[selftests/bpf QUESTION] What is the proper way to fix the build error

[selftests/bpf QUESTION] What is the proper way to fix the build error

[Tiezhu Yang]

Hi,

When compiling tools/testing/selftests/bpf, there is a build error:

   CLNG-BPF [test_progs] verifier_global_ptr_args.bpf.o
progs/verifier_global_ptr_args.c:228:5: error: redefinition of 'off' as 
different kind of symbol
   228 | u32 off;
       |     ^
/home/fedora/newfixbpf.git/tools/testing/selftests/bpf/tools/include/vmlinux.h:21409:2: 
note: previous definition is here
  21409 |         off = 0,
        |         ^
1 error generated.

tools/testing/selftests/bpf/tools/include/vmlinux.h:21409

enum i40e_ptp_gpio_pin_state {
         end = -2,
         invalid = -1,
         off = 0,
         in_A = 1,
         in_B = 2,
         out_A = 3,
         out_B = 4,
};

The previous definition of "off" is in
drivers/net/ethernet/intel/i40e/i40e_ptp.c:

enum i40e_ptp_gpio_pin_state {
	end = -2,
	invalid,
	off,
	in_A,
	in_B,
	out_A,
	out_B,
};

CONFIG_I40E is set in the defconfig file to build i40e_ptp.c after the
commit 032676ff8217 (LoongArch: Update Loongson-3 default config file)
in 6.18-rc1.

What is the proper way to fix the build error?
(1) just disable CONFIG_I40E (CONFIG_I40E=n), then no "off" in vmlinux.h
(2) set it as a module (CONFIG_I40E=m), then no "off" in vmlinux.h
(3) modify the variable name "off" in verifier_global_ptr_args.c

Thanks,
Tiezhu

Re: [selftests/bpf QUESTION] What is the proper way to fix the build error

[Yonghong Song]

On 10/17/25 3:05 AM, Tiezhu Yang wrote:
> Hi,
>
> When compiling tools/testing/selftests/bpf, there is a build error:
>
>   CLNG-BPF [test_progs] verifier_global_ptr_args.bpf.o
> progs/verifier_global_ptr_args.c:228:5: error: redefinition of 'off' 
> as different kind of symbol
>   228 | u32 off;
>       |     ^
> /home/fedora/newfixbpf.git/tools/testing/selftests/bpf/tools/include/vmlinux.h:21409:2: 
> note: previous definition is here
>  21409 |         off = 0,
>        |         ^
> 1 error generated.
>
> tools/testing/selftests/bpf/tools/include/vmlinux.h:21409
>
> enum i40e_ptp_gpio_pin_state {
>         end = -2,
>         invalid = -1,
>         off = 0,
>         in_A = 1,
>         in_B = 2,
>         out_A = 3,
>         out_B = 4,
> };
>
> The previous definition of "off" is in
> drivers/net/ethernet/intel/i40e/i40e_ptp.c:
>
> enum i40e_ptp_gpio_pin_state {
>     end = -2,
>     invalid,
>     off,
>     in_A,
>     in_B,
>     out_A,
>     out_B,
> };
>
> CONFIG_I40E is set in the defconfig file to build i40e_ptp.c after the
> commit 032676ff8217 (LoongArch: Update Loongson-3 default config file)
> in 6.18-rc1.
>
> What is the proper way to fix the build error?
> (1) just disable CONFIG_I40E (CONFIG_I40E=n), then no "off" in vmlinux.h
> (2) set it as a module (CONFIG_I40E=m), then no "off" in vmlinux.h
> (3) modify the variable name "off" in verifier_global_ptr_args.c

I would recommend to rename 'off' in verifier_global_ptr_args.c to 'offset'.

