diff options
author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2023-03-12 14:26:06 +0300 |
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committer | Dave Hansen <dave.hansen@linux.intel.com> | 2023-03-16 23:08:40 +0300 |
commit | 23e5d9ec2bab53c4e5fbac675304e699726c1ac5 (patch) | |
tree | 4a147d3d5733a4b57a1e4d4e99f99e62553fdc17 /arch/x86/include/asm/mmu.h | |
parent | 400b9b93441cd4e2fe824a70140f3d5a2a9c802b (diff) | |
download | linux-23e5d9ec2bab53c4e5fbac675304e699726c1ac5.tar.xz |
x86/mm/iommu/sva: Make LAM and SVA mutually exclusive
IOMMU and SVA-capable devices know nothing about LAM and only expect
canonical addresses. An attempt to pass down tagged pointer will lead
to address translation failure.
By default do not allow to enable both LAM and use SVA in the same
process.
The new ARCH_FORCE_TAGGED_SVA arch_prctl() overrides the limitation.
By using the arch_prctl() userspace takes responsibility to never pass
tagged address to the device.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/all/20230312112612.31869-12-kirill.shutemov%40linux.intel.com
Diffstat (limited to 'arch/x86/include/asm/mmu.h')
-rw-r--r-- | arch/x86/include/asm/mmu.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/include/asm/mmu.h b/arch/x86/include/asm/mmu.h index e80762e998ce..0da5c227f490 100644 --- a/arch/x86/include/asm/mmu.h +++ b/arch/x86/include/asm/mmu.h @@ -14,6 +14,8 @@ #define MM_CONTEXT_HAS_VSYSCALL 1 /* Do not allow changing LAM mode */ #define MM_CONTEXT_LOCK_LAM 2 +/* Allow LAM and SVA coexisting */ +#define MM_CONTEXT_FORCE_TAGGED_SVA 3 /* * x86 has arch-specific MMU state beyond what lives in mm_struct. |