Re: [PATCH bpf-next v3 4/5] bpf, x86: Add jit support for private stack

[Yonghong Song <yonghong.song@linux.dev>]

On 9/29/24 1:31 AM, kernel test robot wrote:
> Hi Yonghong,
>
> kernel test robot noticed the following build warnings:
>
> [auto build test WARNING on bpf-next/master]
>
> url:    https://github.com/intel-lab-lkp/linux/commits/Yonghong-Song/bpf-Allow-each-subprog-having-stack-size-of-512-bytes/20240927-074744
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
> patch link:    https://lore.kernel.org/r/20240926234526.1770736-1-yonghong.song%40linux.dev
> patch subject: [PATCH bpf-next v3 4/5] bpf, x86: Add jit support for private stack
> config: x86_64-randconfig-122-20240929 (https://download.01.org/0day-ci/archive/20240929/202409291637.cuQ0jRdD-lkp@intel.com/config)
> compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240929/202409291637.cuQ0jRdD-lkp@intel.com/reproduce)
>
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202409291637.cuQ0jRdD-lkp@intel.com/
>
> sparse warnings: (new ones prefixed by >>)
>>> arch/x86/net/bpf_jit_comp.c:1503:47: sparse: sparse: incorrect type in argument 2 (different address spaces) @@     expected void *private_frame_ptr @@     got void [noderef] __percpu *[assigned] private_frame_ptr @@
>     arch/x86/net/bpf_jit_comp.c:1503:47: sparse:     expected void *private_frame_ptr
>     arch/x86/net/bpf_jit_comp.c:1503:47: sparse:     got void [noderef] __percpu *[assigned] private_frame_ptr

Okay, will make the change by adding __percpu to furnction parameter type.

>
> vim +1503 arch/x86/net/bpf_jit_comp.c
>
>    1442	
>    1443	#define __LOAD_TCC_PTR(off)			\
>    1444		EMIT3_off32(0x48, 0x8B, 0x85, off)
>    1445	/* mov rax, qword ptr [rbp - rounded_stack_depth - 16] */
>    1446	#define LOAD_TAIL_CALL_CNT_PTR(stack)				\
>    1447		__LOAD_TCC_PTR(BPF_TAIL_CALL_CNT_PTR_STACK_OFF(stack))
>    1448	
[...]