On Wed, Mar 2, 2016 at 5:00 PM, Yinghai Lu <ying...@kernel.org> wrote: > On Wed, Mar 2, 2016 at 4:13 PM, Yinghai Lu <ying...@kernel.org> wrote: >> On Wed, Mar 2, 2016 at 2:32 PM, H. Peter Anvin <h...@zytor.com> wrote: >>> >>> I'm trying to think of any reason why we couldn't simply have a symbol at >>> the top of the initial stack? Then a simple leaq would suffice; this is >>> for the BSP after all. >> >> Why do we need to call verify_cpu in arch/x86/kernel/head_64.S aka the >> vmlinux again ? >> >> Is that already called in arch/x86/boot/compressed/head_64.S? > > that calling is from startup_32, so may add another calling in startup_64, > so can avoid calling from arch/x86/kernel/head_64.S >
at the same time, the "call verify_cpu" in arch/x86/kernel/head_64.s::secondary_startup_64() is not needed. As APs already go through arch/x86/realmode/rm/trampoline_64.S::trampoline_start(), and it already call verify_cpu in 16bit mode. Thanks Yinghai
