lwn.git/arch/s390/include/asm, branch header-removal

s390/pci: fix zpci_zdev_put() on reserve

2021-10-04T07:49:10+00:00

Since commit 2a671f77ee49 ("s390/pci: fix use after free of zpci_dev") the reference count of a zpci_dev is incremented between pcibios_add_device() and pcibios_release_device() which was supposed to prevent the zpci_dev from being freed while the common PCI code has access to it. It was missed however that the handling of zPCI availability events assumed that once zpci_zdev_put() was called no later availability event would still see the device. With the previously mentioned commit however this assumption no longer holds and we must make sure that we only drop the initial long-lived reference the zPCI subsystem holds exactly once. Do so by introducing a zpci_device_reserved() function that handles when a device is reserved. Here we make sure the zpci_dev will not be considered for further events by removing it from the zpci_list. This also means that the device actually stays in the ZPCI_FN_STATE_RESERVED state between the time we know it has been reserved and the final reference going away. We thus need to consider it a real state instead of just a conceptual state after the removal. The final cleanup of PCI resources, removal from zbus, and destruction of the IOMMU stays in zpci_release_device() to make sure holders of the reference do see valid data until the release. Fixes: 2a671f77ee49 ("s390/pci: fix use after free of zpci_dev") Cc: stable@vger.kernel.org Signed-off-by: Niklas Schnelle Signed-off-by: Vasily Gorbik

s390/qeth: fix deadlock during failing recovery

2021-09-22T03:02:24+00:00

Commit 0b9902c1fcc5 ("s390/qeth: fix deadlock during recovery") removed taking discipline_mutex inside qeth_do_reset(), fixing potential deadlocks. An error path was missed though, that still takes discipline_mutex and thus has the original deadlock potential. Intermittent deadlocks were seen when a qeth channel path is configured offline, causing a race between qeth_do_reset and ccwgroup_remove. Call qeth_set_offline() directly in the qeth_do_reset() error case and then a new variant of ccwgroup_set_offline(), without taking discipline_mutex. Fixes: b41b554c1ee7 ("s390/qeth: fix locking for discipline setup / removal") Signed-off-by: Alexandra Winter Reviewed-by: Julian Wiedmann Signed-off-by: Julian Wiedmann Signed-off-by: Jakub Kicinski

Merge tag 's390-5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2021-09-09T19:55:12+00:00

Pull more s390 updates from Heiko Carstens: "Except for the xpram device driver removal it is all about fixes and cleanups. - Fix topology update on cpu hotplug, so notifiers see expected masks. This bug was uncovered with SCHED_CORE support. - Fix stack unwinding so that the correct number of entries are omitted like expected by common code. This fixes KCSAN selftests. - Add kmemleak annotation to stack_alloc to avoid false positive kmemleak warnings. - Avoid layering violation in common I/O code and don't unregister subchannel from child-drivers. - Remove xpram device driver for which no real use case exists since the kernel is 64 bit only. Also all hypervisors got required support removed in the meantime, which means the xpram device driver is dead code. - Fix -ENODEV handling of clp_get_state in our PCI code. - Enable KFENCE in debug defconfig. - Cleanup hugetlbfs s390 specific Kconfig dependency. - Quite a lot of trivial fixes to get rid of "W=1" warnings, and and other simple cleanups" * tag 's390-5.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: hugetlbfs: s390 is always 64bit s390/ftrace: remove incorrect __va usage s390/zcrypt: remove incorrect kernel doc indicators scsi: zfcp: fix kernel doc comments s390/sclp: add __nonstring annotation s390/hmcdrv_ftp: fix kernel doc comment s390: remove xpram device driver s390/pci: read clp_list_pci_req only once s390/pci: fix clp_get_state() handling of -ENODEV s390/cio: fix kernel doc comment s390/ctrlchar: fix kernel doc comment s390/con3270: use proper type for tasklet function s390/cpum_cf: move array from header to C file s390/mm: fix kernel doc comments s390/topology: fix topology information when calling cpu hotplug notifiers s390/unwind: use current_frame_address() to unwind current task s390/configs: enable CONFIG_KFENCE in debug_defconfig s390/entry: make oklabel within CHKSTG macro local s390: add kmemleak annotation in stack_alloc() s390/cio: dont unregister subchannel from child-drivers

arch: remove compat_alloc_user_space

2021-09-08T22:32:35+00:00

All users of compat_alloc_user_space() and copy_in_user() have been removed from the kernel, only a few functions in sparc remain that can be changed to calling arch_copy_in_user() instead. Link: https://lkml.kernel.org/r/20210727144859.4150043-7-arnd@kernel.org Signed-off-by: Arnd Bergmann Reviewed-by: Christoph Hellwig Cc: Al Viro Cc: Benjamin Herrenschmidt Cc: Borislav Petkov Cc: Catalin Marinas Cc: Christian Borntraeger Cc: Christoph Hellwig Cc: "David S. Miller" Cc: Eric Biederman Cc: Feng Tang Cc: Heiko Carstens Cc: Helge Deller Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: "James E.J. Bottomley" Cc: Michael Ellerman Cc: Paul Mackerras Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

