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2023-06-15Merge branch kvm-arm64/misc into kvmarm/nextOliver Upton
* kvm-arm64/misc: : Miscellaneous updates : : - Avoid trapping CTR_EL0 on systems with FEAT_EVT, as the register is : commonly read by userspace : : - Make use of FEAT_BTI at hyp stage-1, setting the Guard Page bit to 1 : for executable mappings : : - Use a separate set of pointer authentication keys for the hypervisor : when running in protected mode (i.e. pKVM) : : - Plug a few holes in timer initialization where KVM fails to free the : timer IRQ(s) KVM: arm64: Use different pointer authentication keys for pKVM KVM: arm64: timers: Fix resource leaks in kvm_timer_hyp_init() KVM: arm64: Use BTI for nvhe KVM: arm64: Relax trapping of CTR_EL0 when FEAT_EVT is available Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-15Merge branch kvm-arm64/configurable-id-regs into kvmarm/nextOliver Upton
* kvm-arm64/configurable-id-regs: : Configurable ID register infrastructure, courtesy of Jing Zhang : : Create generalized infrastructure for allowing userspace to select the : supported feature set for a VM, so long as the feature set is a subset : of what hardware + KVM allows. This does not add any new features that : are user-configurable, and instead focuses on the necessary refactoring : to enable future work. : : As a consequence of the series, feature asymmetry is now deliberately : disallowed for KVM. It is unlikely that VMMs ever configured VMs with : asymmetry, nor does it align with the kernel's overall stance that : features must be uniform across all cores in the system. : : Furthermore, KVM incorrectly advertised an IMP_DEF PMU to guests for : some time. Migrations from affected kernels was supported by explicitly : allowing such an ID register value from userspace, and forwarding that : along to the guest. KVM now allows an IMP_DEF PMU version to be restored : through the ID register interface, but reinterprets the user value as : not implemented (0). KVM: arm64: Rip out the vestiges of the 'old' ID register scheme KVM: arm64: Handle ID register reads using the VM-wide values KVM: arm64: Use generic sanitisation for ID_AA64PFR0_EL1 KVM: arm64: Use generic sanitisation for ID_(AA64)DFR0_EL1 KVM: arm64: Use arm64_ftr_bits to sanitise ID register writes KVM: arm64: Save ID registers' sanitized value per guest KVM: arm64: Reuse fields of sys_reg_desc for idreg KVM: arm64: Rewrite IMPDEF PMU version as NI KVM: arm64: Make vCPU feature flags consistent VM-wide KVM: arm64: Relax invariance of KVM_ARM_VCPU_POWER_OFF KVM: arm64: Separate out feature sanitisation and initialisation Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-15Merge branch for-next/module-alloc into kvmarm/nextOliver Upton
* for-next/module-alloc: : Drag in module VA rework to handle conflicts w/ sw feature refactor 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 Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-15KVM: arm64: Use arm64_ftr_bits to sanitise ID register writesJing Zhang
Rather than reinventing the wheel in KVM to do ID register sanitisation we can rely on the work already done in the core kernel. Implement a generalized sanitisation of ID registers based on the combination of the arm64_ftr_bits definitions from the core kernel and (optionally) a set of KVM-specific overrides. This all amounts to absolutely nothing for now, but will be used in subsequent changes to realize user-configurable ID registers. Signed-off-by: Jing Zhang <jingzhangos@google.com> Link: https://lore.kernel.org/r/20230609190054.1542113-8-oliver.upton@linux.dev [Oliver: split off from monster patch, rewrote commit description, reworked RAZ handling, return EINVAL to userspace] Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-15KVM: arm64: Fix hVHE init on CPUs where HCR_EL2.E2H is not RES1Marc Zyngier
On CPUs where E2H is RES1, we very quickly set the scene for running EL2 with a VHE configuration, as we do not have any other choice. However, CPUs that conform to the current writing of the architecture start with E2H=0, and only later upgrade with E2H=1. This is all good, but nothing there is actually reconfiguring EL2 to be able to correctly run the kernel at EL1. Huhuh... The "obvious" solution is not to just reinitialise the timer controls like we do, but to really intitialise *everything* unconditionally. This requires a bit of surgery, and is a good opportunity to remove the macro that messes with SPSR_EL2 in init_el2_state. With that, hVHE now works correctly on my trusted A55 machine! Reported-by: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230614155129.2697388-1-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-12arm64: Allow arm64_sw.hvhe on command lineMarc Zyngier
Add the arm64_sw.hvhe=1 option to force the use of the hVHE mode in the hypervisor code only. This enables the hVHE mode of operation when using KVM on VHE hardware. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20230609162200.2024064-17-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-12arm64: Don't enable VHE for the kernel if OVERRIDE_HVHE is setMarc Zyngier
