1. 17 12月, 2017 1 次提交
    • A
      x86/entry/64: Allocate and enable the SYSENTER stack · 1a79797b
      Andy Lutomirski 提交于
      This will simplify future changes that want scratch variables early in
      the SYSENTER handler -- they'll be able to spill registers to the
      stack.  It also lets us get rid of a SWAPGS_UNSAFE_STACK user.
      
      This does not depend on CONFIG_IA32_EMULATION=y because we'll want the
      stack space even without IA32 emulation.
      
      As far as I can tell, the reason that this wasn't done from day 1 is
      that we use IST for #DB and #BP, which is IMO rather nasty and causes
      a lot more problems than it solves.  But, since #DB uses IST, we don't
      actually need a real stack for SYSENTER (because SYSENTER with TF set
      will invoke #DB on the IST stack rather than the SYSENTER stack).
      
      I want to remove IST usage from these vectors some day, and this patch
      is a prerequisite for that as well.
      Signed-off-by: NAndy Lutomirski <luto@kernel.org>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
      Reviewed-by: NBorislav Petkov <bp@suse.de>
      Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bpetkov@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: David Laight <David.Laight@aculab.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Eduardo Valentin <eduval@amazon.com>
      Cc: Greg KH <gregkh@linuxfoundation.org>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: aliguori@amazon.com
      Cc: daniel.gruss@iaik.tugraz.at
      Cc: hughd@google.com
      Cc: keescook@google.com
      Link: https://lkml.kernel.org/r/20171204150605.312726423@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      1a79797b
  2. 02 11月, 2017 2 次提交
  3. 17 10月, 2017 1 次提交
  4. 18 9月, 2017 1 次提交
  5. 13 9月, 2017 1 次提交
    • A
      x86/mm/64: Initialize CR4.PCIDE early · c7ad5ad2
      Andy Lutomirski 提交于
      cpu_init() is weird: it's called rather late (after early
      identification and after most MMU state is initialized) on the boot
      CPU but is called extremely early (before identification) on secondary
      CPUs.  It's called just late enough on the boot CPU that its CR4 value
      isn't propagated to mmu_cr4_features.
      
      Even if we put CR4.PCIDE into mmu_cr4_features, we'd hit two
      problems.  First, we'd crash in the trampoline code.  That's
      fixable, and I tried that.  It turns out that mmu_cr4_features is
      totally ignored by secondary_start_64(), though, so even with the
      trampoline code fixed, it wouldn't help.
      
      This means that we don't currently have CR4.PCIDE reliably initialized
      before we start playing with cpu_tlbstate.  This is very fragile and
      tends to cause boot failures if I make even small changes to the TLB
      handling code.
      
      Make it more robust: initialize CR4.PCIDE earlier on the boot CPU
      and propagate it to secondary CPUs in start_secondary().
      
      ( Yes, this is ugly.  I think we should have improved mmu_cr4_features
        to actually control CR4 during secondary bootup, but that would be
        fairly intrusive at this stage. )
      Signed-off-by: NAndy Lutomirski <luto@kernel.org>
      Reported-by: NSai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
      Tested-by: NSai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
      Cc: Borislav Petkov <bpetkov@suse.de>
      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
      Fixes: 660da7c9 ("x86/mm: Enable CR4.PCIDE on supported systems")
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      c7ad5ad2
  6. 07 9月, 2017 2 次提交
  7. 29 8月, 2017 1 次提交
  8. 05 7月, 2017 2 次提交
  9. 02 5月, 2017 1 次提交
  10. 23 3月, 2017 2 次提交
  11. 16 3月, 2017 2 次提交
    • T
      x86: Make the GDT remapping read-only on 64-bit · 45fc8757
      Thomas Garnier 提交于
      This patch makes the GDT remapped pages read-only, to prevent accidental
      (or intentional) corruption of this key data structure.
      
      This change is done only on 64-bit, because 32-bit needs it to be writable
      for TSS switches.
      
