summaryrefslogtreecommitdiff
path: root/arch/x86
AgeCommit message (Collapse)Author
2017-04-19Merge tag 'v4.11-rc7' into drm-nextDave Airlie
Backmerge Linux 4.11-rc7 from Linus tree, to fix some conflicts that were causing problems with the rerere cache in drm-tip.
2017-04-15Merge branch 'libnvdimm-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull nvdimm fixes from Dan Williams: "A small crop of lockdep, sleeping while atomic, and other fixes / band-aids in advance of the full-blown reworks targeting the next merge window. The largest change here is "libnvdimm: fix blk free space accounting" which deletes a pile of buggy code that better testing would have caught before merging. The next change that is borderline too big for a late rc is switching the device-dax locking from rcu to srcu, I couldn't think of a smaller way to make that fix. The __copy_user_nocache fix will have a full replacement in 4.12 to move those pmem special case considerations into the pmem driver. The "libnvdimm: band aid btt vs clear poison locking" commit admits that our error clearing support for btt went in broken, so we just disable it in 4.11 and -stable. A replacement / full fix is in the pipeline for 4.12 Some of these would have been caught earlier had DEBUG_ATOMIC_SLEEP been enabled on my development station. I wonder if we should have: config DEBUG_ATOMIC_SLEEP default PROVE_LOCKING ...since I mistakenly thought I got both with PROVE_LOCKING=y. These have received a build success notification from the 0day robot, and some have appeared in a -next release with no reported issues" * 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: x86, pmem: fix broken __copy_user_nocache cache-bypass assumptions device-dax: switch to srcu, fix rcu_read_lock() vs pte allocation libnvdimm: band aid btt vs clear poison locking libnvdimm: fix reconfig_mutex, mmap_sem, and jbd2_handle lockdep splat libnvdimm: fix blk free space accounting acpi, nfit, libnvdimm: fix interleave set cookie calculation (64-bit comparison)
2017-04-14Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A set of small fixes for x86: - fix locking in RDT to prevent memory leaks and freeing in use memory - prevent setting invalid values for vdso32_enabled which cause inconsistencies for user space resulting in application crashes. - plug a race in the vdso32 code between fork and sysctl which causes inconsistencies for user space resulting in application crashes. - make MPX signal delivery work in compat mode - make the dmesg output of traps and faults readable again" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/intel_rdt: Fix locking in rdtgroup_schemata_write() x86/debug: Fix the printk() debug output of signal_fault(), do_trap() and do_general_protection() x86/vdso: Plug race between mapping and ELF header setup x86/vdso: Ensure vdso32_enabled gets set to valid values only x86/signals: Fix lower/upper bound reporting in compat siginfo
2017-04-14Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "Two small fixes for perf: - the move to support cross arch annotation introduced per arch initialization requirements, fullfill them for s/390 (Christian Borntraeger) - add the missing initialization to the LBR entries to avoid exposing random or stale data" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86: Avoid exposing wrong/stale data in intel_pmu_lbr_read_32() perf annotate s390: Fix perf annotate error -95 (4.10 regression)
2017-04-14Merge branch 'efi-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI fixes from Thomas Gleixner: "Three fixes from EFI land: - prevent accessing a Graphic Output Device (GOP) which the kernel does not know to handle - prevent PCI reconfiguration to modify a BAR which covers the framebuffer because that's already in use through the EFI GOP interface - avoid reserving EFI runtime regions as this results in bogus memory mappings" * 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/efi: Don't try to reserve runtime regions efi/fb: Avoid reconfiguration of BAR that covers the framebuffer efi/libstub: Skip GOP with PIXEL_BLT_ONLY format
2017-04-14perf/x86: Avoid exposing wrong/stale data in intel_pmu_lbr_read_32()Peter Zijlstra
When the perf_branch_entry::{in_tx,abort,cycles} fields were added, intel_pmu_lbr_read_32() wasn't updated to initialize them. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Cc: <stable@vger.kernel.org> Fixes: 135c5612c460 ("perf/x86/intel: Support Haswell/v4 LBR format") Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-13x86/efi: Don't try to reserve runtime regionsOmar Sandoval
