Hi Zong-Zhe, First bad commit (maybe != root cause): tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: fb893de323e2d39f7a1f6df425703a2edbdf56ea commit: ba0fbe236fb8a7b992e82d6eafb03a600f5eba43 rtw88: extract: make 8822c an individual kernel module date: 3 months ago config: parisc-randconfig-m031-20200811 (attached as .config) compiler: hppa-linux-gcc (GCC) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; smatch warnings: drivers/net/wireless/realtek/rtw88/phy.c:641 rtw_phy_linear_2_db() error: buffer overflow 'db_invert_table[i]' 8 <= 8 (assuming for loop doesn't break) vim +641 drivers/net/wireless/realtek/rtw88/phy.c e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 599 e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 600 static u8 rtw_phy_linear_2_db(u64 linear) e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 601 { e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 602 u8 i; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 603 u8 j; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 604 u32 dB; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 605 e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 606 if (linear >= db_invert_table[11][7]) e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 607 return 96; /* maximum 96 dB */ e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 608 e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 609 for (i = 0; i < 12; i++) { e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 610 if (i <= 2 && (linear << FRAC_BITS) <= db_invert_table[i][7]) e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 611 break; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 612 else if (i > 2 && linear <= db_invert_table[i][7]) e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 613 break; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 614 } e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 615 e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 616 for (j = 0; j < 8; j++) { e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 617 if (i <= 2 && (linear << FRAC_BITS) <= db_invert_table[i][j]) e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 618 break; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 619 else if (i > 2 && linear <= db_invert_table[i][j]) e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 620 break; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 621 } e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 622 e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 623 if (j == 0 && i == 0) e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 624 goto end; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 625 e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 626 if (j == 0) { e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 627 if (i != 3) { e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 628 if (db_invert_table[i][0] - linear > e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 629 linear - db_invert_table[i - 1][7]) { e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 630 i = i - 1; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 631 j = 7; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 632 } e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 633 } else { e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 634 if (db_invert_table[3][0] - linear > e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 635 linear - db_invert_table[2][7]) { e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 636 i = 2; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 637 j = 7; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 638 } e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 639 } e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 640 } else { e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 @641 if (db_invert_table[i][j] - linear > e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 642 linear - db_invert_table[i][j - 1]) { e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 643 j = j - 1; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 644 } e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 645 } e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 646 end: e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 647 dB = (i << 3) + j + 1; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 648 e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 649 return dB; e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 650 } e3037485c68ec1 Yan-Hsuan Chuang 2019-04-26 651 :::::: The code at line 641 was first introduced by commit :::::: e3037485c68ec1a299ff41160d8fedbd4abc29b9 rtw88: new Realtek 802.11ac driver :::::: TO: Yan-Hsuan Chuang <yhchuang(a)realtek.com&gt; :::::: CC: Kalle Valo <kvalo(a)codeaurora.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org