[GIT PULL] x86 fixes

From: Ingo Molnar
Date: Sun Mar 28 2021 - 06:46:05 EST


Linus,

Please pull the latest x86/urgent git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-urgent-2021-03-28

# HEAD: 9fcb51c14da2953de585c5c6e50697b8a6e91a7b x86/build: Turn off -fcf-protection for realmode targets

Two fixes:

- Fix build failure on Ubuntu with new GCC packages that turn on -fcf-protection

- Fix SME memory encryption PTE encoding bug - AFAICT the code worked on
4K page sizes (level 1) but had the wrong shift at higher page level orders
(level 2 and higher).

Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Thanks,

Ingo

------------------>
Arnd Bergmann (1):
x86/build: Turn off -fcf-protection for realmode targets

Isaku Yamahata (1):
x86/mem_encrypt: Correct physical address calculation in __set_clr_pte_enc()


arch/x86/Makefile | 2 +-
arch/x86/mm/mem_encrypt.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 2d6d5a28c3bf..9a85eae37b17 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -27,7 +27,7 @@ endif
REALMODE_CFLAGS := -m16 -g -Os -DDISABLE_BRANCH_PROFILING \
-Wall -Wstrict-prototypes -march=i386 -mregparm=3 \
-fno-strict-aliasing -fomit-frame-pointer -fno-pic \
- -mno-mmx -mno-sse
+ -mno-mmx -mno-sse $(call cc-option,-fcf-protection=none)

REALMODE_CFLAGS += -ffreestanding
REALMODE_CFLAGS += -fno-stack-protector
diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 4b01f7dbaf30..ae78cef79980 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c
@@ -262,7 +262,7 @@ static void __init __set_clr_pte_enc(pte_t *kpte, int level, bool enc)
if (pgprot_val(old_prot) == pgprot_val(new_prot))
return;

- pa = pfn << page_level_shift(level);
+ pa = pfn << PAGE_SHIFT;
size = page_level_size(level);

/*