Commit-ID: 163ea3c83aeeb3908a51162c79cb3a7c374d92b4 Gitweb: http://git.kernel.org/tip/163ea3c83aeeb3908a51162c79cb3a7c374d92b4 Author: Tom Lendacky <[email protected]> AuthorDate: Mon, 17 Jul 2017 16:10:20 -0500 Committer: Ingo Molnar <[email protected]> CommitDate: Tue, 18 Jul 2017 11:38:03 +0200
x86/realmode: Decrypt trampoline area if memory encryption is active When Secure Memory Encryption is enabled, the trampoline area must not be encrypted. A CPU running in real mode will not be able to decrypt memory that has been encrypted because it will not be able to use addresses with the memory encryption mask. Signed-off-by: Tom Lendacky <[email protected]> Reviewed-by: Thomas Gleixner <[email protected]> Reviewed-by: Borislav Petkov <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brijesh Singh <[email protected]> Cc: Dave Young <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Konrad Rzeszutek Wilk <[email protected]> Cc: Larry Woodman <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Matt Fleming <[email protected]> Cc: Michael S. Tsirkin <[email protected]> Cc: Paolo Bonzini <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Radim Krčmář <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Toshimitsu Kani <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: http://lkml.kernel.org/r/c70ffd2614fa77e80df31c9169ca98a9b16ff97c.1500319216.git.thomas.lenda...@amd.com Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/realmode/init.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c index cd4be19..d6ddc7e 100644 --- a/arch/x86/realmode/init.c +++ b/arch/x86/realmode/init.c @@ -1,6 +1,7 @@ #include <linux/io.h> #include <linux/slab.h> #include <linux/memblock.h> +#include <linux/mem_encrypt.h> #include <asm/set_memory.h> #include <asm/pgtable.h> @@ -59,6 +60,13 @@ static void __init setup_real_mode(void) base = (unsigned char *)real_mode_header; + /* + * If SME is active, the trampoline area will need to be in + * decrypted memory in order to bring up other processors + * successfully. + */ + set_memory_decrypted((unsigned long)base, size >> PAGE_SHIFT); + memcpy(base, real_mode_blob, size); phys_base = __pa(base);

