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2019-09-20Merge tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuildLinus Torvalds1-1/+2
Pull Kbuild updates from Masahiro Yamada: - add modpost warn exported symbols marked as 'static' because 'static' and EXPORT_SYMBOL is an odd combination - break the build early if gold linker is used - optimize the Bison rule to produce .c and .h files by a single pattern rule - handle PREEMPT_RT in the module vermagic and UTS_VERSION - warn CONFIG options leaked to the user-space except existing ones - make single targets work properly - rebuild modules when module linker scripts are updated - split the module final link stage into scripts/Makefile.modfinal - fix the missed error code in merge_config.sh - improve the error message displayed on the attempt of the O= build in unclean source tree - remove 'clean-dirs' syntax - disable -Wimplicit-fallthrough warning for Clang - add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC - remove ARCH_{CPP,A,C}FLAGS variables - add $(BASH) to run bash scripts - change *CFLAGS_<basetarget>.o to take the relative path to $(obj) instead of the basename - stop suppressing Clang's -Wunused-function warnings when W=1 - fix linux/export.h to avoid genksyms calculating CRC of trimmed exported symbols - misc cleanups * tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (63 commits) genksyms: convert to SPDX License Identifier for lex.l and parse.y modpost: use __section in the output to *.mod.c modpost: use MODULE_INFO() for __module_depends export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols export.h: remove defined(__KERNEL__), which is no longer needed kbuild: allow Clang to find unused static inline functions for W=1 build kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN kbuild: refactor scripts/Makefile.extrawarn merge_config.sh: ignore unwanted grep errors kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj) modpost: add NOFAIL to strndup modpost: add guid_t type definition kbuild: add $(BASH) to run scripts with bash-extension kbuild: remove ARCH_{CPP,A,C}FLAGS kbuild,arc: add CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3 for ARC kbuild: Do not enable -Wimplicit-fallthrough for clang for now kbuild: clean up subdir-ymn calculation in Makefile.clean kbuild: remove unneeded '+' marker from cmd_clean kbuild: remove clean-dirs syntax kbuild: check clean srctree even earlier ...
2019-09-17Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-1/+1
Pull core timer updates from Thomas Gleixner: "Timers and timekeeping updates: - A large overhaul of the posix CPU timer code which is a preparation for moving the CPU timer expiry out into task work so it can be properly accounted on the task/process. An update to the bogus permission checks will come later during the merge window as feedback was not complete before heading of for travel. - Switch the timerqueue code to use cached rbtrees and get rid of the homebrewn caching of the leftmost node. - Consolidate hrtimer_init() + hrtimer_init_sleeper() calls into a single function - Implement the separation of hrtimers to be forced to expire in hard interrupt context even when PREEMPT_RT is enabled and mark the affected timers accordingly. - Implement a mechanism for hrtimers and the timer wheel to protect RT against priority inversion and live lock issues when a (hr)timer which should be canceled is currently executing the callback. Instead of infinitely spinning, the task which tries to cancel the timer blocks on a per cpu base expiry lock which is held and released by the (hr)timer expiry code. - Enable the Hyper-V TSC page based sched_clock for Hyper-V guests resulting in faster access to timekeeping functions. - Updates to various clocksource/clockevent drivers and their device tree bindings. - The usual small improvements all over the place" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits) posix-cpu-timers: Fix permission check regression posix-cpu-timers: Always clear head pointer on dequeue hrtimer: Add a missing bracket and hide `migration_base' on !SMP posix-cpu-timers: Make expiry_active check actually work correctly posix-timers: Unbreak CONFIG_POSIX_TIMERS=n build tick: Mark sched_timer to expire in hard interrupt context hrtimer: Add kernel doc annotation for HRTIMER_MODE_HARD x86/hyperv: Hide pv_ops access for CONFIG_PARAVIRT=n posix-cpu-timers: Utilize timerqueue for storage posix-cpu-timers: Move state tracking to struct posix_cputimers posix-cpu-timers: Deduplicate rlimit handling posix-cpu-timers: Remove pointless comparisons posix-cpu-timers: Get rid of 64bit divisions posix-cpu-timers: Consolidate timer expiry further posix-cpu-timers: Get rid of zero checks rlimit: Rewrite non-sensical RLIMIT_CPU comment posix-cpu-timers: Respect INFINITY for hard RTTIME limit posix-cpu-timers: Switch thread group sampling to array posix-cpu-timers: Restructure expiry array posix-cpu-timers: Remove cputime_expires ...
2019-09-16Merge branch 'x86-entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds4-24/+53
Pull x86 entry updates from Ingo Molnar: "This contains x32 and compat syscall improvements, the biggest one of which splits x32 syscalls into their own table, which allows new syscalls to share the x32 and x86-64 number - which turns the 512-547 special syscall numbers range into a legacy wart that won't be extended going forward" * 'x86-entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/syscalls: Split the x32 syscalls into their own table x86/syscalls: Disallow compat entries for all types of 64-bit syscalls x86/syscalls: Use the compat versions of rt_sigsuspend() and rt_sigprocmask() x86/syscalls: Make __X32_SYSCALL_BIT be unsigned long
2019-09-16Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-2/+2
Pull x86 asm updates from Ingo Molnar: - Add UMIP emulation/spoofing for 64-bit processes as well, because of Wine based gaming. - Clean up symbols/labels in low level asm code - Add an assembly optimized mul_u64_u32_div() implementation on x86-64. * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/umip: Add emulation (spoofing) for UMIP covered instructions in 64-bit processes as well x86/asm: Make some functions local labels x86/asm/suspend: Get rid of bogus_64_magic x86/math64: Provide a sane mul_u64_u32_div() implementation for x86_64
2019-09-16Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds4-8/+8
Pull scheduler updates from Ingo Molnar: - MAINTAINERS: Add Mark Rutland as perf submaintainer, Juri Lelli and Vincent Guittot as scheduler submaintainers. Add Dietmar Eggemann, Steven Rostedt, Ben Segall and Mel Gorman as scheduler reviewers. As perf and the scheduler is getting bigger and more complex, document the status quo of current responsibilities and interests, and spread the review pain^H^H^H^H fun via an increase in the Cc: linecount generated by scripts/get_maintainer.pl. :-) - Add another series of patches that brings the -rt (PREEMPT_RT) tree closer to mainline: split the monolithic CONFIG_PREEMPT dependencies into a new CONFIG_PREEMPTION category that will allow the eventual introduction of CONFIG_PREEMPT_RT. Still a few more hundred patches to go though. - Extend the CPU cgroup controller with uclamp.min and uclamp.max to allow the finer shaping of CPU bandwidth usage. - Micro-optimize energy-aware wake-ups from O(CPUS^2) to O(CPUS). - Improve the behavior of high CPU count, high thread count applications running under cpu.cfs_quota_us constraints. - Improve balancing with SCHED_IDLE (SCHED_BATCH) tasks present. - Improve CPU isolation housekeeping CPU allocation NUMA locality. - Fix deadline scheduler bandwidth calculations and logic when cpusets rebuilds the topology, or when it gets deadline-throttled while it's being offlined. - Convert the cpuset_mutex to percpu_rwsem, to allow it to be used from setscheduler() system calls without creating global serialization. Add new synchronization between cpuset topology-changing events and the deadline acceptance tests in setscheduler(), which were broken before. - Rework the active_mm state machine to be less confusing and more optimal. - Rework (simplify) the pick_next_task() slowpath. - Improve load-balancing on AMD EPYC systems. - ... and misc cleanups, smaller fixes and improvements - please see the Git log for more details. * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits) sched/psi: Correct overly pessimistic size calculation sched/fair: Speed-up energy-aware wake-ups sched/uclamp: Always use 'enum uclamp_id' for clamp_id values sched/uclamp: Update CPU's refcount on TG's clamp changes sched/uclamp: Use TG's clamps to restrict TASK's clamps sched/uclamp: Propagate system defaults to the root group sched/uclamp: Propagate parent clamps sched/uclamp: Extend CPU's cgroup controller sched/topology: Improve load balancing on AMD EPYC systems arch, ia64: Make NUMA select SMP sched, perf: MAINTAINERS update, add submaintainers and reviewers sched/fair: Use rq_lock/unlock in online_fair_sched_group cpufreq: schedutil: fix equation in comment sched: Rework pick_next_task() slow-path sched: Allow put_prev_task() to drop rq->lock sched/fair: Expose newidle_balance() sched: Add task_struct pointer to sched_class::set_curr_task sched: Rework CPU hotplug task selection sched/{rt,deadline}: Fix set_next_task vs pick_next_task sched: Fix kerneldoc comment for ia64_set_curr_task ...
