user/sven/linux.git/include/linux/sched, branch v5.3.14

sched/membarrier: Call sync_core only before usermode for same mm

2019-10-11T16:36:43Z

[ Upstream commit 2840cf02fae627860156737e83326df354ee4ec6 ] When the prev and next task's mm change, switch_mm() provides the core serializing guarantees before returning to usermode. The only case where an explicit core serialization is needed is when the scheduler keeps the same mm for prev and next. Suggested-by: Oleg Nesterov Signed-off-by: Mathieu Desnoyers Signed-off-by: Peter Zijlstra (Intel) Cc: Chris Metcalf Cc: Christoph Lameter Cc: Eric W. Biederman Cc: Kirill Tkhai Cc: Linus Torvalds Cc: Mike Galbraith Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Russell King - ARM Linux admin Cc: Thomas Gleixner Link: https://lkml.kernel.org/r/20190919173705.2181-4-mathieu.desnoyers@efficios.com Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin

sched/fair: Don't free p->numa_faults with concurrent readers

2019-07-25T13:37:04Z

When going through execve(), zero out the NUMA fault statistics instead of freeing them. During execve, the task is reachable through procfs and the scheduler. A concurrent /proc/*/sched reader can read data from a freed ->numa_faults allocation (confirmed by KASAN) and write it back to userspace. I believe that it would also be possible for a use-after-free read to occur through a race between a NUMA fault and execve(): task_numa_fault() can lead to task_numa_compare(), which invokes task_weight() on the currently running task of a different CPU. Another way to fix this would be to make ->numa_faults RCU-managed or add extra locking, but it seems easier to wipe the NUMA fault statistics on execve. Signed-off-by: Jann Horn Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Petr Mladek Cc: Sergey Senozhatsky Cc: Thomas Gleixner Cc: Will Deacon Fixes: 82727018b0d3 ("sched/numa: Call task_numa_free() from do_execve()") Link: https://lkml.kernel.org/r/20190716152047.14424-1-jannh@google.com Signed-off-by: Ingo Molnar

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

2019-07-20T17:20:27Z

Pull more KVM updates from Paolo Bonzini: "Mostly bugfixes, but also: - s390 support for KVM selftests - LAPIC timer offloading to housekeeping CPUs - Extend an s390 optimization for overcommitted hosts to all architectures - Debugging cleanups and improvements" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (25 commits) KVM: x86: Add fixed counters to PMU filter KVM: nVMX: do not use dangling shadow VMCS after guest reset KVM: VMX: dump VMCS on failed entry KVM: x86/vPMU: refine kvm_pmu err msg when event creation failed KVM: s390: Use kvm_vcpu_wake_up in kvm_s390_vcpu_wakeup KVM: Boost vCPUs that are delivering interrupts KVM: selftests: Remove superfluous define from vmx.c KVM: SVM: Fix detection of AMD Errata 1096 KVM: LAPIC: Inject timer interrupt via posted interrupt KVM: LAPIC: Make lapic timer unpinned KVM: x86/vPMU: reset pmc->counter to 0 for pmu fixed_counters KVM: nVMX: Ignore segment base for VMX memory operand when segment not FS or GS kvm: x86: ioapic and apic debug macros cleanup kvm: x86: some tsc debug cleanup kvm: vmx: fix coccinelle warnings x86: kvm: avoid constant-conversion warning x86: kvm: avoid -Wsometimes-uninitized warning KVM: x86: expose AVX512_BF16 feature to guest KVM: selftests: enable pgste option for the linker on s390 KVM: selftests: Move kvm_create_max_vcpus test to generic code ...