Reserving a runtime region results in splitting the EFI memory descriptors for the runtime region. This results in runtime region descriptors with bogus memory mappings, leading to interesting crashes like the following during a kexec: general protection fault: 0000 [#1] SMP Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.11.0-rc1 #53 Hardware name: Wiwynn Leopard-Orv2/Leopard-DDR BW, BIOS LBM05 09/30/2016 RIP: 0010:virt_efi_set_variable() ... Call Trace: efi_delete_dummy_variable() efi_enter_virtual_mode() start_kernel() ? set_init_arg() x86_64_start_reservations() x86_64_start_kernel() start_cpu() ... Kernel panic - not syncing: Fatal exception Runtime regions will not be freed and do not need to be reserved, so skip the memmap modification in this case. Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: <stable@vger.kernel.org> # v4.9+ Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Dave Young <dyoung@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Fixes: 8e80632fb23f ("efi/esrt: Use efi_mem_reserve() and avoid a kmalloc()") Link: http://lkml.kernel.org/r/20170412152719.9779-2-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-12x86, pmem: fix broken __copy_user_nocache cache-bypass assumptionsDan Williams
Before we rework the "pmem api" to stop abusing __copy_user_nocache() for memcpy_to_pmem() we need to fix cases where we may strand dirty data in the cpu cache. The problem occurs when copy_from_iter_pmem() is used for arbitrary data transfers from userspace. There is no guarantee that these transfers, performed by dax_iomap_actor(), will have aligned destinations or aligned transfer lengths. Backstop the usage __copy_user_nocache() with explicit cache management in these unaligned cases. Yes, copy_from_iter_pmem() is now too big for an inline, but addressing that is saved for a later patch that moves the entirety of the "pmem api" into the pmem driver directly. Fixes: 5de490daec8b ("pmem: add copy_from_iter_pmem() and clear_pmem()") Cc: <stable@vger.kernel.org> Cc: <x86@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-12mm: Tighten x86 /dev/mem with zeroing readsKees Cook
Under CONFIG_STRICT_DEVMEM, reading System RAM through /dev/mem is disallowed. However, on x86, the first 1MB was always allowed for BIOS and similar things, regardless of it actually being System RAM. It was possible for heap to end up getting allocated in low 1MB RAM, and then read by things like x86info or dd, which would trip hardened usercopy: usercopy: kernel memory exposure attempt detected from ffff880000090000 (dma-kmalloc-256) (4096 bytes) This changes the x86 exception for the low 1MB by reading back zeros for System RAM areas instead of blindly allowing them. More work is needed to extend this to mmap, but currently mmap doesn't go through usercopy, so hardened usercopy won't Oops the kernel. Reported-by: Tommi Rantala <tommi.t.rantala@nokia.com> Tested-by: Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-11x86/intel_rdt: Fix locking in rdtgroup_schemata_write()Jiri Olsa
The schemata lock is released before freeing the resource's temporary tmp_cbms allocation. That's racy versus another write which allocates and uses new temporary storage, resulting in memory leaks, freeing in use memory, double a free or any combination of those. Move the unlock after the release code. Fixes: 60ec2440c63d ("x86/intel_rdt: Add schemata file") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Shaohua Li <shli@fb.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170411071446.15241-1-jolsa@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-11x86/debug: Fix the printk() debug output of signal_fault(), do_trap() and ↵Markus Trippelsdorf
do_general_protection() Since commit: 4bcc595ccd80 "printk: reinstate KERN_CONT for printing" ... the debug output of signal_fault(), do_trap() and do_general_protection() looks garbled, e.g.: traps: conftest[9335] trap invalid opcode ip:400428 sp:7ffeaba1b0d8 error:0 in conftest[400000+1000] (note the unintended line break.) Fix the bug by adding KERN_CONTs. Signed-off-by: Markus Trippelsdorf <markus@trippelsdorf.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-11Backmerge tag 'v4.11-rc6' into drm-nextDave Airlie
Linux 4.11-rc6 drm-misc needs 4.11-rc5, may as well fix conflicts with rc6.