2019-09-06x86/asm: Make some functions local labelsJiri Slaby1-2/+2
Boris suggests to make a local label (prepend ".L") to these functions to eliminate them from the symbol table. These are functions with very local names and really should not be visible anywhere. Note that objtool won't see these functions anymore (to generate ORC debug info). But all the functions are not annotated with ENDPROC, so they won't have objtool's attention anyway. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Cao jin <caoj.fnst@cn.fujitsu.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steve Winslow <swinslow@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Huang <wei@redhat.com> Cc: x86-ml <x86@kernel.org> Cc: Xiaoyao Li <xiaoyao.li@linux.intel.com> Link: https://lkml.kernel.org/r/20190906075550.23435-2-jslaby@suse.cz
2019-09-04kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj)Masahiro Yamada1-1/+2
Kbuild provides per-file compiler flag addition/removal: CFLAGS_<basetarget>.o CFLAGS_REMOVE_<basetarget>.o AFLAGS_<basetarget>.o AFLAGS_REMOVE_<basetarget>.o CPPFLAGS_<basetarget>.lds HOSTCFLAGS_<basetarget>.o HOSTCXXFLAGS_<basetarget>.o The <basetarget> is the filename of the target with its directory and suffix stripped. This syntax comes into a trouble when two files with the same basename appear in one Makefile, for example: obj-y += foo.o obj-y += dir/foo.o CFLAGS_foo.o := <some-flags> Here, the <some-flags> applies to both foo.o and dir/foo.o The real world problem is: scripts/kconfig/util.c scripts/kconfig/lxdialog/util.c Both files are compiled into scripts/kconfig/mconf, but only the latter should be given with the ncurses flags. It is more sensible to use the relative path to the Makefile, like this: obj-y += foo.o CFLAGS_foo.o := <some-flags> obj-y += dir/foo.o CFLAGS_dir/foo.o := <other-flags> At first, I attempted to replace $(basetarget) with $*. The $* variable is replaced with the stem ('%') part in a pattern rule. This works with most of cases, but does not for explicit rules. For example, arch/ia64/lib/Makefile reuses rule_as_o_S in its own explicit rules, so $* will be empty, resulting in ignoring the per-file AFLAGS. I introduced a new variable, target-stem, which can be used also from explicit rules. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Marc Zyngier <maz@kernel.org>
2019-08-23clocksource/drivers/hyperv: Allocate Hyper-V TSC page staticallyTianyu Lan1-1/+1
Prepare to add Hyper-V sched clock callback and move Hyper-V Reference TSC initialization much earlier in the boot process. Earlier initialization is needed so that it happens while the timestamp value is still 0 and no discontinuity in the timestamp will occur when pv_ops.time.sched_clock calculates its offset. The earlier initialization requires that the Hyper-V TSC page be allocated statically instead of with vmalloc(), so fixup the references to the TSC page and the method of getting its physical address. Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lkml.kernel.org/r/20190814123216.32245-2-Tianyu.Lan@microsoft.com
2019-07-31x86: Use CONFIG_PREEMPTIONThomas Gleixner4-8/+8
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same functionality which today depends on CONFIG_PREEMPT. Switch the entry code, preempt and kprobes conditionals over to CONFIG_PREEMPTION. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20190726212124.608488448@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-28Merge branch master from git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.gitThomas Gleixner9-121/+148
Pick up the spectre documentation so the Grand Schemozzle can be added.
2019-07-24x86/entry/32: Pass cr2 to do_async_page_fault()Matt Mullins1-4/+9
Commit a0d14b8909de ("x86/mm, tracing: Fix CR2 corruption") added the address parameter to do_async_page_fault(), but does not pass it from the 32-bit entry point. To plumb it through, factor-out common_exception_read_cr2 in the same fashion as common_exception, and uses it from both page_fault and async_page_fault. For a 32-bit KVM guest, this fixes: Run /sbin/init as init process Starting init: /sbin/init exists but couldn't execute it (error -14) Fixes: a0d14b8909de ("x86/mm, tracing: Fix CR2 corruption") Signed-off-by: Matt Mullins <mmullins@fb.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20190724042058.24506-1-mmullins@fb.com
2019-07-22x86/syscalls: Split the x32 syscalls into their own tableAndy Lutomirski3-20/+49
For unfortunate historical reasons, the x32 syscalls and the x86_64 syscalls are not all numbered the same. As an example, ioctl() is nr 16 on x86_64 but 514 on x32. This has potentially nasty consequences, since it means that there are two valid RAX values to do ioctl(2) and two invalid RAX values. The valid values are 16 (i.e. ioctl(2) using the x86_64 ABI) and (514 | 0x40000000) (i.e. ioctl(2) using the x32 ABI). The invalid values are 514 and (16 | 0x40000000). 514 will enter the "COMPAT_SYSCALL_DEFINE3(ioctl, ...)" entry point with in_compat_syscall() and in_x32_syscall() returning false, whereas (16 | 0x40000000) will enter the native entry point with in_compat_syscall() and in_x32_syscall() returning true. Both are bogus, and both will exercise code paths in the kernel and in any running seccomp filters that really ought to be unreachable. Splitting out the x32 syscalls into their own tables, allows both bogus invocations to return -ENOSYS. I've checked glibc, musl, and Bionic, and all of them appear to call syscalls with their correct numbers, so this change should have no effect on them. There is an added benefit going forward: new syscalls that need special handling on x32 can share the same number on x32 and x86_64. This means that the special syscall range 512-547 can be treated as a legacy wart instead of something that may need to be extended in the future. Also add a selftest to verify the new behavior. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/208024256b764312598f014ebfb0a42472c19354.1562185330.git.luto@kernel.org
2019-07-22x86/syscalls: Disallow compat entries for all types of 64-bit syscallsAndy Lutomirski1-2/+2
A "compat" entry in the syscall tables means to use a different entry on 32-bit and 64-bit builds. This only makes sense for syscalls that exist in the first place in 32-bit builds, so disallow it for anything other than i386. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/4b7565954c5a06530ac01d98cb1592538fd8ae51.1562185330.git.luto@kernel.org
2019-07-22x86/syscalls: Use the compat versions of rt_sigsuspend() and rt_sigprocmask()Andy Lutomirski1-2/+2
I'm working on some code that detects at build time if there's a COMPAT_SYSCALL_DEFINE() that is not referenced in the x86 syscall tables. It catches three offenders: rt_sigsuspend(), rt_sigprocmask(), and sendfile64(). For rt_sigsuspend() and rt_sigprocmask(), the only potential difference between the native and compat versions is that the compat version converts the sigset_t, but, on little endian architectures, the conversion is a no-op. This is why they both currently work on x86. To make the code more consistent, and to make the upcoming patches work, rewire x86 to use the compat vesions. sendfile64() is more complicated, and will be addressed separately. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/51643ac3157b5921eae0e172a8a0b1d953e68ebb.1562185330.git.luto@kernel.org
2019-07-20Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds3-99/+123