      The native_load_tr_desc function was adapted to correctly handle a
      read-only GDT. The LTR instruction always writes to the GDT TSS entry.
      This generates a page fault if the GDT is read-only. This change checks
      if the current GDT is a remap and swap GDTs as needed. This function was
      tested by booting multiple machines and checking hibernation works
      properly.
      
      KVM SVM and VMX were adapted to use the writeable GDT. On VMX, the
      per-cpu variable was removed for functions to fetch the original GDT.
      Instead of reloading the previous GDT, VMX will reload the fixmap GDT as
      expected. For testing, VMs were started and restored on multiple
      configurations.
      Signed-off-by: NThomas Garnier <thgarnie@google.com>
      Cc: Alexander Potapenko <glider@google.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jiri Kosina <jikos@kernel.org>
      Cc: Joerg Roedel <joro@8bytes.org>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Len Brown <len.brown@intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Lorenzo Stoakes <lstoakes@gmail.com>
      Cc: Luis R . Rodriguez <mcgrof@kernel.org>
      Cc: Matt Fleming <matt@codeblueprint.co.uk>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Pavel Machek <pavel@ucw.cz>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Radim Krčmář <rkrcmar@redhat.com>
      Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: Stanislaw Gruszka <sgruszka@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tim Chen <tim.c.chen@linux.intel.com>
      Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
      Cc: kasan-dev@googlegroups.com
      Cc: kernel-hardening@lists.openwall.com
      Cc: kvm@vger.kernel.org
      Cc: lguest@lists.ozlabs.org
      Cc: linux-doc@vger.kernel.org
      Cc: linux-efi@vger.kernel.org
      Cc: linux-mm@kvack.org
      Cc: linux-pm@vger.kernel.org
      Cc: xen-devel@lists.xenproject.org
      Cc: zijun_hu <zijun_hu@htc.com>
      Link: http://lkml.kernel.org/r/20170314170508.100882-3-thgarnie@google.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      45fc8757
    • T
      x86: Remap GDT tables in the fixmap section · 69218e47
      Thomas Garnier 提交于
      Each processor holds a GDT in its per-cpu structure. The sgdt
      instruction gives the base address of the current GDT. This address can
      be used to bypass KASLR memory randomization. With another bug, an
      attacker could target other per-cpu structures or deduce the base of
      the main memory section (PAGE_OFFSET).
      
      This patch relocates the GDT table for each processor inside the
      fixmap section. The space is reserved based on number of supported
      processors.
      
      For consistency, the remapping is done by default on 32 and 64-bit.
      
      Each processor switches to its remapped GDT at the end of
      initialization. For hibernation, the main processor returns with the
      original GDT and switches back to the remapping at completion.
      
      This patch was tested on both architectures. Hibernation and KVM were
      both tested specially for their usage of the GDT.
      
      Thanks to Boris Ostrovsky <boris.ostrovsky@oracle.com> for testing and
      recommending changes for Xen support.
      Signed-off-by: NThomas Garnier <thgarnie@google.com>
      Cc: Alexander Potapenko <glider@google.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jiri Kosina <jikos@kernel.org>
      Cc: Joerg Roedel <joro@8bytes.org>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Len Brown <len.brown@intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Lorenzo Stoakes <lstoakes@gmail.com>
      Cc: Luis R . Rodriguez <mcgrof@kernel.org>
      Cc: Matt Fleming <matt@codeblueprint.co.uk>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Pavel Machek <pavel@ucw.cz>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Radim Krčmář <rkrcmar@redhat.com>
      Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: Stanislaw Gruszka <sgruszka@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tim Chen <tim.c.chen@linux.intel.com>
      Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
      Cc: kasan-dev@googlegroups.com
      Cc: kernel-hardening@lists.openwall.com
      Cc: kvm@vger.kernel.org
      Cc: lguest@lists.ozlabs.org
      Cc: linux-doc@vger.kernel.org
      Cc: linux-efi@vger.kernel.org
      Cc: linux-mm@kvack.org
      Cc: linux-pm@vger.kernel.org
      Cc: xen-devel@lists.xenproject.org
      Cc: zijun_hu <zijun_hu@htc.com>
      Link: http://lkml.kernel.org/r/20170314170508.100882-2-thgarnie@google.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      69218e47
  12. 03 3月, 2017 1 次提交
    • I
      sched/headers: Move task->mm handling methods to <linux/sched/mm.h> · 68e21be2
      Ingo Molnar 提交于
      Move the following task->mm helper APIs into a new header file,
      <linux/sched/mm.h>, to further reduce the size and complexity
      of <linux/sched.h>.
      