2017-04-10x86/vdso: Plug race between mapping and ELF header setupThomas Gleixner
The vsyscall32 sysctl can racy against a concurrent fork when it switches from disabled to enabled: arch_setup_additional_pages() if (vdso32_enabled) --> No mapping sysctl.vsysscall32() --> vdso32_enabled = true create_elf_tables() ARCH_DLINFO_IA32 if (vdso32_enabled) { --> Add VDSO entry with NULL pointer Make ARCH_DLINFO_IA32 check whether the VDSO mapping has been set up for the newly forked process or not. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@amacapital.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mathias Krause <minipli@googlemail.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170410151723.602367196@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-10x86/vdso: Ensure vdso32_enabled gets set to valid values onlyMathias Krause
vdso_enabled can be set to arbitrary integer values via the kernel command line 'vdso32=' parameter or via 'sysctl abi.vsyscall32'. load_vdso32() only maps VDSO if vdso_enabled == 1, but ARCH_DLINFO_IA32 merily checks for vdso_enabled != 0. As a consequence the AT_SYSINFO_EHDR auxiliary vector for the VDSO_ENTRY is emitted with a NULL pointer which causes a segfault when the application tries to use the VDSO. Restrict the valid arguments on the command line and the sysctl to 0 and 1. Fixes: b0b49f2673f0 ("x86, vdso: Remove compat vdso support") Signed-off-by: Mathias Krause <minipli@googlemail.com> Acked-by: Andy Lutomirski <luto@amacapital.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Cc: Roland McGrath <roland@redhat.com> Link: http://lkml.kernel.org/r/1491424561-7187-1-git-send-email-minipli@googlemail.com Link: http://lkml.kernel.org/r/20170410151723.518412863@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-08Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Radim Krčmář: "ARM: - Fix a problem with GICv3 userspace save/restore - Clarify GICv2 userspace save/restore ABI - Be more careful in clearing GIC LRs - Add missing synchronization primitive to our MMU handling code PPC: - Check for a NULL return from kzalloc s390: - Prevent translation exception errors on valid page tables for the instruction-exection-protection support x86: - Fix Page-Modification Logging when running a nested guest" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: PPC: Book3S HV: Check for kmalloc errors in ioctl KVM: nVMX: initialize PML fields in vmcs02 KVM: nVMX: do not leak PML full vmexit to L1 KVM: arm/arm64: vgic: Fix GICC_PMR uaccess on GICv3 and clarify ABI KVM: arm64: Ensure LRs are clear when they should be kvm: arm/arm64: Fix locking for kvm_free_stage2_pgd KVM: s390: remove change-recording override support arm/arm64: KVM: Take mmap_sem in kvm_arch_prepare_memory_region arm/arm64: KVM: Take mmap_sem in stage2_unmap_vm
2017-04-05x86/signals: Fix lower/upper bound reporting in compat siginfoJoerg Roedel
Put the right values from the original siginfo into the userspace compat-siginfo. This fixes the 32-bit MPX "tabletest" testcase on 64-bit kernels. Signed-off-by: Joerg Roedel <jroedel@suse.de> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: <stable@vger.kernel.org> # v4.8+ Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: a4455082dc6f0 ('x86/signals: Add missing signal_compat code for x86 features') Link: http://lkml.kernel.org/r/1491322501-5054-1-git-send-email-joro@8bytes.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-04KVM: nVMX: initialize PML fields in vmcs02Ladi Prosek
L2 was running with uninitialized PML fields which led to incomplete dirty bitmap logging. This manifested as all kinds of subtle erratic behavior of the nested guest. Fixes: 843e4330573c ("KVM: VMX: Add PML support in VMX") Signed-off-by: Ladi Prosek <lprosek@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-04-04KVM: nVMX: do not leak PML full vmexit to L1Ladi Prosek
The PML feature is not exposed to guests so we should not be forwarding the vmexit either. This commit fixes BSOD 0x20001 (HYPERVISOR_ERROR) when running Hyper-V enabled Windows Server 2016 in L1 on hardware that supports PML. Fixes: 843e4330573c ("KVM: VMX: Add PML support in VMX") Signed-off-by: Ladi Prosek <lprosek@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-04-03Merge branch 'ras-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RAS fix from Thomas Gleixner: "Prevent dmesg from being spammed when MCE logging is active" * 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Don't print MCEs when mcelog is active