Pull x86 fixes from Thomas Gleixner: "A set of x86 specific fixes and updates: - The CR2 corruption fixes which store CR2 early in the entry code and hand the stored address to the fault handlers. - Revert a forgotten leftover of the dropped FSGSBASE series. - Plug a memory leak in the boot code. - Make the Hyper-V assist functionality robust by zeroing the shadow page. - Remove a useless check for dead processes with LDT - Update paravirt and VMware maintainers entries. - A few cleanup patches addressing various compiler warnings" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/entry/64: Prevent clobbering of saved CR2 value x86/hyper-v: Zero out the VP ASSIST PAGE on allocation x86, boot: Remove multiple copy of static function sanitize_boot_params() x86/boot/compressed/64: Remove unused variable x86/boot/efi: Remove unused variables x86/mm, tracing: Fix CR2 corruption x86/entry/64: Update comments and sanity tests for create_gap x86/entry/64: Simplify idtentry a little x86/entry/32: Simplify common_exception x86/paravirt: Make read_cr2() CALLEE_SAVE MAINTAINERS: Update PARAVIRT_OPS_INTERFACE and VMWARE_HYPERVISOR_INTERFACE x86/process: Delete useless check for dead process with LDT x86: math-emu: Hide clang warnings for 16-bit overflow x86/e820: Use proper booleans instead of 0/1 x86/apic: Silence -Wtype-limits compiler warnings x86/mm: Free sme_early_buffer after init x86/boot: Fix memory leak in default_get_smp_config() Revert "x86/ptrace: Prevent ptrace from clearing the FS/GS selector" and fix the test
2019-07-20Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-3/+2
Pull core fixes from Thomas Gleixner: - A collection of objtool fixes which address recent fallout partially exposed by newer toolchains, clang, BPF and general code changes. - Force USER_DS for user stack traces [ Note: the "objtool fixes" are not all to objtool itself, but for kernel code that triggers objtool warnings. Things like missing function size annotations, or code that confuses the unwinder etc. - Linus] * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits) objtool: Support conditional retpolines objtool: Convert insn type to enum objtool: Fix seg fault on bad switch table entry objtool: Support repeated uses of the same C jump table objtool: Refactor jump table code objtool: Refactor sibling call detection logic objtool: Do frame pointer check before dead end check objtool: Change dead_end_function() to return boolean objtool: Warn on zero-length functions objtool: Refactor function alias logic objtool: Track original function across branches objtool: Add mcsafe_handle_tail() to the uaccess safe list bpf: Disable GCC -fgcse optimization for ___bpf_prog_run() x86/uaccess: Remove redundant CLACs in getuser/putuser error paths x86/uaccess: Don't leak AC flag into fentry from mcsafe_handle_tail() x86/uaccess: Remove ELF function annotation from copy_user_handle_tail() x86/head/64: Annotate start_cpu0() as non-callable x86/entry: Fix thunk function ELF sizes x86/kvm: Don't call kvm_spurious_fault() from .fixup x86/kvm: Replace vmx_vmenter()'s call to kvm_spurious_fault() with UD2 ...
2019-07-20Merge tag 'kbuild-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuildLinus Torvalds1-3/+2
Pull more Kbuild updates from Masahiro Yamada: - match the directory structure of the linux-libc-dev package to that of Debian-based distributions - fix incorrect include/config/auto.conf generation when Kconfig creates it along with the .config file - remove misleading $(AS) from documents - clean up precious tag files by distclean instead of mrproper - add a new coccinelle patch for devm_platform_ioremap_resource migration - refactor module-related scripts to read modules.order instead of $(MODVERDIR)/*.mod files to get the list of created modules - remove MODVERDIR - update list of header compile-test - add -fcf-protection=none flag to avoid conflict with the retpoline flags when CONFIG_RETPOLINE=y - misc cleanups * tag 'kbuild-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits) kbuild: add -fcf-protection=none when using retpoline flags kbuild: update compile-test header list for v5.3-rc1 kbuild: split out *.mod out of {single,multi}-used-m rules kbuild: remove 'prepare1' target kbuild: remove the first line of *.mod files kbuild: create *.mod with full directory path and remove MODVERDIR kbuild: export_report: read modules.order instead of .tmp_versions/*.mod kbuild: modpost: read modules.order instead of $(MODVERDIR)/*.mod kbuild: modsign: read modules.order instead of $(MODVERDIR)/*.mod kbuild: modinst: read modules.order instead of $(MODVERDIR)/*.mod scsi: remove pointless $(MODVERDIR)/$(obj)/53c700.ver kbuild: remove duplication from modules.order in sub-directories kbuild: get rid of kernel/ prefix from in-tree modules.{order,builtin} kbuild: do not create empty modules.order in the prepare stage coccinelle: api: add devm_platform_ioremap_resource script kbuild: compile-test headers listed in header-test-m as well kbuild: remove unused hostcc-option kbuild: remove tag files by distclean instead of mrproper kbuild: add --hash-style= and --build-id unconditionally kbuild: get rid of misleading $(AS) from documents ...
2019-07-20x86/entry/64: Prevent clobbering of saved CR2 valueThomas Gleixner1-1/+10
The recent fix for CR2 corruption introduced a new way to reliably corrupt the saved CR2 value. CR2 is saved early in the entry code in RDX, which is the third argument to the fault handling functions. But it missed that between saving and invoking the fault handler enter_from_user_mode() can be called. RDX is a caller saved register so the invoked function can freely clobber it with the obvious consequences. The TRACE_IRQS_OFF call is safe as it calls through the thunk which preserves RDX, but TRACE_IRQS_OFF_DEBUG is not because it also calls into C-code outside of the thunk. Store CR2 in R12 instead which is a callee saved register and move R12 to RDX just before calling the fault handler. Fixes: a0d14b8909de ("x86/mm, tracing: Fix CR2 corruption") Reported-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1907201020540.1782@nanos.tec.linutronix.de
2019-07-19Merge tag 'for-linus-5.3a-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tipLinus Torvalds1-1/+0
Pull xen updates from Juergen Gross: "Fixes and features: - A series to introduce a common command line parameter for disabling paravirtual extensions when running as a guest in virtualized environment - A fix for int3 handling in Xen pv guests - Removal of the Xen-specific tmem driver as support of tmem in Xen has been dropped (and it was experimental only) - A security fix for running as Xen dom0 (XSA-300) - A fix for IRQ handling when offlining cpus in Xen guests - Some small cleanups" * tag 'for-linus-5.3a-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: let alloc_xenballooned_pages() fail if not enough memory free xen/pv: Fix a boot up hang revealed by int3 self test x86/xen: Add "nopv" support for HVM guest x86/paravirt: Remove const mark from x86_hyper_xen_hvm variable xen: Map "xen_nopv" parameter to "nopv" and mark it obsolete x86: Add "nopv" parameter to disable PV extensions x86/xen: Mark xen_hvm_need_lapic() and xen_x2apic_para_available() as __init xen: remove tmem driver Revert "x86/paravirt: Set up the virt_spin_lock_key after static keys get initialized" xen/events: fix binding user event channels to cpus
2019-07-18proc/sysctl: add shared variables for range checkMatteo Croce1-5/+2