KVM: LAPIC: Inject timer interrupt via posted interrupt

2019-07-20T07:00:40Z

Dedicated instances are currently disturbed by unnecessary jitter due to the emulated lapic timers firing on the same pCPUs where the vCPUs reside. There is no hardware virtual timer on Intel for guest like ARM, so both programming timer in guest and the emulated timer fires incur vmexits. This patch tries to avoid vmexit when the emulated timer fires, at least in dedicated instance scenario when nohz_full is enabled. In that case, the emulated timers can be offload to the nearest busy housekeeping cpus since APICv has been found for several years in server processors. The guest timer interrupt can then be injected via posted interrupts, which are delivered by the housekeeping cpu once the emulated timer fires. The host should tuned so that vCPUs are placed on isolated physical processors, and with several pCPUs surplus for busy housekeeping. If disabled mwait/hlt/pause vmexits keep the vCPUs in non-root mode, ~3% redis performance benefit can be observed on Skylake server, and the number of external interrupt vmexits drops substantially. Without patch VM-EXIT Samples Samples% Time% Min Time Max Time Avg time EXTERNAL_INTERRUPT 42916 49.43% 39.30% 0.47us 106.09us 0.71us ( +- 1.09% ) While with patch: VM-EXIT Samples Samples% Time% Min Time Max Time Avg time EXTERNAL_INTERRUPT 6871 9.29% 2.96% 0.44us 57.88us 0.72us ( +- 4.02% ) Cc: Paolo Bonzini Cc: Radim Krčmář Cc: Marcelo Tosatti Signed-off-by: Wanpeng Li Signed-off-by: Paolo Bonzini

Merge branch 'akpm' (patches from Andrew)

2019-07-17T15:58:04Z

Merge more updates from Andrew Morton: "VM: - z3fold fixes and enhancements by Henry Burns and Vitaly Wool - more accurate reclaimed slab caches calculations by Yafang Shao - fix MAP_UNINITIALIZED UAPI symbol to not depend on config, by Christoph Hellwig - !CONFIG_MMU fixes by Christoph Hellwig - new novmcoredd parameter to omit device dumps from vmcore, by Kairui Song - new test_meminit module for testing heap and pagealloc initialization, by Alexander Potapenko - ioremap improvements for huge mappings, by Anshuman Khandual - generalize kprobe page fault handling, by Anshuman Khandual - device-dax hotplug fixes and improvements, by Pavel Tatashin - enable synchronous DAX fault on powerpc, by Aneesh Kumar K.V - add pte_devmap() support for arm64, by Robin Murphy - unify locked_vm accounting with a helper, by Daniel Jordan - several misc fixes core/lib: - new typeof_member() macro including some users, by Alexey Dobriyan - make BIT() and GENMASK() available in asm, by Masahiro Yamada - changed LIST_POISON2 on x86_64 to 0xdead000000000122 for better code generation, by Alexey Dobriyan - rbtree code size optimizations, by Michel Lespinasse - convert struct pid count to refcount_t, by Joel Fernandes get_maintainer.pl: - add --no-moderated switch to skip moderated ML's, by Joe Perches misc: - ptrace PTRACE_GET_SYSCALL_INFO interface - coda updates - gdb scripts, various" [ Using merge message suggestion from Vlastimil Babka, with some editing - Linus ] * emailed patches from Andrew Morton : (100 commits) fs/select.c: use struct_size() in kmalloc() mm: add account_locked_vm utility function arm64: mm: implement pte_devmap support mm: introduce ARCH_HAS_PTE_DEVMAP mm: clean up is_device_*_page() definitions mm/mmap: move common defines to mman-common.h mm: move MAP_SYNC to asm-generic/mman-common.h device-dax: "Hotremove" persistent memory that is used like normal RAM mm/hotplug: make remove_memory() interface usable device-dax: fix memory and resource leak if hotplug fails include/linux/lz4.h: fix spelling and copy-paste errors in documentation ipc/mqueue.c: only perform resource calculation if user valid include/asm-generic/bug.h: fix "cut here" for WARN_ON for __WARN_TAINT architectures scripts/gdb: add helpers to find and list devices scripts/gdb: add lx-genpd-summary command drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl kernel/pid.c: convert struct pid count to refcount_t drivers/rapidio/devices/rio_mport_cdev.c: NUL terminate some strings select: shift restore_saved_sigmask_unless() into poll_select_copy_remaining() select: change do_poll() to return -ERESTARTNOHAND rather than -EINTR ...

signal: simplify set_user_sigmask/restore_user_sigmask

2019-07-17T02:23:24Z

task->saved_sigmask and ->restore_sigmask are only used in the ret-from- syscall paths. This means that set_user_sigmask() can save ->blocked in ->saved_sigmask and do set_restore_sigmask() to indicate that ->blocked was modified. This way the callers do not need 2 sigset_t's passed to set/restore and restore_user_sigmask() renamed to restore_saved_sigmask_unless() turns into the trivial helper which just calls restore_saved_sigmask(). Link: http://lkml.kernel.org/r/20190606113206.GA9464@redhat.com Signed-off-by: Oleg Nesterov Cc: Deepa Dinamani Cc: Arnd Bergmann Cc: Jens Axboe Cc: Davidlohr Bueso Cc: Eric Wong Cc: Jason Baron Cc: Thomas Gleixner Cc: Al Viro Cc: Eric W. Biederman Cc: David Laight Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

