* Re: [linux-next:master 5519/11156] kernel/bpf/bpf_struct_ops.c:247:16: warning: bitwise operation between different enumeration types ('enum bpf_type_flag' and 'enum bpf_reg_type')
[not found] ` <CAFVMQ6QYvHfc_=cpOddWgoWDTRt3GHG5+LLB3NoFFRRiCMWDLw@mail.gmail.com>
@ 2024-03-01 18:25 ` Kui-Feng Lee
2024-03-01 18:27 ` Alexei Starovoitov
0 siblings, 1 reply; 3+ messages in thread
From: Kui-Feng Lee @ 2024-03-01 18:25 UTC (permalink / raw)
To: Thinker Li, kernel test robot
Cc: oe-kbuild-all, Linux Memory Management List, Martin KaFai Lau,
bpf
For BPF,
We have a lot of code mixing bpf_type_flag and bpf_reg_type in bpf.
They cause the warning messages described in the message following.
Do we want to fix them all, or keep them as they are?
They can be fixed by merging two enum types or casting here and there if
we want. Any other idea?
On 2/29/24 13:07, Thinker Li wrote:
> I am checking it.
>
> On Thu, Feb 29, 2024 at 12:32 PM kernel test robot <lkp@intel.com
> <mailto:lkp@intel.com>> wrote:
>
> tree:
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
> <https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git> master
> head: f303a3e2bcfba900efb5aee55236d17030e9f882
> commit: 1611603537a4b88cec7993f32b70c03113801a46 [5519/11156] bpf:
> Create argument information for nullable arguments.
> config: s390-randconfig-r133-20240229
> (https://download.01.org/0day-ci/archive/20240301/202403010423.0vNdUDBW-lkp@intel.com/config <https://download.01.org/0day-ci/archive/20240301/202403010423.0vNdUDBW-lkp@intel.com/config>)
> compiler: clang version 19.0.0git
> (https://github.com/llvm/llvm-project
> <https://github.com/llvm/llvm-project>
> edd4aee4dd9b5b98b2576a6f783e4086173d902a)
> reproduce:
> (https://download.01.org/0day-ci/archive/20240301/202403010423.0vNdUDBW-lkp@intel.com/reproduce <https://download.01.org/0day-ci/archive/20240301/202403010423.0vNdUDBW-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 <mailto:lkp@intel.com>>
> | Closes:
> https://lore.kernel.org/oe-kbuild-all/202403010423.0vNdUDBW-lkp@intel.com/ <https://lore.kernel.org/oe-kbuild-all/202403010423.0vNdUDBW-lkp@intel.com/>
>
> All warnings (new ones prefixed by >>):
>
> | ~~~~~~~~~~~~~~
> ^ ~~~~~~~~~~~~~~~~~
> include/linux/bpf.h:778:47: warning: bitwise operation between
> different enumeration types ('enum bpf_type_flag' and 'enum
> bpf_return_type') [-Wenum-enum-conversion]
> 778 | RET_PTR_TO_TCP_SOCK_OR_NULL = PTR_MAYBE_NULL
> | RET_PTR_TO_TCP_SOCK,
> | ~~~~~~~~~~~~~~
> ^ ~~~~~~~~~~~~~~~~~~~
> include/linux/bpf.h:779:50: warning: bitwise operation between
> different enumeration types ('enum bpf_type_flag' and 'enum
> bpf_return_type') [-Wenum-enum-conversion]
> 779 | RET_PTR_TO_SOCK_COMMON_OR_NULL = PTR_MAYBE_NULL
> | RET_PTR_TO_SOCK_COMMON,
> | ~~~~~~~~~~~~~~
> ^ ~~~~~~~~~~~~~~~~~~~~~~
> include/linux/bpf.h:781:49: warning: bitwise operation between
> different enumeration types ('enum bpf_type_flag' and 'enum
> bpf_return_type') [-Wenum-enum-conversion]
> 781 | RET_PTR_TO_DYNPTR_MEM_OR_NULL = PTR_MAYBE_NULL
> | RET_PTR_TO_MEM,
> | ~~~~~~~~~~~~~~
> ^ ~~~~~~~~~~~~~~
> include/linux/bpf.h:782:45: warning: bitwise operation between
> different enumeration types ('enum bpf_type_flag' and 'enum
> bpf_return_type') [-Wenum-enum-conversion]
> 782 | RET_PTR_TO_BTF_ID_OR_NULL = PTR_MAYBE_NULL
> | RET_PTR_TO_BTF_ID,
> | ~~~~~~~~~~~~~~
> ^ ~~~~~~~~~~~~~~~~~
> include/linux/bpf.h:783:43: warning: bitwise operation between
> different enumeration types ('enum bpf_type_flag' and 'enum