>
> Thanks,
> Tiezhu
>
>

[PATCH] selftests/bpf: Fix redefinition of 'off' as different kind of symbol

[Brahmajit Das]

This fixes the following build error

   CLNG-BPF [test_progs] verifier_global_ptr_args.bpf.o
progs/verifier_global_ptr_args.c:228:5: error: redefinition of 'off' as
different kind of symbol
   228 | u32 off;
       |     ^

Suggested-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Brahmajit Das <listout@listout.xyz>
---
Please refer: https://lore.kernel.org/bpf/5ca1d6a6-5e5a-3485-d3cd-f9439612d1f3@loongson.cn/
---
 .../selftests/bpf/progs/verifier_global_ptr_args.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c b/tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c
index 6630a92b1b47..1204fbc58178 100644
--- a/tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c
+++ b/tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c
@@ -225,7 +225,7 @@ int trusted_to_untrusted(void *ctx)
 }
 
 char mem[16];
-u32 off;
+u32 offset;
 
 SEC("tp_btf/sys_enter")
 __success
@@ -240,9 +240,9 @@ int anything_to_untrusted(void *ctx)
 	/* scalar to untrusted */
 	subprog_untrusted(0);
 	/* variable offset to untrusted (map) */
-	subprog_untrusted((void *)mem + off);
+	subprog_untrusted((void *)mem + offset);
 	/* variable offset to untrusted (trusted) */
-	subprog_untrusted((void *)bpf_get_current_task_btf() + off);
+	subprog_untrusted((void *)bpf_get_current_task_btf() + offset);
 	return 0;
 }
 
@@ -298,12 +298,12 @@ int anything_to_untrusted_mem(void *ctx)
 	/* scalar to untrusted mem */
 	subprog_void_untrusted(0);
 	/* variable offset to untrusted mem (map) */
-	subprog_void_untrusted((void *)mem + off);
+	subprog_void_untrusted((void *)mem + offset);
 	/* variable offset to untrusted mem (trusted) */
-	subprog_void_untrusted(bpf_get_current_task_btf() + off);
+	subprog_void_untrusted(bpf_get_current_task_btf() + offset);
 	/* variable offset to untrusted char/enum (map) */
-	subprog_char_untrusted(mem + off);
-	subprog_enum_untrusted((void *)mem + off);
+	subprog_char_untrusted(mem + offset);
+	subprog_enum_untrusted((void *)mem + offset);
 	return 0;
 }
 
-- 
2.51.0

Re: [PATCH] selftests/bpf: Fix redefinition of 'off' as different kind of symbol

[Yonghong Song]

On 10/17/25 8:54 AM, Brahmajit Das wrote:
> This fixes the following build error
>
>     CLNG-BPF [test_progs] verifier_global_ptr_args.bpf.o
> progs/verifier_global_ptr_args.c:228:5: error: redefinition of 'off' as
> different kind of symbol
>     228 | u32 off;
>         |     ^
>
> Suggested-by: Yonghong Song <yonghong.song@linux.dev>
> Signed-off-by: Brahmajit Das <listout@listout.xyz>

Please add more context in the commit message about where the
redefinition of 'off' comes from.

Also, please replace [PATCH] to [PATCH bpf] so CI can do proper testing.
So in the next revision you can have [PATCH bpf v2].

With the changes in the above, you can carry my ack.

Acked-by: Yonghong Song <yonghong.song@linux.dev>

> ---
> Please refer: https://lore.kernel.org/bpf/5ca1d6a6-5e5a-3485-d3cd-f9439612d1f3@loongson.cn/
> ---
>   .../selftests/bpf/progs/verifier_global_ptr_args.c | 14 +++++++-------
>   1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c b/tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c
> index 6630a92b1b47..1204fbc58178 100644
> --- a/tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c
> +++ b/tools/testing/selftests/bpf/progs/verifier_global_ptr_args.c
> @@ -225,7 +225,7 @@ int trusted_to_untrusted(void *ctx)
>   }
>   
>   char mem[16];
> -u32 off;
> +u32 offset;

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