      Here are how the APIs are used in various kernel files:
      
        # mm_alloc():
        arch/arm/mach-rpc/ecard.c
        fs/exec.c
        include/linux/sched/mm.h
        kernel/fork.c
      
        # __mmdrop():
        arch/arc/include/asm/mmu_context.h
        include/linux/sched/mm.h
        kernel/fork.c
      
        # mmdrop():
        arch/arm/mach-rpc/ecard.c
        arch/m68k/sun3/mmu_emu.c
        arch/x86/mm/tlb.c
        drivers/gpu/drm/amd/amdkfd/kfd_process.c
        drivers/gpu/drm/i915/i915_gem_userptr.c
        drivers/infiniband/hw/hfi1/file_ops.c
        drivers/vfio/vfio_iommu_spapr_tce.c
        fs/exec.c
        fs/proc/base.c
        fs/proc/task_mmu.c
        fs/proc/task_nommu.c
        fs/userfaultfd.c
        include/linux/mmu_notifier.h
        include/linux/sched/mm.h
        kernel/fork.c
        kernel/futex.c
        kernel/sched/core.c
        mm/khugepaged.c
        mm/ksm.c
        mm/mmu_context.c
        mm/mmu_notifier.c
        mm/oom_kill.c
        virt/kvm/kvm_main.c
      
        # mmdrop_async_fn():
        include/linux/sched/mm.h
      
        # mmdrop_async():
        include/linux/sched/mm.h
        kernel/fork.c
      
        # mmget_not_zero():
        fs/userfaultfd.c
        include/linux/sched/mm.h
        mm/oom_kill.c
      
        # mmput():
        arch/arc/include/asm/mmu_context.h
        arch/arc/kernel/troubleshoot.c
        arch/frv/mm/mmu-context.c
        arch/powerpc/platforms/cell/spufs/context.c
        arch/sparc/include/asm/mmu_context_32.h
        drivers/android/binder.c
        drivers/gpu/drm/etnaviv/etnaviv_gem.c
        drivers/gpu/drm/i915/i915_gem_userptr.c
        drivers/infiniband/core/umem.c
        drivers/infiniband/core/umem_odp.c
        drivers/infiniband/core/uverbs_main.c
        drivers/infiniband/hw/mlx4/main.c
        drivers/infiniband/hw/mlx5/main.c
        drivers/infiniband/hw/usnic/usnic_uiom.c
        drivers/iommu/amd_iommu_v2.c
        drivers/iommu/intel-svm.c
        drivers/lguest/lguest_user.c
        drivers/misc/cxl/fault.c
        drivers/misc/mic/scif/scif_rma.c
        drivers/oprofile/buffer_sync.c
        drivers/vfio/vfio_iommu_type1.c
        drivers/vhost/vhost.c
        drivers/xen/gntdev.c
        fs/exec.c
        fs/proc/array.c
        fs/proc/base.c
        fs/proc/task_mmu.c
        fs/proc/task_nommu.c
        fs/userfaultfd.c
        include/linux/sched/mm.h
        kernel/cpuset.c
        kernel/events/core.c
        kernel/events/uprobes.c
        kernel/exit.c
        kernel/fork.c
        kernel/ptrace.c
        kernel/sys.c
        kernel/trace/trace_output.c
        kernel/tsacct.c
        mm/memcontrol.c
        mm/memory.c
        mm/mempolicy.c
        mm/migrate.c
        mm/mmu_notifier.c
        mm/nommu.c
        mm/oom_kill.c
        mm/process_vm_access.c
        mm/rmap.c
        mm/swapfile.c
        mm/util.c
        virt/kvm/async_pf.c
      
