kernel/linux.git/arch/arm64/include/asm/scs.h, branch linux-7.0.y

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2025-12-03T01:03:55+00:00

Pull arm64 updates from Catalin Marinas: "These are the arm64 updates for 6.19. The biggest part is the Arm MPAM driver under drivers/resctrl/. There's a patch touching mm/ to handle spurious faults for huge pmd (similar to the pte version). The corresponding arm64 part allows us to avoid the TLB maintenance if a (huge) page is reused after a write fault. There's EFI refactoring to allow runtime services with preemption enabled and the rest is the usual perf/PMU updates and several cleanups/typos. Summary: Core features: - Basic Arm MPAM (Memory system resource Partitioning And Monitoring) driver under drivers/resctrl/ which makes use of the fs/rectrl/ API Perf and PMU: - Avoid cycle counter on multi-threaded CPUs - Extend CSPMU device probing and add additional filtering support for NVIDIA implementations - Add support for the PMUs on the NoC S3 interconnect - Add additional compatible strings for new Cortex and C1 CPUs - Add support for data source filtering to the SPE driver - Add support for i.MX8QM and "DB" PMU in the imx PMU driver Memory managemennt: - Avoid broadcast TLBI if page reused in write fault - Elide TLB invalidation if the old PTE was not valid - Drop redundant cpu_set_*_tcr_t0sz() macros - Propagate pgtable_alloc() errors outside of __create_pgd_mapping() - Propagate return value from __change_memory_common() ACPI and EFI: - Call EFI runtime services without disabling preemption - Remove unused ACPI function Miscellaneous: - ptrace support to disable streaming on SME-only systems - Improve sysreg generation to include a 'Prefix' descriptor - Replace __ASSEMBLY__ with __ASSEMBLER__ - Align register dumps in the kselftest zt-test - Remove some no longer used macros/functions - Various spelling corrections" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (94 commits) arm64/mm: Document why linear map split failure upon vm_reset_perms is not problematic arm64/pageattr: Propagate return value from __change_memory_common arm64/sysreg: Remove unused define ARM64_FEATURE_FIELD_BITS KVM: arm64: selftests: Consider all 7 possible levels of cache KVM: arm64: selftests: Remove ARM64_FEATURE_FIELD_BITS and its last user arm64: atomics: lse: Remove unused parameters from ATOMIC_FETCH_OP_AND macros Documentation/arm64: Fix the typo of register names ACPI: GTDT: Get rid of acpi_arch_timer_mem_init() perf: arm_spe: Add support for filtering on data source perf: Add perf_event_attr::config4 perf/imx_ddr: Add support for PMU in DB (system interconnects) perf/imx_ddr: Get and enable optional clks perf/imx_ddr: Move ida_alloc() from ddr_perf_init() to ddr_perf_probe() dt-bindings: perf: fsl-imx-ddr: Add compatible string for i.MX8QM, i.MX8QXP and i.MX8DXL arm64: remove duplicate ARCH_HAS_MEM_ENCRYPT arm64: mm: use untagged address to calculate page index MAINTAINERS: new entry for MPAM Driver arm_mpam: Add kunit tests for props_mismatch() arm_mpam: Add kunit test for bitmap reset arm_mpam: Add helper to reset saved mbwu state ...

arm64: Replace ASSEMBLY with ASSEMBLER in non-uapi headers

2025-11-11T19:35:59+00:00

While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembly code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This can be very confusing when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So let's standardize now on the __ASSEMBLER__ macro that is provided by the compilers. This is a mostly mechanical patch (done with a simple "sed -i" statement), except for the following files where comments with mis-spelled macros were tweaked manually: arch/arm64/include/asm/stacktrace/frame.h arch/arm64/include/asm/kvm_ptrauth.h arch/arm64/include/asm/debug-monitors.h arch/arm64/include/asm/esr.h arch/arm64/include/asm/scs.h arch/arm64/include/asm/memory.h Signed-off-by: Thomas Huth Signed-off-by: Catalin Marinas

arm64: Fail module loading if dynamic SCS patching fails

2025-11-07T15:00:09+00:00

Disallow a module to load if SCS dynamic patching fails for its code. For module loading, instead of running a dry-run to check for patching errors, try to run patching in the first run and propagate any errors so module loading will fail. Signed-off-by: Adrian Barnaś Reviewed-by: Ard Biesheuvel Signed-off-by: Will Deacon

arm64/scs: Drop unused prototype __pi_scs_patch_vmlinux()

