From: Ard Biesheuvel ard.biesheuvel@linaro.org
commit ce9084ba0d1d8030adee7038ace32f8d9d423d0f upstream.
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] #define __PAGE_KERNEL_ENC (__PAGE_KERNEL | _PAGE_ENC) ^~~~~~~~~~~~~~~~~~~~~~~~~~~ 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 defined.
Signed-off-by: Ard Biesheuvel ard.biesheuvel@linaro.org Cc: AKASHI Takahiro takahiro.akashi@linaro.org Cc: Alexander Graf agraf@suse.de Cc: Bjorn Andersson bjorn.andersson@linaro.org Cc: Borislav Petkov bp@alien8.de Cc: Heinrich Schuchardt xypron.glpk@gmx.de Cc: Jeffrey Hugo jhugo@codeaurora.org Cc: Lee Jones lee.jones@linaro.org Cc: Leif Lindholm leif.lindholm@linaro.org Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Matt Fleming matt@codeblueprint.co.uk Cc: Peter Jones pjones@redhat.com Cc: Peter Zijlstra peterz@infradead.org Cc: Sai Praneeth Prakhya sai.praneeth.prakhya@intel.com Cc: Thomas Gleixner tglx@linutronix.de Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20190202094119.13230-9-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/Kconfig | 3 +++ arch/x86/Kconfig | 5 +---- arch/x86/mm/ioremap.c | 4 ++-- 3 files changed, 6 insertions(+), 6 deletions(-)
--- a/arch/Kconfig +++ b/arch/Kconfig @@ -980,4 +980,7 @@ config HAVE_ARCH_COMPILER_H linux/compiler-*.h in order to override macro definitions that those headers generally provide.
+config ARCH_USE_MEMREMAP_PROT + bool + source "kernel/gcov/Kconfig" --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1449,6 +1449,7 @@ config ARCH_HAS_MEM_ENCRYPT config AMD_MEM_ENCRYPT bool "AMD Secure Memory Encryption (SME) support" depends on X86_64 && CPU_SUP_AMD + select ARCH_USE_MEMREMAP_PROT ---help--- Say yes to enable support for the encryption of system memory. This requires an AMD processor that supports Secure Memory @@ -1467,10 +1468,6 @@ 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.
-config ARCH_USE_MEMREMAP_PROT - def_bool y - depends on AMD_MEM_ENCRYPT - # Common NUMA Features config NUMA bool "Numa Memory Allocation and Scheduler Support" --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -626,7 +626,7 @@ bool phys_mem_access_encrypted(unsigned return arch_memremap_can_ram_remap(phys_addr, size, 0); }
-#ifdef CONFIG_ARCH_USE_MEMREMAP_PROT +#ifdef CONFIG_AMD_MEM_ENCRYPT /* Remap memory with encryption */ void __init *early_memremap_encrypted(resource_size_t phys_addr, unsigned long size) @@ -668,7 +668,7 @@ void __init *early_memremap_decrypted_wp
return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_NOENC_WP); } -#endif /* CONFIG_ARCH_USE_MEMREMAP_PROT */ +#endif /* CONFIG_AMD_MEM_ENCRYPT */
static pte_t bm_pte[PAGE_SIZE/sizeof(pte_t)] __page_aligned_bss;