocs.h        |  3 ++-
>>>  arch/x86/tools/relocs_common.c |  2 +-
>>>  3 files changed, 20 insertions(+), 16 deletions(-)
>>>
>>> diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
>>> index 73eb7fd4aec4..3cc02065c677 100644
>>> --- a/arch/x86/tools/relocs.c
>>> +++ b/arch/x86/tools/relocs.c
>>> @@ -397,8 +397,8 @@ static void read_shdrs(FILE *fp)
>>>                   ehdr.e_shnum);
>>>       }
>>>       if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) {
>>> -             die("Seek to %d failed: %s\n",
>>> -                     ehdr.e_shoff, strerror(errno));
>>> +             die("Seek to %llu failed: %s\n",
>>> +                     (unsigned long long)ehdr.e_shoff, strerror(errno));
>>
>> Isn't "(u64)" shorter to write?
>
> u64 does not seem to be defined in this file right now. Adding
> "#include <linux/types.h>" defines u64 and __u64 in the following way:
> - "typedef uint64_t u64;" from tools/include/linux/types.h
> - "typedef unsigned long long __u64;" from /usr/include/asm-generic/int-ll64.h
>
> uint64_t is unsigned long on x86-64 and gcc complains when using %llu
> on such a type, so using a cast to u64 forces using PRIu64 too.
>
> Nevertheless "(__u64)" is shorter than "(unsigned long long)" and
> seems to work fine in my quick tests because it is always unsigned
> long long (on both x86-32 and x86-64). Would you prefer to use this
> cast?

Hello,
After the question I had on the 4th revision of this patch, I have not
received any reply or comment for three weeks. What should I do in
order to get this merged?

Thanks,
Nicolas

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v4 1/1] x86, relocs: add printf attribute to die()
  2017-03-28 21:06     ` Nicolas Iooss
@ 2017-05-17  6:37       ` Nicolas Iooss
  2017-05-27 19:28         ` Andy Shevchenko
  0 siblings, 1 reply; 6+ messages in thread
From: Nicolas Iooss @ 2017-05-17  6:37 UTC (permalink / raw)
  To: Ingo Molnar, Thomas Gleixner, Ingo Molnar, H. Peter Anvin
  Cc: x86, linux-kernel

Hello,

The patch I sent a few months ago still applies cleanly on top of
4.12-rc1. What should I do in order to get it merged in 4.13?

In case you no longer have my initial email, the patch has been
archived in https://patchwork.kernel.org/patch/9604651/ .