signal: reorder struct sighand_struct

2019-07-17T02:23:24Z

struct sighand_struct::siglock field is the most used field by far, put it first so that is can be accessed without IMM8 or IMM32 encoding on x86_64. Space savings (on trimmed down VM test config): add/remove: 0/0 grow/shrink: 8/68 up/down: 49/-1147 (-1098) Function old new delta complete_signal 512 533 +21 do_signalfd4 335 346 +11 __cleanup_sighand 39 43 +4 unhandled_signal 49 52 +3 prepare_signal 692 695 +3 ignore_signals 37 40 +3 __tty_check_change.part 248 251 +3 ksys_unshare 780 781 +1 sighand_ctor 33 29 -4 ptrace_trap_notify 60 56 -4 sigqueue_free 98 91 -7 run_posix_cpu_timers 1389 1382 -7 proc_pid_status 2448 2441 -7 proc_pid_limits 344 337 -7 posix_cpu_timer_rearm 222 215 -7 posix_cpu_timer_get 249 242 -7 kill_pid_info_as_cred 243 236 -7 freeze_task 197 190 -7 flush_old_exec 1873 1866 -7 do_task_stat 3363 3356 -7 do_send_sig_info 98 91 -7 do_group_exit 147 140 -7 init_sighand 2088 2080 -8 do_notify_parent_cldstop 399 391 -8 signalfd_cleanup 50 41 -9 do_notify_parent 557 545 -12 __send_signal 1029 1017 -12 ptrace_stop 590 577 -13 get_signal 1576 1563 -13 __lock_task_sighand 112 99 -13 zap_pid_ns_processes 391 377 -14 update_rlimit_cpu 78 64 -14 tty_signal_session_leader 413 399 -14 tty_open_proc_set_tty 149 135 -14 tty_jobctrl_ioctl 936 922 -14 set_cpu_itimer 339 325 -14 ptrace_resume 226 212 -14 ptrace_notify 110 96 -14 proc_clear_tty 81 67 -14 posix_cpu_timer_del 229 215 -14 kernel_sigaction 156 142 -14 getrusage 977 963 -14 get_current_tty 98 84 -14 force_sigsegv 89 75 -14 force_sig_info 205 191 -14 flush_signals 83 69 -14 flush_itimer_signals 85 71 -14 do_timer_create 1120 1106 -14 do_sigpending 88 74 -14 do_signal_stop 537 523 -14 cgroup_init_fs_context 644 630 -14 call_usermodehelper_exec_async 402 388 -14 calculate_sigpending 58 44 -14 __x64_sys_timer_delete 248 234 -14 __set_current_blocked 80 66 -14 __ptrace_unlink 310 296 -14 __ptrace_detach.part 187 173 -14 send_sigqueue 362 347 -15 get_cpu_itimer 214 199 -15 signalfd_poll 175 159 -16 dequeue_signal 340 323 -17 do_getitimer 192 174 -18 release_task.part 1060 1040 -20 ptrace_peek_siginfo 408 387 -21 posix_cpu_timer_set 827 806 -21 exit_signals 437 416 -21 do_sigaction 541 520 -21 do_setitimer 485 464 -21 disassociate_ctty.part 545 517 -28 __x64_sys_rt_sigtimedwait 721 679 -42 __x64_sys_ptrace 1319 1277 -42 ptrace_request 1828 1782 -46 signalfd_read 507 459 -48 wait_consider_task 2027 1971 -56 do_coredump 3672 3616 -56 copy_process.part 6936 6871 -65 Link: http://lkml.kernel.org/r/20190503192800.GA18004@avx2 Signed-off-by: Alexey Dobriyan Cc: Michal Hocko Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

clone: fix CLONE_PIDFD support

2019-07-14T18:36:12Z

The introduction of clone3 syscall accidentally broke CLONE_PIDFD support in traditional clone syscall on compat x86 and those architectures that use do_fork to implement clone syscall. This bug was found by strace test suite. Link: https://strace.io/logs/strace/2019-07-12 Fixes: 7f192e3cd316 ("fork: add clone3") Bisected-and-tested-by: Anatoly Pugachev Signed-off-by: Dmitry V. Levin Link: https://lore.kernel.org/r/20190714162047.GB10389@altlinux.org Signed-off-by: Christian Brauner

