summaryrefslogtreecommitdiff
path: root/arch/arm64/kernel/traps.c
AgeCommit message (Collapse)Author
2023-11-02Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "ARM: - Generalized infrastructure for 'writable' ID registers, effectively allowing userspace to opt-out of certain vCPU features for its guest - Optimization for vSGI injection, opportunistically compressing MPIDR to vCPU mapping into a table - Improvements to KVM's PMU emulation, allowing userspace to select the number of PMCs available to a VM - Guest support for memory operation instructions (FEAT_MOPS) - Cleanups to handling feature flags in KVM_ARM_VCPU_INIT, squashing bugs and getting rid of useless code - Changes to the way the SMCCC filter is constructed, avoiding wasted memory allocations when not in use - Load the stage-2 MMU context at vcpu_load() for VHE systems, reducing the overhead of errata mitigations - Miscellaneous kernel and selftest fixes LoongArch: - New architecture for kvm. The hardware uses the same model as x86, s390 and RISC-V, where guest/host mode is orthogonal to supervisor/user mode. The virtualization extensions are very similar to MIPS, therefore the code also has some similarities but it's been cleaned up to avoid some of the historical bogosities that are found in arch/mips. The kernel emulates MMU, timer and CSR accesses, while interrupt controllers are only emulated in userspace, at least for now. RISC-V: - Support for the Smstateen and Zicond extensions - Support for virtualizing senvcfg - Support for virtualized SBI debug console (DBCN) S390: - Nested page table management can be monitored through tracepoints and statistics x86: - Fix incorrect handling of VMX posted interrupt descriptor in KVM_SET_LAPIC, which could result in a dropped timer IRQ - Avoid WARN on systems with Intel IPI virtualization - Add CONFIG_KVM_MAX_NR_VCPUS, to allow supporting up to 4096 vCPUs without forcing more common use cases to eat the extra memory overhead. - Add virtualization support for AMD SRSO mitigation (IBPB_BRTYPE and SBPB, aka Selective Branch Predictor Barrier). - Fix a bug where restoring a vCPU snapshot that was taken within 1 second of creating the original vCPU would cause KVM to try to synchronize the vCPU's TSC and thus clobber the correct TSC being set by userspace. - Compute guest wall clock using a single TSC read to avoid generating an inaccurate time, e.g. if the vCPU is preempted between multiple TSC reads. - "Virtualize" HWCR.TscFreqSel to make Linux guests happy, which complain about a "Firmware Bug" if the bit isn't set for select F/M/S combos. Likewise "virtualize" (ignore) MSR_AMD64_TW_CFG to appease Windows Server 2022. - Don't apply side effects to Hyper-V's synthetic timer on writes from userspace to fix an issue where the auto-enable behavior can trigger spurious interrupts, i.e. do auto-enabling only for guest writes. - Remove an unnecessary kick of all vCPUs when synchronizing the dirty log without PML enabled. - Advertise "support" for non-serializing FS/GS base MSR writes as appropriate. - Harden the fast page fault path to guard against encountering an invalid root when walking SPTEs. - Omit "struct kvm_vcpu_xen" entirely when CONFIG_KVM_XEN=n. - Use the fast path directly from the timer callback when delivering Xen timer events, instead of waiting for the next iteration of the run loop. This was not done so far because previously proposed code had races, but now care is taken to stop the hrtimer at critical points such as restarting the timer or saving the timer information for userspace. - Follow the lead of upstream Xen and ignore the VCPU_SSHOTTMR_future flag. - Optimize injection of PMU interrupts that are simultaneous with NMIs. - Usual handful of fixes for typos and other warts. x86 - MTRR/PAT fixes and optimizations: - Clean up code that deals with honoring guest MTRRs when the VM has non-coherent DMA and host MTRRs are ignored, i.e. EPT is enabled. - Zap EPT entries when non-coherent DMA assignment stops/start to prevent using stale entries with the wrong memtype. - Don't ignore guest PAT for CR0.CD=1 && KVM_X86_QUIRK_CD_NW_CLEARED=y This was done as a workaround for virtual machine BIOSes that did not bother to clear CR0.CD (because ancient KVM/QEMU did not bother to set it, in turn), and there's zero reason to extend the quirk to also ignore guest PAT. x86 - SEV fixes: - Report KVM_EXIT_SHUTDOWN instead of EINVAL if KVM intercepts SHUTDOWN while running an SEV-ES guest. - Clean up the recognition of emulation failures on SEV guests, when KVM would like to "skip" the instruction but it had already been partially emulated. This makes it possible to drop a hack that second guessed the (insufficient) information provided by the emulator, and just do the right thing. Documentation: - Various updates and fixes, mostly for x86 - MTRR and PAT fixes and optimizations" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (164 commits) KVM: selftests: Avoid using forced target for generating arm64 headers tools headers arm64: Fix references to top srcdir in Makefile KVM: arm64: Add tracepoint for MMIO accesses where ISV==0 KVM: arm64: selftest: Perform ISB before reading PAR_EL1 KVM: arm64: selftest: Add the missing .guest_prepare() KVM: arm64: Always invalidate TLB for stage-2 permission faults KVM: x86: Service NMI requests after PMI requests in VM-Enter path KVM: arm64: Handle AArch32 SPSR_{irq,abt,und,fiq} as RAZ/WI KVM: arm64: Do not let a L1 hypervisor access the *32_EL2 sysregs KVM: arm64: Refine _EL2 system register list that require trap reinjection arm64: Add missing _EL2 encodings arm64: Add missing _EL12 encodings KVM: selftests: aarch64: vPMU test for validating user accesses KVM: selftests: aarch64: vPMU register test for unimplemented counters KVM: selftests: aarch64: vPMU register test for implemented counters KVM: selftests: aarch64: Introduce vpmu_counter_access test tools: Import arm_pmuv3.h KVM: arm64: PMU: Allow userspace to limit PMCR_EL0.N for the guest KVM: arm64: Sanitize PM{C,I}NTEN{SET,CLR}, PMOVS{SET,CLR} before first run KVM: arm64: Add {get,set}_user for PM{C,I}NTEN{SET,CLR}, PMOVS{SET,CLR} ...
2023-10-16arm64: Avoid cpus_have_const_cap() for ARM64_WORKAROUND_1542419Mark Rutland
We use cpus_have_const_cap() to check for ARM64_WORKAROUND_1542419 but this is not necessary and cpus_have_final_cap() would be preferable. For historical reasons, cpus_have_const_cap() is more complicated than it needs to be. Before cpucaps are finalized, it will perform a bitmap test of the system_cpucaps bitmap, and once cpucaps are finalized it will use an alternative branch. This used to be necessary to handle some race conditions in the window between cpucap detection and the subsequent patching of alternatives and static branches, where different branches could be out-of-sync with one another (or w.r.t. alternative sequences). Now that we use alternative branches instead of static branches, these are all patched atomically w.r.t. one another, and there are only a handful of cases that need special care in the window between cpucap detection and alternative patching. Due to the above, it would be nice to remove cpus_have_const_cap(), and migrate callers over to alternative_has_cap_*(), cpus_have_final_cap(), or cpus_have_cap() depending on when their requirements. This will remove redundant instructions and improve code generation, and will make it easier to determine how each callsite will behave before, during, and after alternative patching. The ARM64_WORKAROUND_1542419 cpucap is detected and patched before any userspace code can run, and the both __do_compat_cache_op() and ctr_read_handler() are only reachable from exceptions taken from userspace. Thus it is not necessary for either to use cpus_have_const_cap(), and cpus_have_final_cap() is equivalent. This patch replaces the use of cpus_have_const_cap() with cpus_have_final_cap(), which will avoid generating code to test the system_cpucaps bitmap and should be better for all subsequent calls at runtime. Using cpus_have_final_cap() clearly documents that we do not expect this code to run before cpucaps are finalized, and will make it easier to spot issues if code is changed in future to allow these functions to be reached earlier. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-10-09KVM: arm64: Add handler for MOPS exceptionsKristina Martsenko
An Armv8.8 FEAT_MOPS main or epilogue instruction will take an exception if executed on a CPU with a different MOPS implementation option (A or B) than the CPU where the preceding prologue instruction ran. In this case the OS exception handler is expected to reset the registers and restart execution from the prologue instruction. A KVM guest may use the instructions at EL1 at times when the guest is not able to handle the exception, expecting that the instructions will only run on one CPU (e.g. when running UEFI boot services in the guest). As KVM may reschedule the guest between different types of CPUs at any time (on an asymmetric system), it needs to also handle the resulting exception itself in case the guest is not able to. A similar situation will also occur in the future when live migrating a guest from one type of CPU to another. Add handling for the MOPS exception to KVM. The handling can be shared with the EL0 exception handler, as the logic and register layouts are the same. The exception can be handled right after exiting a guest, which avoids the cost of returning to the host exit handler. Similarly to the EL0 exception handler, in case the main or epilogue instruction is being single stepped, it makes sense to finish the step before executing the prologue instruction, so advance the single step state machine. Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230922112508.1774352-2-kristina.martsenko@arm.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-28Merge tag 'mm-stable-2023-06-24-19-15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull mm updates from Andrew Morton: - Yosry Ahmed brought back some cgroup v1 stats in OOM logs - Yosry has also eliminated cgroup's atomic rstat flushing - Nhat Pham adds the new cachestat() syscall. It provides userspace with the ability to query pagecache status - a similar concept to mincore() but more powerful and with improved usability - Mel Gorman provides more optimizations for compaction, reducing the prevalence of page rescanning - Lorenzo Stoakes has done some maintanance work on the get_user_pages() interface - Liam Howlett continues with cleanups and maintenance work to the maple tree code. Peng Zhang also does some work on maple tree - Johannes Weiner has done some cleanup work on the compaction code - David Hildenbrand has contributed additional selftests for get_user_pages() - Thomas Gleixner has contributed some maintenance and optimization work for the vmalloc code - Baolin Wang has provided some compaction cleanups, - SeongJae Park continues maintenance work on the DAMON code - Huang Ying has done some maintenance on the swap code's usage of device refcounting - Christoph Hellwig has some cleanups for the filemap/directio code - Ryan Roberts provides two patch series which yield some rationalization of the kernel's access to pte entries - use the provided APIs rather than open-coding accesses - Lorenzo Stoakes has some fixes to the interaction between pagecache and directio access to file mappings - John Hubbard has a series of fixes to the MM selftesting code - ZhangPeng continues the folio conversion campaign - Hugh Dickins has been working on the pagetable handling code, mainly with a view to reducing the load on the mmap_lock - Catalin Marinas has reduced the arm64 kmalloc() minimum alignment from 128 to 8 - Domenico Cerasuolo has improved the zswap reclaim mechanism by reorganizing the LRU management - Matthew Wilcox provides some fixups to make gfs2 work better with the buffer_head code - Vishal Moola also has done some folio conversion work - Matthew Wilcox has removed the remnants of the pagevec code - their functionality is migrated over to struct folio_batch * tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (380 commits) mm/hugetlb: remove hugetlb_set_page_subpool() mm: nommu: correct the range of mmap_sem_read_lock in task_mem() hugetlb: revert use of page_cache_next_miss() Revert "page cache: fix page_cache_next/prev_miss off by one" mm/vmscan: fix root proactive reclaim unthrottling unbalanced node mm: memcg: rename and document global_reclaim() mm: kill [add|del]_page_to_lru_list() mm: compaction: convert to use a folio in isolate_migratepages_block() mm: zswap: fix double invalidate with exclusive loads mm: remove unnecessary pagevec includes mm: remove references to pagevec mm: rename invalidate_mapping_pagevec to mapping_try_invalidate mm: remove struct pagevec net: convert sunrpc from pagevec to folio_batch i915: convert i915_gpu_error to use a folio_batch pagevec: rename fbatch_count() mm: remove check_move_unevictable_pages() drm: convert drm_gem_put_pages() to use a folio_batch i915: convert shmem_sg_free_table() to use a folio_batch scatterlist: add sg_set_folio() ...