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

2021-09-07T20:40:51+00:00

Pull KVM updates from Paolo Bonzini: "ARM: - Page ownership tracking between host EL1 and EL2 - Rely on userspace page tables to create large stage-2 mappings - Fix incompatibility between pKVM and kmemleak - Fix the PMU reset state, and improve the performance of the virtual PMU - Move over to the generic KVM entry code - Address PSCI reset issues w.r.t. save/restore - Preliminary rework for the upcoming pKVM fixed feature - A bunch of MM cleanups - a vGIC fix for timer spurious interrupts - Various cleanups s390: - enable interpretation of specification exceptions - fix a vcpu_idx vs vcpu_id mixup x86: - fast (lockless) page fault support for the new MMU - new MMU now the default - increased maximum allowed VCPU count - allow inhibit IRQs on KVM_RUN while debugging guests - let Hyper-V-enabled guests run with virtualized LAPIC as long as they do not enable the Hyper-V "AutoEOI" feature - fixes and optimizations for the toggling of AMD AVIC (virtualized LAPIC) - tuning for the case when two-dimensional paging (EPT/NPT) is disabled - bugfixes and cleanups, especially with respect to vCPU reset and choosing a paging mode based on CR0/CR4/EFER - support for 5-level page table on AMD processors Generic: - MMU notifier invalidation callbacks do not take mmu_lock unless necessary - improved caching of LRU kvm_memory_slot - support for histogram statistics - add statistics for halt polling and remote TLB flush requests" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (210 commits) KVM: Drop unused kvm_dirty_gfn_invalid() KVM: x86: Update vCPU's hv_clock before back to guest when tsc_offset is adjusted KVM: MMU: mark role_regs and role accessors as maybe unused KVM: MIPS: Remove a "set but not used" variable x86/kvm: Don't enable IRQ when IRQ enabled in kvm_wait KVM: stats: Add VM stat for remote tlb flush requests KVM: Remove unnecessary export of kvm_{inc,dec}_notifier_count() KVM: x86/mmu: Move lpage_disallowed_link further "down" in kvm_mmu_page KVM: x86/mmu: Relocate kvm_mmu_page.tdp_mmu_page for better cache locality Revert "KVM: x86: mmu: Add guest physical address check in translate_gpa()" KVM: x86/mmu: Remove unused field mmio_cached in struct kvm_mmu_page kvm: x86: Increase KVM_SOFT_MAX_VCPUS to 710 kvm: x86: Increase MAX_VCPUS to 1024 kvm: x86: Set KVM_MAX_VCPU_ID to 4*KVM_MAX_VCPUS KVM: VMX: avoid running vmx_handle_exit_irqoff in case of emulation KVM: x86/mmu: Don't freak out if pml5_root is NULL on 4-level host KVM: s390: index kvm->arch.idle_mask by vcpu_idx KVM: s390: Enable specification exception interpretation KVM: arm64: Trim guest debug exception handling KVM: SVM: Add 5-level page table support for SVM ...

s390/cpum_cf: move array from header to C file

2021-09-07T11:38:41+00:00

Move array from header to C file to avoid that it gets defined in every C file where the header is included: In file included from arch/s390/kernel/perf_cpum_cf_common.c:19: ./arch/s390/include/asm/cpu_mcf.h:27:18: warning: ‘cpumf_ctr_ctl’ defined but not used [-Wunused-const-variable=] 27 | static const u64 cpumf_ctr_ctl[CPUMF_CTR_SET_MAX] = { | ^~~~~~~~~~~~~ Signed-off-by: Heiko Carstens

s390/topology: fix topology information when calling cpu hotplug notifiers

2021-09-07T11:38:41+00:00

The cpu hotplug notifiers are called without updating the core/thread masks when a new CPU is added. This causes problems with code setting up data structures in a cpu hotplug notifier, and relying on that later in normal code. This caused a crash in the new core scheduling code (SCHED_CORE), where rq->core was set up in a notifier depending on cpu masks. To fix this, add a cpu_setup_mask which is used in update_cpu_masks() instead of the cpu_online_mask to determine whether the cpu masks should be set for a certain cpu. Also move update_cpu_masks() to update the masks before calling notify_cpu_starting() so that the notifiers are seeing the updated masks. Signed-off-by: Sven Schnelle Cc: [hca@linux.ibm.com: get rid of cpu_online_mask handling] Signed-off-by: Heiko Carstens

s390/unwind: use current_frame_address() to unwind current task

2021-09-07T11:38:27+00:00

current_stack_pointer() simply returns current value of %r15. If current_stack_pointer() caller allocates stack (which is the case in unwind code) %r15 points to a stack frame allocated for callees, meaning current_stack_pointer() caller (e.g. stack_trace_save) will end up in the stacktrace. This is not expected by stack_trace_save*() callers and causes problems. current_frame_address() on the other hand returns function stack frame address, which matches %r15 upon function invocation. Using it in get_stack_pointer() makes it more aligned with x86 implementation (according to BACKTRACE_SELF_TEST output) and meets stack_trace_save*() caller's expectations, notably KCSAN. Also make sure unwind_start is always inlined. Reported-by: Nathan Chancellor Suggested-by: Marco Elver Signed-off-by: Vasily Gorbik Tested-by: Marco Elver Tested-by: Nathan Chancellor Link: https://lore.kernel.org/r/patch.git-04dd26be3043.your-ad-here.call-01630504868-ext-6188@work.hours Signed-off-by: Heiko Carstens

Merge tag 'kvmarm-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2021-09-06T10:34:48+00:00

KVM/arm64 updates for 5.15 - Page ownership tracking between host EL1 and EL2 - Rely on userspace page tables to create large stage-2 mappings - Fix incompatibility between pKVM and kmemleak - Fix the PMU reset state, and improve the performance of the virtual PMU - Move over to the generic KVM entry code - Address PSCI reset issues w.r.t. save/restore - Preliminary rework for the upcoming pKVM fixed feature - A bunch of MM cleanups - a vGIC fix for timer spurious interrupts - Various cleanups

Merge tag 'kvm-s390-next-5.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

2021-09-06T10:33:40+00:00

KVM: s390: Fix and feature for 5.15 - enable interpretion of specification exceptions - fix a vcpu_idx vs vcpu_id mixup