If the OVERRIDE_HVHE SW override is set (as a precursor of the KVM_HVHE capability), do not enable VHE for the kernel and drop to EL1 as if VHE was either disabled or unavailable. Further changes will enable VHE at EL2 only, with the kernel still running at EL1. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20230609162200.2024064-6-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-12arm64: Add KVM_HVHE capability and has_hvhe() predicateMarc Zyngier
Expose a capability keying the hVHE feature as well as a new predicate testing it. Nothing is so far using it, and nothing is enabling it yet. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20230609162200.2024064-5-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-12arm64: Turn kaslr_feature_override into a generic SW feature overrideMarc Zyngier
Disabling KASLR from the command line is implemented as a feature override. Repaint it slightly so that it can further be used as more generic infrastructure for SW override purposes. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20230609162200.2024064-4-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-12arm64: Update Documentation/arm referencesJonathan Corbet
The Arm documentation has moved to Documentation/arch/arm; update references under arch/arm64 to match. Cc: Will Deacon <will@kernel.org> Cc: linux-arm-kernel@lists.infradead.org Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-06-09arm64: enable perf events based hard lockup detectorDouglas Anderson
With the recent feature added to enable perf events to use pseudo NMIs as interrupts on platforms which support GICv3 or later, its now been possible to enable hard lockup detector (or NMI watchdog) on arm64 platforms. So enable corresponding support. One thing to note here is that normally lockup detector is initialized just after the early initcalls but PMU on arm64 comes up much later as device_initcall(). To cope with that, override arch_perf_nmi_is_available() to let the watchdog framework know PMU not ready, and inform the framework to re-initialize lockup detection once PMU has been initialized. [dianders@chromium.org: only HAVE_HARDLOCKUP_DETECTOR_PERF if the PMU config is enabled] Link: https://lkml.kernel.org/r/20230523073952.1.I60217a63acc35621e13f10be16c0cd7c363caf8c@changeid Link: https://lkml.kernel.org/r/20230519101840.v5.18.Ia44852044cdcb074f387e80df6b45e892965d4a1@changeid Co-developed-by: Sumit Garg <sumit.garg@linaro.org> Signed-off-by: Sumit Garg <sumit.garg@linaro.org> Co-developed-by: Pingfan Liu <kernelfans@gmail.com> Signed-off-by: Pingfan Liu <kernelfans@gmail.com> Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen-Yu Tsai <wens@csie.org> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Colin Cross <ccross@android.com> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Guenter Roeck <groeck@chromium.org> Cc: Ian Rogers <irogers@google.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masayoshi Mizuma <msys.mizuma@gmail.com> Cc: Matthias Kaehlcke <mka@chromium.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com> Cc: Ricardo Neri <ricardo.neri@intel.com> Cc: Stephane Eranian <eranian@google.com> Cc: Stephen Boyd <swboyd@chromium.org> Cc: Tzung-Bi Shih <tzungbi@chromium.org> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09arm64: add hw_nmi_get_sample_period for preparation of lockup detectorLecopzer Chen
Set safe maximum CPU frequency to 5 GHz in case a particular platform doesn't implement cpufreq driver. Although, architecture doesn't put any restrictions on maximum frequency but 5 GHz seems to be safe maximum given the available Arm CPUs in the market which are clocked much less than 5 GHz. On the other hand, we can't make it much higher as it would lead to a large hard-lockup detection timeout on parts which are running slower (eg. 1GHz on Developerbox) and doesn't possess a cpufreq driver. Link: https://lkml.kernel.org/r/20230519101840.v5.17.Ia9d02578e89c3f44d3cb12eec8b0176603c8ab2f@changeid Co-developed-by: Sumit Garg <sumit.garg@linaro.org> Signed-off-by: Sumit Garg <sumit.garg@linaro.org> Co-developed-by: Pingfan Liu <kernelfans@gmail.com> Signed-off-by: Pingfan Liu <kernelfans@gmail.com> Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen-Yu Tsai <wens@csie.org> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Colin Cross <ccross@android.com> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Guenter Roeck <groeck@chromium.org> Cc: Ian Rogers <irogers@google.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masayoshi Mizuma <msys.mizuma@gmail.com> Cc: Matthias Kaehlcke <mka@chromium.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com> Cc: Ricardo Neri <ricardo.neri@intel.com> Cc: Stephane Eranian <eranian@google.com> Cc: Stephen Boyd <swboyd@chromium.org> Cc: Tzung-Bi Shih <tzungbi@chromium.org> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09mm/gup: remove vmas parameter from get_user_pages_remote()Lorenzo Stoakes
