On Wed, Nov 10, 2021 at 05:37:32PM +0100, Borislav Petkov wrote: > On Mon, Sep 13, 2021 at 05:55:58PM +0200, Joerg Roedel wrote: > > extern unsigned char real_mode_blob[]; > > diff --git a/arch/x86/include/asm/sev-ap-jumptable.h b/arch/x86/include/asm/sev-ap-jumptable.h > > new file mode 100644 > > index 000000000000..1c8b2ce779e2 > > --- /dev/null > > +++ b/arch/x86/include/asm/sev-ap-jumptable.h > > Why a separate header? arch/x86/include/asm/sev.h looks small enough. The header is included in assembly, so I made a separate one. > > +void __init sev_es_setup_ap_jump_table_data(void *base, u32 pa) > > Why is this a separate function? > > It is all part of the jump table setup. Right, but the sev_es_setup_ap_jump_table_blob() function is already pretty big and I wanted to keep things readable. > > > + return 0; > > Why are you returning 0 here and below? This is in an initcall and it returns just 0 when the environment is not ready to setup the ap jump table. Returning non-zero would create a warning message in the caller for something that is not a bug in the kernel. > > + * This file contains the source code for the binary blob which gets copied to > > + * the SEV-ES AP Jumptable to park APs while offlining CPUs or booting a new > > I've seen "Jumptable", "Jump Table" and "jump table" at least. I'd say, do > the last one everywhere pls. Fair, sorry for my english being too german :) I changed everything to 'jump table'. > > + /* Reset remaining registers */ > > + movl $0, %esp > > + movl $0, %eax > > + movl $0, %ebx > > + movl $0, %edx > > All 4: use xor XOR changes EFLAGS, can not use them here. > > + > > + /* Reset CR0 to get out of protected mode */ > > + movl $0x60000010, %ecx > > Another magic naked number. This is the CR0 reset value. I have updated the comment to make this more clear. Thanks, -- Jörg Rödel jroedel@xxxxxxx SUSE Software Solutions Germany GmbH Maxfeldstr. 5 90409 Nürnberg Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Ivo Totev
