CC: kbuild-all(a)lists.01.org CC: linux-kernel(a)vger.kernel.org CC: x86(a)kernel.org TO: Ingo Molnar <mingo(a)kernel.org&gt; tree: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git master head: 2403d9db4e8ddfbb4457fbb8d83057092d0af409 commit: 4733c2b49742380fa501009f4ee9b8d2ee44c66a [30/40] Merge branch 'WIP.x86/entry' :::::: branch date: :::::: commit date: 2 days ago config: i386-randconfig-m021-20200730 (attached as .config) compiler: gcc-9 (Debian 9.3.0-14) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com&gt; smatch warnings: kernel/entry/common.c:163 exit_to_user_mode_prepare() warn: ignoring unreachable code. arch/x86/entry/common.c:203 idtentry_enter_nmi() warn: statement has no effect 3 # https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=47... git remote add tip https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git git remote update tip git checkout 4733c2b49742380fa501009f4ee9b8d2ee44c66a vim +163 kernel/entry/common.c a9f3a74a29af09 Thomas Gleixner 2020-07-22 158 a9f3a74a29af09 Thomas Gleixner 2020-07-22 159 static void exit_to_user_mode_prepare(struct pt_regs *regs) a9f3a74a29af09 Thomas Gleixner 2020-07-22 160 { a9f3a74a29af09 Thomas Gleixner 2020-07-22 161 unsigned long ti_work = READ_ONCE(current_thread_info()->flags); a9f3a74a29af09 Thomas Gleixner 2020-07-22 162 a9f3a74a29af09 Thomas Gleixner 2020-07-22 @163 lockdep_assert_irqs_disabled(); a9f3a74a29af09 Thomas Gleixner 2020-07-22 164 a9f3a74a29af09 Thomas Gleixner 2020-07-22 165 if (unlikely(ti_work & EXIT_TO_USER_MODE_WORK)) a9f3a74a29af09 Thomas Gleixner 2020-07-22 166 ti_work = exit_to_user_mode_loop(regs, ti_work); a9f3a74a29af09 Thomas Gleixner 2020-07-22 167 a9f3a74a29af09 Thomas Gleixner 2020-07-22 168 arch_exit_to_user_mode_prepare(regs, ti_work); a9f3a74a29af09 Thomas Gleixner 2020-07-22 169 a9f3a74a29af09 Thomas Gleixner 2020-07-22 170 /* Ensure that the address limit is intact and no locks are held */ a9f3a74a29af09 Thomas Gleixner 2020-07-22 171 addr_limit_user_check(); a9f3a74a29af09 Thomas Gleixner 2020-07-22 172 lockdep_assert_irqs_disabled(); a9f3a74a29af09 Thomas Gleixner 2020-07-22 173 lockdep_sys_exit(); a9f3a74a29af09 Thomas Gleixner 2020-07-22 174 } a9f3a74a29af09 Thomas Gleixner 2020-07-22 175 :::::: The code at line 163 was first introduced by commit :::::: a9f3a74a29af095f3e1b89e9176f8127912ae0f0 entry: Provide generic syscall exit function :::::: TO: Thomas Gleixner <tglx(a)linutronix.de&gt; :::::: CC: Thomas Gleixner <tglx(a)linutronix.de&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org