In the sysctl code the proc_dointvec_minmax() function is often used to validate the user supplied value between an allowed range. This function uses the extra1 and extra2 members from struct ctl_table as minimum and maximum allowed value. On sysctl handler declaration, in every source file there are some readonly variables containing just an integer which address is assigned to the extra1 and extra2 members, so the sysctl range is enforced. The special values 0, 1 and INT_MAX are very often used as range boundary, leading duplication of variables like zero=0, one=1, int_max=INT_MAX in different source files: $ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l 248 Add a const int array containing the most commonly used values, some macros to refer more easily to the correct array member, and use them instead of creating a local one for every object file. This is the bloat-o-meter output comparing the old and new binary compiled with the default Fedora config: # scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164) Data old new delta sysctl_vals - 12 +12 __kstrtab_sysctl_vals - 12 +12 max 14 10 -4 int_max 16 - -16 one 68 - -68 zero 128 28 -100 Total: Before=20583249, After=20583085, chg -0.00% [mcroce@redhat.com: tipc: remove two unused variables] Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com [akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c] [arnd@arndb.de: proc/sysctl: make firmware loader table conditional] Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de [akpm@linux-foundation.org: fix fs/eventpoll.c] Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.com Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Kees Cook <keescook@chromium.org> Reviewed-by: Aaron Tomlin <atomlin@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-18x86/entry: Fix thunk function ELF sizesJosh Poimboeuf1-3/+2
Fix the following warnings: arch/x86/entry/thunk_64.o: warning: objtool: trace_hardirqs_on_thunk() is missing an ELF size annotation arch/x86/entry/thunk_64.o: warning: objtool: trace_hardirqs_off_thunk() is missing an ELF size annotation arch/x86/entry/thunk_64.o: warning: objtool: lockdep_sys_exit_thunk() is missing an ELF size annotation Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/89c97adc9f6cc44a0f5d03cde6d0357662938909.1563413318.git.jpoimboe@redhat.com
2019-07-17x86/mm, tracing: Fix CR2 corruptionPeter Zijlstra2-20/+40
Despite the current efforts to read CR2 before tracing happens there still exist a number of possible holes: idtentry page_fault do_page_fault has_error_code=1 call error_entry TRACE_IRQS_OFF call trace_hardirqs_off* #PF // modifies CR2 CALL_enter_from_user_mode __context_tracking_exit() trace_user_exit(0) #PF // modifies CR2 call do_page_fault address = read_cr2(); /* whoopsie */ And similar for i386. Fix it by pulling the CR2 read into the entry code, before any of that stuff gets a chance to run and ruin things. Reported-by: He Zhe <zhe.he@windriver.com> Reported-by: Eiichi Tsukata <devel@etsukata.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Andy Lutomirski <luto@kernel.org> Cc: bp@alien8.de Cc: rostedt@goodmis.org Cc: torvalds@linux-foundation.org Cc: hpa@zytor.com Cc: dave.hansen@linux.intel.com Cc: jgross@suse.com Cc: joel@joelfernandes.org Link: https://lkml.kernel.org/r/20190711114336.116812491@infradead.org Debugged-by: Steven Rostedt <rostedt@goodmis.org>
2019-07-17x86/entry/64: Update comments and sanity tests for create_gapPeter Zijlstra1-6/+11
Commit 2700fefdb2d9 ("x86_64: Add gap to int3 to allow for call emulation") forgot to update the comment, do so now. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: bp@alien8.de Cc: torvalds@linux-foundation.org Cc: hpa@zytor.com Cc: dave.hansen@linux.intel.com Cc: jgross@suse.com Cc: zhe.he@windriver.com Cc: joel@joelfernandes.org Cc: devel@etsukata.com Link: https://lkml.kernel.org/r/20190711114336.059780563@infradead.org
2019-07-17x86/entry/64: Simplify idtentry a littlePeter Zijlstra1-54/+48
There's a bunch of duplication in idtentry, namely the .Lfrom_usermode_switch_stack is a paranoid=0 copy of the normal flow. Make this explicit by creating a idtentry_part helper macro. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: bp@alien8.de Cc: torvalds@linux-foundation.org Cc: hpa@zytor.com Cc: dave.hansen@linux.intel.com Cc: jgross@suse.com Cc: zhe.he@windriver.com Cc: joel@joelfernandes.org Cc: devel@etsukata.com Link: https://lkml.kernel.org/r/20190711114336.002429503@infradead.org
2019-07-17x86/entry/32: Simplify common_exceptionPeter Zijlstra1-23/+13
Adding one more option to SAVE_ALL can be used in common_exception to simplify things. This also saves duplication later where page_fault will no longer use common_exception. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Andy Lutomirski <luto@kernel.org> Cc: bp@alien8.de Cc: torvalds@linux-foundation.org Cc: hpa@zytor.com Cc: dave.hansen@linux.intel.com Cc: jgross@suse.com Cc: zhe.he@windriver.com Cc: joel@joelfernandes.org Cc: devel@etsukata.com Link: https://lkml.kernel.org/r/20190711114335.945136187@infradead.org
2019-07-17x86/paravirt: Make read_cr2() CALLEE_SAVEPeter Zijlstra1-0/+6
The one paravirt read_cr2() implementation (Xen) is actually quite trivial and doesn't need to clobber anything other than the return register. Making read_cr2() CALLEE_SAVE avoids all the PUSH/POP nonsense and allows more convenient use from assembly. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: bp@alien8.de Cc: rostedt@goodmis.org Cc: luto@kernel.org Cc: torvalds@linux-foundation.org Cc: hpa@zytor.com Cc: dave.hansen@linux.intel.com Cc: zhe.he@windriver.com Cc: joel@joelfernandes.org Cc: devel@etsukata.com Link: https://lkml.kernel.org/r/20190711114335.887392493@infradead.org
2019-07-17kbuild: add --hash-style= and --build-id unconditionallyMasahiro Yamada1-3/+2
As commit 1e0221374e30 ("mips: vdso: drop unnecessary cc-ldoption") explained, these flags are supported by the minimal required version of binutils. They are supported by ld.lld too. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Nathan Chancellor <natechancellor@gmail.com>
2019-07-17x86/entry/64: Use JMP instead of JMPQJosh Poimboeuf1-1/+1
Somehow the swapgs mitigation entry code patch ended up with a JMPQ instruction instead of JMP, where only the short jump is needed. Some assembler versions apparently fail to optimize JMPQ into a two-byte JMP when possible, instead always using a 7-byte JMP with relocation. For some reason that makes the entry code explode with a #GP during boot. Change it back to "JMP" as originally intended. Fixes: 18ec54fdd6d1 ("x86/speculation: Prepare entry code for Spectre v1 swapgs mitigations") Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2019-07-17xen/pv: Fix a boot up hang revealed by int3 self testZhenzhong Duan1-1/+0
Commit 7457c0da024b ("x86/alternatives: Add int3_emulate_call() selftest") is used to ensure there is a gap setup in int3 exception stack which could be used for inserting call return address. This gap is missed in XEN PV int3 exception entry path, then below panic triggered: [ 0.772876] general protection fault: 0000 [#1] SMP NOPTI [ 0.772886] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.2.0+ #11 [ 0.772893] RIP: e030:int3_magic+0x0/0x7 [ 0.772905] RSP: 3507:ffffffff82203e98 EFLAGS: 00000246 [ 0.773334] Call Trace: [ 0.773334] alternative_instructions+0x3d/0x12e [ 0.773334] check_bugs+0x7c9/0x887 [ 0.773334] ? __get_locked_pte+0x178/0x1f0 [ 0.773334] start_kernel+0x4ff/0x535 [ 0.773334] ? set_init_arg+0x55/0x55 [ 0.773334] xen_start_kernel+0x571/0x57a For 64bit PV guests, Xen's ABI enters the kernel with using SYSRET, with %rcx/%r11 on the stack. To convert back to "normal" looking exceptions, the xen thunks do 'xen_*: pop %rcx; pop %r11; jmp *'. E.g. Extracting 'xen_pv_trap xenint3' we have: xen_xenint3: pop %rcx; pop %r11; jmp xenint3 As xenint3 and int3 entry code are same except xenint3 doesn't generate a gap, we can fix it by using int3 and drop useless xenint3. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-07-12x86/vdso: Fix flip/flop vdso build bugNaohiro Aota1-6/+6
