[PATCH bpf-next 7/8] selftests/bpf: Verify zero-extension behavior in load-acquire tests

[Pu Lehui]

On 2025/4/30 8:51, Peilin Ye wrote:
> Verify that 8-, 16- and 32-bit load-acquires are zero-extending by using
> immediate values with their highest bit set.  Do the same for the 64-bit
> variant to keep the style consistent.
> 
> Signed-off-by: Peilin Ye <yepeilin at google.com>
> ---
>   tools/testing/selftests/bpf/progs/verifier_load_acquire.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/testing/selftests/bpf/progs/verifier_load_acquire.c b/tools/testing/selftests/bpf/progs/verifier_load_acquire.c
> index a696ab84bfd6..74f4f19c10b8 100644
> --- a/tools/testing/selftests/bpf/progs/verifier_load_acquire.c
> +++ b/tools/testing/selftests/bpf/progs/verifier_load_acquire.c
> @@ -15,7 +15,7 @@ __naked void load_acquire_8(void)
>   {
>   	asm volatile (
>   	"r0 = 0;"
> -	"w1 = 0x12;"
> +	"w1 = 0xfe;"
>   	"*(u8 *)(r10 - 1) = w1;"
>   	".8byte %[load_acquire_insn];" // w2 = load_acquire((u8 *)(r10 - 1));
>   	"if r2 == r1 goto 1f;"
> @@ -35,7 +35,7 @@ __naked void load_acquire_16(void)
>   {
>   	asm volatile (
>   	"r0 = 0;"
> -	"w1 = 0x1234;"
> +	"w1 = 0xfedc;"
>   	"*(u16 *)(r10 - 2) = w1;"
>   	".8byte %[load_acquire_insn];" // w2 = load_acquire((u16 *)(r10 - 2));
>   	"if r2 == r1 goto 1f;"
> @@ -55,7 +55,7 @@ __naked void load_acquire_32(void)
>   {
>   	asm volatile (
>   	"r0 = 0;"
> -	"w1 = 0x12345678;"
> +	"w1 = 0xfedcba09;"
>   	"*(u32 *)(r10 - 4) = w1;"
>   	".8byte %[load_acquire_insn];" // w2 = load_acquire((u32 *)(r10 - 4));
>   	"if r2 == r1 goto 1f;"
> @@ -75,7 +75,7 @@ __naked void load_acquire_64(void)
>   {
>   	asm volatile (
>   	"r0 = 0;"
> -	"r1 = 0x1234567890abcdef ll;"
> +	"r1 = 0xfedcba0987654321 ll;"
>   	"*(u64 *)(r10 - 8) = r1;"
>   	".8byte %[load_acquire_insn];" // r2 = load_acquire((u64 *)(r10 - 8));
>   	"if r2 == r1 goto 1f;"
Reviewed-by: Pu Lehui <pulehui at huawei.com>