linux-dev/arch/s390/include/asm/uaccess.h, branch linus/master

s390/uaccess: whitespace cleanup

2022-06-01T10:03:17Z

Whitespace cleanup to get rid if some checkpatch findings, but mainly to have consistent coding style within the header file again. Signed-off-by: Heiko Carstens

s390/uaccess: use noreturn instead of attribute__((noreturn))

2022-06-01T10:03:17Z

Signed-off-by: Heiko Carstens

s390/uaccess: use exception handler to zero result on get_user() failure

2022-06-01T10:03:17Z

Historically the uaccess code pre-initializes the result of get_user() (and now also __get_kernel_nofault()) to zero and uses the result as input parameter for inline assemblies. This is different to what most, if not all, other architectures are doing, which set the result to zero within the exception handler in case of a fault. Use the new extable mechanism and handle zeroing of the result within the exception handler in case of a fault. Signed-off-by: Heiko Carstens

s390/uaccess: use symbolic names for inline assembler operands

2022-06-01T10:03:16Z

Make code easier to read by using symbolic names. Signed-off-by: Heiko Carstens

Merge tag 's390-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2022-03-25T17:01:34Z

Pull s390 updates from Vasily Gorbik: - Raise minimum supported machine generation to z10, which comes with various cleanups and code simplifications (usercopy/spectre mitigation/etc). - Rework extables and get rid of anonymous out-of-line fixups. - Page table helpers cleanup. Add set_pXd()/set_pte() helper functions. Covert pte_val()/pXd_val() macros to functions. - Optimize kretprobe handling by avoiding extra kprobe on __kretprobe_trampoline. - Add support for CEX8 crypto cards. - Allow to trigger AP bus rescan via writing to /sys/bus/ap/scans. - Add CONFIG_EXPOLINE_EXTERN option to build the kernel without COMDAT group sections which simplifies kpatch support. - Always use the packed stack layout and extend kernel unwinder tests. - Add sanity checks for ftrace code patching. - Add s390dbf debug log for the vfio_ap device driver. - Various virtual vs physical address confusion fixes. - Various small fixes and improvements all over the code. * tag 's390-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (69 commits) s390/test_unwind: add kretprobe tests s390/kprobes: Avoid additional kprobe in kretprobe handling s390: convert ".insn" encoding to instruction names s390: assume stckf is always present s390/nospec: move to single register thunks s390: raise minimum supported machine generation to z10 s390/uaccess: Add copy_from/to_user_key functions s390/nospec: align and size extern thunks s390/nospec: add an option to use thunk-extern s390/nospec: generate single register thunks if possible s390/pci: make zpci_set_irq()/zpci_clear_irq() static s390: remove unused expoline to BC instructions s390/irq: use assignment instead of cast s390/traps: get rid of magic cast for per code s390/traps: get rid of magic cast for program interruption code s390/signal: fix typo in comments s390/asm-offsets: remove unused defines s390/test_unwind: avoid build warning with W=1 s390: remove .fixup section s390/bpf: encode register within extable entry ...

