Commit Graph

142 Commits

Author SHA1 Message Date
Borislav Petkov f7be8610bc x86/Documentation: Start documenting x86 topology
This should contain important aspects of how we represent the system
topology on x86. If people have questions about it and this file doesn't
answer it, then it must be updated.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20160328095609.GD26651@pd.tnic
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-29 10:45:04 +02:00
Linus Torvalds 24b5e20f11 Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The main changes are:

   - Use separate EFI page tables when executing EFI firmware code.
     This isolates the EFI context from the rest of the kernel, which
     has security and general robustness advantages.  (Matt Fleming)

   - Run regular UEFI firmware with interrupts enabled.  This is already
     the status quo under other OSs.  (Ard Biesheuvel)

   - Various x86 EFI enhancements, such as the use of non-executable
     attributes for EFI memory mappings.  (Sai Praneeth Prakhya)

   - Various arm64 UEFI enhancements.  (Ard Biesheuvel)

   - ... various fixes and cleanups.

  The separate EFI page tables feature got delayed twice already,
  because it's an intrusive change and we didn't feel confident about
  it - third time's the charm we hope!"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
  x86/mm/pat: Fix boot crash when 1GB pages are not supported by the CPU
  x86/efi: Only map kernel text for EFI mixed mode
  x86/efi: Map EFI_MEMORY_{XP,RO} memory region bits to EFI page tables
  x86/mm/pat: Don't implicitly allow _PAGE_RW in kernel_map_pages_in_pgd()
  efi/arm*: Perform hardware compatibility check
  efi/arm64: Check for h/w support before booting a >4 KB granular kernel
  efi/arm: Check for LPAE support before booting a LPAE kernel
  efi/arm-init: Use read-only early mappings
  efi/efistub: Prevent __init annotations from being used
  arm64/vmlinux.lds.S: Handle .init.rodata.xxx and .init.bss sections
  efi/arm64: Drop __init annotation from handle_kernel_image()
  x86/mm/pat: Use _PAGE_GLOBAL bit for EFI page table mappings
  efi/runtime-wrappers: Run UEFI Runtime Services with interrupts enabled
  efi: Reformat GUID tables to follow the format in UEFI spec
  efi: Add Persistent Memory type name
  efi: Add NV memory attribute
  x86/efi: Show actual ending addresses in efi_print_memmap
  x86/efi/bgrt: Don't ignore the BGRT if the 'valid' bit is 0
  efivars: Use to_efivar_entry
  efi: Runtime-wrapper: Get rid of the rtc_lock spinlock
  ...
2016-03-20 18:58:18 -07:00
Linus Torvalds 9cf8d6360c Merge branch 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 microcode updates from Ingo Molnar:
 "The biggest change in this cycle was the separation of the microcode
  loading mechanism from the initrd code plus the support of built-in
  microcode images.

  There were also lots cleanups and general restructuring (by Borislav
  Petkov)"

* 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/microcode/intel: Drop orig_sum from ext signature checksum
  x86/microcode/intel: Improve microcode sanity-checking error messages
  x86/microcode/intel: Merge two consecutive if-statements
  x86/microcode/intel: Get rid of DWSIZE
  x86/microcode/intel: Change checksum variables to u32
  x86/microcode: Use kmemdup() rather than duplicating its implementation
  x86/microcode: Remove unnecessary paravirt_enabled check
  x86/microcode: Document builtin microcode loading method
  x86/microcode/AMD: Issue microcode updated message later
  x86/microcode/intel: Cleanup get_matching_model_microcode()
  x86/microcode/intel: Remove unused arg of get_matching_model_microcode()
  x86/microcode/intel: Rename mc_saved_in_initrd
  x86/microcode/intel: Use *wrmsrl variants
  x86/microcode/intel: Cleanup apply_microcode_intel()
  x86/microcode/intel: Move the BUG_ON up and turn it into WARN_ON
  x86/microcode/intel: Rename mc_intel variable to mc
  x86/microcode/intel: Rename mc_saved_count to num_saved
  x86/microcode/intel: Rename local variables of type struct mc_saved_data
  x86/microcode/AMD: Drop redundant printk prefix
  x86/microcode: Issue update message only once
  ...
2016-03-15 10:39:22 -07:00
Linus Torvalds ba33ea811e Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:
 "This is another big update. Main changes are:

   - lots of x86 system call (and other traps/exceptions) entry code
     enhancements.  In particular the complex parts of the 64-bit entry
     code have been migrated to C code as well, and a number of dusty
     corners have been refreshed.  (Andy Lutomirski)

   - vDSO special mapping robustification and general cleanups (Andy
     Lutomirski)

   - cpufeature refactoring, cleanups and speedups (Borislav Petkov)

   - lots of other changes ..."

