kernel.git/arch/arm64/kernel/Makefile, branch linux-5.13.y

arm64: entry: fix KCOV suppression

2021-07-28T12:37:42Z

commit e6f85cbeb23bd74b8966cf1f15bf7d01399ff625 upstream. We suppress KCOV for entry.o rather than entry-common.o. As entry.o is built from entry.S, this is pointless, and permits instrumentation of entry-common.o, which is built from entry-common.c. Fix the Makefile to suppress KCOV for entry-common.o, as we had intended to begin with. I've verified with objdump that this is working as expected. Fixes: bf6fa2c0dda7 ("arm64: entry: don't instrument entry code with KCOV") Signed-off-by: Mark Rutland Cc: Catalin Marinas Cc: James Morse Cc: Marc Zyngier Cc: Will Deacon Link: https://lore.kernel.org/r/20210715123049.9990-1-mark.rutland@arm.com Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

arm64: entry: don't instrument entry code with KCOV

2021-07-14T15:06:25Z

[ Upstream commit bf6fa2c0dda751863c3446aa64d733013bec4a19 ] The code in entry-common.c runs at exception entry and return boundaries, where portions of the kernel environment aren't available. For example, RCU may not be watching, and lockdep state may be out-of-sync with the hardware. Due to this, it is not sound to instrument this code. We generally avoid instrumentation by marking the entry functions as `noinstr`, but currently this doesn't inhibit KCOV instrumentation. Prevent this by disabling KCOV for the entire compilation unit. Signed-off-by: Mark Rutland Acked-by: Catalin Marinas Acked-by: Marc Zyngier Cc: James Morse Cc: Will Deacon Link: https://lore.kernel.org/r/20210607094624.34689-20-mark.rutland@arm.com Signed-off-by: Will Deacon Signed-off-by: Sasha Levin

arm64: entry: Enable random_kstack_offset support

2021-04-08T12:12:19Z

Allow for a randomized stack offset on a per-syscall basis, with roughly 5 bits of entropy. (And include AAPCS rationale AAPCS thanks to Mark Rutland.) In order to avoid unconditional stack canaries on syscall entry (due to the use of alloca()), also disable stack protector to avoid triggering needless checks and slowing down the entry path. As there is no general way to control stack protector coverage with a function attribute[1], this must be disabled at the compilation unit level. This isn't a problem here, though, since stack protector was not triggered before: examining the resulting syscall.o, there are no changes in canary coverage (none before, none now). [1] a working __attribute__((no_stack_protector)) has been added to GCC and Clang but has not been released in any version yet: https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=346b302d09c1e6db56d9fe69048acb32fbb97845 https://reviews.llvm.org/rG4fbf84c1732fca596ad1d6e96015e19760eb8a9b Signed-off-by: Kees Cook Signed-off-by: Thomas Gleixner Acked-by: Will Deacon Link: https://lore.kernel.org/r/20210401232347.2791257-6-keescook@chromium.org

Merge branch 'for-next/vdso' into for-next/core

2021-02-12T15:17:42Z

vDSO build improvements. * for-next/vdso: arm64: Support running gen_vdso_offsets.sh with BSD userland. arm64: do not descend to vdso directories twice

arm64: cpufeature: Add an early command-line cpufeature override facility

2021-02-09T13:50:52Z

In order to be able to override CPU features at boot time, let's add a command line parser that matches options of the form "cpureg.feature=value", and store the corresponding value into the override val/mask pair. No features are currently defined, so no expected change in functionality. Signed-off-by: Marc Zyngier Acked-by: David Brazdil Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20210208095732.3267263-14-maz@kernel.org Signed-off-by: Will Deacon

arm64: do not descend to vdso directories twice

2021-01-20T12:18:46Z

arm64 descends into each vdso directory twice; first in vdso_prepare, second during the ordinary build process. PPC mimicked it and uncovered a problem [1]. In the first descend, Kbuild directly visits the vdso directories, therefore it does not inherit subdir-ccflags-y from upper directories. This means the command line parameters may differ between the two. If it happens, the offset values in the generated headers might be different from real offsets of vdso.so in the kernel. This potential danger should be avoided. The vdso directories are built in the vdso_prepare stage, so the second descend is unneeded. [1]: https://lore.kernel.org/linux-kbuild/CAK7LNARAkJ3_-4gX0VA2UkapbOftuzfSTVMBbgbw=HD8n7N+7w@mail.gmail.com/T/#ma10dcb961fda13f36d42d58fa6cb2da988b7e73a Signed-off-by: Masahiro Yamada Link: https://lore.kernel.org/r/20201218024540.1102650-1-masahiroy@kernel.org Signed-off-by: Will Deacon