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2022-03-24T18:58:57Z

Pull kvm updates from Paolo Bonzini: "ARM: - Proper emulation of the OSLock feature of the debug architecture - Scalibility improvements for the MMU lock when dirty logging is on - New VMID allocator, which will eventually help with SVA in VMs - Better support for PMUs in heterogenous systems - PSCI 1.1 support, enabling support for SYSTEM_RESET2 - Implement CONFIG_DEBUG_LIST at EL2 - Make CONFIG_ARM64_ERRATUM_2077057 default y - Reduce the overhead of VM exit when no interrupt is pending - Remove traces of 32bit ARM host support from the documentation - Updated vgic selftests - Various cleanups, doc updates and spelling fixes RISC-V: - Prevent KVM_COMPAT from being selected - Optimize __kvm_riscv_switch_to() implementation - RISC-V SBI v0.3 support s390: - memop selftest - fix SCK locking - adapter interruptions virtualization for secure guests - add Claudio Imbrenda as maintainer - first step to do proper storage key checking x86: - Continue switching kvm_x86_ops to static_call(); introduce static_call_cond() and __static_call_ret0 when applicable. - Cleanup unused arguments in several functions - Synthesize AMD 0x80000021 leaf - Fixes and optimization for Hyper-V sparse-bank hypercalls - Implement Hyper-V's enlightened MSR bitmap for nested SVM - Remove MMU auditing - Eager splitting of page tables (new aka "TDP" MMU only) when dirty page tracking is enabled - Cleanup the implementation of the guest PGD cache - Preparation for the implementation of Intel IPI virtualization - Fix some segment descriptor checks in the emulator - Allow AMD AVIC support on systems with physical APIC ID above 255 - Better API to disable virtualization quirks - Fixes and optimizations for the zapping of page tables: - Zap roots in two passes, avoiding RCU read-side critical sections that last too long for very large guests backed by 4 KiB SPTEs. - Zap invalid and defunct roots asynchronously via concurrency-managed work queue. - Allowing yielding when zapping TDP MMU roots in response to the root's last reference being put. - Batch more TLB flushes with an RCU trick. Whoever frees the paging structure now holds RCU as a proxy for all vCPUs running in the guest, i.e. to prolongs the grace period on their behalf. It then kicks the the vCPUs out of guest mode before doing rcu_read_unlock(). Generic: - Introduce __vcalloc and use it for very large allocations that need memcg accounting" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits) KVM: use kvcalloc for array allocations KVM: x86: Introduce KVM_CAP_DISABLE_QUIRKS2 kvm: x86: Require const tsc for RT KVM: x86: synthesize CPUID leaf 0x80000021h if useful KVM: x86: add support for CPUID leaf 0x80000021 KVM: x86: do not use KVM_X86_OP_OPTIONAL_RET0 for get_mt_mask Revert "KVM: x86/mmu: Zap only TDP MMU leafs in kvm_zap_gfn_range()" kvm: x86/mmu: Flush TLB before zap_gfn_range releases RCU KVM: arm64: fix typos in comments KVM: arm64: Generalise VM features into a set of flags KVM: s390: selftests: Add error memop tests KVM: s390: selftests: Add more copy memop tests KVM: s390: selftests: Add named stages for memop test KVM: s390: selftests: Add macro as abstraction for MEM_OP KVM: s390: selftests: Split memop tests KVM: s390x: fix SCK locking RISC-V: KVM: Implement SBI HSM suspend call RISC-V: KVM: Add common kvm_riscv_vcpu_wfi() function RISC-V: Add SBI HSM suspend related defines RISC-V: KVM: Implement SBI v0.3 SRST extension ...

s390: raise minimum supported machine generation to z10

2022-03-10T14:58:17Z

Machine generations up to z9 (released in May 2006) have been officially out of service for several years now (z9 end of service - January 31, 2019). No distributions build kernels supporting those old machine generations anymore, except Debian, which seems to pick the oldest supported generation. The team supporting Debian on s390 has been notified about the change. Raising minimum supported machine generation to z10 helps to reduce maintenance cost and effectively remove code, which is not getting enough testing coverage due to lack of older hardware and distributions support. Besides that this unblocks some optimization opportunities and allows to use wider instruction set in asm files for future features implementation. Due to this change spectre mitigation and usercopy implementations could be drastically simplified and many newer instructions could be converted from ".insn" encoding to instruction names. Acked-by: Ilya Leoshkevich Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/uaccess: Add copy_from/to_user_key functions

2022-03-10T14:58:17Z

Add copy_from/to_user_key functions, which perform storage key checking. These functions can be used by KVM for emulating instructions that need to be key checked. These functions differ from their non _key counterparts in include/linux/uaccess.h only in the additional key argument and must be kept in sync with those. Since the existing uaccess implementation on s390 makes use of move instructions that support having an additional access key supplied, we can implement raw_copy_from/to_user_key by enhancing the existing implementation. Signed-off-by: Janis Schoetterl-Glausch Acked-by: Heiko Carstens Reviewed-by: Christian Borntraeger Acked-by: Janosch Frank Link: https://lore.kernel.org/r/20220211182215.2730017-2-scgl@linux.ibm.com Signed-off-by: Vasily Gorbik

s390/extable: add dedicated uaccess handler

2022-03-07T23:33:00Z

This is more or less a combination of commit 2e77a62cb3a6 ("arm64: extable: add a dedicated uaccess handler") and commit 4b5305decc84 ("x86/extable: Extend extable functionality"). To describe the problem that needs to solved let's cite the full arm64 commit message: ------ 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. ------ Acked-by: Alexander Gordeev Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/extable: move EX_TABLE define to asm-extable.h

2022-03-07T23:33:00Z

Follow arm64 and riscv and move the EX_TABLE define to asm-extable.h which is a lot less generic than the current linkage.h. Also make sure that all files which contain EX_TABLE usages actually include the new header file. This should make sure that the files always compile and there won't be any random compile breakage due to other header file dependencies. Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

linux-dev/arch/s390/include/asm/uaccess.h, branch linus/master

s390/uaccess: whitespace cleanup

s390/uaccess: use __noreturn instead of __attribute__((noreturn))

s390/uaccess: use exception handler to zero result on get_user() failure

s390/uaccess: use symbolic names for inline assembler operands

Merge tag 's390-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

s390: raise minimum supported machine generation to z10

s390/uaccess: Add copy_from/to_user_key functions

s390/extable: add dedicated uaccess handler

s390/extable: move EX_TABLE define to asm-extable.h

s390/uaccess: use noreturn instead of attribute__((noreturn))