2017-04-02Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "This update provides: - prevent KASLR from randomizing EFI regions - restrict the usage of -maccumulate-outgoing-args and document when and why it is required. - make the Global Physical Address calculation for UV4 systems work correctly. - address a copy->paste->forgot-edit problem in the MCE exception table entries. - assign a name to AMD MCA bank 3, so the sysfs file registration works. - add a missing include in the boot code" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Include missing header file x86/mce/AMD: Give a name to MCA bank 3 when accessed with legacy MSRs x86/build: Mostly disable '-maccumulate-outgoing-args' x86/mm/KASLR: Exclude EFI region from KASLR VA space randomization x86/mce: Fix copy/paste error in exception table entries x86/platform/uv: Fix calculation of Global Physical Address
2017-04-02Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Thomas Gleixner: "This update provides: - make the scheduler clock switch to unstable mode smooth so the timestamps stay at microseconds granularity instead of switching to tick granularity. - unbreak perf test tsc by taking the new offset into account which was added in order to proveide better sched clock continuity - switching sched clock to unstable mode runs all clock related computations which affect the sched clock output itself from a work queue. In case of preemption sched clock uses half updated data and provides wrong timestamps. Keep the math in the protected context and delegate only the static key switch to workqueue context. - remove a duplicate header include" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/headers: Remove duplicate #include <linux/sched/debug.h> line sched/clock: Fix broken stable to unstable transfer sched/clock, x86/perf: Fix "perf test tsc" sched/clock: Fix clear_sched_clock_stable() preempt wobbly
2017-03-31kasan: do not sanitize kexec purgatoryMike Galbraith
Fixes this: kexec: Undefined symbol: __asan_load8_noabort kexec-bzImage64: Loading purgatory failed Link: http://lkml.kernel.org/r/1489672155.4458.7.camel@gmx.de Signed-off-by: Mike Galbraith <efault@gmx.de> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-31x86/boot: Include missing header fileZhengyi Shen
Sparse complains about missing forward declarations: arch/x86/boot/compressed/error.c:8:6: warning: symbol 'warn' was not declared. Should it be static? arch/x86/boot/compressed/error.c:15:6: warning: symbol 'error' was not declared. Should it be static? Include the missing header file. Signed-off-by: Zhengyi Shen <shenzhengyi@gmail.com> Acked-by: Kess Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/1490770820-24472-1-git-send-email-shenzhengyi@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-31x86/mce/AMD: Give a name to MCA bank 3 when accessed with legacy MSRsYazen Ghannam
MCA bank 3 is reserved on systems pre-Fam17h, so it didn't have a name. However, MCA bank 3 is defined on Fam17h systems and can be accessed using legacy MSRs. Without a name we get a stack trace on Fam17h systems when trying to register sysfs files for bank 3 on kernels that don't recognize Scalable MCA. Call MCA bank 3 "decode_unit" since this is what it represents on Fam17h. This will allow kernels without SMCA support to see this bank on Fam17h+ and prevent the stack trace. This will not affect older systems since this bank is reserved on them, i.e. it'll be ignored. Tested on AMD Fam15h and Fam17h systems. WARNING: CPU: 26 PID: 1 at lib/kobject.c:210 kobject_add_internal kobject: (ffff88085bb256c0): attempted to be registered with empty name! ... Call Trace: kobject_add_internal kobject_add kobject_create_and_add threshold_create_device threshold_init_device Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1490102285-3659-1-git-send-email-Yazen.Ghannam@amd.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-30x86/build: Mostly disable '-maccumulate-outgoing-args'Josh Poimboeuf
