On Fri, 18 Dec 2015 22:39:22 +0800 kbuild test robot <fengguang.wu@xxxxxxxxx> wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > head: f7ac28a6971b43a2ee8bb47c0ef931b38f7888cf > commit: 64dab25b058c12f935794cb239089303bda7dbc1 [7056/7206] kernel/stop_machine.c: remove CONFIG_SMP dependencies > config: m32r-usrv_defconfig (attached as .config) > reproduce: > wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross > chmod +x ~/bin/make.cross > git checkout 64dab25b058c12f935794cb239089303bda7dbc1 > # save the attached .config to linux build tree > make.cross ARCH=m32r > > All errors (new ones prefixed by >>): > > kernel/built-in.o: In function `timekeeping_notify': > >> kernel/time/timekeeping.c:1096: undefined reference to `stop_machine' > kernel/time/timekeeping.c:1096:(.text+0x51498): relocation truncated to fit: R_M32R_26_PCREL_RELA against undefined symbol `stop_machine' > mm/built-in.o: In function `build_all_zonelists': > >> mm/page_alloc.c:4508: undefined reference to `stop_machine' > mm/page_alloc.c:4508:(.ref.text+0x1f4): relocation truncated to fit: R_M32R_26_PCREL_RELA against undefined symbol `stop_machine' > doh. From: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Subject: kernel-stop_machinec-remove-config_smp-dependencies-fix stop_machine.o is only built if CONFIG_SMP=y, so this ifdef always evaluates to true. Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Valentin Rothberg <valentinrothberg@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/stop_machine.c | 4 ---- 1 file changed, 4 deletions(-) diff -puN kernel/stop_machine.c~kernel-stop_machinec-remove-config_smp-dependencies-fix kernel/stop_machine.c --- a/kernel/stop_machine.c~kernel-stop_machinec-remove-config_smp-dependencies-fix +++ a/kernel/stop_machine.c @@ -531,8 +531,6 @@ static int __init cpu_stop_init(void) } early_initcall(cpu_stop_init); -#ifdef CONFIG_HOTPLUG_CPU - static int __stop_machine(cpu_stop_fn_t fn, void *data, const struct cpumask *cpus) { struct multi_stop_data msdata = { @@ -630,5 +628,3 @@ int stop_machine_from_inactive_cpu(cpu_s mutex_unlock(&stop_cpus_mutex); return ret ?: done.ret; } - -#endif /* CONFIG_HOTPLUG_CPU */ _ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>