Hi Christophe, FYI, the error/warning still remains. tree: https://github.com/linuxppc/linux next-test head: 3ac6488df9160f52bbd8b8ec3387a53ac3d0f2eb commit: 627b72bee84d6652e0af26617e71ce2b3c18fcd5 [130/182] powerpc/signal32: Convert restore_[tm]_user_regs() to user access block config: powerpc-mpc8540_ads_defconfig (attached as .config) compiler: powerpc-linux-gcc (GCC) 9.3.0 reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://github.com/linuxppc/linux/commit/627b72bee84d6652e0af26617e71ce2b... git remote add linuxppc https://github.com/linuxppc/linux git fetch --no-tags linuxppc next-test git checkout 627b72bee84d6652e0af26617e71ce2b3c18fcd5 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): arch/powerpc/kernel/signal_32.c: In function 'restore_user_regs': 573 | ELF_NEVRREG * sizeof(u32)); | ^ In file included from include/linux/uaccess.h:11, from include/linux/sched/task.h:11, from include/linux/sched/signal.h:9, from include/linux/rcuwait.h:6, from include/linux/percpu-rwsem.h:7, from include/linux/fs.h:33, from include/linux/huge_mm.h:8, from include/linux/mm.h:707, from arch/powerpc/kernel/signal_32.c:17: arch/powerpc/include/asm/uaccess.h:428: note: macro "unsafe_copy_from_user" defined here 428 | #define unsafe_copy_from_user(d, s, l, e) \ | 572 | unsafe_copy_from_user(current->thread.evr, &sr->mc_vregs, | ^~~~~~~~~~~~~~~~~~~~~ | raw_copy_from_user arch/powerpc/kernel/signal_32.c:572:3: note: each undeclared identifier is reported only once for each function it appears in vim +/unsafe_copy_from_user +573 arch/powerpc/kernel/signal_32.c 502 503 if (!user_read_access_begin(sr, sizeof(*sr))) 504 return 1; 505 /* 506 * restore general registers but not including MSR or SOFTE. Also 507 * take care of keeping r2 (TLS) intact if not a signal 508 */ 509 if (!sig) 510 save_r2 = (unsigned int)regs->gpr[2]; 511 unsafe_restore_general_regs(regs, sr, failed); 512 set_trap_norestart(regs); 513 unsafe_get_user(msr, &sr->mc_gregs[PT_MSR], failed); 514 if (!sig) 515 regs->gpr[2] = (unsigned long) save_r2; 516 517 /* if doing signal return, restore the previous little-endian mode */ 518 if (sig) 519 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE); 520 521 #ifdef CONFIG_ALTIVEC 522 /* 523 * Force the process to reload the altivec registers from 524 * current->thread when it next does altivec instructions 525 */ 526 regs->msr &= ~MSR_VEC; 527 if (msr & MSR_VEC) { 528 /* restore altivec registers from the stack */ 529 unsafe_copy_from_user(&current->thread.vr_state, &sr->mc_vregs, 530 sizeof(sr->mc_vregs), failed); 531 current->thread.used_vr = true; 532 } else if (current->thread.used_vr) 533 memset(&current->thread.vr_state, 0, 534 ELF_NVRREG * sizeof(vector128)); 535 536 /* Always get VRSAVE back */ 537 unsafe_get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32], failed); 538 if (cpu_has_feature(CPU_FTR_ALTIVEC)) 539 mtspr(SPRN_VRSAVE, current->thread.vrsave); 540 #endif /* CONFIG_ALTIVEC */ 541 unsafe_copy_fpr_from_user(current, &sr->mc_fregs, failed); 542 543 #ifdef CONFIG_VSX 544 /* 545 * Force the process to reload the VSX registers from 546 * current->thread when it next does VSX instruction. 547 */ 548 regs->msr &= ~MSR_VSX; 549 if (msr & MSR_VSX) { 550 /* 551 * Restore altivec registers from the stack to a local 552 * buffer, then write this out to the thread_struct 553 */ 554 unsafe_copy_vsx_from_user(current, &sr->mc_vsregs, failed); 555 current->thread.used_vsr = true; 556 } else if (current->thread.used_vsr) 557 for (i = 0; i < 32 ; i++) 558 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0; 559 #endif /* CONFIG_VSX */ 560 /* 561 * force the process to reload the FP registers from 562 * current->thread when it next does FP instructions 563 */ 564 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1); 565 566 #ifdef CONFIG_SPE 567 /* force the process to reload the spe registers from 568 current->thread when it next does spe instructions */ 569 regs->msr &= ~MSR_SPE; 570 if (msr & MSR_SPE) { 571 /* restore spe registers from the stack */ 574 current->thread.used_spe = true; 575 } else if (current->thread.used_spe) 576 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32)); 577 578 /* Always get SPEFSCR back */ 579 unsafe_get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG, failed); 580 #endif /* CONFIG_SPE */ 581 582 user_read_access_end(); 583 return 0; 584 585 failed: 586 user_read_access_end(); 587 return 1; 588 } 589 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org