> bpf_return_type') [-Wenum-enum-conversion]
> 783 | RET_PTR_TO_BTF_ID_TRUSTED = PTR_TRUSTED
> | RET_PTR_TO_BTF_ID,
> | ~~~~~~~~~~~
> ^ ~~~~~~~~~~~~~~~~~
> include/linux/bpf.h:894:44: warning: bitwise operation between
> different enumeration types ('enum bpf_type_flag' and 'enum
> bpf_reg_type') [-Wenum-enum-conversion]
> 894 | PTR_TO_MAP_VALUE_OR_NULL = PTR_MAYBE_NULL
> | PTR_TO_MAP_VALUE,
> | ~~~~~~~~~~~~~~
> ^ ~~~~~~~~~~~~~~~~
> include/linux/bpf.h:895:42: warning: bitwise operation between
> different enumeration types ('enum bpf_type_flag' and 'enum
> bpf_reg_type') [-Wenum-enum-conversion]
> 895 | PTR_TO_SOCKET_OR_NULL = PTR_MAYBE_NULL
> | PTR_TO_SOCKET,
> | ~~~~~~~~~~~~~~
> ^ ~~~~~~~~~~~~~
> include/linux/bpf.h:896:46: warning: bitwise operation between
> different enumeration types ('enum bpf_type_flag' and 'enum
> bpf_reg_type') [-Wenum-enum-conversion]
> 896 | PTR_TO_SOCK_COMMON_OR_NULL = PTR_MAYBE_NULL
> | PTR_TO_SOCK_COMMON,
> | ~~~~~~~~~~~~~~
> ^ ~~~~~~~~~~~~~~~~~~
> include/linux/bpf.h:897:44: warning: bitwise operation between
> different enumeration types ('enum bpf_type_flag' and 'enum
> bpf_reg_type') [-Wenum-enum-conversion]
> 897 | PTR_TO_TCP_SOCK_OR_NULL = PTR_MAYBE_NULL
> | PTR_TO_TCP_SOCK,
> | ~~~~~~~~~~~~~~
> ^ ~~~~~~~~~~~~~~~
> include/linux/bpf.h:898:42: warning: bitwise operation between
> different enumeration types ('enum bpf_type_flag' and 'enum
> bpf_reg_type') [-Wenum-enum-conversion]
> 898 | PTR_TO_BTF_ID_OR_NULL = PTR_MAYBE_NULL
> | PTR_TO_BTF_ID,
> | ~~~~~~~~~~~~~~
> ^ ~~~~~~~~~~~~~
> In file included from kernel/bpf/bpf_struct_ops.c:5:
> In file included from include/linux/bpf_verifier.h:9:
> In file included from include/linux/filter.h:12:
> In file included from include/linux/skbuff.h:28:
> In file included from include/linux/dma-mapping.h:11:
> In file included from include/linux/scatterlist.h:9:
> In file included from arch/s390/include/asm/io.h:78:
> include/asm-generic/io.h:547:31: warning: performing pointer
> arithmetic on a null pointer has undefined behavior
> [-Wnull-pointer-arithmetic]
> 547 | val = __raw_readb(PCI_IOBASE + addr);
> | ~~~~~~~~~~ ^
> include/asm-generic/io.h:560:61: warning: performing pointer
> arithmetic on a null pointer has undefined behavior
> [-Wnull-pointer-arithmetic]
> 560 | val = __le16_to_cpu((__le16
> __force)__raw_readw(PCI_IOBASE + addr));
> |
> ~~~~~~~~~~ ^
> include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded
> from macro '__le16_to_cpu'
> 37 | #define __le16_to_cpu(x) __swab16((__force
> __u16)(__le16)(x))
> | ^
> include/uapi/linux/swab.h:102:54: note: expanded from macro
> '__swab16'
> 102 | #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
> | ^
> In file included from kernel/bpf/bpf_struct_ops.c:5:
> In file included from include/linux/bpf_verifier.h:9:
> In file included from include/linux/filter.h:12:
> In file included from include/linux/skbuff.h:28:
> In file included from include/linux/dma-mapping.h:11:
> In file included from include/linux/scatterlist.h:9:
> In file included from arch/s390/include/asm/io.h:78:
> include/asm-generic/io.h:573:61: warning: performing pointer
> arithmetic on a null pointer has undefined behavior
> [-Wnull-pointer-arithmetic]
> 573 | val = __le32_to_cpu((__le32
> __force)__raw_readl(PCI_IOBASE + addr));
> |
> ~~~~~~~~~~ ^
> include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded
> from macro '__le32_to_cpu'
> 35 | #define __le32_to_cpu(x) __swab32((__force
> __u32)(__le32)(x))
> | ^