The only instances of get_user_pages_remote() invocations which used the vmas parameter were for a single page which can instead simply look up the VMA directly. In particular:- - __update_ref_ctr() looked up the VMA but did nothing with it so we simply remove it. - __access_remote_vm() was already using vma_lookup() when the original lookup failed so by doing the lookup directly this also de-duplicates the code. We are able to perform these VMA operations as we already hold the mmap_lock in order to be able to call get_user_pages_remote(). As part of this work we add get_user_page_vma_remote() which abstracts the VMA lookup, error handling and decrementing the page reference count should the VMA lookup fail. This forms part of a broader set of patches intended to eliminate the vmas parameter altogether. [akpm@linux-foundation.org: avoid passing NULL to PTR_ERR] Link: https://lkml.kernel.org/r/d20128c849ecdbf4dd01cc828fcec32127ed939a.1684350871.git.lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> (for arm64) Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> (for s390) Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Christian König <christian.koenig@amd.com> Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Sakari Ailus <sakari.ailus@linux.intel.com> Cc: Sean Christopherson <seanjc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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>
2023-06-07arm64: syscall: unmask DAIF for tracing statusGuo Hui
The following code: static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, const syscall_fn_t syscall_table[]) { ... if (!has_syscall_work(flags) && !IS_ENABLED(CONFIG_DEBUG_RSEQ)) { local_daif_mask(); flags = read_thread_flags(); -------------------------------- A if (!has_syscall_work(flags) && !(flags & _TIF_SINGLESTEP)) return; local_daif_restore(DAIF_PROCCTX); } trace_exit: syscall_trace_exit(regs); ------- B } 1. The flags in the if conditional statement should be used in the same way as the flags in the function syscall_trace_exit, because DAIF is not shielded in the function syscall_trace_exit, so when the flags are obtained in line A of the code, there is no need to shield DAIF. Don't care about the modification of flags after line A. 2. Masking DAIF caused syscall performance to deteriorate by about 10%. The Unixbench single core syscall performance data is as follows: Machine: Kunpeng 920 Mask DAIF: System Call Overhead 1172314.1 lps (10.0 s, 7 samples) System Benchmarks Partial Index BASELINE RESULT INDEX System Call Overhead 15000.0 1172314.1 781.5 ======== System Benchmarks Index Score (Partial Only) 781.5 Unmask DAIF: System Call Overhead 1287944.6 lps (10.0 s, 7 samples) System Benchmarks Partial Index BASELINE RESULT INDEX System Call Overhead 15000.0 1287944.6 858.6 ======== System Benchmarks Index Score (Partial Only) 858.6 Rationale from Mark Rutland as for why this is safe: This masking is an artifact of the old "ret_fast_syscall" assembly that was converted to C in commit: f37099b6992a0b81 ("arm64: convert syscall trace logic to C") The assembly would mask DAIF, check the thread flags, and fall through to kernel_exit without unmasking if no tracing was needed. The conversion copied this masking into the C version, though this wasn't strictly necessary. As (in general) thread flags can be manipulated by other threads, it's not safe to manipulate the thread flags with plain reads and writes, and since commit: 342b3808786518ce ("arm64: Snapshot thread flags") ... we use read_thread_flags() to read the flags atomically. With this, there is no need to mask DAIF transiently around reading the flags, as we only decide whether to trace while DAIF is masked, and the actual tracing occurs with DAIF unmasked. When el0_svc_common() returns its caller will unconditionally mask DAIF via exit_to_user_mode(), so the masking is redundant. Signed-off-by: Guo Hui <guohui@uniontech.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20230526024715.8773-1-guohui@uniontech.com [catalin.marinas@arm.com: updated comment with Mark's rationale] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-07arm64: cpufeature: fold cpus_set_cap() into update_cpu_capabilities()Mark Rutland
We only use cpus_set_cap() in update_cpu_capabilities(), where we open-code an analgous update to boot_cpucaps. Due to the way the cpucap_ptrs[] array is initialized, we know that the capability number cannot be greater than or equal to ARM64_NCAPS, so the warning is superfluous. Fold cpus_set_cap() into update_cpu_capabilities(), matching what we do for the boot_cpucaps, and making the relationship between the two a bit clearer. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230607164846.3967305-5-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-07arm64: cpufeature: use cpucap namingMark Rutland
