diff options
116 files changed, 1353 insertions, 4425 deletions
diff --git a/Documentation/powerpc/dexcr.rst b/Documentation/powerpc/dexcr.rst new file mode 100644 index 000000000000..615a631f51fa --- /dev/null +++ b/Documentation/powerpc/dexcr.rst @@ -0,0 +1,58 @@ +.. SPDX-License-Identifier: GPL-2.0-or-later + +========================================== +DEXCR (Dynamic Execution Control Register) +========================================== + +Overview +======== + +The DEXCR is a privileged special purpose register (SPR) introduced in +PowerPC ISA 3.1B (Power10) that allows per-cpu control over several dynamic +execution behaviours. These behaviours include speculation (e.g., indirect +branch target prediction) and enabling return-oriented programming (ROP) +protection instructions. + +The execution control is exposed in hardware as up to 32 bits ('aspects') in +the DEXCR. Each aspect controls a certain behaviour, and can be set or cleared +to enable/disable the aspect. There are several variants of the DEXCR for +different purposes: + +DEXCR + A privileged SPR that can control aspects for userspace and kernel space +HDEXCR + A hypervisor-privileged SPR that can control aspects for the hypervisor and + enforce aspects for the kernel and userspace. +UDEXCR + An optional ultravisor-privileged SPR that can control aspects for the ultravisor. + +Userspace can examine the current DEXCR state using a dedicated SPR that +provides a non-privileged read-only view of the userspace DEXCR aspects. +There is also an SPR that provides a read-only view of the hypervisor enforced +aspects, which ORed with the userspace DEXCR view gives the effective DEXCR +state for a process. + + +Configuration +============= + +The DEXCR is currently unconfigurable. All threads are run with the +NPHIE aspect enabled. + + +coredump and ptrace +=================== + +The userspace values of the DEXCR and HDEXCR (in this order) are exposed under +``NT_PPC_DEXCR``. These are each 64 bits and readonly, and are intended to +assist with core dumps. The DEXCR may be made writable in future. The top 32 +bits of both registers (corresponding to the non-userspace bits) are masked off. + +If the kernel config ``CONFIG_CHECKPOINT_RESTORE`` is enabled, then +``NT_PPC_HASHKEYR`` is available and exposes the HASHKEYR value of the process +for reading and writing. This is a tradeoff between increased security and +checkpoint/restore support: a process should normally have no need to know its +secret key, but restoring a process requires setting its original key. The key +therefore appears in core dumps, and an attacker may be able to retrieve it from +a coredump and effectively bypass ROP protection on any threads that share this +key (potentially all threads from the same parent that have not run ``exec()``). diff --git a/Documentation/powerpc/index.rst b/Documentation/powerpc/index.rst index 85e80e30160b..d33b554ca7ba 100644 --- a/Documentation/powerpc/index.rst +++ b/Documentation/powerpc/index.rst @@ -15,6 +15,7 @@ powerpc cxl cxlflash dawr-power9 + dexcr dscr eeh-pci-error-recovery elf_hwcaps diff --git a/MAINTAINERS b/MAINTAINERS index e0976ae2a523..96e4a0dd3a6f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -11448,7 +11448,13 @@ F: arch/mips/include/uapi/asm/kvm* F: arch/mips/kvm/ KERNEL VIRTUAL MACHINE FOR POWERPC (KVM/powerpc) +M: Michael Ellerman <mpe@ellerman.id.au> +R: Nicholas Piggin <npiggin@gmail.com> L: linuxppc-dev@lists.ozlabs.org +L: kvm@vger.kernel.org +S: Maintained (Book3S 64-bit HV) +S: Odd fixes (Book3S 64-bit PR) +S: Orphan (Book3E and 32-bit) T: git git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git topic/ppc-kvm F: arch/powerpc/include/asm/kvm* F: arch/powerpc/include/uapi/asm/kvm* @@ -11981,11 +11987,12 @@ F: lib/linear_ranges.c F: lib/test_linear_ranges.c LINUX FOR POWER MACINTOSH -M: Benjamin Herrenschmidt <benh@kernel.crashing.org> L: linuxppc-dev@lists.ozlabs.org -S: Odd Fixes +S: Orphan F: arch/powerpc/platforms/powermac/ F: drivers/macintosh/ +X: drivers/macintosh/adb-iop.c +X: drivers/macintosh/via-macii.c LINUX FOR POWERPC (32-BIT AND 64-BIT) M: Michael Ellerman <mpe@ellerman.id.au> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 395044b705a1..0b1172cbeccb 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -210,7 +210,7 @@ config PPC select HAVE_ARCH_KASAN if PPC_RADIX_MMU select HAVE_ARCH_KASAN if PPC_BOOK3E_64 select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN - select HAVE_ARCH_KCSAN if PPC_BOOK3S_64 + select HAVE_ARCH_KCSAN select HAVE_ARCH_KFENCE if ARCH_SUPPORTS_DEBUG_PAGEALLOC select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET select HAVE_ARCH_WITHIN_STACK_FRAMES @@ -235,7 +235,7 @@ config PPC select HAVE_FUNCTION_DESCRIPTORS if PPC64_ELF_ABI_V1 select HAVE_FUNCTION_ERROR_INJECTION select HAVE_FUNCTION_GRAPH_TRACER - select HAVE_FUNCTION_TRACER + select HAVE_FUNCTION_TRACER if PPC64 || (PPC32 && CC_IS_GCC) select HAVE_GCC_PLUGINS if GCC_VERSION >= 50200 # plugin support on gcc <= 5.1 is buggy on PPC select HAVE_GENERIC_VDSO select HAVE_HARDLOCKUP_DETECTOR_ARCH if PPC_BOOK3S_64 && SMP @@ -547,8 +547,9 @@ config LD_HEAD_STUB_CATCH If unsure, say "N". config MPROFILE_KERNEL - depends on PPC64 && CPU_LITTLE_ENDIAN && FUNCTION_TRACER - def_bool $(success,$(srctree)/arch/powerpc/tools/gcc-check-mprofile-kernel.sh $(CC) -I$(srctree)/include -D__KERNEL__) + depends on PPC64_ELF_ABI_V2 && FUNCTION_TRACER + def_bool $(success,$(srctree)/arch/powerpc/tools/gcc-check-mprofile-kernel.sh $(CC) -mlittle-endian) if CPU_LITTLE_ENDIAN + def_bool $(success,$(srctree)/arch/powerpc/tools/gcc-check-mprofile-kernel.sh $(CC) -mbig-endian) if CPU_BIG_ENDIAN config HOTPLUG_CPU bool "Support for enabling/disabling CPUs" @@ -624,10 +625,12 @@ config ARCH_HAS_KEXEC_PURGATORY def_bool KEXEC_FILE config |