2023-06-23Merge branches 'for-next/kpti', 'for-next/missing-proto-warn', ↵Catalin Marinas
'for-next/iss2-decode', 'for-next/kselftest', 'for-next/misc', 'for-next/feat_mops', 'for-next/module-alloc', 'for-next/sysreg', 'for-next/cpucap', 'for-next/acpi', 'for-next/kdump', 'for-next/acpi-doc', 'for-next/doc' and 'for-next/tpidr2-fix', remote-tracking branch 'arm64/for-next/perf' into for-next/core * arm64/for-next/perf: docs: perf: Fix warning from 'make htmldocs' in hisi-pmu.rst docs: perf: Add new description for HiSilicon UC PMU drivers/perf: hisi: Add support for HiSilicon UC PMU driver drivers/perf: hisi: Add support for HiSilicon H60PA and PAv3 PMU driver perf: arm_cspmu: Add missing MODULE_DEVICE_TABLE perf/arm-cmn: Add sysfs identifier perf/arm-cmn: Revamp model detection perf/arm_dmc620: Add cpumask dt-bindings: perf: fsl-imx-ddr: Add i.MX93 compatible drivers/perf: imx_ddr: Add support for NXP i.MX9 SoC DDRC PMU driver perf/arm_cspmu: Decouple APMT dependency perf/arm_cspmu: Clean up ACPI dependency ACPI/APMT: Don't register invalid resource perf/arm_cspmu: Fix event attribute type perf: arm_cspmu: Set irq affinitiy only if overflow interrupt is used drivers/perf: hisi: Don't migrate perf to the CPU going to teardown drivers/perf: apple_m1: Force 63bit counters for M2 CPUs perf/arm-cmn: Fix DTC reset perf: qcom_l2_pmu: Make l2_cache_pmu_probe_cluster() more robust perf/arm-cci: Slightly optimize cci_pmu_sync_counters() * for-next/kpti: : Simplify KPTI trampoline exit code arm64: entry: Simplify tramp_alias macro and tramp_exit routine arm64: entry: Preserve/restore X29 even for compat tasks * for-next/missing-proto-warn: : Address -Wmissing-prototype warnings arm64: add alt_cb_patch_nops prototype arm64: move early_brk64 prototype to header arm64: signal: include asm/exception.h arm64: kaslr: add kaslr_early_init() declaration arm64: flush: include linux/libnvdimm.h arm64: module-plts: inline linux/moduleloader.h arm64: hide unused is_valid_bugaddr() arm64: efi: add efi_handle_corrupted_x18 prototype arm64: cpuidle: fix #ifdef for acpi functions arm64: kvm: add prototypes for functions called in asm arm64: spectre: provide prototypes for internal functions arm64: move cpu_suspend_set_dbg_restorer() prototype to header arm64: avoid prototype warnings for syscalls arm64: add scs_patch_vmlinux prototype arm64: xor-neon: mark xor_arm64_neon_*() static * for-next/iss2-decode: : Add decode of ISS2 to data abort reports arm64/esr: Add decode of ISS2 to data abort reporting arm64/esr: Use GENMASK() for the ISS mask * for-next/kselftest: : Various arm64 kselftest improvements kselftest/arm64: Log signal code and address for unexpected signals kselftest/arm64: Add a smoke test for ptracing hardware break/watch points * for-next/misc: : Miscellaneous patches arm64: alternatives: make clean_dcache_range_nopatch() noinstr-safe arm64: hibernate: remove WARN_ON in save_processor_state arm64/fpsimd: Exit streaming mode when flushing tasks arm64: mm: fix VA-range sanity check arm64/mm: remove now-superfluous ISBs from TTBR writes arm64: consolidate rox page protection logic arm64: set __exception_irq_entry with __irq_entry as a default arm64: syscall: unmask DAIF for tracing status arm64: lockdep: enable checks for held locks when returning to userspace arm64/cpucaps: increase string width to properly format cpucaps.h arm64/cpufeature: Use helper for ECV CNTPOFF cpufeature * for-next/feat_mops: : Support for ARMv8.8 memcpy instructions in userspace kselftest/arm64: add MOPS to hwcap test arm64: mops: allow disabling MOPS from the kernel command line arm64: mops: detect and enable FEAT_MOPS arm64: mops: handle single stepping after MOPS exception arm64: mops: handle MOPS exceptions KVM: arm64: hide MOPS from guests arm64: mops: don't disable host MOPS instructions from EL2 arm64: mops: document boot requirements for MOPS KVM: arm64: switch HCRX_EL2 between host and guest arm64: cpufeature: detect FEAT_HCX KVM: arm64: initialize HCRX_EL2 * for-next/module-alloc: : Make the arm64 module allocation code more robust (clean-up, VA range expansion) arm64: module: rework module VA range selection arm64: module: mandate MODULE_PLTS arm64: module: move module randomization to module.c arm64: kaslr: split kaslr/module initialization arm64: kasan: remove !KASAN_VMALLOC remnants arm64: module: remove old !KASAN_VMALLOC logic * for-next/sysreg: (21 commits) : More sysreg conversions to automatic generation arm64/sysreg: Convert TRBIDR_EL1 register to automatic generation arm64/sysreg: Convert TRBTRG_EL1 register to automatic generation arm64/sysreg: Convert TRBMAR_EL1 register to automatic generation arm64/sysreg: Convert TRBSR_EL1 register to automatic generation arm64/sysreg: Convert TRBBASER_EL1 register to automatic generation arm64/sysreg: Convert TRBPTR_EL1 register to automatic generation arm64/sysreg: Convert TRBLIMITR_EL1 register to automatic generation arm64/sysreg: Rename TRBIDR_EL1 fields per auto-gen tools format arm64/sysreg: Rename TRBTRG_EL1 fields per auto-gen tools format arm64/sysreg: Rename TRBMAR_EL1 fields per auto-gen tools format arm64/sysreg: Rename TRBSR_EL1 fields per auto-gen tools format arm64/sysreg: Rename TRBBASER_EL1 fields per auto-gen tools format arm64/sysreg: Rename TRBPTR_EL1 fields per auto-gen tools format arm64/sysreg: Rename TRBLIMITR_EL1 fields per auto-gen tools format arm64/sysreg: Convert OSECCR_EL1 to automatic generation arm64/sysreg: Convert OSDTRTX_EL1 to automatic generation arm64/sysreg: Convert OSDTRRX_EL1 to automatic generation arm64/sysreg: Convert OSLAR_EL1 to automatic generation arm64/sysreg: Standardise naming of bitfield constants in OSL[AS]R_EL1 arm64/sysreg: Convert MDSCR_EL1 to automatic register generation ... * for-next/cpucap: : arm64 cpucap clean-up arm64: cpufeature: fold cpus_set_cap() into update_cpu_capabilities() arm64: cpufeature: use cpucap naming arm64: alternatives: use cpucap naming arm64: standardise cpucap bitmap names * for-next/acpi: : Various arm64-related ACPI patches ACPI: bus: Consolidate all arm specific initialisation into acpi_arm_init() * for-next/kdump: : Simplify the crashkernel reservation behaviour of crashkernel=X,high on arm64 arm64: add kdump.rst into index.rst Documentation: add kdump.rst to present crashkernel reservation on arm64 arm64: kdump: simplify the reservation behaviour of crashkernel=,high * for-next/acpi-doc: : Update ACPI documentation for Arm systems Documentation/arm64: Update ACPI tables from BBR Documentation/arm64: Update references in arm-acpi Documentation/arm64: Update ARM and arch reference * for-next/doc: : arm64 documentation updates Documentation/arm64: Add ptdump documentation * for-next/tpidr2-fix: : Fix the TPIDR2_EL0 register restoring on sigreturn kselftest/arm64: Add a test case for TPIDR2 restore arm64/signal: Restore TPIDR2 register rather than memory state
2023-06-09kasan: use internal prototypes matching gcc-13 builtinsArnd Bergmann
gcc-13 warns about function definitions for builtin interfaces that have a different prototype, e.g.: In file included from kasan_test.c:31: kasan.h:574:6: error: conflicting types for built-in function '__asan_register_globals'; expected 'void(void *, long int)' [-Werror=builtin-declaration-mismatch] 574 | void __asan_register_globals(struct kasan_global *globals, size_t size); kasan.h:577:6: error: conflicting types for built-in function '__asan_alloca_poison'; expected 'void(void *, long int)' [-Werror=builtin-declaration-mismatch] 577 | void __asan_alloca_poison(unsigned long addr, size_t size); kasan.h:580:6: error: conflicting types for built-in function '__asan_load1'; expected 'void(void *)' [-Werror=builtin-declaration-mismatch] 580 | void __asan_load1(unsigned long addr); kasan.h:581:6: error: conflicting types for built-in function '__asan_store1'; expected 'void(void *)' [-Werror=builtin-declaration-mismatch] 581 | void __asan_store1(unsigned long addr); kasan.h:643:6: error: conflicting types for built-in function '__hwasan_tag_memory'; expected 'void(void *, unsigned char, long int)' [-Werror=builtin-declaration-mismatch] 643 | void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size); The two problems are: - Addresses are passes as 'unsigned long' in the kernel, but gcc-13 expects a 'void *'. - sizes meant to use a signed ssize_t rather than size_t. Change all the prototypes to match these. Using 'void *' consistently for addresses gets rid of a couple of type casts, so push that down to the leaf functions where possible. This now passes all randconfig builds on arm, arm64 and x86, but I have not tested it on the other architectures that support kasan, since they tend to fail randconfig builds in other ways. This might fail if any of the 32-bit architectures expect a 'long' instead of 'int' for the size argument. The __asan_allocas_unpoison() function prototype is somewhat weird, since it uses a pointer for 'stack_top' and an size_t for 'stack_bottom'. This looks like it is meant to be 'addr' and 'size' like the others, but the implementation clearly treats them as 'top' and 'bottom'. Link: https://lkml.kernel.org/r/20230509145735.9263-2-arnd@kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Marco Elver <elver@google.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-05arm64: mops: handle single stepping after MOPS exceptionKristina Martsenko
