Re: [PATCH bpf-next v2 14/21] bpf: Add tracing_multi link info support for bpf progs

[kernel test robot <lkp@intel.com>]

Hi Leon,

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/Leon-Hwang/bpf-Initialize-ftrace_managed-in-bpf_trampoline_get/20261012-234003
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
patch link:    https://lore.kernel.org/r/20261012154024.29423-15-leon.hwang%40linux.dev
patch subject: [PATCH bpf-next v2 14/21] bpf: Add tracing_multi link info support for bpf progs
config: i386-randconfig-1011-20261013 (https://download.01.org/0day-ci/archive/20261015/202610151004.s3b0Ih11-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20261015/202610151004.s3b0Ih11-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/202610151004.s3b0Ih11-lkp@intel.com/

All warnings (new ones prefixed by >>):

   kernel/trace/bpf_trace.c: In function 'bpf_tracing_multi_link_fill_link_info':
>> kernel/trace/bpf_trace.c:3755:32: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
    3755 |                         addr = (u64) mnode->trampoline->func.addr;
         |                                ^


vim +3755 kernel/trace/bpf_trace.c

  3708	
  3709	static int bpf_tracing_multi_link_fill_link_info(const struct bpf_link *link,
  3710							 struct bpf_link_info *info)
  3711	{
  3712		u32 __user *fids = u64_to_user_ptr(info->tracing_multi.func_btf_ids);
  3713		u64 __user *ucookies = u64_to_user_ptr(info->tracing_multi.cookies);
  3714		u64 __user *uaddrs = u64_to_user_ptr(info->tracing_multi.addrs);
  3715		u32 __user *uids = u64_to_user_ptr(info->tracing_multi.ids);
  3716		struct bpf_tracing_multi_link *tr_link;
  3717		u32 ucount = info->tracing_multi.count;
  3718		bool has_cookies, show_addrs, has_progs;
  3719		int err = 0;
  3720	
  3721		if ((uids || ucookies || uaddrs || fids) && !ucount)
  3722			return -EINVAL;
  3723	
  3724		tr_link = container_of(link, struct bpf_tracing_multi_link, link);
  3725	
  3726		info->tracing_multi.attach_type = tr_link->link.attach_type;
  3727		info->tracing_multi.count = tr_link->nodes_cnt;
  3728		info->tracing_multi.btf_obj_id = btf_obj_id(tr_link->link.prog->aux->attach_btf);
  3729		has_progs = !!tr_link->tgt_progs;
  3730		info->tracing_multi.flags = has_progs ? BPF_F_TRACING_MULTI_TGT_PROGS : 0;
  3731	
  3732		if (!uids && !ucookies && !uaddrs && !fids)
  3733			return 0;
  3734		if (has_progs != !!fids)
  3735			return -EINVAL;
  3736	
  3737		if (ucount < tr_link->nodes_cnt)
  3738			err = -ENOSPC;
  3739		else
  3740			ucount = tr_link->nodes_cnt;
  3741	
  3742		has_cookies = !!tr_link->cookies;
  3743		show_addrs = kallsyms_show_value(current_cred());
  3744	
  3745		for (int i = 0; i < ucount; i++) {
  3746			struct bpf_tracing_multi_node *mnode = &tr_link->nodes[i];
  3747			u32 prog_id, btf_id;
  3748			u64 addr, cookie;
  3749	
  3750			bpf_trampoline_unpack_key(mnode->trampoline->key, &prog_id, &btf_id);
  3751	
  3752			if (!show_addrs)
  3753				addr = 0;
  3754			else if (has_progs)
> 3755				addr = (u64) mnode->trampoline->func.addr;
  3756			else
  3757				addr = mnode->trampoline->ip;
  3758			cookie = has_cookies ? tr_link->cookies[i] : 0;
  3759	
  3760			if (uids && put_user(has_progs ? prog_id : btf_id, uids + i))
  3761				return -EFAULT;
  3762			if (uaddrs && put_user(addr, uaddrs + i))
  3763				return -EFAULT;
  3764			if (ucookies && put_user(cookie, ucookies + i))
  3765				return -EFAULT;
  3766			if (has_progs && put_user((u32) mnode->trampoline->key, fids + i))
  3767				return -EFAULT;
  3768	
  3769			cond_resched();
  3770		}
  3771	
  3772		return err;
  3773	}
  3774	

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki