Re: [PATCH v3 1/3] x86/mce: Use is_copy_from_user() to determine copy-from-user context

kernel test robot
2025-03-07T03:40:22Z

Hi Shuai,

kernel test robot noticed the following build errors:

[auto build test ERROR on akpm-mm/mm-everything]

url: https://github.com/intel-lab-lkp/linux/commits/Shuai-Xue/x86-mce-Use-is_copy_from_user-to-determine-copy-from-user-context/20250306-101505
base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link: https://lore.kernel.org/r/20250306021031.5538-2-xueshuai%40linux.alibaba.com
patch subject: [PATCH v3 1/3] x86/mce: Use is_copy_from_user() to determine copy-from-user context
config: i386-buildonly-randconfig-005-20250307 (https://download.01.org/0day-ci/archive/20250307/202503071115.uNkoVksh-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/20250307/202503071115.uNkoVksh-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/202503071115.uNkoVksh-lkp@intel.com/

All errors (new ones prefixed by >>):

arch/x86/kernel/cpu/mce/severity.c: In function 'error_context':
>> arch/x86/kernel/cpu/mce/severity.c:305:39: error: expected ';' before '}' token
305 | return IN_KERNEL_RECOV
| ^
| ;
306 | }
| ~

vim +305 arch/x86/kernel/cpu/mce/severity.c

274
275 /*
276 * If mcgstatus indicated that ip/cs on the stack were
277 * no good, then "m->cs" will be zero and we will have
278 * to assume the worst case (IN_KERNEL) as we actually
279 * have no idea what we were executing when the machine
280 * check hit.
281 * If we do have a good "m->cs" (or a faked one in the
282 * case we were executing in VM86 mode) we can use it to
283 * distinguish an exception taken in user from from one
284 * taken in the kernel.
285 */
286 static noinstr int error_context(struct mce *m, struct pt_regs *regs)
287 {
288 int fixup_type;
289 bool copy_user;
290
291 if ((m->cs & 3) == 3)
292 return IN_USER;
293
294 if (!mc_recoverable(m->mcgstatus))
295 return IN_KERNEL;
296
297 /* Allow instrumentation around external facilities usage. */
298 instrumentation_begin();
299 fixup_type = ex_get_fixup_type(m->ip);
300 copy_user = is_copy_from_user(regs);
301 instrumentation_end();
302
303 if (copy_user) {
304 m->kflags |= MCE_IN_KERNEL_COPYIN | MCE_IN_KERNEL_COPYIN;
> 305 return IN_KERNEL_RECOV
306 }
307
308 switch (fixup_type) {
309 case EX_TYPE_FAULT_MCE_SAFE:
310 case EX_TYPE_DEFAULT_MCE_SAFE:
311 m->kflags |= MCE_IN_KERNEL_RECOV;
312 return IN_KERNEL_RECOV;
313
314 default:
315 return IN_KERNEL;
316 }
317 }
318

--
0-DAY CI Kernel Test Service