When a MOPS main or epilogue instruction is being executed, the task may get scheduled on a different CPU and restart execution from the prologue instruction. If the main or epilogue instruction is being single stepped then it makes sense to finish the step and take the step exception before starting to execute the next (prologue) instruction. So fast-forward the single step state machine when taking a MOPS exception. This means that if a main or epilogue instruction is single stepped with ptrace, the debugger will sometimes observe the PC moving back to the prologue instruction. (As already mentioned, this should be rare as it only happens when the task is scheduled to another CPU during the step.) This also ensures that perf breakpoints count prologue instructions consistently (i.e. every time they are executed), rather than skipping them when there also happens to be a breakpoint on a main or epilogue instruction. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20230509142235.3284028-9-kristina.martsenko@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-05arm64: mops: handle MOPS exceptionsKristina Martsenko
The memory copy/set instructions added as part of FEAT_MOPS can take an exception (e.g. page fault) part-way through their execution and resume execution afterwards. If however the task is re-scheduled and execution resumes on a different CPU, then the CPU may take a new type of exception to indicate this. This is because the architecture allows two options (Option A and Option B) to implement the instructions and a heterogeneous system can have different implementations between CPUs. In this case the OS has to reset the registers and restart execution from the prologue instruction. The algorithm for doing this is provided as part of the Arm ARM. Add an exception handler for the new exception and wire it up for userspace tasks. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20230509142235.3284028-8-kristina.martsenko@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-05-25arm64: hide unused is_valid_bugaddr()Arnd Bergmann
When generic BUG() support is disabled, this function has no declaration and no callers but causes a W=1 warning: arch/arm64/kernel/traps.c:950:5: error: no previous prototype for 'is_valid_bugaddr' [-Werror=missing-prototypes] Add an #ifdef that matches the one around the declaration. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20230516160642.523862-10-arnd@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-04-14arm64/cpu: Mark cpu_park_loop() and friends __noreturnJosh Poimboeuf
In preparation for marking panic_smp_self_stop() __noreturn across the kernel, first mark the arm64 implementation of cpu_park_loop() and related functions __noreturn. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/55787d3193ea3e295ccbb097abfab0a10ae49d45.1681342859.git.jpoimboe@kernel.org
2023-03-02Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Catalin Marinas: - In copy_highpage(), only reset the tag of the destination pointer if KASAN_HW_TAGS is enabled so that user-space MTE does not interfere with KASAN_SW_TAGS (which relies on top-byte-ignore). - Remove warning if SME is detected without SVE, the kernel can cope with such configuration (though none in the field currently). - In cfi_handler(), pass the ESR_EL1 value to die() for consistency with other die() callers. - Disable HUGETLB_PAGE_OPTIMIZE_VMEMMAP on arm64 since the pte manipulation from the generic vmemmap_remap_pte() does not follow the required ARM break-before-make sequence (clear the pte, flush the TLBs, set the new pte). It may be re-enabled once this sequence is sorted. - Fix possible memory leak in the arm64 ACPI code if the SMCCC version and conduit checks fail. - Forbid CALL_OPS with CC_OPTIMIZE_FOR_SIZE since gcc ignores -falign-functions=N with -Os. - Don't pretend KASLR is enabled if offset < MIN_KIMG_ALIGN as no randomisation would actually take place. * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: kaslr: don't pretend KASLR is enabled if offset < MIN_KIMG_ALIGN arm64: ftrace: forbid CALL_OPS with CC_OPTIMIZE_FOR_SIZE arm64: acpi: Fix possible memory leak of ffh_ctxt arm64: mm: hugetlb: Disable HUGETLB_PAGE_OPTIMIZE_VMEMMAP arm64: pass ESR_ELx to die() of cfi_handler arm64/fpsimd: Remove warning for SME without SVE arm64: Reset KASAN tag in copy_highpage with HW tags only
2023-02-23Merge tag 'efi-next-for-v6.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI updates from Ard Biesheuvel: "A healthy mix of EFI contributions this time: - Performance tweaks for efifb earlycon (Andy) - Preparatory refactoring and cleanup work in the efivar layer, which is needed to accommodate the Snapdragon arm64 laptops that expose their EFI variable store via a TEE secure world API (Johan) - Enhancements to the EFI memory map handling so that Xen dom0 can safely access EFI configuration tables (Demi Marie) - Wire up the newly introduced IBT/BTI flag in the EFI memory attributes table, so that firmware that is generated with ENDBR/BTI landing pads will be mapped with enforcement enabled - Clean up how we check and print the EFI revision exposed by the firmware - Incorporate EFI memory attributes protocol definition and wire it up in the EFI zboot code (Evgeniy) This ensures that these images can execute under new and stricter rules regarding the default memory permissions for EFI page allocations (More work is in progress here) - CPER header cleanup (Dan Williams) - Use a raw spinlock to protect the EFI runtime services stack on arm64 to ensure the correct semantics under -rt (Pierre) - EFI framebuffer quirk for Lenovo Ideapad (Darrell)" * tag 'efi-next-for-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: (24 commits) firmware/efi sysfb_efi: Add quirk for Lenovo IdeaPad Duet 3 arm64: efi: Make efi_rt_lock a raw_spinlock efi: Add mixed-mode thunk recipe for GetMemoryAttributes efi: x86: Wire up IBT annotation in memory attributes table efi: arm64: Wire up BTI annotation in memory attributes table efi: Discover BTI support in runtime services regions efi/cper, cxl: Remove cxl_err.h efi: Use standard format for printing the EFI revision efi: Drop minimum EFI version check at boot efi: zboot: Use EFI protocol to remap code/data with the right attributes efi/libstub: Add memory attribute protocol definitions efi: efivars: prevent double registration efi: verify that variable services are supported efivarfs: always register filesystem efi: efivars: add efivars printk prefix efi: Warn if trying to reserve memory under Xen efi: Actually enable the ESRT under Xen efi: Apply allowlist to EFI configuration tables when running under Xen efi: xen: Implement memory descriptor lookup based on hypercall efi: memmap: Disregard bogus entries instead of returning them ...
2023-02-22arm64: pass ESR_ELx to die() of cfi_handlerSangmoon Kim
Commit 0f2cb928a154 ("arm64: consistently pass ESR_ELx to die()") caused all callers to pass the ESR_ELx value to die(). For consistency, this patch also adds esr to die() call of cfi_handler. Also, when CFI error occurs, die handlers can use ESR_ELx value. Signed-off-by: Sangmoon Kim <sangmoon.kim@samsung.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20230220073441.2753-1-sangmoon.kim@samsung.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-21Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - Support for arm64 SME 2 and 2.1. SME2 introduces a new 512-bit architectural register (ZT0, for the look-up table feature) that Linux needs to save/restore - Include TPIDR2 in the signal context and add the corresponding kselftests - Perf updates: Arm SPEv1.2 support, HiSilicon uncore PMU updates, ACPI support to the Marvell DDR and TAD PMU drivers, reset DTM_PMU_CONFIG (ARM CMN) at probe time - Support for DYNAMIC_FTRACE_WITH_CALL_OPS on arm64 - Permit EFI boot with MMU and caches on. Instead of cleaning the entire loaded kernel image to the PoC and disabling the MMU and caches before branching to the kernel bare metal entry point, leave the MMU and caches enabled and rely on EFI's cacheable 1:1 mapping of all of system RAM to populate the initial page tables - Expose the AArch32 (compat) ELF_HWCAP features to user in an arm64 kernel (the arm32 kernel only defines the values) - Harden the arm64 shadow call stack pointer handling: stash the shadow stack pointer in the task struct on interrupt, load it directly from this structure - Signal handling cleanups to remove redundant validation of size information and avoid reading the same data from userspace twice - Refactor the hwcap macros to make use of the automatically generated ID registers. It should make new hwcaps writing less error prone - Further arm64 sysreg conversion and some fixes - arm64 kselftest fixes and improvements - Pointer authentication cleanups: don't sign leaf functions, unify asm-arch manipulation - Pseudo-NMI code generation optimisations - Minor fixes for SME and TPIDR2 handling - Miscellaneous updates: ARCH_FORCE_MAX_ORDER is now selectable, replace strtobool() to kstrtobool() in the cpufeature.c code, apply dynamic shadow call stack in two passes, intercept pfn changes in set_pte_at() without the required break-before-make sequence, attempt to dump all instructions on unhandled kernel faults * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (130 commits) arm64: fix .idmap.text assertion for large kernels kselftest/arm64: Don't require FA64 for streaming SVE+ZA tests kselftest/arm64: Copy whole EXTRA context arm64: kprobes: Drop ID map text from kprobes blacklist perf: arm_spe: Print the version of SPE detected perf: arm_spe: Add support for SPEv1.2 inverted event filtering perf: Add perf_event_attr::config3 arm64/sme: Fix __finalise_el2 SMEver check drivers/perf: fsl_imx8_ddr_perf: Remove set-but-not-used variable arm64/signal: Only read new data when parsing the ZT context arm64/signal: Only read new data when parsing the ZA context arm64/signal: Only read new data when parsing the SVE context arm64/signal: Avoid rereading context frame sizes arm64/signal: Make interface for restore_fpsimd_context() consistent arm64/signal: Remove redundant size validation from parse_user_sigframe() arm64/signal: Don't redundantly verify FPSIMD magic arm64/cpufeature: Use helper macros to specify hwcaps arm64/cpufeature: Always use symbolic name for feature value in hwcaps arm64/sysreg: Initial unsigned annotations for ID registers arm64/sysreg: Initial annotation of signed ID registers ...
