On 11/22/22 10:10, Ard Biesheuvel wrote:
After doing some cleanup work on the EFI code in head_64.S, the mixed mode code in particular, I noticed that the memory encryption pieces could use some attention as well, so I cleaned that up too. Changes since v2: - add some clarifying comments to the EFI mixed mode changes - include patch to make the EFI handover protocol optional that was sent out separately before - rebase onto tip/master Changes since v1: - at Boris's request, split the patches into smaller ones that are easier to review Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: Michael Roth <michael.roth@xxxxxxx>
This causes an SEV guest to blow up on boot in the early boot code. It looks like the stack pointer is not valid and it triple faults on a pushq instruction (pushq $__KERNEL_CS in arch/x86/boot/compressed/head_64.S of startup_64). Here is the Qemu register dump: RAX=00000000029cc260 RBX=ffffffffdd98c000 RCX=0000000000000010 RDX=0000000000000002 RSI=000000003dec1000 RDI=0000000000000000 RBP=ffffffffdb000000 RSP=ffffffffde36e000 R8 =000000003dec1410 R9 =000000003dec13fc R10=000000000000006c R11=0000000000000000 R12=0000000000000000 R13=0000000000000001 R14=0000000000000004 R15=000000003eacdf44 RIP=0000000002000263 RFL=00200002 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0 ES =0000 0000000000000000 00000000 00000000 CS =0038 0000000000000000 ffffffff 00a09b00 DPL=0 CS64 [-RA] SS =0000 0000000000000000 00000000 00000000 DS =0000 0000000000000000 00000000 00000000 FS =0000 0000000000000000 00000000 00000000 GS =0000 0000000000000000 00000000 00000000 LDT=0000 0000000000000000 0000ffff 00008200 DPL=0 LDT TR =0000 0000000000000000 0000ffff 00008b00 DPL=0 TSS64-busy GDT= 00000000029cc270 0000002f IDT= 000000003f55e018 00000fff CR0=80010033 CR2=ffffffffde36dff8 CR3=000000003fc01000 CR4=00000668 DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 DR3=0000000000000000 DR6=00000000ffff0ff0 DR7=0000000000000400 EFER=0000000000000d00 Thanks, Tom
Ard Biesheuvel (17): x86/compressed: efi-mixed: rename efi_thunk_64.S to efi-mixed.S x86/compressed: efi-mixed: move 32-bit entrypoint code into .text section x86/compressed: efi-mixed: move bootargs parsing out of 32-bit startup code x86/compressed: efi-mixed: move efi32_pe_entry into .text section x86/compressed: efi-mixed: move efi32_entry out of head_64.S x86/compressed: efi-mixed: move efi32_pe_entry() out of head_64.S x86/compressed: efi: merge multiple definitions of image_offset into one x86/compressed: efi-mixed: simplify IDT/GDT preserve/restore x86/compressed: avoid touching ECX in startup32_set_idt_entry() x86/compressed: pull global variable ref up into startup32_load_idt() x86/compressed: move startup32_load_idt() into .text section x86/compressed: move startup32_load_idt() out of head_64.S x86/compressed: move startup32_check_sev_cbit() into .text x86/compressed: move startup32_check_sev_cbit() out of head_64.S x86/compressed: adhere to calling convention in get_sev_encryption_bit() x86/compressed: only build mem_encrypt.S if AMD_MEM_ENCRYPT=y efi: x86: Make the deprecated EFI handover protocol optional arch/x86/Kconfig | 17 + arch/x86/boot/compressed/Makefile | 8 +- arch/x86/boot/compressed/efi_mixed.S | 351 ++++++++++++++++++++ arch/x86/boot/compressed/efi_thunk_64.S | 195 ----------- arch/x86/boot/compressed/head_32.S | 4 - arch/x86/boot/compressed/head_64.S | 303 +---------------- arch/x86/boot/compressed/mem_encrypt.S | 152 ++++++++- arch/x86/boot/header.S | 2 +- arch/x86/boot/tools/build.c | 2 + drivers/firmware/efi/libstub/x86-stub.c | 2 +- 10 files changed, 533 insertions(+), 503 deletions(-) create mode 100644 arch/x86/boot/compressed/efi_mixed.S delete mode 100644 arch/x86/boot/compressed/efi_thunk_64.S