The GCC '-maccumulate-outgoing-args' flag is enabled for most configs, mostly because of issues which are no longer relevant. For most configs, and with most recent versions of GCC, it's no longer needed. Clarify which cases need it, and only enable it for those cases. Also produce a compile-time error for the ftrace graph + mcount + '-Os' case, which will otherwise cause runtime failures. The main benefit of '-maccumulate-outgoing-args' is that it prevents an ugly prologue for functions which have aligned stacks. But removing the option also has some benefits: more readable argument saves, smaller text size, and (presumably) slightly improved performance. Here are the object size savings for 32-bit and 64-bit defconfig kernels: text data bss dec hex filename 10006710 3543328 1773568 15323606 e9d1d6 vmlinux.x86-32.before 9706358 3547424 1773568 15027350 e54c96 vmlinux.x86-32.after text data bss dec hex filename 10652105 4537576 843776 16033457 f4a6b1 vmlinux.x86-64.before 10639629 4537576 843776 16020981 f475f5 vmlinux.x86-64.after That comes out to a 3% text size improvement on x86-32 and a 0.1% text size improvement on x86-64. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andrew Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170316193133.zrj6gug53766m6nn@treble Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-28KVM: x86: cleanup the page tracking SRCU instancePaolo Bonzini
SRCU uses a delayed work item. Skip cleaning it up, and the result is use-after-free in the work item callbacks. Reported-by: Dmitry Vyukov <dvyukov@google.com> Suggested-by: Dmitry Vyukov <dvyukov@google.com> Cc: stable@vger.kernel.org Fixes: 0eb05bf290cfe8610d9680b49abef37febd1c38a Reviewed-by: Xiao Guangrong <xiaoguangrong.eric@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-28KVM: nVMX: fix nested EPT detectionLadi Prosek
The nested_ept_enabled flag introduced in commit 7ca29de2136 was not computed correctly. We are interested only in L1's EPT state, not the the combined L0+L1 value. In particular, if L0 uses EPT but L1 does not, nested_ept_enabled must be false to make sure that PDPSTRs are loaded based on CR3 as usual, because the special case described in 26.3.2.4 Loading Page-Directory- Pointer-Table Entries does not apply. Fixes: 7ca29de21362 ("KVM: nVMX: fix CR3 load if L2 uses PAE paging and EPT") Cc: qemu-stable@nongnu.org Reported-by: Wanpeng Li <wanpeng.li@hotmail.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Ladi Prosek <lprosek@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-28x86/mce: Don't print MCEs when mcelog is activeAndi Kleen
Since: cd9c57cad3fe ("x86/MCE: Dump MCE to dmesg if no consumers") all MCEs are printed even when mcelog is running. Fix the regression to not print to dmesg when mcelog is running as it is a consumer too. Signed-off-by: Andi Kleen <ak@linux.intel.com> [ Massage commit message. ] Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: stable@vger.kernel.org # 4.10.. Fixes: cd9c57cad3fe ("x86/MCE: Dump MCE to dmesg if no consumers") Link: http://lkml.kernel.org/r/20170327093304.10683-2-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-24x86/mm/KASLR: Exclude EFI region from KASLR VA space randomizationBaoquan He
Currently KASLR is enabled on three regions: the direct mapping of physical memory, vamlloc and vmemmap. However the EFI region is also mistakenly included for VA space randomization because of misusing EFI_VA_START macro and assuming EFI_VA_START < EFI_VA_END. (This breaks kexec and possibly other things that rely on stable addresses.) The EFI region is reserved for EFI runtime services virtual mapping which should not be included in KASLR ranges. In Documentation/x86/x86_64/mm.txt, we can see: ffffffef00000000 - fffffffeffffffff (=64 GB) EFI region mapping space EFI uses the space from -4G to -64G thus EFI_VA_START > EFI_VA_END, Here EFI_VA_START = -4G, and EFI_VA_END = -64G. Changing EFI_VA_START to EFI_VA_END in mm/kaslr.c fixes this problem. Signed-off-by: Baoquan He <bhe@redhat.com> Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com> Acked-by: Dave Young <dyoung@redhat.com> Acked-by: Thomas Garnier <thgarnie@google.com> Cc: <stable@vger.kernel.org> #4.8+ Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1490331592-31860-1-git-send-email-bhe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-23KVM: VMX: Fix enable VPID conditionsWanpeng Li
This can be reproduced by running L2 on L1, and disable VPID on L0 if w/o commit "KVM: nVMX: Fix nested VPID vmx exec control", the L2 crash as below: KVM: entry failed, hardware error 0x7 EAX=00000000 EBX=00000000 ECX=00000000 EDX=000306c3 ESI=00000000 EDI=00000000 EBP=00000000 ESP=00000000 EIP=0000fff0 EFL=00000002 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0 ES =0000 00000000 0000ffff 00009300 CS =f000 ffff0000 0000ffff 00009b00 SS =0000 00000000 0000ffff 00009300 DS =0000 00000000 0000ffff 00009300 FS =0000 00000000 0000ffff 00009300 GS =0000 00000000 0000ffff 00009300 LDT=0000 00000000 0000ffff 00008200 TR =0000 00000000 0000ffff 00008b00 GDT= 00000000 0000ffff IDT= 00000000 0000ffff CR0=60000010 CR2=00000000 CR3=00000000 CR4=00000000 DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 DR3=0000000000000000 DR6=00000000ffff0ff0 DR7=0000000000000400 EFER=0000000000000000 Reference SDM 30.3 INVVPID: Protected Mode Exceptions - #UD - If not in VMX operation. - If the logical processor does not support VPIDs (IA32_VMX_PROCBASED_CTLS2[37]=0). - If the logical processor supports VPIDs (IA32_VMX_PROCBASED_CTLS2[37]=1) but does not support the INVVPID instruction (IA32_VMX_EPT_VPID_CAP[32]=0). So we should check both VPID enable bit in vmx exec control and INVVPID support bit in vmx capability MSRs to enable VPID. This patch adds the guarantee to not enable VPID if either INVVPID or single-context/all-context invalidation is not exposed in vmx capability MSRs. Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Jim Mattson <jmattson@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-23KVM: nVMX: Fix nested VPID vmx exec controlWanpeng Li
This can be reproduced by running kvm-unit-tests/vmx.flat on L0 w/ vpid disabled. Test suite: VPID Unhandled exception 6 #UD at ip 00000000004051a6 error_code=0000 rflags=00010047 cs=00000008 rax=0000000000000000 rcx=0000000000000001 rdx=0000000000000047 rbx=0000000000402f79 rbp=0000000000456240 rsi=0000000000000001 rdi=0000000000000000 r8=000000000000000a r9=00000000000003f8 r10=0000000080010011 r11=0000000000000000 r12=0000000000000003 r13=0000000000000708 r14=0000000000000000 r15=0000000000000000 cr0=0000000080010031 cr2=0000000000000000 cr3=0000000007fff000 cr4=0000000000002020 cr8=0000000000000000 STACK: @4051a6 40523e 400f7f 402059 40028f We should hide and forbid VPID in L1 if it is disabled on L0. However, nested VPID enable bit is set unconditionally during setup nested vmx exec controls though VPID is not exposed through nested VMX capablity. This patch fixes it by don't set nested VPID enable bit if it is disabled on L0. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: stable@vger.kernel.org Fixes: 5c614b3583e (KVM: nVMX: nested VPID emulation) Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-23KVM: x86: correct async page present tracepointWanpeng Li
After async pf setup successfully, there is a broadcast wakeup w/ special token 0xffffffff which tells vCPU that it should wake up all processes waiting for APFs though there is no real process waiting at the moment. The async page present tracepoint print prematurely and fails to catch the special token setup. This patch fixes it by moving the async page present tracepoint after the special token setup. Before patch: qemu-system-x86-8499 [006] ...1 5973.473292: kvm_async_pf_ready: token 0x0 gva 0x0 After patch: qemu-system-x86-8499 [006] ...1 5973.473292: kvm_async_pf_ready: token 0xffffffff gva 0x0 Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-23kvm: vmx: Flush TLB when the APIC-access address changesJim Mattson
Quoting from the Intel SDM, volume 3, section 28.3.3.4: Guidelines for Use of the INVEPT Instruction: If EPT was in use on a logical processor at one time with EPTP X, it is recommended that software use the INVEPT instruction with the "single-context" INVEPT type and with EPTP X in the INVEPT descriptor before a VM entry on the same logical processor that enables EPT with EPTP X and either (a) the "virtualize APIC accesses" VM-execution control was changed from 0 to 1; or (b) the value of the APIC-access address was changed. In the nested case, the burden falls on L1, unless L0 enables EPT in vmcs02 when L1 doesn't enable EPT in vmcs12. Signed-off-by: Jim Mattson <jmattson@google.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-03-23KVM: x86: use pic/ioapic destructor when destroy vmPeter Xu
We have specific destructors for pic/ioapic, we'd better use them when destroying the VM as well. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-03-23KVM: x86: check existance before destroyPeter Xu
Mostly used for split irqchip mode. In that case, these two things are not inited at all, so no need to release. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-03-23sched/clock, x86/perf: Fix "perf test tsc"Peter Zijlstra
People reported that commit: 5680d8094ffa ("sched/clock: Provide better clock continuity") broke "perf test tsc". That commit added another offset to the reported clock value; so take that into account when computing the provided offset values. Reported-by: Adrian Hunter <adrian.hunter@intel.com> Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org> Tested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 5680d8094ffa ("sched/clock: Provide better clock continuity") Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-23BackMerge tag 'v4.11-rc3' into drm-nextDave Airlie