2024-11-08T16:37:55+00:00

The function scs_patch_vmlinux() was removed in the LPA2 boot code refactoring so remove the declaration as well. Signed-off-by: Ard Biesheuvel Reviewed-by: Sami Tolvanen Tested-by: Sami Tolvanen Link: https://lore.kernel.org/r/20241106185513.3096442-8-ardb+git@google.com Signed-off-by: Catalin Marinas

arm64/scs: Fix handling of DWARF augmentation data in CIE/FDE frames

2024-11-08T16:37:55+00:00

The dynamic SCS patching code pretends to parse the DWARF augmentation data in the CIE (header) frame, and handle accordingly when processing the individual FDE frames based on this CIE frame. However, the boolean variable is defined inside the loop, and so the parsed value is ignored. The same applies to the code alignment field, which is also read from the header but then discarded. This was never spotted before because Clang is the only compiler that supports dynamic SCS patching (which is essentially an Android feature), and the unwind tables it produces are highly uniform, and match the de facto defaults. So instead of testing for the 'z' flag in the augmentation data field, require a fixed augmentation data string of 'zR', and simplify the rest of the code accordingly. Also introduce some error codes to specify why the patching failed, and log it to the kernel console on failure when this happens when loading a module. (Doing so for vmlinux is infeasible, as the patching is done extremely early in the boot.) Signed-off-by: Ard Biesheuvel Reviewed-by: Sami Tolvanen Tested-by: Sami Tolvanen Link: https://lore.kernel.org/r/20241106185513.3096442-6-ardb+git@google.com Signed-off-by: Catalin Marinas

arm64: head: Move early kernel mapping routines into C code

2024-02-16T12:42:33+00:00

The asm version of the kernel mapping code works fine for creating a coarse grained identity map, but for mapping the kernel down to its exact boundaries with the right attributes, it is not suitable. This is why we create a preliminary RWX kernel mapping first, and then rebuild it from scratch later on. So let's reimplement this in C, in a way that will make it unnecessary to create the kernel page tables yet another time in paging_init(). Signed-off-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20240214122845.2033971-63-ardb+git@google.com Signed-off-by: Catalin Marinas

arm64: head: move dynamic shadow call stack patching into early C runtime

2024-02-16T12:42:30+00:00

Once we update the early kernel mapping code to only map the kernel once with the right permissions, we can no longer perform code patching via this mapping. So move this code to an earlier stage of the boot, right after applying the relocations. Signed-off-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20240214122845.2033971-54-ardb+git@google.com Signed-off-by: Catalin Marinas

arm64: add scs_patch_vmlinux prototype

2023-05-25T16:44:01+00:00

scs_patch_vmlinux() is only called from assembler code, so there is no prototype, but adding one avoids this warning: arch/arm64/kernel/patch-scs.c:254:24: error: no previous prototype for function 'scs_patch_vmlinux' [-Werror,-Wmissing-prototypes] Signed-off-by: Arnd Bergmann Reviewed-by: Kees Cook Acked-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20230516160642.523862-3-arnd@kernel.org Signed-off-by: Catalin Marinas

arm64: Always load shadow stack pointer directly from the task struct

2023-01-20T14:26:18+00:00

All occurrences of the scs_load macro load the value of the shadow call stack pointer from the task which is current at that point. So instead of taking a task struct register argument in the scs_load macro to specify the task struct to load from, let's always reference the current task directly. This should make it much harder to exploit any instruction sequences reloading the shadow call stack pointer register from memory. Signed-off-by: Ard Biesheuvel Acked-by: Mark Rutland Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20230109174800.3286265-2-ardb@kernel.org Signed-off-by: Catalin Marinas

arm64: implement dynamic shadow call stack for Clang

2022-11-09T18:06:35+00:00

Implement dynamic shadow call stack support on Clang, by parsing the unwind tables at init time to locate all occurrences of PACIASP/AUTIASP instructions, and replacing them with the shadow call stack push and pop instructions, respectively. This is useful because the overhead of the shadow call stack is difficult to justify on hardware that implements pointer authentication (PAC), and given that the PAC instructions are executed as NOPs on hardware that doesn't, we can just replace them without breaking anything. As PACIASP/AUTIASP are guaranteed to be paired with respect to manipulations of the return address, replacing them 1:1 with shadow call stack pushes and pops is guaranteed to result in the desired behavior. Signed-off-by: Ard Biesheuvel Reviewed-by: Sami Tolvanen Tested-by: Sami Tolvanen Link: https://lore.kernel.org/r/20221027155908.1940624-4-ardb@kernel.org Signed-off-by: Will Deacon