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits)
  x86/cpufeature: Enable new AVX-512 features
  x86/entry/traps: Show unhandled signal for i386 in do_trap()
  x86/entry: Call enter_from_user_mode() with IRQs off
  x86/entry/32: Change INT80 to be an interrupt gate
  x86/entry: Improve system call entry comments
  x86/entry: Remove TIF_SINGLESTEP entry work
  x86/entry/32: Add and check a stack canary for the SYSENTER stack
  x86/entry/32: Simplify and fix up the SYSENTER stack #DB/NMI fixup
  x86/entry: Only allocate space for tss_struct::SYSENTER_stack if needed
  x86/entry: Vastly simplify SYSENTER TF (single-step) handling
  x86/entry/traps: Clear DR6 early in do_debug() and improve the comment
  x86/entry/traps: Clear TIF_BLOCKSTEP on all debug exceptions
  x86/entry/32: Restore FLAGS on SYSEXIT
  x86/entry/32: Filter NT and speed up AC filtering in SYSENTER
  x86/entry/compat: In SYSENTER, sink AC clearing below the existing FLAGS test
  selftests/x86: In syscall_nt, test NT|TF as well
  x86/asm-offsets: Remove PARAVIRT_enabled
  x86/entry/32: Introduce and use X86_BUG_ESPFIX instead of paravirt_enabled
  uprobes: __create_xol_area() must nullify xol_mapping.fault
  x86/cpufeature: Create a new synthetic cpu capability for machine check recovery
  ...
2016-03-15 09:32:27 -07:00
Tony Luck 0f68c088c0 x86/cpufeature: Create a new synthetic cpu capability for machine check recovery
The Intel Software Developer Manual describes bit 24 in the MCG_CAP
MSR:

   MCG_SER_P (software error recovery support present) flag,
   bit 24 — Indicates (when set) that the processor supports
   software error recovery

But only some models with this capability bit set will actually
generate recoverable machine checks.

Check the model name and set a synthetic capability bit. Provide
a command line option to set this bit anyway in case the kernel
doesn't recognise the model name.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Reviewed-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>
Link: http://lkml.kernel.org/r/2e5bfb23c89800a036fb8a45fa97a74bb16bc362.1455732970.git.tony.luck@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-18 09:28:47 +01:00
Tony Luck 548acf1923 x86/mm: Expand the exception table logic to allow new handling options
Huge amounts of help from  Andy Lutomirski and Borislav Petkov to
produce this. Andy provided the inspiration to add classes to the
exception table with a clever bit-squeezing trick, Boris pointed
out how much cleaner it would all be if we just had a new field.

Linus Torvalds blessed the expansion with:

  ' I'd rather not be clever in order to save just a tiny amount of space
    in the exception table, which isn't really criticial for anybody. '

The third field is another relative function pointer, this one to a
handler that executes the actions.

We start out with three handlers:

 1: Legacy - just jumps the to fixup IP
 2: Fault - provide the trap number in %ax to the fixup code
 3: Cleaned up legacy for the uaccess error hack

Signed-off-by: Tony Luck <tony.luck@intel.com>
Reviewed-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>
Link: http://lkml.kernel.org/r/f6af78fcbd348cf4939875cfda9c19689b5e50b8.1455732970.git.tony.luck@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-18 09:21:46 +01:00
Borislav Petkov b584303261 x86/microcode: Document builtin microcode loading method
Add some text and an example to Documentation/x86/early-microcode.txt
explaining how to build in microcode.

Tested-by: Thomas Voegtle <tv@lio96.de>
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>
Link: http://lkml.kernel.org/r/1454499225-21544-18-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-09 11:41:19 +01:00
Matt Fleming ff3d0a12fb Documentation/x86: Update EFI memory region description
Make it clear that the EFI page tables are only available during
EFI runtime calls since that subject has come up a fair numbers
of times in the past.

Additionally, add the EFI region start and end addresses to the
table so that it's possible to see at a glance where they fall
in relation to other regions.

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Dave Jones <davej@codemonkey.org.uk>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1448658575-17029-7-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-29 09:15:43 +01:00
Linus Torvalds 25525bea46 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Ingo Molnar:
 "The dominant change in this cycle was the continued work to isolate
  kernel drivers from MTRR legacies: this tree gets rid of all kernel
  internal driver interfaces to MTRRs (mostly by rewriting it to proper
  PAT interfaces), the only access left is the /proc/mtrr ABI.

