> -----Original Message----- > From: [email protected] [mailto:[email protected]] On Behalf Of > Yinghai Lu > Sent: Tuesday, December 11, 2012 9:16 AM > To: Borislav Petkov; Yinghai Lu; H. Peter Anvin; Yu, Fenghua; > [email protected]; [email protected]; [email protected]; > [email protected]; [email protected] > Subject: Re: [tip:x86/microcode] x86/microcode_intel_early.c: Early > update ucode on Intel's CPU > > On Tue, Dec 11, 2012 at 9:06 AM, Borislav Petkov <[email protected]> wrote: > > On Tue, Dec 11, 2012 at 09:00:55AM -0800, Yinghai Lu wrote: > >> ok, then next question is how early it should be. > >> > >> before early_cpu_init/early_identify_cpu > >> > >> or just before check_bugs/identify_cpu > > > > Read the code. It's in x86_64_start_kernel on 64-bit. > > > > No, that is not right place. initrd could be loaded anywhere like way > high by bootloader. > > to make code simple, we should have following sequence in setup_arch > > early_ioremap_init() > early_update_microcode()... > early_cpu_init() > > early_update_microcode could use early_ioremap to access initrd ramdisk > area.
The problem is mainly from 32-bit. We need to load microcode before paging is enabled (I'm changing load_ucode_intel_ap to be called before paging as well). That makes the coding not simple. It's better to load ucode as early as possible in 64-bit as well. I don't want to have two totally different sets of early loading ucode for 64-bit and 32-bit. Thanks. -Fenghua -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