2023-02-09efi: arm64: Wire up BTI annotation in memory attributes tableArd Biesheuvel
UEFI v2.10 extends the EFI memory attributes table with a flag that indicates whether or not all RuntimeServicesCode regions were constructed with BTI landing pads, permitting the OS to map these regions with BTI restrictions enabled. So let's take this into account on arm64. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Will Deacon <will@kernel.org>
2023-02-08arm64: Support Clang UBSAN trap codes for better reportingKees Cook
When building with CONFIG_UBSAN_TRAP=y on arm64, Clang encodes the UBSAN check (handler) type in the esr. Extract this and actually report these traps as coming from the specific UBSAN check that tripped. Before: Internal error: BRK handler: 00000000f20003e8 [#1] PREEMPT SMP After: Internal error: UBSAN: shift out of bounds: 00000000f2005514 [#1] PREEMPT SMP Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Mukesh Ojha <quic_mojha@quicinc.com> Reviewed-by: Fangrui Song <maskray@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: John Stultz <jstultz@google.com> Cc: Yongqin Liu <yongqin.liu@linaro.org> Cc: Sami Tolvanen <samitolvanen@google.com> Cc: Yury Norov <yury.norov@gmail.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Marco Elver <elver@google.com> Cc: linux-arm-kernel@lists.infradead.org Cc: llvm@lists.linux.dev Signed-off-by: Kees Cook <keescook@chromium.org>
2023-01-27arm64: traps: attempt to dump all instructionsMark Rutland
Currently dump_kernel_instr() dumps a few instructions around the pt_regs::pc value, dumping 4 instructions before the PC before dumping the instruction at the PC. If an attempt to read an instruction fails, it gives up and does not attempt to dump any subsequent instructions. This is unfortunate when the pt_regs::pc value points to the start of a page with a leading guard page, where the instruction at the PC can be read, but prior instructions cannot. This patch makes dump_kernel_instr() attempt to dump each instruction regardless of whether reading a prior instruction could be read, which gives a more useful code dump in such cases. When an instruction cannot be read, it is reported as "????????", which cannot be confused with a hex value, For example, with a `UDF #0` (AKA 0x00000000) early in the kexec control page, we'll now get the following code dump: | Internal error: Oops - Undefined instruction: 0000000002000000 [#1] SMP | Modules linked in: | CPU: 0 PID: 261 Comm: kexec Not tainted 6.2.0-rc5+ #26 | Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 | pstate: 604003c5 (nZCv DAIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : 0x48c00000 | lr : machine_kexec+0x190/0x200 | sp : ffff80000d36ba80 | x29: ffff80000d36ba80 x28: ffff000002dfc380 x27: 0000000000000000 | x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 | x23: ffff80000a9f7858 x22: 000000004c460000 x21: 0000000000000010 | x20: 00000000ad821000 x19: ffff000000aa0000 x18: 0000000000000006 | x17: ffff8000758a2000 x16: ffff800008000000 x15: ffff80000d36b568 | x14: 0000000000000000 x13: ffff80000d36b707 x12: ffff80000a9bf6e0 | x11: 00000000ffffdfff x10: ffff80000aaaf8e0 x9 : ffff80000815eff8 | x8 : 000000000002ffe8 x7 : c0000000ffffdfff x6 : 00000000000affa8 | x5 : 0000000000001fff x4 : 0000000000000001 x3 : ffff80000a263008 | x2 : ffff80000a9e20f8 x1 : 0000000048c00000 x0 : ffff000000aa0000 | Call trace: | 0x48c00000 | kernel_kexec+0x88/0x138 | __do_sys_reboot+0x108/0x288 | __arm64_sys_reboot+0x2c/0x40 | invoke_syscall+0x78/0x140 | el0_svc_common.constprop.0+0x4c/0x100 | do_el0_svc+0x34/0x80 | el0_svc+0x34/0x140 | el0t_64_sync_handler+0xf4/0x140 | el0t_64_sync+0x194/0x1c0 | Code: ???????? ???????? ???????? ???????? (00000000) | ---[ end trace 0000000000000000 ]--- | Kernel panic - not syncing: Oops - Undefined instruction: Fatal exception | Kernel Offset: disabled | CPU features: 0x002000,00050108,c8004203 | Memory Limit: none Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20230127121256.2141368-1-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-11-15arm64: armv8_deprecated: rework deprected instruction handlingMark Rutland
Support for deprecated instructions can be enabled or disabled at runtime. To handle this, the code in armv8_deprecated.c registers and unregisters undef_hooks, and makes cross CPU calls to configure HW support. This is rather complicated, and the synchronization required to make this safe ends up serializing the handling of instructions which have been trapped. This patch simplifies the deprecated instruction handling by removing the dynamic registration and unregistration, and changing the trap handling code to determine whether a handler should be invoked. This removes the need for dynamic list management, and simplifies the locking requirements, making it possible to handle trapped instructions entirely in parallel. Where changing the emulation state requires a cross-call, this is serialized by locally disabling interrupts, ensuring that the CPU is not left in an inconsistent state. To simplify sysctl management, each insn_emulation is given a separate sysctl table, permitting these to be registered separately. The core sysctl code will iterate over all of these when walking sysfs. I've tested this with userspace programs which use each of the deprecated instructions, and I've concurrently modified the support level for each of the features back-and-forth between HW and emulated to check that there are no spurious SIGILLs sent to userspace when the support level is changed. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20221019144123.612388-10-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-15arm64: rework EL0 MRS emulationMark Rutland
On CPUs without FEAT_IDST, ID register emulation is slower than it needs to be, as all threads contend for the same lock to perform the emulation. This patch reworks the emulation to avoid this unnecessary contention. On CPUs with FEAT_IDST (which is mandatory from ARMv8.4 onwards), EL0 accesses to ID registers result in a SYS trap, and emulation of these is handled with a sys64_hook. These hooks are statically allocated, and no locking is required to iterate through the hooks and perform the emulation, allowing emulation to occur in parallel with no contention. On CPUs without FEAT_IDST, EL0 accesses to ID registers result in an UNDEFINED exception, and emulation of these accesses is handled with an undef_hook. When an EL0 MRS instruction is trapped to EL1, the kernel finds the relevant handler by iterating through all of the undef_hooks, requiring undef_lock to be held during this lookup. This locking is only required to safely traverse the list of undef_hooks (as it can be concurrently modified), and the actual emulation of the MRS does not require any mutual exclusion. This locking is an unfortunate bottleneck, especially given that MRS emulation is enabled unconditionally and is never disabled. This patch reworks the non-FEAT_IDST MRS emulation logic so that it can be invoked directly from do_el0_undef(). This removes the bottleneck, allowing MRS traps to be handled entirely in parallel, and is a stepping stone to making all of the undef_hooks lock-free. I've tested this in a 64-vCPU VM on a 64-CPU ThunderX2 host, with a benchmark which spawns a number of threads which each try to read ID_AA64ISAR0_EL1 1000000 times. This is vastly more contention than will ever be seen in realistic usage, but clearly demonstrates the removal of the bottleneck: | Threads || Time (seconds) | | || Before || After | | || Real | System || Real | System | |---------++--------+---------++--------+---------| | 1 || 0.29 | 0.20 || 0.24 | 0.12 | | 2 || 0.35 | 0.51 || 0.23 | 0.27 | | 4 || 1.08 | 3.87 || 0.24 | 0.56 | | 8 || 4.31 | 33.60 || 0.24 | 1.11 | | 16 || 9.47 | 149.39 || 0.23 | 2.15 | | 32 || 19.07 | 605.27 || 0.24 | 4.38 | | 64 || 65.40 | 3609.09 || 0.33 | 11.27 | Aside from the speedup, there should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20221019144123.612388-6-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-15arm64: factor insn read out of call_undef_hook()Mark Rutland
Subsequent patches will rework EL0 UNDEF handling, removing the need for struct undef_hook and call_undef_hook. In preparation for those changes, this patch factors the logic for reading user instructions out of call_undef_hook() and into a new user_insn_read() helper, matching the style of the existing aarch64_insn_read() helper used for reading kernel instructions. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20221019144123.612388-5-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-15arm64: factor out EL1 SSBS emulation hookMark Rutland
Currently call_undef_hook() is used to handle UNDEFINED exceptions from EL0 and EL1. As support for deprecated instructions may be enabled independently, the handlers for individual instructions are organised as a linked list of struct undef_hook which can be manipulated dynamically. As this can be manipulated dynamically, the list is protected with a raw_spinlock which must be acquired when handling UNDEFINED exceptions or when manipulating the list of handlers. This locking is unfortunate as it serialises handling of UNDEFINED exceptions, and requires RCU to be enabled for lockdep, requiring the use of RCU_NONIDLE() in resume path of cpu_suspend() since commit: a2c42bbabbe260b7 ("arm64: spectre: Prevent lockdep splat on v4 mitigation enable path") The list of UNDEFINED handlers largely consist of handlers for exceptions taken from EL0, and the only handler for exceptions taken from EL1 handles `MSR SSBS, #imm` on CPUs which feature PSTATE.SSBS but lack the corresponding MSR (Immediate) instruction. Other than this we never expect to take an UNDEFINED exception from EL1 in normal operation. This patch reworks do_el0_undef() to invoke the EL1 SSBS handler directly, relegating call_undef_hook() to only handle EL0 UNDEFs. This removes redundant work to iterate the list for EL1 UNDEFs, and removes the need for locking, permitting EL1 UNDEFs to be handled in parallel without contention. The RCU_NONIDLE() call in cpu_suspend() will be removed in a subsequent patch, as there are other potential issues with the use of instrumentable code and RCU in the CPU suspend code. I've tested this by forcing the detection of SSBS on a CPU that doesn't have it, and verifying that the try_emulate_el1_ssbs() callback is invoked. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20221019144123.612388-4-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-15arm64: split EL0/EL1 UNDEF handlersMark Rutland