To more clearly align the various users of the cpucap enumeration, this patch changes the cpufeature code to use the term `cpucap` in favour of `cpu_hwcap`. This more clearly aligns with other users of the cpucaps, and avoids confusion with the ELF hwcaps. There should be no functional change as a result of this patch; this is purely a renaming exercise. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230607164846.3967305-4-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-07arm64: alternatives: use cpucap namingMark Rutland
To more clearly align the various users of the cpucap enumeration, this patch changes the alternative code to use the term `cpucap` in favour of `feature`. The alternative_has_feature_{likely,unlikely}() functions are renamed to alternative_has_cap_<likely,unlikely}() to more clearly align with the cpus_have_{const_,}cap() helpers. At the same time remove the stale comment referring to the "ARM64_CB bit", which is evidently a typo for ARM64_CB_PATCH, which was removed in commit: 4c0bd995d73ed889 ("arm64: alternatives: have callbacks take a cap") There should be no functional change as a result of this patch; this is purely a renaming exercise. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230607164846.3967305-3-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-07arm64: standardise cpucap bitmap namesMark Rutland
The 'cpu_hwcaps' and 'boot_capabilities' bitmaps are bitmaps have the same enumerated bits, but are named wildly differently for no good reason. The terms 'hwcaps' and 'capabilities' have become ambiguous over time (e.g. due to clashes with ELF hwcaps and the structures used to manage feature detection), and it would be nicer to use 'cpucaps', matching the <asm/cpucaps.h> header the enumerated bit indices are defined in. While this isn't a functional problem, it makes the code harder than necessary to understand, and hard to extend with related functionality (e.g. per-cpu cpucap bitmaps). To that end, this patch renames `boot_capabilities` to `boot_cpucaps` and `cpu_hwcaps` to `system_cpucaps`. This more clearly indicates the relationship between the two and aligns with terminology used elsewhere in our feature management code. This change was scripted with: | find . -type f -name '*.[chS]' -print0 | \ | xargs -0 sed -i 's/\<boot_capabilities\>/boot_cpucaps/' | find . -type f -name '*.[chS]' -print0 | \ | xargs -0 sed -i 's/\<cpu_hwcaps\>/system_cpucaps/' ... and the instance of "cpu_hwcap" (without a trailing "s") in <asm/mmu_context.h> corrected manually to "system_cpucaps". Subsequent patches will adjust the naming of related functions to better align with the `cpucap` naming. There should be no functional change as a result of this patch; this is purely a renaming exercise. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230607164846.3967305-2-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-06arm64: module: rework module VA range selectionMark Rutland
Currently, the modules region is 128M in size, which is a problem for some large modules. Shanker reports [1] that the NVIDIA GPU driver alone can consume 110M of module space in some configurations. We'd like to make the modules region a full 2G such that we can always make use of a 2G range. It's possible to build kernel images which are larger than 128M in some configurations, such as when many debug options are selected and many drivers are built in. In these configurations, we can't legitimately select a base for a 128M module region, though we currently select a value for which allocation will fail. It would be nicer to have a diagnostic message in this case. Similarly, in theory it's possible to build a kernel image which is larger than 2G and which cannot support modules. While this isn't likely to be the case for any realistic kernel deplyed in the field, it would be nice if we could print a diagnostic in this case. This patch reworks the module VA range selection to use a 2G range, and improves handling of cases where we cannot select legitimate module regions. We now attempt to select a 128M region and a 2G region: * The 128M region is selected such that modules can use direct branches (with JUMP26/CALL26 relocations) to branch to kernel code and other modules, and so that modules can reference data and text (using PREL32 relocations) anywhere in the kernel image and other modules. This region covers the entire kernel image (rather than just the text) to ensure that all PREL32 relocations are in range even when the kernel data section is absurdly large. Where we cannot allocate from this region, we'll fall back to the full 2G region. * The 2G region is selected such that modules can use direct branches with PLTs to branch to kernel code and other modules, and so that modules can use reference data and text (with PREL32 relocations) in the kernel image and other modules. This region covers the entire kernel image, and the 128M region (if one is selected). The two module regions are randomized independently while ensuring the constraints described above. [1] https://lore.kernel.org/linux-arm-kernel/159ceeab-09af-3174-5058-445bc8dcf85b@nvidia.com/ Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Cc: Shanker Donthineni <sdonthineni@nvidia.com> Cc: Will Deacon <will@kernel.org> Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> Link: https://lore.kernel.org/r/20230530110328.2213762-7-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-06arm64: module: mandate MODULE_PLTSMark Rutland