Linux 4.11-rc3 as requested by Daniel
2017-03-22x86/mce: Fix copy/paste error in exception table entriesTony Luck
Back in commit: 92b0729c34cab ("x86/mm, x86/mce: Add memcpy_mcsafe()") ... I made a copy/paste error setting up the exception table entries and ended up with two for label .L_cache_w3 and none for .L_cache_w2. This means that if we take a machine check on: .L_cache_w2: movq 2*8(%rsi), %r10 then we don't have an exception table entry for this instruction and we can't recover. Fix: s/3/2/ Signed-off-by: Tony Luck <tony.luck@intel.com> Cc: <stable@vger.kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 92b0729c34cab ("x86/mm, x86/mce: Add memcpy_mcsafe()") Link: http://lkml.kernel.org/r/1490046030-25862-1-git-send-email-tony.luck@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-22x86/platform/uv: Fix calculation of Global Physical AddressMike Travis
The calculation of the global physical address (GPA) on UV4 is incorrect. The gnode_extra/upper global offset should only be applied for fixed address space systems (UV1..3). Tested-by: John Estabrook <john.estabrook@hpe.com> Signed-off-by: Mike Travis <mike.travis@hpe.com> Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com> Cc: John Estabrook <estabrook@sgi.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <russ.anderson@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170321231646.667689538@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-20KVM: nVMX: don't reset kvm mmu twiceWanpeng Li
kvm mmu is reset once successfully loading CR3 as part of emulating vmentry in nested_vmx_load_cr3(). We should not reset kvm mmu twice. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-03-20kvm: fix usage of uninit spinlock in avic_vm_destroy()Dmitry Vyukov
If avic is not enabled, avic_vm_init() does nothing and returns early. However, avic_vm_destroy() still tries to destroy what hasn't been created. The only bad consequence of this now is that avic_vm_destroy() uses svm_vm_data_hash_lock that hasn't been initialized (and is not meant to be used at all if avic is not enabled). Return early from avic_vm_destroy() if avic is not enabled. It has nothing to destroy. Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: kvm@vger.kernel.org Cc: syzkaller@googlegroups.com Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-03-20KVM: VMX: downgrade warning on unexpected exit codeRadim Krčmář
We never needed the call trace and we better rate-limit if it can be triggered by a guest. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-03-17Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "An assorted pile of fixes along with some hardware enablement: - a fix for a KASAN / branch profiling related boot failure - some more fallout of the PUD rework - a fix for the Always Running Timer which is not initialized when the TSC frequency is known at boot time (via MSR/CPUID) - a resource leak fix for the RDT filesystem - another unwinder corner case fixup - removal of the warning for duplicate NMI handlers because there are legitimate cases where more than one handler can be registered at the last level - make a function static - found by sparse - a set of updates for the Intel MID platform which got delayed due to merge ordering constraints. It's hardware enablement for a non mainstream platform, so there is no risk" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mpx: Make unnecessarily global function static x86/intel_rdt: Put group node in rdtgroup_kn_unlock x86/unwind: Fix last frame check for aligned function stacks mm, x86: Fix native_pud_clear build error x86/kasan: Fix boot with KASAN=y and PROFILE_ANNOTATED_BRANCHES=y x86/platform/intel-mid: Add power button support for Merrifield x86/platform/intel-mid: Use common power off sequence x86/platform: Remove warning message for duplicate NMI handlers x86/tsc: Fix ART for TSC_KNOWN_FREQ x86/platform/intel-mid: Correct MSI IRQ line for watchdog device
2017-03-17Merge branch 'x86-acpi-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 acpi fixes from Thomas Gleixner: "This update deals with the fallout of the recent work to make cpuid/node mappings persistent. It turned out that the boot time ACPI based mapping tripped over ACPI inconsistencies and caused regressions. It's partially reverted and the fragile part replaced by an implementation which makes the mapping persistent when a CPU goes online for the first time" * 'x86-acpi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: acpi/processor: Check for duplicate processor ids at hotplug time acpi/processor: Implement DEVICE operator for processor enumeration x86/acpi: Restore the order of CPU IDs Revert"x86/acpi: Enable MADT APIs to return disabled apicids" Revert "x86/acpi: Set persistent cpuid <-> nodeid mapping when booting"
