[lkml]   [2019]   [Feb]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[tip:efi/core] x86: Make ARCH_USE_MEMREMAP_PROT a generic Kconfig symbol
Commit-ID:  ce9084ba0d1d8030adee7038ace32f8d9d423d0f
Author: Ard Biesheuvel <>
AuthorDate: Sat, 2 Feb 2019 10:41:17 +0100
Committer: Ingo Molnar <>
CommitDate: Mon, 4 Feb 2019 08:27:29 +0100

x86: Make ARCH_USE_MEMREMAP_PROT a generic Kconfig symbol

Turn ARCH_USE_MEMREMAP_PROT into a generic Kconfig symbol, and fix the
dependency expression to reflect that AMD_MEM_ENCRYPT depends on it,
instead of the other way around. This will permit ARCH_USE_MEMREMAP_PROT
to be selected by other architectures.

Note that the encryption related early memremap routines in
arch/x86/mm/ioremap.c cannot be built for 32-bit x86 without triggering
the following warning:

arch/x86//mm/ioremap.c: In function 'early_memremap_encrypted':
>> arch/x86/include/asm/pgtable_types.h:193:27: warning: conversion from
'long long unsigned int' to 'long unsigned int' changes
value from '9223372036854776163' to '355' [-Woverflow]
arch/x86//mm/ioremap.c:713:46: note: in expansion of macro '__PAGE_KERNEL_ENC'
return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_ENC);

which essentially means they are 64-bit only anyway. However, we cannot
make them dependent on CONFIG_ARCH_HAS_MEM_ENCRYPT, since that is always
defined, even for i386 (and changing that results in a slew of build errors)

So instead, build those routines only if CONFIG_AMD_MEM_ENCRYPT is

Signed-off-by: Ard Biesheuvel <>
Cc: AKASHI Takahiro <>
Cc: Alexander Graf <>
Cc: Bjorn Andersson <>
Cc: Borislav Petkov <>
Cc: Heinrich Schuchardt <>
Cc: Jeffrey Hugo <>
Cc: Lee Jones <>
Cc: Leif Lindholm <>
Cc: Linus Torvalds <>
Cc: Matt Fleming <>
Cc: Peter Jones <>
Cc: Peter Zijlstra <>
Cc: Sai Praneeth Prakhya <>
Cc: Thomas Gleixner <>
Signed-off-by: Ingo Molnar <>
arch/Kconfig | 3 +++
arch/x86/Kconfig | 5 +----
arch/x86/mm/ioremap.c | 4 ++--
3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/Kconfig b/arch/Kconfig
index 4cfb6de48f79..9f0213213da8 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -885,6 +885,9 @@ config HAVE_ARCH_PREL32_RELOCATIONS
architectures, and don't require runtime relocation on relocatable

+ bool
source "kernel/gcov/Kconfig"

source "scripts/gcc-plugins/Kconfig"
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 68261430fe6e..a7e7a60602fb 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1510,6 +1510,7 @@ config AMD_MEM_ENCRYPT
bool "AMD Secure Memory Encryption (SME) support"
depends on X86_64 && CPU_SUP_AMD
Say yes to enable support for the encryption of system memory.
This requires an AMD processor that supports Secure Memory
@@ -1529,10 +1530,6 @@ config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
If set to N, then the encryption of system memory can be
activated with the mem_encrypt=on command line option.

- def_bool y
- depends on AMD_MEM_ENCRYPT
# Common NUMA Features
config NUMA
bool "Numa Memory Allocation and Scheduler Support"
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 5378d10f1d31..0029604af8a4 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -705,7 +705,7 @@ bool phys_mem_access_encrypted(unsigned long phys_addr, unsigned long size)
return arch_memremap_can_ram_remap(phys_addr, size, 0);

/* Remap memory with encryption */
void __init *early_memremap_encrypted(resource_size_t phys_addr,
unsigned long size)
@@ -747,7 +747,7 @@ void __init *early_memremap_decrypted_wp(resource_size_t phys_addr,

return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_NOENC_WP);

static pte_t bm_pte[PAGE_SIZE/sizeof(pte_t)] __page_aligned_bss;

 \ /
  Last update: 2019-02-04 09:47    [W:0.178 / U:2.256 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site