Contemporary kernels and modules can be relatively large, especially when common debug options are enabled. Using GCC 12.1.0, a v6.3-rc7 defconfig kernel is ~38M, and with PROVE_LOCKING + KASAN_INLINE enabled this expands to ~117M. Shanker reports [1] that the NVIDIA GPU driver alone can consume 110M of module space in some configurations. Both KASLR and ARM64_ERRATUM_843419 select MODULE_PLTS, so anyone wanting a kernel to have KASLR or run on Cortex-A53 will have MODULE_PLTS selected. This is the case in defconfig and distribution kernels (e.g. Debian, Android, etc). Practically speaking, this means we're very likely to need MODULE_PLTS and while it's almost guaranteed that MODULE_PLTS will be selected, it is possible to disable support, and we have to maintain some awkward special cases for such unusual configurations. This patch removes the MODULE_PLTS config option, with the support code always enabled if MODULES is selected. This results in a slight simplification, and will allow for further improvement in subsequent patches. For any config which currently selects MODULE_PLTS, there will be no functional change as a result of this patch. [1] https://lore.kernel.org/linux-arm-kernel/159ceeab-09af-3174-5058-445bc8dcf85b@nvidia.com/ Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Cc: Shanker Donthineni <sdonthineni@nvidia.com> Cc: Will Deacon <will@kernel.org> Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> Link: https://lore.kernel.org/r/20230530110328.2213762-6-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-06arm64: module: move module randomization to module.cMark Rutland
When CONFIG_RANDOMIZE_BASE=y, module_alloc_base is a variable which is configured by kaslr_module_init() in kaslr.c, and otherwise it is an expression defined in module.h. As kaslr_module_init() is no longer tightly coupled with the KASLR initialization code, we can centralize this in module.c. This patch moves kaslr_module_init() to module.c, making module_alloc_base a static variable, and removing redundant includes from kaslr.c. For the defintion of struct arm64_ftr_override we must include <asm/cpufeature.h>, which was previously included transitively via another header. 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: Will Deacon <will@kernel.org> Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> Link: https://lore.kernel.org/r/20230530110328.2213762-5-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-06arm64: kaslr: split kaslr/module initializationMark Rutland
Currently kaslr_init() handles a mixture of detecting/announcing whether KASLR is enabled, and randomizing the module region depending on whether KASLR is enabled. To make it easier to rework the module region initialization, split the KASLR initialization into two steps: * kaslr_init() determines whether KASLR should be enabled, and announces this choice, recording this to a new global boolean variable. This is called from setup_arch() just before the existing call to kaslr_requires_kpti() so that this will always provide the expected result. * kaslr_module_init() randomizes the module region when required. This is called as a subsys_initcall, where we previously called kaslr_init(). As a bonus, moving the KASLR reporting earlier makes it easier to spot and permits it to be logged via earlycon, making it easier to debug any issues that could be triggered by KASLR. Booting a v6.4-rc1 kernel with this patch applied, the log looks like: | EFI stub: Booting Linux Kernel... | EFI stub: Generating empty DTB | EFI stub: Exiting boot services... | [ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x000f0510] | [ 0.000000] Linux version 6.4.0-rc1-00006-g4763a8f8aeb3 (mark@lakrids) (aarch64-linux-gcc (GCC) 12.1.0, GNU ld (GNU Binutils) 2.38) #2 SMP PREEMPT Tue May 9 11:03:37 BST 2023 | [ 0.000000] KASLR enabled | [ 0.000000] earlycon: pl11 at MMIO 0x0000000009000000 (options '') | [ 0.000000] printk: bootconsole [pl11] enabled Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Cc: Will Deacon <will@kernel.org> Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> Link: https://lore.kernel.org/r/20230530110328.2213762-4-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-06arm64: module: remove old !KASAN_VMALLOC logicMark Rutland