> include/uapi/linux/swab.h:115:54: note: expanded from macro
> '__swab32'
> 115 | #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
> | ^
> In file included from kernel/bpf/bpf_struct_ops.c:5:
> In file included from include/linux/bpf_verifier.h:9:
> In file included from include/linux/filter.h:12:
> In file included from include/linux/skbuff.h:28:
> In file included from include/linux/dma-mapping.h:11:
> In file included from include/linux/scatterlist.h:9:
> In file included from arch/s390/include/asm/io.h:78:
> include/asm-generic/io.h:584:33: warning: performing pointer
> arithmetic on a null pointer has undefined behavior
> [-Wnull-pointer-arithmetic]
> 584 | __raw_writeb(value, PCI_IOBASE + addr);
> | ~~~~~~~~~~ ^
> include/asm-generic/io.h:594:59: warning: performing pointer
> arithmetic on a null pointer has undefined behavior
> [-Wnull-pointer-arithmetic]
> 594 | __raw_writew((u16 __force)cpu_to_le16(value),
> PCI_IOBASE + addr);
> |
> ~~~~~~~~~~ ^
> include/asm-generic/io.h:604:59: warning: performing pointer
> arithmetic on a null pointer has undefined behavior
> [-Wnull-pointer-arithmetic]
> 604 | __raw_writel((u32 __force)cpu_to_le32(value),
> PCI_IOBASE + addr);
> |
> ~~~~~~~~~~ ^
> include/asm-generic/io.h:692:20: warning: performing pointer
> arithmetic on a null pointer has undefined behavior
> [-Wnull-pointer-arithmetic]
> 692 | readsb(PCI_IOBASE + addr, buffer, count);
> | ~~~~~~~~~~ ^
> include/asm-generic/io.h:700:20: warning: performing pointer
> arithmetic on a null pointer has undefined behavior
> [-Wnull-pointer-arithmetic]
> 700 | readsw(PCI_IOBASE + addr, buffer, count);
> | ~~~~~~~~~~ ^
> include/asm-generic/io.h:708:20: warning: performing pointer
> arithmetic on a null pointer has undefined behavior
> [-Wnull-pointer-arithmetic]
> 708 | readsl(PCI_IOBASE + addr, buffer, count);
> | ~~~~~~~~~~ ^
> include/asm-generic/io.h:717:21: warning: performing pointer
> arithmetic on a null pointer has undefined behavior
> [-Wnull-pointer-arithmetic]
> 717 | writesb(PCI_IOBASE + addr, buffer, count);
> | ~~~~~~~~~~ ^
> include/asm-generic/io.h:726:21: warning: performing pointer
> arithmetic on a null pointer has undefined behavior
> [-Wnull-pointer-arithmetic]
> 726 | writesw(PCI_IOBASE + addr, buffer, count);
> | ~~~~~~~~~~ ^
> include/asm-generic/io.h:735:21: warning: performing pointer
> arithmetic on a null pointer has undefined behavior
> [-Wnull-pointer-arithmetic]
> 735 | writesl(PCI_IOBASE + addr, buffer, count);
> | ~~~~~~~~~~ ^
> >> kernel/bpf/bpf_struct_ops.c:247:16: warning: bitwise operation
> between different enumeration types ('enum bpf_type_flag' and 'enum
> bpf_reg_type') [-Wenum-enum-conversion]
> 247 | PTR_TRUSTED | PTR_TO_BTF_ID |
> PTR_MAYBE_NULL;
> | ~~~~~~~~~~~ ^ ~~~~~~~~~~~~~
> 38 warnings generated.
>
>
> vim +247 kernel/bpf/bpf_struct_ops.c
>
> 153
> 154 /* Prepare argument info for every nullable argument of a
> member of a
> 155 * struct_ops type.
> 156 *
> 157 * Initialize a struct bpf_struct_ops_arg_info according to
> type info of
> 158 * the arguments of a stub function. (Check kCFI for more
> information about
> 159 * stub functions.)
> 160 *
> 161 * Each member in the struct_ops type has a struct
> bpf_struct_ops_arg_info
> 162 * to provide an array of struct bpf_ctx_arg_aux, which in
> turn provides
> 163 * the information that used by the verifier to check the
> arguments of the
> 164 * BPF struct_ops program assigned to the member. Here, we
> only care about
> 165 * the arguments that are marked as __nullable.