Two consecutive "make" on an already compiled kernel tree will show different behavior: $ make CALL scripts/checksyscalls.sh CALL scripts/atomic/check-atomics.sh DESCEND objtool CHK include/generated/compile.h VDSOCHK arch/x86/entry/vdso/vdso64.so.dbg VDSOCHK arch/x86/entry/vdso/vdso32.so.dbg Kernel: arch/x86/boot/bzImage is ready (#3) Building modules, stage 2. MODPOST 12 modules $ make make CALL scripts/checksyscalls.sh CALL scripts/atomic/check-atomics.sh DESCEND objtool CHK include/generated/compile.h VDSO arch/x86/entry/vdso/vdso64.so.dbg OBJCOPY arch/x86/entry/vdso/vdso64.so VDSO2C arch/x86/entry/vdso/vdso-image-64.c CC arch/x86/entry/vdso/vdso-image-64.o VDSO arch/x86/entry/vdso/vdso32.so.dbg OBJCOPY arch/x86/entry/vdso/vdso32.so VDSO2C arch/x86/entry/vdso/vdso-image-32.c CC arch/x86/entry/vdso/vdso-image-32.o AR arch/x86/entry/vdso/built-in.a AR arch/x86/entry/built-in.a AR arch/x86/built-in.a GEN .version CHK include/generated/compile.h UPD include/generated/compile.h CC init/version.o AR init/built-in.a LD vmlinux.o <snip> This is causing "LD vmlinux" once every two times even without any modifications. This is the same bug fixed in commit 92a4728608a8 ("x86/boot: Fix if_changed build flip/flop bug"). Two "if_changed" cannot be used in one target. Fix this merging two commands into one function. Fixes: 7ac870747988 ("x86/vdso: Switch to generic vDSO implementation") Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com> Link: https://lkml.kernel.org/r/20190712101556.17833-1-naohiro.aota@wdc.com
2019-07-11Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-1/+1
Pull x86 fixes from Thomas Gleixner: "A collection of assorted fixes: - Fix for the pinned cr0/4 fallout which escaped all testing efforts because the kvm-intel module was never loaded when the kernel was compiled with CONFIG_PARAVIRT=n. The cr0/4 accessors are moved out of line and static key is now solely used in the core code and therefore can stay in the RO after init section. So the kvm-intel and other modules do not longer reference the (read only) static key which the module loader tried to update. - Prevent an infinite loop in arch_stack_walk_user() by breaking out of the loop once the return address is detected to be 0. - Prevent the int3_emulate_call() selftest from corrupting the stack when KASAN is enabled. KASASN clobbers more registers than covered by the emulated call implementation. Convert the int3_magic() selftest to a ASM function so the compiler cannot KASANify it. - Unbreak the build with old GCC versions and with the Gold linker by reverting the 'Move of _etext to the actual end of .text'. In both cases the build fails with 'Invalid absolute R_X86_64_32S relocation: _etext' - Initialize the context lock for init_mm, which was never an issue until the alternatives code started to use a temporary mm for patching. - Fix a build warning vs. the LOWMEM_PAGES constant where clang complains rightfully about a signed integer overflow in the shift operation by converting the operand to an ULL. - Adjust the misnamed ENDPROC() of common_spurious in the 32bit entry code" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/stacktrace: Prevent infinite loop in arch_stack_walk_user() x86/asm: Move native_write_cr0/4() out of line x86/pgtable/32: Fix LOWMEM_PAGES constant x86/alternatives: Fix int3_emulate_call() selftest stack corruption x86/entry/32: Fix ENDPROC of common_spurious Revert "x86/build: Move _etext to actual end of .text" x86/ldt: Initialize the context lock for init_mm
2019-07-11Merge tag 'clone3-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linuxLinus Torvalds2-0/+2
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
2019-07-10Merge tag 'pidfd-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linuxLinus Torvalds2-0/+2
Pull pidfd updates from Christian Brauner: "This adds two main features. - First, it adds polling support for pidfds. This allows process managers to know when a (non-parent) process dies in a race-free way. The notification mechanism used follows the same logic that is currently used when the parent of a task is notified of a child's death. With this patchset it is possible to put pidfds in an {e}poll loop and get reliable notifications for process (i.e. thread-group) exit. - The second feature compliments the first one by making it possible to retrieve pollable pidfds for processes that were not created using CLONE_PIDFD. A lot of processes get created with traditional PID-based calls such as fork() or clone() (without CLONE_PIDFD). For these processes a caller can currently not create a pollable pidfd. This is a problem for Android's low memory killer (LMK) and service managers such as systemd. Both patchsets are accompanied by selftests. It's perhaps worth noting that the work done so far and the work done in this branch for pidfd_open() and polling support do already see some adoption: - Android is in the process of backporting this work to all their LTS kernels [1] - Service managers make use of pidfd_send_signal but will need to wait until we enable waiting on pidfds for full adoption. - And projects I maintain make use of both pidfd_send_signal and CLONE_PIDFD [2] and will use polling support and pidfd_open() too" [1] https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.9+backport%22 https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.14+backport%22 https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.19+backport%22 [2] https://github.com/lxc/lxc/blob/aab6e3eb73c343231cdde775db938994fc6f2803/src/lxc/start.c#L1753 * tag 'pidfd-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: tests: add pidfd_open() tests arch: wire-up pidfd_open() pid: add pidfd_open() pidfd: add polling selftests pidfd: add polling support
2019-07-09Merge tag 'docs-5.3' of git://git.lwn.net/linuxLinus Torvalds1-1/+1
Pull Documentation updates from Jonathan Corbet: "It's been a relatively busy cycle for docs: - A fair pile of RST conversions, many from Mauro. These create more than the usual number of simple but annoying merge conflicts with other trees, unfortunately. He has a lot more of these waiting on the wings that, I think, will go to you directly later on. - A new document on how to use merges and rebases in kernel repos, and one on Spectre vulnerabilities. - Various improvements to the build system, including automatic markup of function() references because some people, for reasons I will never understand, were of the opinion that :c:func:``function()`` is unattractive and not fun to type. - We now recommend using sphinx 1.7, but still support back to 1.4. - Lots of smaller improvements, warning fixes, typo fixes, etc" * tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits) docs: automarkup.py: ignore exceptions when seeking for xrefs docs: Move binderfs to admin-guide Disable Sphinx SmartyPants in HTML output doc: RCU callback locks need only _bh, not necessarily _irq docs: format kernel-parameters -- as code Doc : doc-guide : Fix a typo platform: x86: get rid of a non-existent document Add the RCU docs to the core-api manual Documentation: RCU: Add TOC tree hooks Documentation: RCU: Rename txt files to rst Documentation: RCU: Convert RCU UP systems to reST Documentation: RCU: Convert RCU linked list to reST Documentation: RCU: Convert RCU basic concepts to reST docs: filesystems: Remove uneeded .rst extension on toctables scripts/sphinx-pre-install: fix out-of-tree build docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/ Documentation: PGP: update for newer HW devices Documentation: Add section about CPU vulnerabilities for Spectre Documentation: platform: Delete x86-laptop-drivers.txt docs: Note that :c:func: should no longer be used ...