Historically, KASAN could be selected with or without KASAN_VMALLOC, and we had to be very careful where to place modules when KASAN_VMALLOC was not selected. However, since commit: f6f37d9320a11e90 ("arm64: select KASAN_VMALLOC for SW/HW_TAGS modes") Selecting CONFIG_KASAN on arm64 will also select CONFIG_KASAN_VMALLOC, and so the logic for handling CONFIG_KASAN without CONFIG_KASAN_VMALLOC is redundant and can be removed. Note: the "kasan.vmalloc={on,off}" option which only exists for HW_TAGS changes whether the vmalloc region is given non-match-all tags, and does not affect the page table manipulation code. The VM_DEFER_KMEMLEAK flag was only necessary for !CONFIG_KASAN_VMALLOC as described in its introduction in commit: 60115fa54ad7b913 ("mm: defer kmemleak object creation of module_alloc()") ... and therefore it can also be removed. Remove the redundant logic for !CONFIG_KASAN_VMALLOC. At the same time, add the missing braces around the multi-line conditional block in arch/arm64/kernel/module.c. Suggested-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Cc: Alexander Potapenko <glider@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Will Deacon <will@kernel.org> Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> Link: https://lore.kernel.org/r/20230530110328.2213762-2-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-06arm64: lockdep: enable checks for held locks when returning to userspaceEric Chan
Currently arm64 doesn't use CONFIG_GENERIC_ENTRY and doesn't call lockdep_sys_exit() when returning to userspace. This means that lockdep won't check for held locks when returning to userspace, which would be useful to detect kernel bugs. Call lockdep_sys_exit() when returning to userspace, enabling checking for held locks. At the same time, rename arm64's prepare_exit_to_user_mode() to exit_to_user_mode_prepare() to more clearly align with the naming in the generic entry code. Signed-off-by: Eric Chan <ericchancf@google.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20230531090909.357047-1-ericchancf@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-06arm64: transfer permission indirection settings to EL2Joey Gouly
Copy the EL1 registers: TCR2_EL1, PIR_EL1, PIRE0_EL1, such that PIE is also enabled for EL2. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20230606145859.697944-18-joey.gouly@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-06arm64: add PTE_UXN/PTE_WRITE to SWAPPER_*_FLAGSJoey Gouly
With PIE enabled, the swapper PTEs would have a Permission Indirection Index (PIIndex) of 0. A PIIndex of 0 is not currently used by any other PTEs. To avoid using index 0 specifically for the swapper PTEs, mark them as PTE_UXN and PTE_WRITE, so that they map to a PAGE_KERNEL_EXEC equivalent. This also adds PTE_WRITE to KPTI_NG_PTE_FLAGS, which was tested by booting with kpti=on. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20230606145859.697944-12-joey.gouly@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-06arm64: cpufeature: add Permission Indirection Extension cpucapJoey Gouly
This indicates if the system supports PIE. This is a CPUCAP_BOOT_CPU_FEATURE as the boot CPU will enable PIE if it has it, so secondary CPUs must also have this feature. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20230606145859.697944-8-joey.gouly@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-06arm64: cpufeature: add TCR2 cpucapJoey Gouly
This capability indicates if the system supports the TCR2_ELx system register. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20230606145859.697944-7-joey.gouly@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-06arm64: cpufeature: add system register ID_AA64MMFR3Joey Gouly
Add new system register ID_AA64MMFR3 to the cpufeature infrastructure. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20230606145859.697944-6-joey.gouly@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-05arm64: mops: allow disabling MOPS from the kernel command lineKristina Martsenko
Make it possible to disable the MOPS extension at runtime using the kernel command line. This can be useful for testing or working around hardware issues. For example it could be used to test new memory copy routines that do not use MOPS instructions (e.g. from Arm Optimized Routines). Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20230509142235.3284028-11-kristina.martsenko@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-06-05arm64: mops: detect and enable FEAT_MOPSKristina Martsenko
The Arm v8.8/9.3 FEAT_MOPS feature provides new instructions that perform a memory copy or set. Wire up the cpufeature code to detect the presence of FEAT_MOPS and enable it. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20230509142235.3284028-10-kristina.martsenko@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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>
2023-06-05arm64: cpufeature: detect FEAT_HCXKristina Martsenko
Detect if the system has the new HCRX_EL2 register added in ARMv8.7/9.2, so that subsequent patches can check for its presence. KVM currently relies on the register being present on all CPUs (or none), so the kernel will panic if that is not the case. Fortunately no such systems currently exist, but this can be revisited if they appear. Note that the kernel will not panic if CONFIG_KVM is disabled. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20230509142235.3284028-3-kristina.martsenko@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-05-26arm64/cpufeature: Use helper for ECV CNTPOFF cpufeatureMark Brown