Merge tag 'clone3-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

2019-07-11T17:09:44Z

Pull clone3 system call from Christian Brauner: "This adds the clone3 syscall which is an extensible successor to clone after we snagged the last flag with CLONE_PIDFD during the 5.2 merge window for clone(). It cleanly supports all of the flags from clone() and thus all legacy workloads. There are few user visible differences between clone3 and clone. First, CLONE_DETACHED will cause EINVAL with clone3 so we can reuse this flag. Second, the CSIGNAL flag is deprecated and will cause EINVAL to be reported. It is superseeded by a dedicated "exit_signal" argument in struct clone_args thus freeing up even more flags. And third, clone3 gives CLONE_PIDFD a dedicated return argument in struct clone_args instead of abusing CLONE_PARENT_SETTID's parent_tidptr argument. The clone3 uapi is designed to be easy to handle on 32- and 64 bit: /* uapi */ struct clone_args { __aligned_u64 flags; __aligned_u64 pidfd; __aligned_u64 child_tid; __aligned_u64 parent_tid; __aligned_u64 exit_signal; __aligned_u64 stack; __aligned_u64 stack_size; __aligned_u64 tls; }; and a separate kernel struct is used that uses proper kernel typing: /* kernel internal */ struct kernel_clone_args { u64 flags; int __user *pidfd; int __user *child_tid; int __user *parent_tid; int exit_signal; unsigned long stack; unsigned long stack_size; unsigned long tls; }; The system call comes with a size argument which enables the kernel to detect what version of clone_args userspace is passing in. clone3 validates that any additional bytes a given kernel does not know about are set to zero and that the size never exceeds a page. A nice feature is that this patchset allowed us to cleanup and simplify various core kernel codepaths in kernel/fork.c by making the internal _do_fork() function take struct kernel_clone_args even for legacy clone(). This patch also unblocks the time namespace patchset which wants to introduce a new CLONE_TIMENS flag. Note, that clone3 has only been wired up for x86{_32,64}, arm{64}, and xtensa. These were the architectures that did not require special massaging. Other architectures treat fork-like system calls individually and after some back and forth neither Arnd nor I felt confident that we dared to add clone3 unconditionally to all architectures. We agreed to leave this up to individual architecture maintainers. This is why there's an additional patch that introduces __ARCH_WANT_SYS_CLONE3 which any architecture can set once it has implemented support for clone3. The patch also adds a cond_syscall(clone3) for architectures such as nios2 or h8300 that generate their syscall table by simply including asm-generic/unistd.h. The hope is to get rid of __ARCH_WANT_SYS_CLONE3 and cond_syscall() rather soon" * tag 'clone3-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: arch: handle arches who do not yet define clone3 arch: wire-up clone3() syscall fork: add clone3

Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2019-07-09T04:48:15Z

Pull force_sig() argument change from Eric Biederman: "A source of error over the years has been that force_sig has taken a task parameter when it is only safe to use force_sig with the current task. The force_sig function is built for delivering synchronous signals such as SIGSEGV where the userspace application caused a synchronous fault (such as a page fault) and the kernel responded with a signal. Because the name force_sig does not make this clear, and because the force_sig takes a task parameter the function force_sig has been abused for sending other kinds of signals over the years. Slowly those have been fixed when the oopses have been tracked down. This set of changes fixes the remaining abusers of force_sig and carefully rips out the task parameter from force_sig and friends making this kind of error almost impossible in the future" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits) signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus signal: Remove the signal number and task parameters from force_sig_info signal: Factor force_sig_info_to_task out of force_sig_info signal: Generate the siginfo in force_sig signal: Move the computation of force into send_signal and correct it. signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal signal: Remove the task parameter from force_sig_fault signal: Use force_sig_fault_to_task for the two calls that don't deliver to current signal: Explicitly call force_sig_fault on current signal/unicore32: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from __do_user_fault signal/arm: Remove tsk parameter from ptrace_break signal/nds32: Remove tsk parameter from send_sigtrap signal/riscv: Remove tsk parameter from do_trap signal/sh: Remove tsk parameter from force_sig_info_fault signal/um: Remove task parameter from send_sigtrap signal/x86: Remove task parameter from send_sigtrap signal: Remove task parameter from force_sig_mceerr signal: Remove task parameter from force_sig signal: Remove task parameter from force_sigsegv ...