diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c index f4873a64f46dcb2dac8db0c3585afecc642e70ee..be52744904284c3360d55b2d1555497c14008fd1 100644 --- a/arch/x86/kernel/cpu/mcheck/mce_amd.c +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c @@ -777,4 +777,24 @@ static __init int threshold_init_device(void) return 0; } -device_initcall(threshold_init_device); +/* + * there are 3 funcs which need to be _initcalled in a logic sequence: + * 1. xen_late_init_mcelog + * 2. mcheck_init_device + * 3. threshold_init_device + * + * xen_late_init_mcelog must register xen_mce_chrdev_device before + * native mce_chrdev_device registration if running under xen platform; + * + * mcheck_init_device should be inited before threshold_init_device to + * initialize mce_device, otherwise a NULL ptr dereference will cause panic. + * + * so we use following _initcalls + * 1. device_initcall(xen_late_init_mcelog); + * 2. device_initcall_sync(mcheck_init_device); + * 3. late_initcall(threshold_init_device); + * + * when running under xen, the initcall order is 1,2,3; + * on baremetal, we skip 1 and we do only 2 and 3. + */ +late_initcall(threshold_init_device);