On Thu, 2016-08-18 at 11:47 +0200, Ingo Molnar wrote: > * Wei Jiangang <weijg.f...@cn.fujitsu.com> wrote: > > > Check the boot APIC ID firstly, > > and then setup the default routing of APIC looks better. > > > > And move default_setup_apic_routing() close to apic_bsp_setup(), > > which staying in step with the codes in APIC_init_uniprocessor(). > > > > Signed-off-by: Wei Jiangang <weijg.f...@cn.fujitsu.com> > > --- > > arch/x86/kernel/smpboot.c | 3 +-- > > 1 file changed, 1 insertion(+), 2 deletions(-) > > If it's not a bug then please clearly note so in the changelog and > explain why the change results in better code.
It's not a bug. The combination of default_setup_apic_routing() and apic_bsp_setup() is used to enable APIC mode. If the return of read_apic_id() is not equal to boot_cpu_physical_apicid, it means the APIC ID of current CPU‘s local APIC is unexpected and enable APIC mode maybe fail. so no need to set up the apic routing. That's why I want to move default_setup_apic_routing() behind checking the boot APIC ID. Sorry for obscure commit message. I will improve it in next version. > > If it's fixing a bug/misfeature then please fix the changelog to > conform to the standard changelog style: > > - first describe the symptoms of the bug - how does a user notice? > > - then describe how the code behaves today and how that is causing the bug > > - and then only describe how it's fixed. Thanks for your detailed explanation. I'll keep in my mind. > > Thanks, > > Ingo > >