2019-07-09x86/entry/32: Fix ENDPROC of common_spuriousJiri Slaby1-1/+1
common_spurious is currently ENDed erroneously. common_interrupt is used in its ENDPROC. So fix this mistake. Found by my asm macros rewrite patchset. Fixes: f8a8fe61fec8 ("x86/irq: Seperate unused system vectors from spurious entry again") Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190709063402.19847-1-jslaby@suse.cz
2019-07-09x86/speculation: Prepare entry code for Spectre v1 swapgs mitigationsJosh Poimboeuf2-3/+35
Spectre v1 isn't only about array bounds checks. It can affect any conditional checks. The kernel entry code interrupt, exception, and NMI handlers all have conditional swapgs checks. Those may be problematic in the context of Spectre v1, as kernel code can speculatively run with a user GS. For example: if (coming from user space) swapgs mov %gs:<percpu_offset>, %reg mov (%reg), %reg1 When coming from user space, the CPU can speculatively skip the swapgs, and then do a speculative percpu load using the user GS value. So the user can speculatively force a read of any kernel value. If a gadget exists which uses the percpu value as an address in another load/store, then the contents of the kernel value may become visible via an L1 side channel attack. A similar attack exists when coming from kernel space. The CPU can speculatively do the swapgs, causing the user GS to get used for the rest of the speculative window. The mitigation is similar to a traditional Spectre v1 mitigation, except: a) index masking isn't possible; because the index (percpu offset) isn't user-controlled; and b) an lfence is needed in both the "from user" swapgs path and the "from kernel" non-swapgs path (because of the two attacks described above). The user entry swapgs paths already have SWITCH_TO_KERNEL_CR3, which has a CR3 write when PTI is enabled. Since CR3 writes are serializing, the lfences can be skipped in those cases. On the other hand, the kernel entry swapgs paths don't depend on PTI. To avoid unnecessary lfences for the user entry case, create two separate features for alternative patching: X86_FEATURE_FENCE_SWAPGS_USER X86_FEATURE_FENCE_SWAPGS_KERNEL Use these features in entry code to patch in lfences where needed. The features aren't enabled yet, so there's no functional change. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Dave Hansen <dave.hansen@intel.com>
2019-07-08Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespaceLinus Torvalds1-2/+2
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 ...
2019-07-08Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+5
Pull x86 platform updayes from Ingo Molnar: "Most of the commits add ACRN hypervisor guest support, plus two cleanups" * 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/jailhouse: Mark jailhouse_x2apic_available() as __init x86/platform/geode: Drop <linux/gpio.h> includes x86/acrn: Use HYPERVISOR_CALLBACK_VECTOR for ACRN guest upcall vector x86: Add support for Linux guests on an ACRN hypervisor x86/Kconfig: Add new X86_HV_CALLBACK_VECTOR config symbol
2019-07-08Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds2-55/+105
Pull x86 asm updates from Ingo Molnar: "Most of the changes relate to Peter Zijlstra's cleanup of ptregs handling, in particular the i386 part is now much simplified and standardized - no more partial ptregs stack frames via the esp/ss oddity. This simplifies ftrace, kprobes, the unwinder, ptrace, kdump and kgdb. There's also a CR4 hardening enhancements by Kees Cook, to make the generic platform functions such as native_write_cr4() less useful as ROP gadgets that disable SMEP/SMAP. Also protect the WP bit of CR0 against similar attacks. The rest is smaller cleanups/fixes" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/alternatives: Add int3_emulate_call() selftest x86/stackframe/32: Allow int3_emulate_push() x86/stackframe/32: Provide consistent pt_regs x86/stackframe, x86/ftrace: Add pt_regs frame annotations x86/stackframe, x86/kprobes: Fix frame pointer annotations x86/stackframe: Move ENCODE_FRAME_POINTER to asm/frame.h x86/entry/32: Clean up return from interrupt preemption path x86/asm: Pin sensitive CR0 bits x86/asm: Pin sensitive CR4 bits Documentation/x86: Fix path to entry_32.S x86/asm: Remove unused TASK_TI_flags from asm-offsets.c
2019-07-08Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+6
Pull x86 CPU feature updates from Thomas Gleixner: "Updates for x86 CPU features: - Support for UMWAIT/UMONITOR, which allows to use MWAIT and MONITOR instructions in user space to save power e.g. in HPC workloads which spin wait on synchronization points. The maximum time a MWAIT can halt in userspace is controlled by the kernel and can be adjusted by the sysadmin. - Speed up the MTRR handling code on CPUs which support cache self-snooping correctly. On those CPUs the wbinvd() invocations can be omitted which speeds up the MTRR setup by a factor of 50. - Support for the new x86 vendor Zhaoxin who develops processors based on the VIA Centaur technology. - Prevent 'cat /proc/cpuinfo' from affecting isolated NOHZ_FULL CPUs by sending IPIs to retrieve the CPU frequency and use the cached values instead. - The addition and late revert of the FSGSBASE support. The revert was required as it turned out that the code still has hard to diagnose issues. Yet another engineering trainwreck... - Small fixes, cleanups, improvements and the usual new Intel CPU family/model addons" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits) x86/fsgsbase: Revert FSGSBASE support selftests/x86/fsgsbase: Fix some test case bugs x86/entry/64: Fix and clean up paranoid_exit x86/entry/64: Don't compile ignore_sysret if 32-bit emulation is enabled selftests/x86: Test SYSCALL and SYSENTER manually with TF set x86/mtrr: Skip cache flushes on CPUs with cache self-snooping x86/cpu/intel: Clear cache self-snoop capability in CPUs with known errata Documentation/ABI: Document umwait control sysfs interfaces x86/umwait: Add sysfs interface to control umwait maximum time x86/umwait: Add sysfs interface to control umwait C0.2 state x86/umwait: Initialize umwait control values x86/cpufeatures: Enumerate user wait instructions x86/cpu: Disable frequency requests via aperfmperf IPI for nohz_full CPUs x86/acpi/cstate: Add Zhaoxin processors support for cache flush policy in C3 ACPI, x86: Add Zhaoxin processors support for NONSTOP TSC x86/cpu: Create Zhaoxin processors architecture support file x86/cpu: Split Tremont based Atoms from the rest Documentation/x86/64: Add documentation for GS/FS addressing mode x86/elf: Enumerate kernel FSGSBASE capability in AT_HWCAP2 x86/cpu: Enable FSGSBASE on 64bit by default and add a chicken bit ...
