Re: AMD SME + KASAN = doom

From: Borislav Petkov
Date: Sat Jun 13 2020 - 11:55:02 EST


On Sat, Jun 13, 2020 at 11:24:08AM -0400, Qian Cai wrote:
> CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT=y + KASAN (inline) will reset
> the host right away after those lines on linux-next (the mainline has
> the same problem when I tested a while back, so it seems never work),

$ head arch/x86/mm/Makefile
# SPDX-License-Identifier: GPL-2.0
# Kernel does not boot with instrumentation of tlb.c and mem_encrypt*.c
KCOV_INSTRUMENT_tlb.o := n
KCOV_INSTRUMENT_mem_encrypt.o := n
KCOV_INSTRUMENT_mem_encrypt_identity.o := n

KASAN_SANITIZE_mem_encrypt.o := n
KASAN_SANITIZE_mem_encrypt_identity.o := n

so something else needs to be de-KASAN-ed too.

For now flip your Subject: AMD SME - KASAN = boot.

--
Regards/Gruss,
Boris.

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