        # mmput_async():
        include/linux/sched/mm.h
        kernel/fork.c
        mm/oom_kill.c
      
        # get_task_mm():
        arch/arc/kernel/troubleshoot.c
        arch/powerpc/platforms/cell/spufs/context.c
        drivers/android/binder.c
        drivers/gpu/drm/etnaviv/etnaviv_gem.c
        drivers/infiniband/core/umem.c
        drivers/infiniband/core/umem_odp.c
        drivers/infiniband/hw/mlx4/main.c
        drivers/infiniband/hw/mlx5/main.c
        drivers/infiniband/hw/usnic/usnic_uiom.c
        drivers/iommu/amd_iommu_v2.c
        drivers/iommu/intel-svm.c
        drivers/lguest/lguest_user.c
        drivers/misc/cxl/fault.c
        drivers/misc/mic/scif/scif_rma.c
        drivers/oprofile/buffer_sync.c
        drivers/vfio/vfio_iommu_type1.c
        drivers/vhost/vhost.c
        drivers/xen/gntdev.c
        fs/proc/array.c
        fs/proc/base.c
        fs/proc/task_mmu.c
        include/linux/sched/mm.h
        kernel/cpuset.c
        kernel/events/core.c
        kernel/exit.c
        kernel/fork.c
        kernel/ptrace.c
        kernel/sys.c
        kernel/trace/trace_output.c
        kernel/tsacct.c
        mm/memcontrol.c
        mm/memory.c
        mm/mempolicy.c
        mm/migrate.c
        mm/mmu_notifier.c
        mm/nommu.c
        mm/util.c
      
        # mm_access():
        fs/proc/base.c
        include/linux/sched/mm.h
        kernel/fork.c
        mm/process_vm_access.c
      
        # mm_release():
        arch/arc/include/asm/mmu_context.h
        fs/exec.c
        include/linux/sched/mm.h
        include/uapi/linux/sched.h
        kernel/exit.c
        kernel/fork.c
      Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      68e21be2
  13. 02 3月, 2017 3 次提交
    • P
      sched/clock, x86/tsc: Rework the x86 'unstable' sched_clock() interface · f94c8d11
      Peter Zijlstra 提交于
      Wanpeng Li reported that since the following commit:
      
        acb04058 ("sched/clock: Fix hotplug crash")
      
      ... KVM always runs with unstable sched-clock even though KVM's
      kvm_clock _is_ stable.
      
      The problem is that we've tied clear_sched_clock_stable() to the TSC
      state, and overlooked that sched_clock() is a paravirt function.
      
      Solve this by doing two things:
      
       - tie the sched_clock() stable state more clearly to the TSC stable
         state for the normal (!paravirt) case.
      
       - only call clear_sched_clock_stable() when we mark TSC unstable
         when we use native_sched_clock().
      
      The first means we can actually run with stable sched_clock in more
      situations then before, which is good. And since commit:
      
        12907fbb ("sched/clock, clocksource: Add optional cs::mark_unstable() method")
      
      ... this should be reliable. Since any detection of TSC fail now results
      in marking the TSC unstable.
      Reported-by: NWanpeng Li <kernellwp@gmail.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Fixes: acb04058 ("sched/clock: Fix hotplug crash")
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      f94c8d11
    • I
      sched/headers: Prepare to move 'init_task' and 'init_thread_union' from... · 9164bb4a
      Ingo Molnar 提交于
      sched/headers: Prepare to move 'init_task' and 'init_thread_union' from <linux/sched.h> to <linux/sched/task.h>
      
      Update all usage sites first.
      Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      9164bb4a
    • I
      sched/headers: Prepare for new header dependencies before moving code to <linux/sched/clock.h> · e6017571
      Ingo Molnar 提交于
      We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which
      will have to be picked up from other headers and .c files.
      