The newly added support for ECV CNTPOFF open codes the recently added helper ARM64_CPUID_FIELDS(), make use of the helper. No functional change. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20230523-arm64-ecv-helper-v1-1-506dfb5fb199@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-05-25arm64: signal: include asm/exception.hArnd Bergmann
The do_notify_resume() is in a header that is not included for the definition, which causes a W=1 warning: arch/arm64/kernel/signal.c:1280:6: error: no previous prototype for 'do_notify_resume' [-Werror=missing-prototypes] 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/20230516160642.523862-14-arnd@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-05-25arm64: module-plts: inline linux/moduleloader.hArnd Bergmann
module_frob_arch_sections() is declared in moduleloader.h, but that is not included before the definition: arch/arm64/kernel/module-plts.c:286:5: error: no previous prototype for 'module_frob_arch_sections' [-Werror=missing-prototypes] 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/20230516160642.523862-11-arnd@kernel.org 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>
2023-05-25arm64: cpuidle: fix #ifdef for acpi functionsArnd Bergmann
The acpi_processor_ffh_lpi_* functions are defined whenever CONFIG_ACPI is enabled, but only called and declared when CONFIG_ACPI_PROCESSOR_IDLE is also enabled. Without that, a W=1 build triggers missing-prototope warnings, so the #ifdef needs to be adapted: arch/arm64/kernel/cpuidle.c:60:5: error: no previous prototype for 'acpi_processor_ffh_lpi_probe' [-Werror=missing-prototypes] arch/arm64/kernel/cpuidle.c:65:15: error: no previous prototype for 'acpi_processor_ffh_lpi_enter' [-Werror=missing-prototypes] 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/20230516160642.523862-8-arnd@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-05-25arm64: move cpu_suspend_set_dbg_restorer() prototype to headerArnd Bergmann
The cpu_suspend_set_dbg_restorer() function is called by the hw_breakpoint code but defined in another file. Since the declaration is in the same file as the caller, the compiler warns about the definition without a prior prototype: arch/arm64/kernel/suspend.c:35:13: error: no previous prototype for 'cpu_suspend_set_dbg_restorer' [-Werror=missing-prototypes] Move it into the corresponding header instead to avoid the warning. 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/20230516160642.523862-5-arnd@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-05-25arm64: entry: Simplify tramp_alias macro and tramp_exit routineArd Biesheuvel
The tramp_alias macro constructs the virtual alias of a symbol in the trampoline text mapping, based on its kernel text address, and does so in a way that is more convoluted than necessary. So let's simplify that. Also, now that the address of the vector table is kept in a per-CPU variable, there is no need to defer the load and the assignment of VBAR_EL1 to tramp_exit(). This means we can use a PC-relative reference to the per-CPU variable instead of storing its absolute address in a global variable in the trampoline rodata. And given that tramp_alias no longer needs a temp register, this means we can restore X30 earlier as well, and only leave X29 for tramp_exit() to restore. While at it, give some related symbols static linkage, considering that they are only referenced from the object file that defines them. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230418143604.1176437-3-ardb@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-05-25arm64: entry: Preserve/restore X29 even for compat tasksArd Biesheuvel
Currently, the KPTI trampoline code for returning to user space takes care to only preserve X29 into FAR_EL1 for native tasks, as compat tasks don't have access to this register anyway, and so preserving it is not necessary. It also means it does not need to be restored, and so we have two code paths for returning back to user space: the native one that restores X29 from FAR_EL1, and the compat one that leaves X29 clobbered, containing the value of TTBR1_EL1, which carries a physical address pointing somewhere into the kernel image. This is needlessly complex, and given that FAR_EL1 becomes UNKNOWN after an exception return anway, the only benefit of avoiding the preserve and restore is that we can skip the system register write and read. So let's simplify this, and collapse the two code paths into one that always preserves X29 into FAR_EL1, and always restores it again after the TTBR switch. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230418143604.1176437-2-ardb@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-05-21KVM: arm64: Relax trapping of CTR_EL0 when FEAT_EVT is availableMarc Zyngier