In general, exceptions taken from EL1 need to be handled separately from exceptions taken from EL0, as the logic to handle the two cases can be significantly divergent, and exceptions taken from EL1 typically have more stringent requirements on locking and instrumentation. Subsequent patches will rework the way EL1 UNDEFs are handled in order to address longstanding soundness issues with instrumentation and RCU. In preparation for that rework, this patch splits the existing do_undefinstr() handler into separate do_el0_undef() and do_el1_undef() handlers. Prior to this patch, do_undefinstr() was marked with NOKPROBE_SYMBOL(), preventing instrumentation via kprobes. However, do_undefinstr() invokes other code which can be instrumented, and: * For UNDEFINED exceptions taken from EL0, there is no risk of recursion within kprobes. Therefore it is safe for do_el0_undef to be instrumented with kprobes, and it does not need to be marked with NOKPROBE_SYMBOL(). * For UNDEFINED exceptions taken from EL1, either: (a) The exception is has been taken when manipulating SSBS; these cases are limited and do not occur within code that can be invoked recursively via kprobes. Hence, in these cases instrumentation with kprobes is benign. (b) The exception has been taken for an unknown reason, as other than manipulating SSBS we do not expect to take UNDEFINED exceptions from EL1. Any handling of these exception is best-effort. ... and in either case, marking do_el1_undef() with NOKPROBE_SYMBOL() isn't sufficient to prevent recursion via kprobes as functions it calls (including die()) are instrumentable via kprobes. Hence, it's not worthwhile to mark do_el1_undef() with NOKPROBE_SYMBOL(). The same applies to do_el1_bti() and do_el1_fpac(), so their NOKPROBE_SYMBOL() annotations are also removed. Aside from the new instrumentability, there should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20221019144123.612388-3-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-11-15arm64: allow kprobes on EL0 handlersMark Rutland
Currently do_sysinstr() and do_cp15instr() are marked with NOKPROBE_SYMBOL(). However, these are only called for exceptions taken from EL0, and there is no risk of recursion in kprobes, so this is not necessary. Remove the NOKPROBE_SYMBOL() annotation, and rename the two functions to more clearly indicate that these are solely for exceptions taken from EL0, better matching the names used by the lower level entry points in entry-common.c. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20221019144123.612388-2-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-10-06Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - arm64 perf: DDR PMU driver for Alibaba's T-Head Yitian 710 SoC, SVE vector granule register added to the user regs together with SVE perf extensions documentation. - SVE updates: add HWCAP for SVE EBF16, update the SVE ABI documentation to match the actual kernel behaviour (zeroing the registers on syscall rather than "zeroed or preserved" previously). - More conversions to automatic system registers generation. - vDSO: use self-synchronising virtual counter access in gettimeofday() if the architecture supports it. - arm64 stacktrace cleanups and improvements. - arm64 atomics improvements: always inline assembly, remove LL/SC trampolines. - Improve the reporting of EL1 exceptions: rework BTI and FPAC exception handling, better EL1 undefs reporting. - Cortex-A510 erratum 2658417: remove BF16 support due to incorrect result. - arm64 defconfig updates: build CoreSight as a module, enable options necessary for docker, memory hotplug/hotremove, enable all PMUs provided by Arm. - arm64 ptrace() support for TPIDR2_EL0 (register provided with the SME extensions). - arm64 ftraces updates/fixes: fix module PLTs with mcount, remove unused function. - kselftest updates for arm64: simple HWCAP validation, FP stress test improvements, validation of ZA regs in signal handlers, include larger SVE and SME vector lengths in signal tests, various cleanups. - arm64 alternatives (code patching) improvements to robustness and consistency: replace cpucap static branches with equivalent alternatives, associate callback alternatives with a cpucap. - Miscellaneous updates: optimise kprobe performance of patching single-step slots, simplify uaccess_mask_ptr(), move MTE registers initialisation to C, support huge vmalloc() mappings, run softirqs on the per-CPU IRQ stack, compat (arm32) misalignment fixups for multiword accesses. * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (126 commits) arm64: alternatives: Use vdso/bits.h instead of linux/bits.h arm64/kprobe: Optimize the performance of patching single-step slot arm64: defconfig: Add Coresight as module kselftest/arm64: Handle EINTR while reading data from children kselftest/arm64: Flag fp-stress as exiting when we begin finishing up kselftest/arm64: Don't repeat termination handler for fp-stress ARM64: reloc_test: add __init/__exit annotations to module init/exit funcs arm64/mm: fold check for KFENCE into can_set_direct_map() arm64: ftrace: fix module PLTs with mcount arm64: module: Remove unused plt_entry_is_initialized() arm64: module: Make plt_equals_entry() static arm64: fix the build with binutils 2.27 kselftest/arm64: Don't enable v8.5 for MTE selftest builds arm64: uaccess: simplify uaccess_mask_ptr() arm64: asm/perf_regs.h: Avoid C++-style comment in UAPI header kselftest/arm64: Fix typo in hwcap check arm64: mte: move register initialization to C arm64: mm: handle ARM64_KERNEL_USES_PMD_MAPS in vmemmap_populate() arm64: dma: Drop cache invalidation from arch_dma_prep_coherent() arm64/sve: Add Perf extensions documentation ...
2022-09-26arm64: Add CFI error handlingSami Tolvanen
With -fsanitize=kcfi, CFI always traps. Add arm64 support for handling CFI failures. The registers containing the target address and the expected type are encoded in the first ten bits of the ESR as follows: - 0-4: n, where the register Xn contains the target address - 5-9: m, where the register Wm contains the type hash This produces the following oops on CFI failure (generated using lkdtm): [ 21.885179] CFI failure at lkdtm_indirect_call+0x2c/0x44 [lkdtm] (target: lkdtm_increment_int+0x0/0x1c [lkdtm]; expected type: 0x7e0c52a) [ 21.886593] Internal error: Oops - CFI: 0 [#1] PREEMPT SMP [ 21.891060] Modules linked in: lkdtm [ 21.893363] CPU: 0 PID: 151 Comm: sh Not tainted 5.19.0-rc1-00021-g852f4e48dbab #1 [ 21.895560] Hardware name: linux,dummy-virt (DT) [ 21.896543] pstate: 80400009 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 21.897583] pc : lkdtm_indirect_call+0x2c/0x44 [lkdtm] [ 21.898551] lr : lkdtm_CFI_FORWARD_PROTO+0x3c/0x6c [lkdtm] [ 21.899520] sp : ffff8000083a3c50 [ 21.900191] x29: ffff8000083a3c50 x28: ffff0000027e0ec0 x27: 0000000000000000 [ 21.902453] x26: 0000000000000000 x25: ffffc2aa3d07e7b0 x24: 0000000000000002 [ 21.903736] x23: ffffc2aa3d079088 x22: ffffc2aa3d07e7b0 x21: ffff000003379000 [ 21.905062] x20: ffff8000083a3dc0 x19: 0000000000000012 x18: 0000000000000000 [ 21.906371] x17: 000000007e0c52a5 x16: 000000003ad55aca x15: ffffc2aa60d92138 [ 21.907662] x14: ffffffffffffffff x13: 2e2e2e2065707974 x12: 0000000000000018 [ 21.909775] x11: ffffc2aa62322b88 x10: ffffc2aa62322aa0 x9 : c7e305fb5195d200 [ 21.911898] x8 : ffffc2aa3d077e20 x7 : 6d20676e696c6c61 x6 : 43203a6d74646b6c [ 21.913108] x5 : ffffc2aa6266c9df x4 : ffffc2aa6266c9e1 x3 : ffff8000083a3968 [ 21.914358] x2 : 80000000fffff122 x1 : 00000000fffff122 x0 : ffffc2aa3d07e8f8 [ 21.915827] Call trace: [ 21.916375] lkdtm_indirect_call+0x2c/0x44 [lkdtm] [ 21.918060] lkdtm_CFI_FORWARD_PROTO+0x3c/0x6c [lkdtm] [ 21.919030] lkdtm_do_action+0x34/0x4c [lkdtm] [ 21.919920] direct_entry+0x170/0x1ac [lkdtm] [ 21.920772] full_proxy_write+0x84/0x104 [ 21.921759] vfs_write+0x188/0x3d8 [ 21.922387] ksys_write+0x78/0xe8 [ 21.922986] __arm64_sys_write+0x1c/0x2c [ 21.923696] invoke_syscall+0x58/0x134 [ 21.924554] el0_svc_common+0xb4/0xf4 [ 21.925603] do_el0_svc+0x2c/0xb4 [ 21.926563] el0_svc+0x2c/0x7c [ 21.927147] el0t_64_sync_handler+0x84/0xf0 [ 21.927985] el0t_64_sync+0x18c/0x190 [ 21.929133] Code: 728a54b1 72afc191 6b11021f 54000040 (d4304500) [ 21.930690] ---[ end trace 0000000000000000 ]--- [ 21.930971] Kernel panic - not syncing: Oops - CFI: Fatal exception Suggested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Kees Cook <keescook@chromium.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220908215504.3686827-11-samitolvanen@google.com
2022-09-16arm64: rework BTI exception handlingMark Rutland
If a BTI exception is taken from EL1, the entry code will treat this as an unhandled exception and will panic() the kernel. This is inconsistent with the way we handle FPAC exceptions, which have a dedicated handler and only necessarily kill the thread from which the exception was taken from, and we don't log all the information that could be relevant to debug the issue. The code in do_bti() has: BUG_ON(!user_mode(regs)); ... and it seems like the intent was to call this for EL1 BTI exceptions, as with FPAC, but this was omitted due to an oversight. This patch adds separate EL0 and EL1 BTI exception handlers, with the latter calling die() directly to report the original context the BTI exception was taken from. This matches our handling of FPAC exceptions. Prior to this patch, a BTI failure is reported as: | Unhandled 64-bit el1h sync exception on CPU0, ESR 0x0000000034000002 -- BTI | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.19.0-rc3-00131-g7d937ff0221d-dirty #9 | Hardware name: linux,dummy-virt (DT) | pstate: 20400809 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=-c) | pc : test_bti_callee+0x4/0x10 | lr : test_bti_caller+0x1c/0x28 | sp : ffff80000800bdf0 | x29: ffff80000800bdf0 x28: 0000000000000000 x27: 0000000000000000 | x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 | x23: ffff80000a2b8000 x22: 0000000000000000 x21: 0000000000000000 | x20: ffff8000099fa5b0 x19: ffff800009ff7000 x18: fffffbfffda37000 | x17: 3120676e696d7573 x16: 7361202c6e6f6974 x15: 0000000041a90000 | x14: 0040000000000041 x13: 0040000000000001 x12: ffff000001a90000 | x11: fffffbfffda37480 x10: 0068000000000703 x9 : 0001000040000000 | x8 : 0000000000090000 x7 : 0068000000000f03 x6 : 0060000000000f83 | x5 : ffff80000a2b6000 x4 : ffff0000028d0000 x3 : ffff800009f78378 | x2 : 0000000000000000 x1 : 0000000040210000 x0 : ffff8000080257e4 | Kernel panic - not syncing: Unhandled exception | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.19.0-rc3-00131-g7d937ff0221d-dirty #9 | Hardware name: linux,dummy-virt (DT) | Call trace: | dump_backtrace.part.0+0xcc/0xe0 | show_stack+0x18/0x5c | dump_stack_lvl+0x64/0x80 | dump_stack+0x18/0x34 | panic+0x170/0x360 | arm64_exit_nmi.isra.0+0x0/0x80 | el1h_64_sync_handler+0x64/0xd0 | el1h_64_sync+0x64/0x68 | test_bti_callee+0x4/0x10 | smp_cpus_done+0xb0/0xbc | smp_init+0x7c/0x8c | kernel_init_freeable+0x128/0x28c | kernel_init+0x28/0x13c | ret_from_fork+0x10/0x20 With this patch applied, a BTI failure is reported as: | Internal error: Oops - BTI: 0000000034000002 [#1] PREEMPT SMP | Modules linked in: | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.19.0-rc3-00132-g0ad98265d582-dirty #8 | Hardware name: linux,dummy-virt (DT) | pstate: 20400809 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=-c) | pc : test_bti_callee+0x4/0x10 | lr : test_bti_caller+0x1c/0x28 | sp : ffff80000800bdf0 | x29: ffff80000800bdf0 x28: 0000000000000000 x27: 0000000000000000 | x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 | x23: ffff80000a2b8000 x22: 0000000000000000 x21: 0000000000000000 | x20: ffff8000099fa5b0 x19: ffff800009ff7000 x18: fffffbfffda37000 | x17: 3120676e696d7573 x16: 7361202c6e6f6974 x15: 0000000041a90000 | x14: 0040000000000041 x13: 0040000000000001 x12: ffff000001a90000 | x11: fffffbfffda37480 x10: 0068000000000703 x9 : 0001000040000000 | x8 : 0000000000090000 x7 : 0068000000000f03 x6 : 0060000000000f83 | x5 : ffff80000a2b6000 x4 : ffff0000028d0000 x3 : ffff800009f78378 | x2 : 0000000000000000 x1 : 0000000040210000 x0 : ffff800008025804 | Call trace: | test_bti_callee+0x4/0x10 | smp_cpus_done+0xb0/0xbc | smp_init+0x7c/0x8c | kernel_init_freeable+0x128/0x28c | kernel_init+0x28/0x13c | ret_from_fork+0x10/0x20 | Code: d50323bf d53cd040 d65f03c0 d503233f (d50323bf) Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Amit Daniel Kachhap <amit.kachhap@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20220913101732.3925290-6-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-16arm64: rework FPAC exception handlingMark Rutland
If an FPAC exception is taken from EL1, the entry code will call do_ptrauth_fault(), where due to: BUG_ON(!user_mode(regs)) ... the kernel will report a problem within do_ptrauth_fault() rather than reporting the original context the FPAC exception was taken from. The pt_regs and ESR value reported will be from within do_ptrauth_fault() and the code dump will be for the BRK in BUG_ON(), which isn't sufficient to debug the cause of the original exception. This patch makes the reporting better by having separate EL0 and EL1 FPAC exception handlers, with the latter calling die() directly to report the original context the FPAC exception was taken from. Note that we only need to prevent kprobes of the EL1 FPAC handler, since the EL0 FPAC handler cannot be called recursively. For consistency with do_el0_svc*(), I've named the split functions do_el{0,1}_fpac() rather than do_el{0,1}_ptrauth_fault(). I've also clarified the comment to not imply there are casues other than FPAC exceptions. Prior to this patch FPAC exceptions are reported as: | kernel BUG at arch/arm64/kernel/traps.c:517! | Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP | Modules linked in: | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.19.0-rc3-00130-g9c8a180a1cdf-dirty #12 | Hardware name: FVP Base RevC (DT) | pstate: 00400009 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : do_ptrauth_fault+0x3c/0x40 | lr : el1_fpac+0x34/0x54 | sp : ffff80000a3bbc80 | x29: ffff80000a3bbc80 x28: ffff0008001d8000 x27: 0000000000000000 | x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 | x23: 0000000020400009 x22: ffff800008f70fa4 x21: ffff80000a3bbe00 | x20: 0000000072000000 x19: ffff80000a3bbcb0 x18: fffffbfffda37000 | x17: 3120676e696d7573 x16: 7361202c6e6f6974 x15: 0000000081a90000 | x14: 0040000000000041 x13: 0040000000000001 x12: ffff000001a90000 | x11: fffffbfffda37480 x10: 0068000000000703 x9 : 0001000080000000 | x8 : 0000000000090000 x7 : 0068000000000f03 x6 : 0060000000000783 | x5 : ffff80000a3bbcb0 x4 : ffff0008001d8000 x3 : 0000000072000000 | x2 : 0000000000000000 x1 : 0000000020400009 x0 : ffff80000a3bbcb0 | Call trace: | do_ptrauth_fault+0x3c/0x40 | el1h_64_sync_handler+0xc4/0xd0 | el1h_64_sync+0x64/0x68 | test_pac+0x8/0x10 | smp_init+0x7c/0x8c | kernel_init_freeable+0x128/0x28c | kernel_init+0x28/0x13c | ret_from_fork+0x10/0x20 | Code: 97fffe5e a8c17bfd d50323bf d65f03c0 (d4210000) With this patch applied FPAC exceptions are reported as: | Internal error: Oops - FPAC: 0000000072000000 [#1] PREEMPT SMP | Modules linked in: | CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.19.0-rc3-00132-g78846e1c4757-dirty #11 | Hardware name: FVP Base RevC (DT) | pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : test_pac+0x8/0x10 | lr : 0x0 | sp : ffff80000a3bbe00 | x29: ffff80000a3bbe00 x28: 0000000000000000 x27: 0000000000000000 | x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 | x23: ffff80000a2c8000 x22: 0000000000000000 x21: 0000000000000000 | x20: ffff8000099fa5b0 x19: ffff80000a007000 x18: fffffbfffda37000 | x17: 3120676e696d7573 x16: 7361202c6e6f6974 x15: 0000000081a90000 | x14: 0040000000000041 x13: 0040000000000001 x12: ffff000001a90000 | x11: fffffbfffda37480 x10: 0068000000000703 x9 : 0001000080000000 | x8 : 0000000000090000 x7 : 0068000000000f03 x6 : 0060000000000783 | x5 : ffff80000a2c6000 x4 : ffff0008001d8000 x3 : ffff800009f88378 | x2 : 0000000000000000 x1 : 0000000080210000 x0 : ffff000001a90000 | Call trace: | test_pac+0x8/0x10 | smp_init+0x7c/0x8c | kernel_init_freeable+0x128/0x28c | kernel_init+0x28/0x13c | ret_from_fork+0x10/0x20 | Code: d50323bf d65f03c0 d503233f aa1f03fe (d50323bf) Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Amit Daniel Kachhap <amit.kachhap@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20220913101732.3925290-5-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-16arm64: consistently pass ESR_ELx to die()Mark Rutland
Currently, bug_handler() and kasan_handler() call die() with '0' as the 'err' value, whereas die_kernel_fault() passes the ESR_ELx value. For consistency, this patch ensures we always pass the ESR_ELx value to die(). As this is only called for exceptions taken from kernel mode, there should be no user-visible change as a result of this patch. For UNDEFINED exceptions, I've had to modify do_undefinstr() and its callers to pass the ESR_ELx value. In all cases the ESR_ELx value had already been read and was available. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Mark Brown <broonie@kernel.org> Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Amit Daniel Kachhap <amit.kachhap@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20220913101732.3925290-4-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-16arm64: die(): pass 'err' as longMark Rutland
Recently, we reworked a lot of code to consistentlt pass ESR_ELx as a 64-bit quantity. However, we missed that this can be passed into die() and __die() as the 'err' parameter where it is truncated to a 32-bit int. As notify_die() already takes 'err' as a long, this patch changes die() and __die() to also take 'err' as a long, ensuring that the full value of ESR_ELx is retained. At the same time, die() is updated to consistently log 'err' as a zero-padded 64-bit quantity. Subsequent patches will pass the ESR_ELx value to die() for a number of exceptions. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Amit Daniel Kachhap <amit.kachhap@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20220913101732.3925290-3-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-16arm64: report EL1 UNDEFs betterMark Rutland
If an UNDEFINED exception is taken from EL1, and do_undefinstr() doesn't find any suitable undef_hook, it will call: BUG_ON(!user_mode(regs)) ... and the kernel will report a failure witin do_undefinstr() rather than reporting the original context that the UNDEFINED exception was taken from. The pt_regs and ESR value reported within the BUG() handler will be from within do_undefinstr() and the code dump will be for the BRK in BUG_ON(), which isn't sufficient to debug the cause of the original exception. This patch makes the reporting better by having do_undefinstr() call die() directly in this case to report the original context from which the UNDEFINED exception was taken. Prior to this patch, an undefined instruction is reported as: | kernel BUG at arch/arm64/kernel/traps.c:497! | Internal error: Oops - BUG: 0 [#1] PREEMPT SMP | Modules linked in: | CPU: 0 PID: 0 Comm: swapper Not tainted 5.19.0-rc3-00127-geff044f1b04e-dirty #3 | Hardware name: linux,dummy-virt (DT) | pstate: 000000c5 (nzcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : do_undefinstr+0x28c/0x2ac | lr : do_undefinstr+0x298/0x2ac | sp : ffff800009f63bc0 | x29: ffff800009f63bc0 x28: ffff800009f73c00 x27: ffff800009644a70 | x26: ffff8000096778a8 x25: 0000000000000040 x24: 0000000000000000 | x23: 00000000800000c5 x22: ffff800009894060 x21: ffff800009f63d90 | x20: 0000000000000000 x19: ffff800009f63c40 x18: 0000000000000006 | x17: 0000000000403000 x16: 00000000bfbfd000 x15: ffff800009f63830 | x14: ffffffffffffffff x13: 0000000000000000 x12: 0000000000000019 | x11: 0101010101010101 x10: 0000000000161b98 x9 : 0000000000000000 | x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 | x5 : ffff800009f761d0 x4 : 0000000000000000 x3 : ffff80000a2b80f8 | x2 : 0000000000000000 x1 : ffff800009f73c00 x0 : 00000000800000c5 | Call trace: | do_undefinstr+0x28c/0x2ac | el1_undef+0x2c/0x4c | el1h_64_sync_handler+0x84/0xd0 | el1h_64_sync+0x64/0x68 | setup_arch+0x550/0x598 | start_kernel+0x88/0x6ac | __primary_switched+0xb8/0xc0 | Code: 17ffff95 a9425bf5 17ffffb8 a9025bf5 (d4210000) With this patch applied, an undefined instruction is reported as: | Internal error: Oops - Undefined instruction: 0 [#1] PREEMPT SMP | Modules linked in: | CPU: 0 PID: 0 Comm: swapper Not tainted 5.19.0-rc3-00128-gf27cfcc80e52-dirty #5 | Hardware name: linux,dummy-virt (DT) | pstate: 800000c5 (Nzcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : setup_arch+0x550/0x598 | lr : setup_arch+0x50c/0x598 | sp : ffff800009f63d90 | x29: ffff800009f63d90 x28: 0000000081000200 x27: ffff800009644a70 | x26: ffff8000096778c8 x25: 0000000000000040 x24: 0000000000000000 | x23: 0000000000000100 x22: ffff800009f69a58 x21: ffff80000a2b80b8 | x20: 0000000000000000 x19: 0000000000000000 x18: 0000000000000006 | x17: 0000000000403000 x16: 00000000bfbfd000 x15: ffff800009f63830 | x14: ffffffffffffffff x13: 0000000000000000 x12: 0000000000000019 | x11: 0101010101010101 x10: 0000000000161b98 x9 : 0000000000000000 | x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 | x5 : 0000000000000008 x4 : 0000000000000010 x3 : 0000000000000000 | x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 | Call trace: | setup_arch+0x550/0x598 | start_kernel+0x88/0x6ac | __primary_switched+0xb8/0xc0 | Code: b4000080 90ffed80 912ac000 97db745f (00000000) Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Amit Daniel Kachhap <amit.kachhap@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20220913101732.3925290-2-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-07-05arm64/sysreg: Standardise naming for CTR_EL0 fieldsMark Brown