      Create a trivial placeholder <linux/sched/clock.h> file that just
      maps to <linux/sched.h> to make this patch obviously correct and
      bisectable.
      
      Include the new header in the files that are going to need it.
      Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      e6017571
  14. 28 2月, 2017 1 次提交
  15. 05 2月, 2017 1 次提交
    • B
      x86/CPU/AMD: Bring back Compute Unit ID · 79a8b9aa
      Borislav Petkov 提交于
      Commit:
      
        a33d3317 ("x86/CPU/AMD: Fix Bulldozer topology")
      
      restored the initial approach we had with the Fam15h topology of
      enumerating CU (Compute Unit) threads as cores. And this is still
      correct - they're beefier than HT threads but still have some
      shared functionality.
      
      Our current approach has a problem with the Mad Max Steam game, for
      example. Yves Dionne reported a certain "choppiness" while playing on
      v4.9.5.
      
      That problem stems most likely from the fact that the CU threads share
      resources within one CU and when we schedule to a thread of a different
      compute unit, this incurs latency due to migrating the working set to a
      different CU through the caches.
      
      When the thread siblings mask mirrors that aspect of the CUs and
      threads, the scheduler pays attention to it and tries to schedule within
      one CU first. Which takes care of the latency, of course.
      Reported-by: NYves Dionne <yves.dionne@gmail.com>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Cc: <stable@vger.kernel.org> # 4.9
      Cc: Brice Goglin <Brice.Goglin@inria.fr>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Yazen Ghannam <yazen.ghannam@amd.com>
      Link: http://lkml.kernel.org/r/20170205105022.8705-1-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      79a8b9aa
  16. 04 2月, 2017 1 次提交
    • G
      x86/elf: Add HWCAP2 to expose ring 3 MONITOR/MWAIT · 0274f955
      Grzegorz Andrejczuk 提交于
      Introduce ELF_HWCAP2 variable for x86 and reserve its bit 0 to expose the
      ring 3 MONITOR/MWAIT.
      
      HWCAP variables contain bitmasks which can be used by userspace
      applications to detect which instruction sets are supported by CPU.  On x86
      architecture information about CPU capabilities can be checked via CPUID
      instructions, unfortunately presence of ring 3 MONITOR/MWAIT feature cannot
      be checked this way. ELF_HWCAP cannot be used as well, because on x86 it is
      set to CPUID[1].EDX which means that all bits are reserved there.
      
      HWCAP2 approach was chosen because it reuses existing solution present
      in other architectures, so only minor modifications are required to the
      kernel and userspace applications. When ELF_HWCAP2 is defined
      kernel maps it to AT_HWCAP2 during the start of the application.
      This way the ring 3 MONITOR/MWAIT feature can be detected using getauxval()
      API in a simple and fast manner. ELF_HWCAP2 type is u32 to be consistent
      with x86 ELF_HWCAP type.
      Signed-off-by: NGrzegorz Andrejczuk <grzegorz.andrejczuk@intel.com>
      Cc: Piotr.Luc@intel.com
      Cc: dave.hansen@linux.intel.com
      Link: http://lkml.kernel.org/r/1484918557-15481-3-git-send-email-grzegorz.andrejczuk@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      0274f955
  17. 25 1月, 2017 3 次提交
  18. 20 1月, 2017 1 次提交
    • P
      sched/clock: Fix hotplug crash · acb04058
      Peter Zijlstra 提交于
      Mike reported that he could trigger the WARN_ON_ONCE() in
      set_sched_clock_stable() using hotplug.
      
      This exposed a fundamental problem with the interface, we should never
      mark the TSC stable if we ever find it to be unstable. Therefore
      set_sched_clock_stable() is a broken interface.
      
      The reason it existed is that not having it is a pain, it means all
      relevant architecture code needs to call clear_sched_clock_stable()
      where appropriate.
      
      Of the three architectures that select HAVE_UNSTABLE_SCHED_CLOCK ia64
      and parisc are trivial in that they never called
      set_sched_clock_stable(), so add an unconditional call to
      clear_sched_clock_stable() to them.
      