2019-07-08Merge branch 'x86-entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-4/+33
Pull x86 vsyscall updates from Thomas Gleixner: "Further hardening of the legacy vsyscall by providing support for execute only mode and switching the default to it. This prevents a certain class of attacks which rely on the vsyscall page being accessible at a fixed address in the canonical kernel address space" * 'x86-entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: selftests/x86: Add a test for process_vm_readv() on the vsyscall page x86/vsyscall: Add __ro_after_init to global variables x86/vsyscall: Change the default vsyscall mode to xonly selftests/x86/vsyscall: Verify that vsyscall=none blocks execution x86/vsyscall: Document odd SIGSEGV error code for vsyscalls x86/vsyscall: Show something useful on a read fault x86/vsyscall: Add a new vsyscall=xonly mode Documentation/admin: Remove the vsyscall=native documentation
2019-07-08Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds2-4/+50
Pull x96 apic updates from Thomas Gleixner: "Updates for the x86 APIC interrupt handling and APIC timer: - Fix a long standing issue with spurious interrupts which was caused by the big vector management rework a few years ago. Robert Hodaszi provided finally enough debug data and an excellent initial failure analysis which allowed to understand the underlying issues. This contains a change to the core interrupt management code which is required to handle this correctly for the APIC/IO_APIC. The core changes are NOOPs for most architectures except ARM64. ARM64 is not impacted by the change as confirmed by Marc Zyngier. - Newer systems allow to disable the PIT clock for power saving causing panic in the timer interrupt delivery check of the IO/APIC when the HPET timer is not enabled either. While the clock could be turned on this would cause an endless whack a mole game to chase the proper register in each affected chipset. These systems provide the relevant frequencies for TSC, CPU and the local APIC timer via CPUID and/or MSRs, which allows to avoid the PIT/HPET based calibration. As the calibration code is the only usage of the legacy timers on modern systems and is skipped anyway when the frequencies are known already, there is no point in setting up the PIT and actually checking for the interrupt delivery via IO/APIC. To achieve this on a wide variety of platforms, the CPUID/MSR based frequency readout has been made more robust, which also allowed to remove quite some workarounds which turned out to be not longer required. Thanks to Daniel Drake for analysis, patches and verification" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/irq: Seperate unused system vectors from spurious entry again x86/irq: Handle spurious interrupt after shutdown gracefully x86/ioapic: Implement irq_get_irqchip_state() callback genirq: Add optional hardware synchronization for shutdown genirq: Fix misleading synchronize_irq() documentation genirq: Delay deactivation in free_irq() x86/timer: Skip PIT initialization on modern chipsets x86/apic: Use non-atomic operations when possible x86/apic: Make apic_bsp_setup() static x86/tsc: Set LAPIC timer period to crystal clock frequency x86/apic: Rename 'lapic_timer_frequency' to 'lapic_timer_period' x86/tsc: Use CPUID.0x16 to calculate missing crystal frequency
2019-07-08Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds8-297/+60
Pull timer updates from Thomas Gleixner: "The timer and timekeeping departement delivers: Core: - The consolidation of the VDSO code into a generic library including the conversion of x86 and ARM64. Conversion of ARM and MIPS are en route through the relevant maintainer trees and should end up in 5.4. This gets rid of the unnecessary different copies of the same code and brings all architectures on the same level of VDSO functionality. - Make the NTP user space interface more robust by restricting the TAI offset to prevent undefined behaviour. Includes a selftest. - Validate user input in the compat settimeofday() syscall to catch invalid values which would be turned into valid values by a multiplication overflow - Consolidate the time accessors - Small fixes, improvements and cleanups all over the place Drivers: - Support for the NXP system counter, TI davinci timer - Move the Microsoft HyperV clocksource/events code into the drivers/clocksource directory so it can be shared between x86 and ARM64. - Overhaul of the Tegra driver - Delay timer support for IXP4xx - Small fixes, improvements and cleanups as usual" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits) time: Validate user input in compat_settimeofday() timer: Document TIMER_PINNED clocksource/drivers: Continue making Hyper-V clocksource ISA agnostic clocksource/drivers: Make Hyper-V clocksource ISA agnostic MAINTAINERS: Fix Andy's surname and the directory entries of VDSO hrtimer: Use a bullet for the returns bullet list arm64: vdso: Fix compilation with clang older than 8 arm64: compat: Fix __arch_get_hw_counter() implementation arm64: Fix __arch_get_hw_counter() implementation lib/vdso: Make delta calculation work correctly MAINTAINERS: Add entry for the generic VDSO library arm64: compat: No need for pre-ARMv7 barriers on an ARMv8 system arm64: vdso: Remove unnecessary asm-offsets.c definitions vdso: Remove superfluous #ifdef __KERNEL__ in vdso/datapage.h clocksource/drivers/davinci: Add support for clocksource clocksource/drivers/davinci: Add support for clockevents clocksource/drivers/tegra: Set up maximum-ticks limit properly clocksource/drivers/tegra: Cycles can't be 0 clocksource/drivers/tegra: Restore base address before cleanup clocksource/drivers/tegra: Add verbose definition for 1MHz constant ...
2019-07-08Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds1-11/+6
Pull arm64 updates from Catalin Marinas: - arm64 support for syscall emulation via PTRACE_SYSEMU{,_SINGLESTEP} - Wire up VM_FLUSH_RESET_PERMS for arm64, allowing the core code to manage the permissions of executable vmalloc regions more strictly - Slight performance improvement by keeping softirqs enabled while touching the FPSIMD/SVE state (kernel_neon_begin/end) - Expose a couple of ARMv8.5 features to user (HWCAP): CondM (new XAFLAG and AXFLAG instructions for floating point comparison flags manipulation) and FRINT (rounding floating point numbers to integers) - Re-instate ARM64_PSEUDO_NMI support which was previously marked as BROKEN due to some bugs (now fixed) - Improve parking of stopped CPUs and implement an arm64-specific panic_smp_self_stop() to avoid warning on not being able to stop secondary CPUs during panic - perf: enable the ARM Statistical Profiling Extensions (SPE) on ACPI platforms - perf: DDR performance monitor support for iMX8QXP - cache_line_size() can now be set from DT or ACPI/PPTT if provided to cope with a system cache info not exposed via the CPUID registers - Avoid warning on hardware cache line size greater than ARCH_DMA_MINALIGN if the system is fully coherent - arm64 do_page_fault() and hugetlb cleanups - Refactor set_pte_at() to avoid redundant READ_ONCE(*ptep) - Ignore ACPI 5.1 FADTs reported as 5.0 (infer from the 'arm_boot_flags' introduced in 5.1) - CONFIG_RANDOMIZE_BASE now enabled in defconfig - Allow the selection of ARM64_MODULE_PLTS, currently only done via RANDOMIZE_BASE (and an erratum workaround), allowing modules to spill over into the vmalloc area - Make ZONE_DMA32 configurable * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (54 commits) perf: arm_spe: Enable ACPI/Platform automatic module loading arm_pmu: acpi: spe: Add initial MADT/SPE probing ACPI/PPTT: Add function to return ACPI 6.3 Identical tokens ACPI/PPTT: Modify node flag detection to find last IDENTICAL x86/entry: Simplify _TIF_SYSCALL_EMU handling arm64: rename dump_instr as dump_kernel_instr arm64/mm: Drop [PTE|PMD]_TYPE_FAULT arm64: Implement panic_smp_self_stop() arm64: Improve parking of stopped CPUs arm64: Expose FRINT capabilities to userspace arm64: Expose ARMv8.5 CondM capability to userspace arm64: defconfig: enable CONFIG_RANDOMIZE_BASE arm64: ARM64_MODULES_PLTS must depend on MODULES arm64: bpf: do not allocate executable memory arm64/kprobes: set VM_FLUSH_RESET_PERMS on kprobe instruction pages arm64/mm: wire up CONFIG_ARCH_HAS_SET_DIRECT_MAP arm64: module: create module allocations without exec permissions arm64: Allow user selection of ARM64_MODULE_PLTS acpi/arm64: ignore 5.1 FADTs that are reported as 5.0 arm64: Allow selecting Pseudo-NMI again ...
