[PATCH v6 17/22] powerpc/book3s64/kuap: Use Key 3 to implement KUAP with hash translation.
From: Aneesh Kumar K.V <hidden>
Date: 2020-11-25 05:49:42
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
Radix use AMR Key 0 and hash translation use AMR key 3. Reviewed-by: Sandipan Das <redacted> Signed-off-by: Aneesh Kumar K.V <redacted> --- arch/powerpc/include/asm/book3s/64/kup.h | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/kup.h b/arch/powerpc/include/asm/book3s/64/kup.h
index 2922c442a218..b8861cc2b6c7 100644
--- a/arch/powerpc/include/asm/book3s/64/kup.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h@@ -5,11 +5,10 @@ #include <linux/const.h> #include <asm/reg.h> -#define AMR_KUAP_BLOCK_READ UL(0x4000000000000000) -#define AMR_KUAP_BLOCK_WRITE UL(0x8000000000000000) +#define AMR_KUAP_BLOCK_READ UL(0x5455555555555555) +#define AMR_KUAP_BLOCK_WRITE UL(0xa8aaaaaaaaaaaaaa) #define AMR_KUEP_BLOCKED (1UL << 62) #define AMR_KUAP_BLOCKED (AMR_KUAP_BLOCK_READ | AMR_KUAP_BLOCK_WRITE) -#define AMR_KUAP_SHIFT 62 #ifdef __ASSEMBLY__
@@ -62,8 +61,8 @@ #ifdef CONFIG_PPC_KUAP_DEBUG BEGIN_MMU_FTR_SECTION_NESTED(67) mfspr \gpr1, SPRN_AMR - li \gpr2, (AMR_KUAP_BLOCKED >> AMR_KUAP_SHIFT) - sldi \gpr2, \gpr2, AMR_KUAP_SHIFT + /* Prevent access to userspace using any key values */ + LOAD_REG_IMMEDIATE(\gpr2, AMR_KUAP_BLOCKED) 999: tdne \gpr1, \gpr2 EMIT_BUG_ENTRY 999b, __FILE__, __LINE__, (BUGFLAG_WARNING | BUGFLAG_ONCE) END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_KUAP, 67)
--
2.28.0