      For x86 the story is a lot more involved, and what this patch tries to
      do is ensure we preserve the status quo. So even is Cyrix or Transmeta
      have usable TSC they never called set_sched_clock_stable() so they now
      get an explicit mark unstable.
      Reported-by: NMike Galbraith <efault@gmx.de>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Fixes: 9881b024 ("sched/clock: Delay switching sched_clock to stable")
      Link: http://lkml.kernel.org/r/20170119133633.GB6536@twins.programming.kicks-ass.netSigned-off-by: NIngo Molnar <mingo@kernel.org>
      acb04058
  19. 05 1月, 2017 1 次提交
  20. 19 12月, 2016 1 次提交
  21. 13 12月, 2016 1 次提交
    • T
      x86/smpboot: Make logical package management more robust · 9d85eb91
      Thomas Gleixner 提交于
      The logical package management has several issues:
      
       - The APIC ids provided by ACPI are not required to be the same as the
         initial APIC id which can be retrieved by CPUID. The APIC ids provided
         by ACPI are those which are written by the BIOS into the APIC. The
         initial id is set by hardware and can not be changed. The hardware
         provided ids contain the real hardware package information.
      
         Especially AMD sets the effective APIC id different from the hardware id
         as they need to reserve space for the IOAPIC ids starting at id 0.
      
         As a consequence those machines trigger the currently active firmware
         bug printouts in dmesg, These are obviously wrong.
      
       - Virtual machines have their own interesting of enumerating APICs and
         packages which are not reliably covered by the current implementation.
      
      The sizing of the mapping array has been tweaked to be generously large to
      handle systems which provide a wrong core count when HT is disabled so the
      whole magic which checks for space in the physical hotplug case is not
      needed anymore.
      
      Simplify the whole machinery and do the mapping when the CPU starts and the
      CPUID derived physical package information is available. This solves the
      observed problems on AMD machines and works for the virtualization issues
      as well.
      
      Remove the extra call from XEN cpu bringup code as it is not longer
      required.
      
      Fixes: d49597fd ("x86/cpu: Deal with broken firmware (VMWare/XEN)")
      Reported-and-tested-by: NBorislav Petkov <bp@suse.de>
      Tested-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: M. Vefa Bicakci <m.v.b@runbox.com>
      Cc: xen-devel <xen-devel@lists.xen.org>
      Cc: Charles (Chas) Williams <ciwillia@brocade.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Alok Kataria <akataria@vmware.com>
      Cc: stable@vger.kernel.org
      Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1612121102260.3429@nanosSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      9d85eb91
  22. 10 12月, 2016 1 次提交
  23. 10 11月, 2016 1 次提交
    • T
      x86/cpu: Deal with broken firmware (VMWare/XEN) · d49597fd
      Thomas Gleixner 提交于
      Both ACPI and MP specifications require that the APIC id in the respective
      tables must be the same as the APIC id in CPUID.
      
      The kernel retrieves the physical package id from the APIC id during the
      ACPI/MP table scan and builds the physical to logical package map. The
      physical package id which is used after a CPU comes up is retrieved from
      CPUID. So we rely on ACPI/MP tables and CPUID agreeing in that respect.
      
      There exist VMware and XEN implementations which violate the spec. As a
      result the physical to logical package map, which relies on the ACPI/MP
      tables does not work on those systems, because the CPUID initialized
      physical package id does not match the firmware id. This causes system
      crashes and malfunction due to invalid package mappings.
      
      The only way to cure this is to sanitize the physical package id after the
      CPUID enumeration and yell when the APIC ids are different. Fix up the
      initial APIC id, which is fine as it is only used printout purposes.
      
      If the physical package IDs differ yell and use the package information
      from the ACPI/MP tables so the existing logical package map just works.
      
      Chas provided the resulting dmesg output for his affected 4 virtual
      sockets, 1 core per socket VM:
      
      [Firmware Bug]: CPU1: APIC id mismatch. Firmware: 1 CPUID: 2
      [Firmware Bug]: CPU1: Using firmware package id 1 instead of 2
      ....
      