> 166 *
> 167 * The array of struct bpf_ctx_arg_aux is eventually
> assigned to
> 168 * prog->aux->ctx_arg_info of BPF struct_ops programs and
> passed to the
> 169 * verifier. (See check_struct_ops_btf_id())
> 170 *
> 171 * arg_info->info will be the list of struct
> bpf_ctx_arg_aux if success. If
> 172 * fails, it will be kept untouched.
> 173 */
> 174 static int prepare_arg_info(struct btf *btf,
> 175 const char *st_ops_name,
> 176 const char *member_name,
> 177 const struct btf_type *func_proto,
> 178 struct bpf_struct_ops_arg_info
> *arg_info)
> 179 {
> 180 const struct btf_type *stub_func_proto, *pointed_type;
> 181 const struct btf_param *stub_args, *args;
> 182 struct bpf_ctx_arg_aux *info, *info_buf;
> 183 u32 nargs, arg_no, info_cnt = 0;
> 184 u32 arg_btf_id;
> 185 int offset;
> 186
> 187 stub_func_proto = find_stub_func_proto(btf,
> st_ops_name, member_name);
> 188 if (!stub_func_proto)
> 189 return 0;
> 190
> 191 /* Check if the number of arguments of the stub
> function is the same
> 192 * as the number of arguments of the function pointer.
> 193 */
> 194 nargs = btf_type_vlen(func_proto);
> 195 if (nargs != btf_type_vlen(stub_func_proto)) {
> 196 pr_warn("the number of arguments of the
> stub function %s__%s does not match the number of arguments of the
> member %s of struct %s\n",
> 197 st_ops_name, member_name,
> member_name, st_ops_name);
> 198 return -EINVAL;
> 199 }
> 200
> 201 if (!nargs)
> 202 return 0;
> 203
> 204 args = btf_params(func_proto);
> 205 stub_args = btf_params(stub_func_proto);
> 206
> 207 info_buf = kcalloc(nargs, sizeof(*info_buf),
> GFP_KERNEL);
> 208 if (!info_buf)
> 209 return -ENOMEM;
> 210
> 211 /* Prepare info for every nullable argument */
> 212 info = info_buf;
> 213 for (arg_no = 0; arg_no < nargs; arg_no++) {
> 214 /* Skip arguments that is not suffixed with
> 215 * "__nullable".
> 216 */
> 217 if (!btf_param_match_suffix(btf,
> &stub_args[arg_no],
> 218 MAYBE_NULL_SUFFIX))
> 219 continue;
> 220
> 221 /* Should be a pointer to struct */
> 222 pointed_type = btf_type_resolve_ptr(btf,
> 223
> args[arg_no].type,
> 224
> &arg_btf_id);
> 225 if (!pointed_type ||
> 226 !btf_type_is_struct(pointed_type)) {
> 227 pr_warn("stub function %s__%s has
> %s tagging to an unsupported type\n",
> 228 st_ops_name, member_name,
> MAYBE_NULL_SUFFIX);
> 229 goto err_out;
> 230 }
> 231
> 232 offset = btf_ctx_arg_offset(btf,
> func_proto, arg_no);
> 233 if (offset < 0) {
> 234 pr_warn("stub function %s__%s has
> an invalid trampoline ctx offset for arg#%u\n",
> 235 st_ops_name, member_name,
> arg_no);
> 236 goto err_out;
> 237 }
> 238
> 239 if (args[arg_no].type !=
> stub_args[arg_no].type) {
> 240 pr_warn("arg#%u type in stub
> function %s__%s does not match with its original func_proto\n",
> 241 arg_no, st_ops_name,
> member_name);
> 242 goto err_out;
> 243 }
> 244
> 245 /* Fill the information of the new argument */
> 246 info->reg_type =
> > 247 PTR_TRUSTED | PTR_TO_BTF_ID |
> PTR_MAYBE_NULL;
> 248 info->btf_id = arg_btf_id;
> 249 info->btf = btf;
> 250 info->offset = offset;
> 251
> 252 info++;
> 253 info_cnt++;
> 254 }
> 255
> 256 if (info_cnt) {
> 257 arg_info->info = info_buf;
> 258 arg_info->cnt = info_cnt;
> 259 } else {
> 260 kfree(info_buf);
> 261 }
> 262
> 263 return 0;
> 264
> 265 err_out:
> 266 kfree(info_buf);
> 267
> 268 return -EINVAL;
> 269 }
> 270
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki
> <https://github.com/intel/lkp-tests/wiki>
>
^ permalink raw reply [flat|nested] 3+ messages in thread