2019-07-03x86/fsgsbase: Revert FSGSBASE supportThomas Gleixner2-143/+29
The FSGSBASE series turned out to have serious bugs and there is still an open issue which is not fully understood yet. The confidence in those changes has become close to zero especially as the test cases which have been shipped with that series were obviously never run before sending the final series out to LKML. ./fsgsbase_64 >/dev/null Segmentation fault As the merge window is close, the only sane decision is to revert FSGSBASE support. The revert is necessary as this branch has been merged into perf/core already and rebasing all of that a few days before the merge window is not the most brilliant idea. I could definitely slap myself for not noticing the test case fail when merging that series, but TBH my expectations weren't that low back then. Won't happen again. Revert the following commits: 539bca535dec ("x86/entry/64: Fix and clean up paranoid_exit") 2c7b5ac5d5a9 ("Documentation/x86/64: Add documentation for GS/FS addressing mode") f987c955c745 ("x86/elf: Enumerate kernel FSGSBASE capability in AT_HWCAP2") 2032f1f96ee0 ("x86/cpu: Enable FSGSBASE on 64bit by default and add a chicken bit") 5bf0cab60ee2 ("x86/entry/64: Document GSBASE handling in the paranoid path") 708078f65721 ("x86/entry/64: Handle FSGSBASE enabled paranoid entry/exit") 79e1932fa3ce ("x86/entry/64: Introduce the FIND_PERCPU_BASE macro") 1d07316b1363 ("x86/entry/64: Switch CR3 before SWAPGS in paranoid entry") f60a83df4593 ("x86/process/64: Use FSGSBASE instructions on thread copy and ptrace") 1ab5f3f7fe3d ("x86/process/64: Use FSBSBASE in switch_to() if available") a86b4625138d ("x86/fsgsbase/64: Enable FSGSBASE instructions in helper functions") 8b71340d702e ("x86/fsgsbase/64: Add intrinsics for FSGSBASE instructions") b64ed19b93c3 ("x86/cpu: Add 'unsafe_fsgsbase' to enable CR4.FSGSBASE") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Chang S. Bae <chang.seok.bae@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com>
2019-07-03clocksource/drivers: Continue making Hyper-V clocksource ISA agnosticMichael Kelley1-1/+1
Continue consolidating Hyper-V clock and timer code into an ISA independent Hyper-V clocksource driver. Move the existing clocksource code under drivers/hv and arch/x86 to the new clocksource driver while separating out the ISA dependencies. Update Hyper-V initialization to call initialization and cleanup routines since the Hyper-V synthetic clock is not independently enumerated in ACPI. Update Hyper-V clocksource users in KVM and VDSO to get definitions from the new include file. No behavior is changed and no new functionality is added. Suggested-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: "bp@alien8.de" <bp@alien8.de> Cc: "will.deacon@arm.com" <will.deacon@arm.com> Cc: "catalin.marinas@arm.com" <catalin.marinas@arm.com> Cc: "mark.rutland@arm.com" <mark.rutland@arm.com> Cc: "linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org> Cc: "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org> Cc: "linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org> Cc: "olaf@aepfle.de" <olaf@aepfle.de> Cc: "apw@canonical.com" <apw@canonical.com> Cc: "jasowang@redhat.com" <jasowang@redhat.com> Cc: "marcelo.cerri@canonical.com" <marcelo.cerri@canonical.com> Cc: Sunil Muthuswamy <sunilmut@microsoft.com> Cc: KY Srinivasan <kys@microsoft.com> Cc: "sashal@kernel.org" <sashal@kernel.org> Cc: "vincenzo.frascino@arm.com" <vincenzo.frascino@arm.com> Cc: "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org> Cc: "linux-mips@vger.kernel.org" <linux-mips@vger.kernel.org> Cc: "linux-kselftest@vger.kernel.org" <linux-kselftest@vger.kernel.org> Cc: "arnd@arndb.de" <arnd@arndb.de> Cc: "linux@armlinux.org.uk" <linux@armlinux.org.uk> Cc: "ralf@linux-mips.org" <ralf@linux-mips.org> Cc: "paul.burton@mips.com" <paul.burton@mips.com> Cc: "daniel.lezcano@linaro.org" <daniel.lezcano@linaro.org> Cc: "salyzyn@android.com" <salyzyn@android.com> Cc: "pcc@google.com" <pcc@google.com> Cc: "shuah@kernel.org" <shuah@kernel.org> Cc: "0x7f454c46@gmail.com" <0x7f454c46@gmail.com> Cc: "linux@rasmusvillemoes.dk" <linux@rasmusvillemoes.dk> Cc: "huw@codeweavers.com" <huw@codeweavers.com> Cc: "sfr@canb.auug.org.au" <sfr@canb.auug.org.au> Cc: "pbonzini@redhat.com" <pbonzini@redhat.com> Cc: "rkrcmar@redhat.com" <rkrcmar@redhat.com> Cc: "kvm@vger.kernel.org" <kvm@vger.kernel.org> Link: https://lkml.kernel.org/r/1561955054-1838-3-git-send-email-mikelley@microsoft.com
2019-07-03x86/irq: Seperate unused system vectors from spurious entry againThomas Gleixner2-4/+50
Quite some time ago the interrupt entry stubs for unused vectors in the system vector range got removed and directly mapped to the spurious interrupt vector entry point. Sounds reasonable, but it's subtly broken. The spurious interrupt vector entry point pushes vector number 0xFF on the stack which makes the whole logic in __smp_spurious_interrupt() pointless. As a consequence any spurious interrupt which comes from a vector != 0xFF is treated as a real spurious interrupt (vector 0xFF) and not acknowledged. That subsequently stalls all interrupt vectors of equal and lower priority, which brings the system to a grinding halt. This can happen because even on 64-bit the system vector space is not guaranteed to be fully populated. A full compile time handling of the unused vectors is not possible because quite some of them are conditonally populated at runtime. Bring the entry stubs back, which wastes 160 bytes if all stubs are unused, but gains the proper handling back. There is no point to selectively spare some of the stubs which are known at compile time as the required code in the IDT management would be way larger and convoluted. Do not route the spurious entries through common_interrupt and do_IRQ() as the original code did. Route it to smp_spurious_interrupt() which evaluates the vector number and acts accordingly now that the real vector numbers are handed in. Fixup the pr_warn so the actual spurious vector (0xff) is clearly distiguished from the other vectors and also note for the vectored case whether it was pending in the ISR or not. "Spurious APIC interrupt (vector 0xFF) on CPU#0, should never happen." "Spurious interrupt vector 0xed on CPU#1. Acked." "Spurious interrupt vector 0xee on CPU#1. Not pending!." Fixes: 2414e021ac8d ("x86: Avoid building unused IRQ entry stubs") Reported-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Jan Beulich <jbeulich@suse.com> Link: https://lkml.kernel.org/r/20190628111440.550568228@linutronix.de
2019-07-02x86/entry/64: Fix and clean up paranoid_exitAndy Lutomirski1-16/+17
paranoid_exit needs to restore CR3 before GSBASE. Doing it in the opposite order crashes if the exception came from a context with user GSBASE and user CR3 -- RESTORE_CR3 cannot resture user CR3 if run with user GSBASE. This results in infinitely recursing exceptions if user code does SYSENTER with TF set if both FSGSBASE and PTI are enabled. The old code worked if user code just set TF without SYSENTER because #DB from user mode is special cased in idtentry and paranoid_exit doesn't run. Fix it by cleaning up the spaghetti code. All that paranoid_exit needs to do is to disable IRQs, handle IRQ tracing, then restore CR3, and restore GSBASE. Simply do those actions in that order. Fixes: 708078f65721 ("x86/entry/64: Handle FSGSBASE enabled paranoid entry/exit") Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Link: https://lkml.kernel.org/r/59725ceb08977359489fbed979716949ad45f616.1562035429.git.luto@kernel.org
2019-07-02x86/entry/64: Don't compile ignore_sysret if 32-bit emulation is enabledAndy Lutomirski1-0/+6
It's only used if !CONFIG_IA32_EMULATION, so disable it in normal configs. This will save a few bytes of text and reduce confusion. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "BaeChang Seok" <chang.seok.bae@intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Bae, Chang Seok" <chang.seok.bae@intel.com> Link: https://lkml.kernel.org/r/0f7dafa72fe7194689de5ee8cfe5d83509fabcf5.1562035429.git.luto@kernel.org
2019-06-28arch: wire-up pidfd_open()Christian Brauner2-0/+2
This wires up the pidfd_open() syscall into all arches at once. Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: David Howells <dhowells@redhat.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jann Horn <jannh@google.com> Cc: Andy Lutomirsky <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-api@vger.kernel.org Cc: linux-alpha@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-ia64@vger.kernel.org Cc: linux-m68k@lists.linux-m68k.org Cc: linux-mips@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-arch@vger.kernel.org Cc: x86@kernel.org