      Reported-and-tested-by: "Charles (Chas) Williams" <ciwillia@brocade.com>,
      Reported-by: NM. Vefa Bicakci <m.v.b@runbox.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Alok Kataria <akataria@vmware.com>
      Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
      Cc: #4.6+ <stable@vger,kernel.org>
      Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1611091613540.3501@nanosSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      d49597fd
  24. 25 10月, 2016 2 次提交
    • B
      x86/microcode: Run the AP-loading routine only on the application processors · 777284b6
      Borislav Petkov 提交于
      cpu_init() is run also on the BSP (in addition to the APs):
      
       x86_64_start_kernel
       |-> x86_64_start_reservations
       |-> start_kernel
       |-> trap_init
       |-> cpu_init
       |-> load_ucode_ap
       ...
      
      but we run the AP (Application Processors) microcode loading routine
      there too even though we have a BSP-specific routine for that:
      load_ucode_bsp().
      
      Which is unnecessary. So let's limit the AP microcode loading routine to
      the APs only.
      
      Remove a useless comment while at it.
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      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>
      Link: http://lkml.kernel.org/r/20161025095522.11964-2-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      777284b6
    • B
      x86/cpu: Get rid of the show_msr= boot option · 59c6f278
      Borislav Petkov 提交于
      It is useless as it dumps the MSRs too early BUT(!) we do set MSRs later too.
      Also, it dumps only BSP MSRs as it gets called only for CPU 0.
      
      And the MSR range array would need constant updating anyway, and so on
      and so on...
      
      Oh, and we have msr.ko and msr-tools which are the much better solution
      anyway. So off it goes...
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      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>
      Link: http://lkml.kernel.org/r/20161024173844.23038-4-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      59c6f278
  25. 30 9月, 2016 1 次提交
  26. 24 8月, 2016 1 次提交
  27. 19 8月, 2016 1 次提交
  28. 10 8月, 2016 1 次提交
    • K
      x86: Apply more __ro_after_init and const · 404f6aac
      Kees Cook 提交于
      Guided by grsecurity's analogous __read_only markings in arch/x86,
      this applies several uses of __ro_after_init to structures that are
      only updated during __init, and const for some structures that are
      never updated.  Additionally extends __init markings to some functions
      that are only used during __init, and cleans up some missing C99 style
      static initializers.
      Signed-off-by: NKees Cook <keescook@chromium.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brad Spengler <spender@grsecurity.net>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: David Brown <david.brown@linaro.org>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Emese Revfy <re.emese@gmail.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mathias Krause <minipli@googlemail.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: PaX Team <pageexec@freemail.hu>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: kernel-hardening@lists.openwall.com
      Link: http://lkml.kernel.org/r/20160808232906.GA29731@www.outflux.netSigned-off-by: NIngo Molnar <mingo@kernel.org>
      404f6aac
  29. 15 7月, 2016 1 次提交
  30. 14 7月, 2016 1 次提交
    • P
      x86/kernel: Audit and remove any unnecessary uses of module.h · 186f4360
      Paul Gortmaker 提交于
      Historically a lot of these existed because we did not have
      a distinction between what was modular code and what was providing
      support to modules via EXPORT_SYMBOL and friends.  That changed
      when we forked out support for the latter into the export.h file.
      
      This means we should be able to reduce the usage of module.h
      in code that is obj-y Makefile or bool Kconfig.  The advantage
      in doing so is that module.h itself sources about 15 other headers;
      adding significantly to what we feed cpp, and it can obscure what
      headers we are effectively using.
      
      Since module.h was the source for init.h (for __init) and for
      export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
      for the presence of either and replace as needed.  Build testing
      revealed some implicit header usage that was fixed up accordingly.
      
      Note that some bool/obj-y instances remain since module.h is
      the header for some exception table entry stuff, and for things
      like __init_or_module (code that is tossed when MODULES=n).
      Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/20160714001901.31603-4-paul.gortmaker@windriver.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      186f4360