arm64: scs: use vmapped IRQ and SDEI shadow stacks

2020-12-01T11:23:34Z

Use scs_alloc() to allocate also IRQ and SDEI shadow stacks instead of using statically allocated stacks. Signed-off-by: Sami Tolvanen Acked-by: Will Deacon Link: https://lore.kernel.org/r/20201130233442.2562064-3-samitolvanen@google.com [will: Move CONFIG_SHADOW_CALL_STACK check into init_irq_scs()] Signed-off-by: Will Deacon

Merge branch 'for-next/mte' into for-next/core

2020-10-02T11:16:11Z

Add userspace support for the Memory Tagging Extension introduced by Armv8.5. (Catalin Marinas and others) * for-next/mte: (30 commits) arm64: mte: Fix typo in memory tagging ABI documentation arm64: mte: Add Memory Tagging Extension documentation arm64: mte: Kconfig entry arm64: mte: Save tags when hibernating arm64: mte: Enable swap of tagged pages mm: Add arch hooks for saving/restoring tags fs: Handle intra-page faults in copy_mount_options() arm64: mte: ptrace: Add NT_ARM_TAGGED_ADDR_CTRL regset arm64: mte: ptrace: Add PTRACE_{PEEK,POKE}MTETAGS support arm64: mte: Allow {set,get}_tagged_addr_ctrl() on non-current tasks arm64: mte: Restore the GCR_EL1 register after a suspend arm64: mte: Allow user control of the generated random tags via prctl() arm64: mte: Allow user control of the tag check mode via prctl() mm: Allow arm64 mmap(PROT_MTE) on RAM-based files arm64: mte: Validate the PROT_MTE request via arch_validate_flags() mm: Introduce arch_validate_flags() arm64: mte: Add PROT_MTE support to mmap() and mprotect() mm: Introduce arch_calc_vm_flag_bits() arm64: mte: Tags-aware aware memcmp_pages() implementation arm64: Avoid unnecessary clear_user_page() indirection ...

Merge branch 'for-next/ghostbusters' into for-next/core

2020-10-02T11:15:24Z

Fix and subsequently rewrite Spectre mitigations, including the addition of support for PR_SPEC_DISABLE_NOEXEC. (Will Deacon and Marc Zyngier) * for-next/ghostbusters: (22 commits) arm64: Add support for PR_SPEC_DISABLE_NOEXEC prctl() option arm64: Pull in task_stack_page() to Spectre-v4 mitigation code KVM: arm64: Allow patching EL2 vectors even with KASLR is not enabled arm64: Get rid of arm64_ssbd_state KVM: arm64: Convert ARCH_WORKAROUND_2 to arm64_get_spectre_v4_state() KVM: arm64: Get rid of kvm_arm_have_ssbd() KVM: arm64: Simplify handling of ARCH_WORKAROUND_2 arm64: Rewrite Spectre-v4 mitigation code arm64: Move SSBD prctl() handler alongside other spectre mitigation code arm64: Rename ARM64_SSBD to ARM64_SPECTRE_V4 arm64: Treat SSBS as a non-strict system feature arm64: Group start_thread() functions together KVM: arm64: Set CSV2 for guests on hardware unaffected by Spectre-v2 arm64: Rewrite Spectre-v2 mitigation code arm64: Introduce separate file for spectre mitigations and reporting arm64: Rename ARM64_HARDEN_BRANCH_PREDICTOR to ARM64_SPECTRE_V2 KVM: arm64: Simplify install_bp_hardening_cb() KVM: arm64: Replace CONFIG_KVM_INDIRECT_VECTORS with CONFIG_RANDOMIZE_BASE arm64: Remove Spectre-related CONFIG_* options arm64: Run ARCH_WORKAROUND_2 enabling code on all CPUs ...

arm64: Move SSBD prctl() handler alongside other spectre mitigation code

2020-09-29T15:08:16Z

As part of the spectre consolidation effort to shift all of the ghosts into their own proton pack, move all of the horrible SSBD prctl() code out of its own 'ssbd.c' file. Signed-off-by: Will Deacon