Currently a nop config. Keeping as a separate commit for easy review of the boring bits. Later commits will use and enable this new config. This config is only added for non-UML x86_64 as other architectures do not yet have pending implementations. It also has somewhat artificial dependencies on !PARAVIRT and !KASAN which are explained in the Kconfig file. Co-developed-by: Junaid Shahid <junaids@xxxxxxxxxx> Signed-off-by: Brendan Jackman <jackmanb@xxxxxxxxxx> --- arch/alpha/include/asm/Kbuild | 1 + arch/arc/include/asm/Kbuild | 1 + arch/arm/include/asm/Kbuild | 1 + arch/arm64/include/asm/Kbuild | 1 + arch/csky/include/asm/Kbuild | 1 + arch/hexagon/include/asm/Kbuild | 1 + arch/loongarch/include/asm/Kbuild | 1 + arch/m68k/include/asm/Kbuild | 1 + arch/microblaze/include/asm/Kbuild | 1 + arch/mips/include/asm/Kbuild | 1 + arch/nios2/include/asm/Kbuild | 1 + arch/openrisc/include/asm/Kbuild | 1 + arch/parisc/include/asm/Kbuild | 1 + arch/powerpc/include/asm/Kbuild | 1 + arch/riscv/include/asm/Kbuild | 1 + arch/s390/include/asm/Kbuild | 1 + arch/sh/include/asm/Kbuild | 1 + arch/sparc/include/asm/Kbuild | 1 + arch/um/include/asm/Kbuild | 1 + arch/x86/Kconfig | 19 +++++++++++++++++++ arch/xtensa/include/asm/Kbuild | 1 + include/asm-generic/asi.h | 5 +++++ 22 files changed, 44 insertions(+) diff --git a/arch/alpha/include/asm/Kbuild b/arch/alpha/include/asm/Kbuild index 396caece6d6d9..ca72ce3baca13 100644 --- a/arch/alpha/include/asm/Kbuild +++ b/arch/alpha/include/asm/Kbuild @@ -5,3 +5,4 @@ generic-y += agp.h generic-y += asm-offsets.h generic-y += kvm_para.h generic-y += mcs_spinlock.h +generic-y += asi.h diff --git a/arch/arc/include/asm/Kbuild b/arch/arc/include/asm/Kbuild index 3c1afa524b9c2..60bdeffa7c31e 100644 --- a/arch/arc/include/asm/Kbuild +++ b/arch/arc/include/asm/Kbuild @@ -4,3 +4,4 @@ generic-y += kvm_para.h generic-y += mcs_spinlock.h generic-y += parport.h generic-y += user.h +generic-y += asi.h diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild index 03657ff8fbe3d..1e2c3d8dbbd99 100644 --- a/arch/arm/include/asm/Kbuild +++ b/arch/arm/include/asm/Kbuild @@ -6,3 +6,4 @@ generic-y += parport.h generated-y += mach-types.h generated-y += unistd-nr.h +generic-y += asi.h diff --git a/arch/arm64/include/asm/Kbuild b/arch/arm64/include/asm/Kbuild index 4b6d2d52053e4..f95699a559309 100644 --- a/arch/arm64/include/asm/Kbuild +++ b/arch/arm64/include/asm/Kbuild @@ -5,6 +5,7 @@ generic-y += qrwlock.h generic-y += qspinlock.h generic-y += parport.h generic-y += user.h +generic-y += asi.h generated-y += cpucap-defs.h generated-y += sysreg-defs.h diff --git a/arch/csky/include/asm/Kbuild b/arch/csky/include/asm/Kbuild index 1117c28cb7e8a..5e49ccb571644 100644 --- a/arch/csky/include/asm/Kbuild +++ b/arch/csky/include/asm/Kbuild @@ -10,3 +10,4 @@ generic-y += qspinlock.h generic-y += parport.h generic-y += user.h generic-y += vmlinux.lds.h +generic-y += asi.h \ No newline at end of file diff --git a/arch/hexagon/include/asm/Kbuild b/arch/hexagon/include/asm/Kbuild index 3ece3c93fe086..744ffbeeb7ae4 100644 --- a/arch/hexagon/include/asm/Kbuild +++ b/arch/hexagon/include/asm/Kbuild @@ -3,3 +3,4 @@ generic-y += extable.h generic-y += iomap.h generic-y += kvm_para.h generic-y += mcs_spinlock.h +generic-y += asi.h diff --git a/arch/loongarch/include/asm/Kbuild b/arch/loongarch/include/asm/Kbuild index 2dbec7853ae86..66fcd325d6083 100644 --- a/arch/loongarch/include/asm/Kbuild +++ b/arch/loongarch/include/asm/Kbuild @@ -27,3 +27,4 @@ generic-y += param.h generic-y += posix_types.h generic-y += resource.h generic-y += kvm_para.h +generic-y += asi.h diff --git a/arch/m68k/include/asm/Kbuild b/arch/m68k/include/asm/Kbuild index 0dbf9c5c6faeb..faf0f135df4ab 100644 --- a/arch/m68k/include/asm/Kbuild +++ b/arch/m68k/include/asm/Kbuild @@ -4,3 +4,4 @@ generic-y += extable.h generic-y += kvm_para.h generic-y += mcs_spinlock.h generic-y += spinlock.h +generic-y += asi.h diff --git a/arch/microblaze/include/asm/Kbuild b/arch/microblaze/include/asm/Kbuild index a055f5dbe00a3..012e4bf83c134 100644 --- a/arch/microblaze/include/asm/Kbuild +++ b/arch/microblaze/include/asm/Kbuild @@ -8,3 +8,4 @@ generic-y += parport.h generic-y += syscalls.h generic-y += tlb.h generic-y += user.h +generic-y += asi.h diff --git a/arch/mips/include/asm/Kbuild b/arch/mips/include/asm/Kbuild index 7ba67a0d6c97b..3191699298d80 100644 --- a/arch/mips/include/asm/Kbuild +++ b/arch/mips/include/asm/Kbuild @@ -13,3 +13,4 @@ generic-y += parport.h generic-y += qrwlock.h generic-y += qspinlock.h generic-y += user.h +generic-y += asi.h diff --git a/arch/nios2/include/asm/Kbuild b/arch/nios2/include/asm/Kbuild index 7fe7437555fb4..bfdc4026c5b16 100644 --- a/arch/nios2/include/asm/Kbuild +++ b/arch/nios2/include/asm/Kbuild @@ -5,3 +5,4 @@ generic-y += kvm_para.h generic-y += mcs_spinlock.h generic-y += spinlock.h generic-y += user.h +generic-y += asi.h diff --git a/arch/openrisc/include/asm/Kbuild b/arch/openrisc/include/asm/Kbuild index c8c99b554ca4c..d137c4e08e369 100644 --- a/arch/openrisc/include/asm/Kbuild +++ b/arch/openrisc/include/asm/Kbuild @@ -7,3 +7,4 @@ generic-y += spinlock.h generic-y += qrwlock_types.h generic-y += qrwlock.h generic-y += user.h +generic-y += asi.h diff --git a/arch/parisc/include/asm/Kbuild b/arch/parisc/include/asm/Kbuild index 4fb596d94c893..3cbb4eb14712c 100644 --- a/arch/parisc/include/asm/Kbuild +++ b/arch/parisc/include/asm/Kbuild @@ -5,3 +5,4 @@ generic-y += agp.h generic-y += kvm_para.h generic-y += mcs_spinlock.h generic-y += user.h +generic-y += asi.h diff --git a/arch/powerpc/include/asm/Kbuild b/arch/powerpc/include/asm/Kbuild index 61a8d5555cd7e..103c7e2f66987 100644 --- a/arch/powerpc/include/asm/Kbuild +++ b/arch/powerpc/include/asm/Kbuild @@ -8,3 +8,4 @@ generic-y += mcs_spinlock.h generic-y += qrwlock.h generic-y += vtime.h generic-y += early_ioremap.h +generic-y += asi.h diff --git a/arch/riscv/include/asm/Kbuild b/arch/riscv/include/asm/Kbuild index 504f8b7e72d41..08c199a56731e 100644 --- a/arch/riscv/include/asm/Kbuild +++ b/arch/riscv/include/asm/Kbuild @@ -9,3 +9,4 @@ generic-y += qrwlock.h generic-y += qrwlock_types.h generic-y += user.h generic-y += vmlinux.lds.h +generic-y += asi.h diff --git a/arch/s390/include/asm/Kbuild b/arch/s390/include/asm/Kbuild index 4b904110d27cb..b5caf77e8d955 100644 --- a/arch/s390/include/asm/Kbuild +++ b/arch/s390/include/asm/Kbuild @@ -7,3 +7,4 @@ generated-y += unistd_nr.h generic-y += asm-offsets.h generic-y += kvm_types.h generic-y += mcs_spinlock.h +generic-y += asi.h diff --git a/arch/sh/include/asm/Kbuild b/arch/sh/include/asm/Kbuild index fc44d9c88b419..ea19e45158285 100644 --- a/arch/sh/include/asm/Kbuild +++ b/arch/sh/include/asm/Kbuild @@ -3,3 +3,4 @@ generated-y += syscall_table.h generic-y += kvm_para.h generic-y += mcs_spinlock.h generic-y += parport.h +generic-y += asi.h diff --git a/arch/sparc/include/asm/Kbuild b/arch/sparc/include/asm/Kbuild index 43b0ae4c2c211..cb9062c9be17f 100644 --- a/arch/sparc/include/asm/Kbuild +++ b/arch/sparc/include/asm/Kbuild @@ -4,3 +4,4 @@ generated-y += syscall_table_64.h generic-y += agp.h generic-y += kvm_para.h generic-y += mcs_spinlock.h +generic-y += asi.h diff --git a/arch/um/include/asm/Kbuild b/arch/um/include/asm/Kbuild index b2d834a29f3a9..1bcb16b09dc49 100644 --- a/arch/um/include/asm/Kbuild +++ b/arch/um/include/asm/Kbuild @@ -28,3 +28,4 @@ generic-y += trace_clock.h generic-y += kprobes.h generic-y += mm_hooks.h generic-y += vga.h +generic-y += asi.h diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 928820e61cb50..ff74aa53842ea 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2516,6 +2516,25 @@ config MITIGATION_PAGE_TABLE_ISOLATION See Documentation/arch/x86/pti.rst for more details. +config MITIGATION_ADDRESS_SPACE_ISOLATION + bool "Allow code to run with a reduced kernel address space" + default n + depends on X86_64 && !PARAVIRT && !KASAN && !UML + help + This feature provides the ability to run some kernel code + with a reduced kernel address space. This can be used to + mitigate some speculative execution attacks. + + The !PARAVIRT dependency is only because of lack of testing; in theory + the code is written to work under paravirtualization. In practice + there are likely to be unhandled cases, in particular concerning TLB + flushes. + + The !KASAN dependency is mainly because ASI creates a secondary + direct-map region in order to implement local-nonsensitive memory. + This dependencies will later be removed with extensions to the KASAN + implementation. + config MITIGATION_RETPOLINE bool "Avoid speculative indirect branches in kernel" select OBJTOOL if HAVE_OBJTOOL diff --git a/arch/xtensa/include/asm/Kbuild b/arch/xtensa/include/asm/Kbuild index fa07c686cbcc2..07cea6902f980 100644 --- a/arch/xtensa/include/asm/Kbuild +++ b/arch/xtensa/include/asm/Kbuild @@ -8,3 +8,4 @@ generic-y += parport.h generic-y += qrwlock.h generic-y += qspinlock.h generic-y += user.h +generic-y += asi.h diff --git a/include/asm-generic/asi.h b/include/asm-generic/asi.h new file mode 100644 index 0000000000000..c4d9a5ff860a9 --- /dev/null +++ b/include/asm-generic/asi.h @@ -0,0 +1,5 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_GENERIC_ASI_H +#define __ASM_GENERIC_ASI_H + +#endif -- 2.45.2.993.g49e7a77208-goog
