tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: 8936cec5cb6e27649b86fabf383d7ce4113bba49 commit: 599382062e7b91fb049e339db93c3a0b840d2b6e [4579/4901] x86/mce: add EX_TYPE_EFAULT_REG as in-kernel recovery context to fix copy-from-user operations regression config: x86_64-buildonly-randconfig-004-20250220 (https://download.01.org/0day-ci/archive/20250220/202502201215.ZkIMdQVr-lkp@xxxxxxxxx/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/20250220/202502201215.ZkIMdQVr-lkp@xxxxxxxxx/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@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202502201215.ZkIMdQVr-lkp@xxxxxxxxx/ Note: the linux-next/master HEAD 8936cec5cb6e27649b86fabf383d7ce4113bba49 builds fine. It may have been fixed somewhere. All errors (new ones prefixed by >>): arch/x86/kernel/cpu/mce/severity.c: In function 'error_context': >> arch/x86/kernel/cpu/mce/severity.c:305:22: error: implicit declaration of function 'FIELD_GET' [-Werror=implicit-function-declaration] 305 | fixup_type = FIELD_GET(EX_DATA_TYPE_MASK, e->data); | ^~~~~~~~~ cc1: some warnings being treated as errors vim +/FIELD_GET +305 arch/x86/kernel/cpu/mce/severity.c 275 276 /* 277 * If mcgstatus indicated that ip/cs on the stack were 278 * no good, then "m->cs" will be zero and we will have 279 * to assume the worst case (IN_KERNEL) as we actually 280 * have no idea what we were executing when the machine 281 * check hit. 282 * If we do have a good "m->cs" (or a faked one in the 283 * case we were executing in VM86 mode) we can use it to 284 * distinguish an exception taken in user from from one 285 * taken in the kernel. 286 */ 287 static noinstr int error_context(struct mce *m, struct pt_regs *regs) 288 { 289 const struct exception_table_entry *e; 290 int fixup_type, imm; 291 bool copy_user; 292 293 if ((m->cs & 3) == 3) 294 return IN_USER; 295 296 if (!mc_recoverable(m->mcgstatus)) 297 return IN_KERNEL; 298 299 e = search_exception_tables(m->ip); 300 if (!e) 301 return IN_KERNEL; 302 303 /* Allow instrumentation around external facilities usage. */ 304 instrumentation_begin(); > 305 fixup_type = FIELD_GET(EX_DATA_TYPE_MASK, e->data); 306 imm = FIELD_GET(EX_DATA_IMM_MASK, e->data); 307 copy_user = is_copy_from_user(regs); 308 instrumentation_end(); 309 310 switch (fixup_type) { 311 case EX_TYPE_UACCESS: 312 if (!copy_user) 313 return IN_KERNEL; 314 m->kflags |= MCE_IN_KERNEL_COPYIN | MCE_IN_KERNEL_RECOV; 315 return IN_KERNEL_RECOV; 316 case EX_TYPE_IMM_REG: 317 if (!copy_user || imm != -EFAULT) 318 return IN_KERNEL; 319 m->kflags |= MCE_IN_KERNEL_COPYIN | MCE_IN_KERNEL_RECOV; 320 return IN_KERNEL_RECOV; 321 case EX_TYPE_FAULT_MCE_SAFE: 322 case EX_TYPE_DEFAULT_MCE_SAFE: 323 m->kflags |= MCE_IN_KERNEL_RECOV; 324 return IN_KERNEL_RECOV; 325 326 default: 327 return IN_KERNEL; 328 } 329 } 330 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