cache.h contains some defines which are used to represent fields and enumeration values which do not follow the standard naming convention used for when we automatically generate defines for system registers. Update the names of the constants to reflect standardised naming and move them to sysreg.h. There is also a helper CTR_L1IP() which was open coded and has been converted to use SYS_FIELD_GET(). Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20220704170302.2609529-7-broonie@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2022-05-20Merge branch 'for-next/esr-elx-64-bit' into for-next/coreCatalin Marinas
* for-next/esr-elx-64-bit: : Treat ESR_ELx as a 64-bit register. KVM: arm64: uapi: Add kvm_debug_exit_arch.hsr_high KVM: arm64: Treat ESR_EL2 as a 64-bit register arm64: Treat ESR_ELx as a 64-bit register arm64: compat: Do not treat syscall number as ESR_ELx for a bad syscall arm64: Make ESR_ELx_xVC_IMM_MASK compatible with assembly
2022-04-29arm64: Treat ESR_ELx as a 64-bit registerAlexandru Elisei
In the initial release of the ARM Architecture Reference Manual for ARMv8-A, the ESR_ELx registers were defined as 32-bit registers. This changed in 2018 with version D.a (ARM DDI 0487D.a) of the architecture, when they became 64-bit registers, with bits [63:32] defined as RES0. In version G.a, a new field was added to ESR_ELx, ISS2, which covers bits [36:32]. This field is used when the Armv8.7 extension FEAT_LS64 is implemented. As a result of the evolution of the register width, Linux stores it as both a 64-bit value and a 32-bit value, which hasn't affected correctness so far as Linux only uses the lower 32 bits of the register. Make the register type consistent and always treat it as 64-bit wide. The register is redefined as an "unsigned long", which is an unsigned double-word (64-bit quantity) for the LP64 machine (aapcs64 [1], Table 1, page 14). The type was chosen because "unsigned int" is the most frequent type for ESR_ELx and because FAR_ELx, which is used together with ESR_ELx in exception handling, is also declared as "unsigned long". The 64-bit type also makes adding support for architectural features that use fields above bit 31 easier in the future. The KVM hypervisor will receive a similar update in a subsequent patch. [1] https://github.com/ARM-software/abi-aa/releases/download/2021Q3/aapcs64.pdf Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220425114444.368693-4-alexandru.elisei@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-04-22arm64/sme: System register and exception syndrome definitionsMark Brown
The arm64 Scalable Matrix Extension (SME) adds some new system registers, fields in existing system registers and exception syndromes. This patch adds definitions for these for use in future patches implementing support for this extension. Since SME will be the first user of FEAT_HCX in the kernel also include the definitions for enumerating it and the HCRX system register it adds. Signed-off-by: Mark Brown <broonie@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20220419112247.711548-6-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-03-23Merge tag 'asm-generic-5.18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic updates from Arnd Bergmann: "There are three sets of updates for 5.18 in the asm-generic tree: - The set_fs()/get_fs() infrastructure gets removed for good. This was already gone from all major architectures, but now we can finally remove it everywhere, which loses some particularly tricky and error-prone code. There is a small merge conflict against a parisc cleanup, the solution is to use their new version. - The nds32 architecture ends its tenure in the Linux kernel. The hardware is still used and the code is in reasonable shape, but the mainline port is not actively maintained any more, as all remaining users are thought to run vendor kernels that would never be updated to a future release. - A series from Masahiro Yamada cleans up some of the uapi header files to pass the compile-time checks" * tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (27 commits) nds32: Remove the architecture uaccess: remove CONFIG_SET_FS ia64: remove CONFIG_SET_FS support sh: remove CONFIG_SET_FS support sparc64: remove CONFIG_SET_FS support lib/test_lockup: fix kernel pointer check for separate address spaces uaccess: generalize access_ok() uaccess: fix type mismatch warnings from access_ok() arm64: simplify access_ok() m68k: fix access_ok for coldfire MIPS: use simpler access_ok() MIPS: Handle address errors for accesses above CPU max virtual user address uaccess: add generic __{get,put}_kernel_nofault nios2: drop access_ok() check from __put_user() x86: use more conventional access_ok() definition x86: remove __range_not_ok() sparc64: add __{get,put}_kernel_nofault() nds32: fix access_ok() checks in get/put_user uaccess: fix nios2 and microblaze get_user_8() sparc64: fix building assembly files ...
2022-03-08arm64: drop unused includes of <linux/personality.h>Sagar Patel
Drop several includes of <linux/personality.h> which are not used. git-blame indicates they were used at some point, but they're not needed anymore. Signed-off-by: Sagar Patel <sagarmp@cs.unc.edu> Link: https://lore.kernel.org/r/20220307222412.146506-1-sagarmp@cs.unc.edu Signed-off-by: Will Deacon <will@kernel.org>
2022-02-25uaccess: remove CONFIG_SET_FSArnd Bergmann
There are no remaining callers of set_fs(), so CONFIG_SET_FS can be removed globally, along with the thread_info field and any references to it. This turns access_ok() into a cheaper check against TASK_SIZE_MAX. As CONFIG_SET_FS is now gone, drop all remaining references to set_fs()/get_fs(), mm_segment_t, user_addr_max() and uaccess_kernel(). Acked-by: Sam Ravnborg <sam@ravnborg.org> # for sparc32 changes Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Tested-by: Sergey Matyukevich <sergey.matyukevich@synopsys.com> # for arc changes Acked-by: Stafford Horne <shorne@gmail.com> # [openrisc, asm-generic] Acked-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-01-17Merge branch 'signal-for-v5.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull signal/exit/ptrace updates from Eric Biederman: "This set of changes deletes some dead code, makes a lot of cleanups which hopefully make the code easier to follow, and fixes bugs found along the way. The end-game which I have not yet reached yet is for fatal signals that generate coredumps to be short-circuit deliverable from complete_signal, for force_siginfo_to_task not to require changing userspace configured signal delivery state, and for the ptrace stops to always happen in locations where we can guarantee on all architectures that the all of the registers are saved and available on the stack. Removal of profile_task_ext, profile_munmap, and profile_handoff_task are the big successes for dead code removal this round. A bunch of small bug fixes are included, as most of the issues reported were small enough that they would not affect bisection so I simply added the fixes and did not fold the fixes into the changes they were fixing. There was a bug that broke coredumps piped to systemd-coredump. I dropped the change that caused that bug and replaced it entirely with something much more restrained. Unfortunately that required some rebasing. Some successes after this set of changes: There are few enough calls to do_exit to audit in a reasonable amount of time. The lifetime of struct kthread now matches the lifetime of struct task, and the pointer to struct kthread is no longer stored in set_child_tid. The flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is removed. Issues where task->exit_code was examined with signal->group_exit_code should been examined were fixed. There are several loosely related changes included because I am cleaning up and if I don't include them they will probably get lost. The original postings of these changes can be found at: https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org I trimmed back the last set of changes to only the obviously correct once. Simply because there was less time for review than I had hoped" * 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits) ptrace/m68k: Stop open coding ptrace_report_syscall ptrace: Remove unused regs argument from ptrace_report_syscall ptrace: Remove second setting of PT_SEIZED in ptrace_attach taskstats: Cleanup the use of task->exit_code exit: Use the correct exit_code in /proc/<pid>/stat exit: Fix the exit_code for wait_task_zombie exit: Coredumps reach do_group_exit exit: Remove profile_handoff_task exit: Remove profile_task_exit & profile_munmap signal: clean up kernel-doc comments signal: Remove the helper signal_group_exit signal: Rename group_exit_task group_exec_task coredump: Stop setting signal->group_exit_task signal: Remove SIGNAL_GROUP_COREDUMP signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process signal: Make coredump handling explicit in complete_signal signal: Have prepare_signal detect coredumps using signal->core_state signal: Have the oom killer detect coredumps using signal->core_state exit: Move force_uaccess back into do_exit exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit ...
