Re: [PATCH] x86: read apic id if it is not acpi_lapic -v2

Ingo Molnar
2009-05-11T09:20:55Z

* Yinghai Lu <yinghai@kernel.org> wrote:

> + new_apicid = read_apic_id();
> + if (boot_cpu_physical_apicid != new_apicid) {
> + boot_cpu_physical_apicid = new_apicid;
> + apic_version[new_apicid] =
> + GET_APIC_VERSION(apic_read(APIC_LVR));
> }

_Please_, when we override something as critical as this and change
the behavior of Linux (even if it's arguably a fix), we must printk
a single line to the syslog so that people know what's going on.

You really need to make a conscious mental distinction between
'dangerous' code and harmless changes, and apply a lot more
conservative approach when you meet and touch (and introduce ...)
dangerous code.

Thanks,

Ingo