Thanks,
Nicolas

On Tue, Mar 28, 2017 at 11:06 PM, Nicolas Iooss
<nicolas.iooss_linux@m4x.org> wrote:
> On Tue, Mar 7, 2017 at 1:37 PM, Nicolas Iooss
> <nicolas.iooss_linux@m4x.org> wrote:
>> On Tue, Mar 7, 2017 at 10:16 AM, Ingo Molnar <mingo@kernel.org> wrote:
>>>
>>> * Nicolas Iooss <nicolas.iooss_linux@m4x.org> wrote:
>>>
>>>> Adding such an attribute helps to detect errors in the format string at
>>>> build time. After doing this, the compiler complains about some issues:
>>>>
>>>>     arch/x86/tools/relocs.c:460:5: error: format specifies type 'int'
>>>>     but the argument has type 'Elf64_Xword' (aka 'unsigned long')
>>>>     [-Werror,-Wformat]
>>>>                                     sec->shdr.sh_size);
>>>>                                     ^~~~~~~~~~~~~~~~~
>>>>     arch/x86/tools/relocs.c:464:5: error: format specifies type 'int'
>>>>     but the argument has type 'Elf64_Off' (aka 'unsigned long')
>>>>     [-Werror,-Wformat]
>>>>                                     sec->shdr.sh_offset, strerror(errno));
>>>>                                     ^~~~~~~~~~~~~~~~~~~
>>>>
>>>> When relocs.c is included by relocs_32.c, sec->shdr.sh_size and
>>>> sec->shdr.sh_offset are 32-bit unsigned integers. When the file is
>>>> included by relocs_64.c, these expressions are 64-bit unsigned integers.
>>>>
>>>> Add casts to unsigned long long, which length is always 64-bit, and use
>>>> %llu to format sec->shdr.sh_size and sec->shdr.sh_offset in relocs.c.
>>>>
>>>> While at it, constify the format attribute of die().
>>>>
>>>> Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
>>>> ---
>>>>  arch/x86/tools/relocs.c        | 31 +++++++++++++++++--------------
>>>>  arch/x86/tools/relocs.h        |  3 ++-
>>>>  arch/x86/tools/relocs_common.c |  2 +-
>>>>  3 files changed, 20 insertions(+), 16 deletions(-)
>>>>
>>>> diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
>>>> index 73eb7fd4aec4..3cc02065c677 100644
>>>> --- a/arch/x86/tools/relocs.c
>>>> +++ b/arch/x86/tools/relocs.c
>>>> @@ -397,8 +397,8 @@ static void read_shdrs(FILE *fp)
>>>>                   ehdr.e_shnum);
>>>>       }
>>>>       if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) {
>>>> -             die("Seek to %d failed: %s\n",
>>>> -                     ehdr.e_shoff, strerror(errno));
>>>> +             die("Seek to %llu failed: %s\n",
>>>> +                     (unsigned long long)ehdr.e_shoff, strerror(errno));
>>>
>>> Isn't "(u64)" shorter to write?
>>
>> u64 does not seem to be defined in this file right now. Adding
>> "#include <linux/types.h>" defines u64 and __u64 in the following way:
>> - "typedef uint64_t u64;" from tools/include/linux/types.h
>> - "typedef unsigned long long __u64;" from /usr/include/asm-generic/int-ll64.h
>>
>> uint64_t is unsigned long on x86-64 and gcc complains when using %llu
>> on such a type, so using a cast to u64 forces using PRIu64 too.
>>
>> Nevertheless "(__u64)" is shorter than "(unsigned long long)" and
>> seems to work fine in my quick tests because it is always unsigned
>> long long (on both x86-32 and x86-64). Would you prefer to use this
>> cast?
>
> Hello,
> After the question I had on the 4th revision of this patch, I have not
> received any reply or comment for three weeks. What should I do in
> order to get this merged?
>
> Thanks,
> Nicolas

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v4 1/1] x86, relocs: add printf attribute to die()
  2017-05-17  6:37       ` Nicolas Iooss
@ 2017-05-27 19:28         ` Andy Shevchenko
  0 siblings, 0 replies; 6+ messages in thread
From: Andy Shevchenko @ 2017-05-27 19:28 UTC (permalink / raw)
  To: Nicolas Iooss
  Cc: Ingo Molnar, Thomas Gleixner, Ingo Molnar, H. Peter Anvin, x86,
	linux-kernel

On Wed, May 17, 2017 at 9:37 AM, Nicolas Iooss
<nicolas.iooss_linux@m4x.org> wrote:
> Hello,
>
> The patch I sent a few months ago still applies cleanly on top of
> 4.12-rc1. What should I do in order to get it merged in 4.13?
>
> In case you no longer have my initial email, the patch has been
> archived in https://patchwork.kernel.org/patch/9604651/ .

Avoid top postings, please.

Looking into patch I see the following
1) the constify part is better to be a separate patch;
2) shouldn't be specifier '%ju' applied?

>>>> Isn't "(u64)" shorter to write?
>>>
>>> u64 does not seem to be defined in this file right now. Adding
>>> "#include <linux/types.h>" defines u64 and __u64 in the following way:
>>> - "typedef uint64_t u64;" from tools/include/linux/types.h
>>> - "typedef unsigned long long __u64;" from /usr/include/asm-generic/int-ll64.h
>>>
>>> uint64_t is unsigned long on x86-64 and gcc complains when using %llu
>>> on such a type, so using a cast to u64 forces using PRIu64 too.

-- 
With Best Regards,
Andy Shevchenko

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2017-05-27 19:28 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-03-05 14:12 [PATCH v4 1/1] x86, relocs: add printf attribute to die() Nicolas Iooss
2017-03-07  9:16 ` Ingo Molnar
2017-03-07 12:37   ` Nicolas Iooss
2017-03-28 21:06     ` Nicolas Iooss
2017-05-17  6:37       ` Nicolas Iooss
2017-05-27 19:28         ` Andy Shevchenko

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