CTR_EL0 can often be used in userspace, and it would be nice if KVM didn't have to emulate it unnecessarily. While it isn't possible to trap the cache configuration registers independently from CTR_EL0 in the base ARMv8.0 architecture, FEAT_EVT allows these cache configuration registers (CCSIDR_EL1, CCSIDR2_EL1, CLIDR_EL1 and CSSELR_EL1) to be trapped independently by setting HCR_EL2.TID4. Switch to using TID4 instead of TID2 in the cases where FEAT_EVT is available *and* that KVM doesn't need to sanitise CTR_EL0 to paper over mismatched cache configurations. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230515170016.965378-1-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-05-16arm64: mte: Do not set PG_mte_tagged if tags were not initializedPeter Collingbourne
The mte_sync_page_tags() function sets PG_mte_tagged if it initializes page tags. Then we return to mte_sync_tags(), which sets PG_mte_tagged again. At best, this is redundant. However, it is possible for mte_sync_page_tags() to return without having initialized tags for the page, i.e. in the case where check_swap is true (non-compound page), is_swap_pte(old_pte) is false and pte_is_tagged is false. So at worst, we set PG_mte_tagged on a page with uninitialized tags. This can happen if, for example, page migration causes a PTE for an untagged page to be replaced. If the userspace program subsequently uses mprotect() to enable PROT_MTE for that page, the uninitialized tags will be exposed to userspace. Fix it by removing the redundant call to set_page_mte_tagged(). Fixes: e059853d14ca ("arm64: mte: Fix/clarify the PG_mte_tagged semantics") Signed-off-by: Peter Collingbourne <pcc@google.com> Cc: <stable@vger.kernel.org> # 6.1 Link: https://linux-review.googlesource.com/id/Ib02d004d435b2ed87603b858ef7480f7b1463052 Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Link: https://lore.kernel.org/r/20230420214327.2357985-1-pcc@google.com Signed-off-by: Will Deacon <will@kernel.org>
2023-05-16arm64: vdso: Pass (void *) to virt_to_page()Linus Walleij
Like the other calls in this function virt_to_page() expects a pointer, not an integer. However since many architectures implement virt_to_pfn() as a macro, this function becomes polymorphic and accepts both a (unsigned long) and a (void *). Fix this up with an explicit cast. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: http://lists.infradead.org/pipermail/linux-arm-kernel/2023-May/832583.html Signed-off-by: Will Deacon <will@kernel.org>
2023-05-15arm64: smp: Switch to hotplug core state synchronizationThomas Gleixner
Switch to the CPU hotplug core state tracking and synchronization mechanim. No functional change intended. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205256.690926018@linutronix.de
2023-05-04Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: "A few arm64 fixes that came in during the merge window for -rc1. The main thing is restoring the pointer authentication hwcaps, which disappeared during some recent refactoring - Fix regression in CPU erratum workaround when disabling the MMU - Fix detection of pointer authentication hwcaps - Avoid writeable, executable ELF sections in vmlinux" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: lds: move .got section out of .text arm64: kernel: remove SHF_WRITE|SHF_EXECINSTR from .idmap.text arm64: cpufeature: Fix pointer auth hwcaps arm64: Fix label placement in record_mmu_state()
2023-05-02arm64: lds: move .got section out of .textFangrui Song
Currently, the .got section is placed within the output section .text. However, when .got is non-empty, the SHF_WRITE flag is set for .text when linked by lld. GNU ld recognizes .text as a special section and ignores the SHF_WRITE flag. By renaming .text, we can also get the SHF_WRITE flag. The kernel has performed R_AARCH64_RELATIVE resolving very early, and can then assume that .got is read-only. Let's move .got to the vmlinux_rodata pseudo-segment. As Ard Biesheuvel notes: "This matters to consumers of the vmlinux ELF representation of the kernel image, such as syzkaller, which disregards writable PT_LOAD segments when resolving code symbols. The kernel itself does not care about this distinction, but given that the GOT contains data and not code, it does not require executable permissions, and therefore does not belong in .text to begin with." Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Fangrui Song <maskray@google.com> Link: https://lore.kernel.org/r/20230502074105.1541926-1-maskray@google.com Signed-off-by: Will Deacon <will@kernel.org>
2023-05-02arm64: kernel: remove SHF_WRITE|SHF_EXECINSTR from .idmap.textndesaulniers@google.com
commit d54170812ef1 ("arm64: fix .idmap.text assertion for large kernels") modified some of the section assembler directives that declare .idmap.text to be SHF_ALLOC instead of SHF_ALLOC|SHF_WRITE|SHF_EXECINSTR. This patch fixes up the remaining stragglers that were left behind. Add Fixes tag so that this doesn't precede related change in stable. Fixes: d54170812ef1 ("arm64: fix .idmap.text assertion for large kernels") Reported-by: Greg Thelen <gthelen@google.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Link: https://lore.kernel.org/r/20230428-awx-v2-1-b197ffa16edc@google.com Signed-off-by: Will Deacon <will@kernel.org>