2017-03-17Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "A set of perf related fixes: - fix a CR4.PCE propagation issue caused by usage of mm instead of active_mm and therefore propagated the wrong value. - perf core fixes, which plug a use-after-free issue and make the event inheritance on fork more robust. - a tooling fix for symbol handling" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf symbols: Fix symbols__fixup_end heuristic for corner cases x86/perf: Clarify why x86_pmu_event_mapped() isn't racy x86/perf: Fix CR4.PCE propagation to use active_mm instead of mm perf/core: Better explain the inherit magic perf/core: Simplify perf_event_free_task() perf/core: Fix event inheritance on fork() perf/core: Fix use-after-free in perf_release()
2017-03-17x86/perf: Clarify why x86_pmu_event_mapped() isn't racyAndy Lutomirski
Naively, it looks racy, but ->mmap_sem saves it. Add a comment and a lockdep assertion. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bpetkov@suse.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/03a1e629063899168dfc4707f3bb6e581e21f5c6.1489694270.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-17x86/perf: Fix CR4.PCE propagation to use active_mm instead of mmAndy Lutomirski
If one thread mmaps a perf event while another thread in the same mm is in some context where active_mm != mm (which can happen in the scheduler, for example), refresh_pce() would write the wrong value to CR4.PCE. This broke some PAPI tests. Reported-and-tested-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bpetkov@suse.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Fixes: 7911d3f7af14 ("perf/x86: Only allow rdpmc if a perf_event is mapped") Link: http://lkml.kernel.org/r/0c5b38a76ea50e405f9abe07a13dfaef87c173a1.1489694270.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-16mm, x86: fix native_pud_clear build errorArnd Bergmann
We still get a build error in random configurations, after this has been modified a few times: In file included from include/linux/mm.h:68:0, from include/linux/suspend.h:8, from arch/x86/kernel/asm-offsets.c:12: arch/x86/include/asm/pgtable.h:66:26: error: redefinition of 'native_pud_clear' #define pud_clear(pud) native_pud_clear(pud) My interpretation is that the build error comes from a typo in __PAGETABLE_PUD_FOLDED, so fix that typo now, and remove the incorrect #ifdef around the native_pud_clear definition. Fixes: 3e761a42e19c ("mm, x86: fix HIGHMEM64 && PARAVIRT build config for native_pud_clear()") Fixes: a00cc7d9dd93 ("mm, x86: add support for PUD-sized transparent hugepages") Link: http://lkml.kernel.org/r/20170314121330.182155-1-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Ackedy-by: Dave Jiang <dave.jiang@intel.com> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Garnier <thgarnie@google.com> Cc: Kees Cook <keescook@chromium.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Borislav Petkov <bp@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-16x86/mpx: Make unnecessarily global function staticTobias Klauser
Make the function get_user_bd_entry() static as it is not used outside of arch/x86/mm/mpx.c This fixes a sparse warning. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-14x86/intel_rdt: Put group node in rdtgroup_kn_unlockJiri Olsa
The rdtgroup_kn_unlock waits for the last user to release and put its node. But it's calling kernfs_put on the node which calls the rdtgroup_kn_unlock, which might not be the group's directory node, but another group's file node. This race could be easily reproduced by running 2 instances of following script: mount -t resctrl resctrl /sys/fs/resctrl/ pushd /sys/fs/resctrl/ mkdir krava echo "krava" > krava/schemata rmdir krava popd umount /sys/fs/resctrl It triggers the slub debug error message with following command line config: slub_debug=,kernfs_node_cache. Call kernfs_put on the group's node to fix it. Fixes: 60cf5e101fd4 ("x86/intel_rdt: Add mkdir to resctrl file system") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Shaohua Li <shli@fb.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1489501253-20248-1-git-send-email-jolsa@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>