2021-12-13exit: Add and use make_task_dead.Eric W. Biederman
There are two big uses of do_exit. The first is it's design use to be the guts of the exit(2) system call. The second use is to terminate a task after something catastrophic has happened like a NULL pointer in kernel code. Add a function make_task_dead that is initialy exactly the same as do_exit to cover the cases where do_exit is called to handle catastrophic failure. In time this can probably be reduced to just a light wrapper around do_task_dead. For now keep it exactly the same so that there will be no behavioral differences introducing this new concept. Replace all of the uses of do_exit that use it for catastraphic task cleanup with make_task_dead to make it clear what the code is doing. As part of this rename rewind_stack_do_exit rewind_stack_and_make_dead. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-11-08arm64/bpf: Remove 128MB limit for BPF JIT programsRussell King
Commit 91fc957c9b1d ("arm64/bpf: don't allocate BPF JIT programs in module memory") restricts BPF JIT program allocation to a 128MB region to ensure BPF programs are still in branching range of each other. However this restriction should not apply to the aarch64 JIT, since BPF_JMP | BPF_CALL are implemented as a 64-bit move into a register and then a BLR instruction - which has the effect of being able to call anything without proximity limitation. The practical reason to relax this restriction on JIT memory is that 128MB of JIT memory can be quickly exhausted, especially where PAGE_SIZE is 64KB - one page is needed per program. In cases where seccomp filters are applied to multiple VMs on VM launch - such filters are classic BPF but converted to BPF - this can severely limit the number of VMs that can be launched. In a world where we support BPF JIT always on, turning off the JIT isn't always an option either. Fixes: 91fc957c9b1d ("arm64/bpf: don't allocate BPF JIT programs in module memory") Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <russell.king@oracle.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Alan Maguire <alan.maguire@oracle.com> Link: https://lore.kernel.org/bpf/1636131046-5982-2-git-send-email-alan.maguire@oracle.com
2021-10-29Merge branch 'for-next/misc' into for-next/coreWill Deacon
* for-next/misc: arm64: Select POSIX_CPU_TIMERS_TASK_WORK arm64: Document boot requirements for FEAT_SME_FA64 arm64: ftrace: use function_nocfi for _mcount as well arm64: asm: setup.h: export common variables arm64/traps: Avoid unnecessary kernel/user pointer conversion
2021-10-29Merge branch 'for-next/extable' into for-next/coreWill Deacon
* for-next/extable: arm64: vmlinux.lds.S: remove `.fixup` section arm64: extable: add load_unaligned_zeropad() handler arm64: extable: add a dedicated uaccess handler arm64: extable: add `type` and `data` fields arm64: extable: use `ex` for `exception_table_entry` arm64: extable: make fixup_exception() return bool arm64: extable: consolidate definitions arm64: gpr-num: support W registers arm64: factor out GPR numbering helpers arm64: kvm: use kvm_exception_table_entry arm64: lib: __arch_copy_to_user(): fold fixups into body arm64: lib: __arch_copy_from_user(): fold fixups into body arm64: lib: __arch_clear_user(): fold fixups into body
2021-10-21arm64: extable: add a dedicated uaccess handlerMark Rutland
For inline assembly, we place exception fixups out-of-line in the `.fixup` section such that these are out of the way of the fast path. This has a few drawbacks: * Since the fixup code is anonymous, backtraces will symbolize fixups as offsets from the nearest prior symbol, currently `__entry_tramp_text_end`. This is confusing, and painful to debug without access to the relevant vmlinux. * Since the exception handler adjusts the PC to execute the fixup, and the fixup uses a direct branch back into the function it fixes, backtraces of fixups miss the original function. This is confusing, and violates requirements for RELIABLE_STACKTRACE (and therefore LIVEPATCH). * Inline assembly and associated fixups are generated from templates, and we have many copies of logically identical fixups which only differ in which specific registers are written to and which address is branched to at the end of the fixup. This is potentially wasteful of I-cache resources, and makes it hard to add additional logic to fixups without significant bloat. This patch address all three concerns for inline uaccess fixups by adding a dedicated exception handler which updates registers in exception context and subsequent returns back into the function which faulted, removing the need for fixups specialized to each faulting instruction. Other than backtracing, there should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20211019160219.5202-12-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2021-10-19arm64: Add handling of CNTVCTSS trapsMarc Zyngier
Since CNTVCTSS obey the same control bits as CNTVCT, add the necessary decoding to the hook table. Note that there is no known user of this at the moment. Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211017124225.3018098-17-maz@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2021-09-29arm64/traps: Avoid unnecessary kernel/user pointer conversionAmit Daniel Kachhap
Annotating a pointer from kernel to __user and then back again requires an extra __force annotation to silent sparse warning. In call_undef_hook() this unnecessary complexity can be avoided by modifying the intermediate user pointer to unsigned long. This way there is no inter-changeable use of user and kernel pointers and the code is consistent. Note: This patch adds no functional changes to code. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20210917055811.22341-1-amit.kachhap@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2021-06-24Merge branch 'for-next/insn' into for-next/coreWill Deacon
Refactoring of our instruction decoding routines and addition of some missing encodings. * for-next/insn: arm64: insn: avoid circular include dependency arm64: insn: move AARCH64_INSN_SIZE into <asm/insn.h> arm64: insn: decouple patching from insn code arm64: insn: Add load/store decoding helpers arm64: insn: Add some opcodes to instruction decoder arm64: insn: Add barrier encodings arm64: insn: Add SVE instruction class arm64: Move instruction encoder/decoder under lib/ arm64: Move aarch32 condition check functions arm64: Move patching utilities out of instruction encoding/decoding
2021-06-11arm64: insn: move AARCH64_INSN_SIZE into <asm/insn.h>Mark Rutland
For histroical reasons, we define AARCH64_INSN_SIZE in <asm/alternative-macros.h>, but it would make more sense to do so in <asm/insn.h>. Let's move it into <asm/insn.h>, and add the necessary include directives for this. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210609102301.17332-3-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2021-06-11arm64: insn: decouple patching from insn codeMark Rutland
Currently, <asm/insn.h> includes <asm/patching.h>. We intend that <asm/insn.h> will be usable from userspace, so it doesn't make sense to include headers for kernel-only features such as the patching routines, and we'd intended to restrict <asm/insn.h> to instruction encoding details. Let's decouple the patching code from <asm/insn.h>, and explicitly include <asm/patching.h> where it is needed. Since <asm/patching.h> isn't included from assembly, we can drop the __ASSEMBLY__ guards. At the same time, sort the kprobes includes so that it's easier to see what is and isn't incldued. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210609102301.17332-2-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2021-06-07arm64: entry: split bad stack entryMark Rutland
We'd like to keep all the entry sequencing in entry-common.c, as this will allow us to ensure this is consistent, and free from any unsound instrumentation. Currently handle_bad_stack() performs the NMI entry sequence in traps.c. Let's split the low-level entry sequence from the reporting, moving the former to entry-common.c and keeping the latter in traps.c. To make it clear that reporting function never returns, it is renamed to panic_bad_stack(). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Joey Gouly <joey.gouly@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210607094624.34689-17-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2021-06-07arm64: entry: handle all vectors with CMark Rutland
We have 16 architectural exception vectors, and depending on kernel configuration we handle 8 or 12 of these with C code, with the remaining 8 or 4 of these handled as special cases in the entry assembly. It would be nicer if the entry assembly were uniform for all exceptions, and we deferred any specific handling of the exceptions to C code. This way the entry assembly can be more easily templated without ifdeffery or special cases, and it's easier to modify the handling of these cases in future (e.g. to dump additional registers other context). This patch reworks the entry code so that we always have a C handler for every architectural exception vector, with the entry assembly being completely uniform. We now have to handle exceptions from EL1t and EL1h, and also have to handle exceptions from AArch32 even when the kernel is built without CONFIG_COMPAT. To make this clear and to simplify templating, we rename the top-level exception handlers with a consistent naming scheme: asm: <el+sp>_<regsize>_<type> c: <el+sp>_<regsize>_<type>_handler .. where: <el+sp> is `el1t`, `el1h`, or `el0t` <regsize> is `64` or `32` <type> is `sync`, `irq`, `fiq`, or `error` ... e.g. asm: el1h_64_sync c: el1h_64_sync_handler ... with lower-level handlers simply using "el1" and "compat" as today. For unexpected exceptions, this information is passed to __panic_unhandled(), so it can report the specific vector an unexpected exception was taken from, e.g. | Unhandled 64-bit el1t sync exception For vectors we never expect to enter legitimately, the C code is generated using a macro to avoid code duplication. The exceptions are handled via __panic_unhandled(), replacing bad_mode() (which is removed). The `kernel_ventry` and `entry_handler` assembly macros are updated to handle the new naming scheme. In theory it should be possible to generate the entry functions at the same time as the vectors using a single table, but this will require reworking the linker script to split the two into separate sections, so for now we have separate tables. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Joey Gouly <joey.gouly@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210607094624.34689-15-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>