  This work was done by Luis R Rodriguez.

  There's also some related PCI interface additions for which I've
  Cc:-ed Bjorn"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  x86/mm/mtrr: Remove kernel internal MTRR interfaces: unexport mtrr_add() and mtrr_del()
  s390/io: Add pci_iomap_wc() and pci_iomap_wc_range()
  drivers/dma/iop-adma: Use dma_alloc_writecombine() kernel-style
  drivers/video/fbdev/vt8623fb: Use arch_phys_wc_add() and pci_iomap_wc()
  drivers/video/fbdev/s3fb: Use arch_phys_wc_add() and pci_iomap_wc()
  drivers/video/fbdev/arkfb.c: Use arch_phys_wc_add() and pci_iomap_wc()
  PCI: Add pci_iomap_wc() variants
  drivers/video/fbdev/gxt4500: Use pci_ioremap_wc_bar() to map framebuffer
  drivers/video/fbdev/kyrofb: Use arch_phys_wc_add() and pci_ioremap_wc_bar()
  drivers/video/fbdev/i740fb: Use arch_phys_wc_add() and pci_ioremap_wc_bar()
  PCI: Add pci_ioremap_wc_bar()
  x86/mm: Make kernel/check.c explicitly non-modular
  x86/mm/pat: Make mm/pageattr[-test].c explicitly non-modular
  x86/mm/pat: Add comments to cachemode translation tables
  arch/*/io.h: Add ioremap_uc() to all architectures
  drivers/video/fbdev/atyfb: Use arch_phys_wc_add() and ioremap_wc()
  drivers/video/fbdev/atyfb: Replace MTRR UC hole with strong UC
  drivers/video/fbdev/atyfb: Clarify ioremap() base and length used
  drivers/video/fbdev/atyfb: Carve out framebuffer length fudging into a helper
  x86/mm, asm-generic: Add IOMMU ioremap_uc() variant default
  ...
2015-09-01 10:07:40 -07:00
Linus Torvalds 11e612ddb4 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "The main x86 bootup related changes in this cycle were:

   - more boot time optimizations.  (Len Brown)

   - implement hex output to allow the debugging of early bootup
     parameters.  (Kees Cook)

   - remove obsolete MCA leftovers.  (Paolo Pisati)"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/smpboot: Remove APIC.wait_for_init_deassert and atomic init_deasserted
  x86/smpboot: Remove SIPI delays from cpu_up()
  x86/smpboot: Remove udelay(100) when polling cpu_callin_map
  x86/smpboot: Remove udelay(100) when polling cpu_initialized_map
  x86/boot: Obsolete the MCA sys_desc_table
  x86/boot: Add hex output for debugging
2015-09-01 09:04:31 -07:00
Luis R. Rodriguez 2baa891e42 x86/mm/mtrr: Remove kernel internal MTRR interfaces: unexport mtrr_add() and mtrr_del()
The effort to replace mtrr_add() with architecture agnostic
arch_phys_wc_add() is complete, this will ensure write-combining
implementations (PAT on x86) is taken advantage instead of using
MTRR. With the effort done now, hide direct MTRR access for
drivers.

The legacy user-space /proc/mtrr ABI is not affected.

Update x86 documentation on MTRR to reflect the completion of
the phasing out of direct access to MTRR, also add a note on
platform firmware code use of MTRRs based on the obituary
discussion of MTRRs on Linux [0].

  [0] http://lkml.kernel.org/r/1438991330.3109.196.camel@hp.com

Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Cc: <syrjala@sci.fi>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Walls <awalls@md.metrocast.net>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Doug Ledford <dledford@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Ville Syrjälä <syrjala@sci.fi>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: airlied@linux.ie
Cc: benh@kernel.crashing.org
Cc: bhelgaas@google.com
Cc: dan.j.williams@intel.com
Cc: konrad.wilk@oracle.com
Cc: linux-fbdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-media@vger.kernel.org
Cc: mst@redhat.com
Cc: netdev@vger.kernel.org
Cc: vinod.koul@intel.com
Cc: xen-devel@lists.xensource.com
Link: http://lkml.kernel.org/r/1440443613-13696-12-git-send-email-mcgrof@do-not-panic.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-28 10:09:28 +02:00
Alexander Kuleshov 0fe0965e63 Documentation/x86: Rename IRQSTACKSIZE to IRQ_STACK_SIZE
The IRQSTACKSIZE was renamed to the IRQ_STACK_SIZE in the
(26f80bd6a9 x86-64: Convert irqstacks to per-cpu) commit,
but it still named IRQSTACKSIZE in the documentation. This
patch fixes this.

Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-08-24 11:42:41 -06:00
Paolo Pisati 949163015c x86/boot: Obsolete the MCA sys_desc_table
The kernel does not support the MCA bus anymroe, so mark sys_desc_table
as obsolete: remove any reference from the code together with the remaining
of MCA logic.

bloat-o-meter output:

  add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-55 (-55)
  function                                     old     new   delta
  i386_start_kernel                            128     119      -9
  setup_arch                                  1421    1375     -46

Signed-off-by: Paolo Pisati <p.pisati@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
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/1437409430-8491-1-git-send-email-p.pisati@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-21 10:55:11 +02:00
James C Boyd 864d5bb957 x86/asm/entry/64: Update path names
The paths mentioned in this file weren't updated through some file
rename commits. Fix them to refer to the correct path.

Signed-off-by: James C Boyd <jcboyd.dev@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: corbet@lwn.net
Cc: trivial@kernel.org
Link: http://lkml.kernel.org/r/1435781606-3037-1-git-send-email-jcboyd.dev@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-02 11:08:50 +02:00
Ingo Molnar dc5fb575df Merge branch 'x86/boot' into x86/urgent
Merge branch that got ready.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-30 07:57:04 +02:00
Linus Torvalds d70b3ef54c Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 core updates from Ingo Molnar:
 "There were so many changes in the x86/asm, x86/apic and x86/mm topics
  in this cycle that the topical separation of -tip broke down somewhat -
  so the result is a more traditional architecture pull request,
  collected into the 'x86/core' topic.

  The topics were still maintained separately as far as possible, so
  bisectability and conceptual separation should still be pretty good -
  but there were a handful of merge points to avoid excessive
  dependencies (and conflicts) that would have been poorly tested in the
  end.

  The next cycle will hopefully be much more quiet (or at least will
  have fewer dependencies).

  The main changes in this cycle were:

   * x86/apic changes, with related IRQ core changes: (Jiang Liu, Thomas
     Gleixner)

     - This is the second and most intrusive part of changes to the x86
       interrupt handling - full conversion to hierarchical interrupt
       domains:

          [IOAPIC domain]   -----
                                 |
          [MSI domain]      --------[Remapping domain] ----- [ Vector domain ]
                                 |   (optional)          |
          [HPET MSI domain] -----                        |
                                                         |
          [DMAR domain]     -----------------------------
                                                         |
          [Legacy domain]   -----------------------------

       This now reflects the actual hardware and allowed us to distangle
       the domain specific code from the underlying parent domain, which
       can be optional in the case of interrupt remapping.  It's a clear
       separation of functionality and removes quite some duct tape
       constructs which plugged the remap code between ioapic/msi/hpet
       and the vector management.

     - Intel IOMMU IRQ remapping enhancements, to allow direct interrupt
       injection into guests (Feng Wu)

   * x86/asm changes:

     - Tons of cleanups and small speedups, micro-optimizations.  This
       is in preparation to move a good chunk of the low level entry
       code from assembly to C code (Denys Vlasenko, Andy Lutomirski,
       Brian Gerst)

     - Moved all system entry related code to a new home under
       arch/x86/entry/ (Ingo Molnar)

     - Removal of the fragile and ugly CFI dwarf debuginfo annotations.
       Conversion to C will reintroduce many of them - but meanwhile
       they are only getting in the way, and the upstream kernel does
       not rely on them (Ingo Molnar)

     - NOP handling refinements. (Borislav Petkov)

   * x86/mm changes:

     - Big PAT and MTRR rework: making the code more robust and
       preparing to phase out exposing direct MTRR interfaces to drivers -
       in favor of using PAT driven interfaces (Toshi Kani, Luis R
       Rodriguez, Borislav Petkov)

     - New ioremap_wt()/set_memory_wt() interfaces to support
       Write-Through cached memory mappings.  This is especially
       important for good performance on NVDIMM hardware (Toshi Kani)

   * x86/ras changes:

     - Add support for deferred errors on AMD (Aravind Gopalakrishnan)

       This is an important RAS feature which adds hardware support for
       poisoned data.  That means roughly that the hardware marks data
       which it has detected as corrupted but wasn't able to correct, as
       poisoned data and raises an APIC interrupt to signal that in the
       form of a deferred error.  It is the OS's responsibility then to
       take proper recovery action and thus prolonge system lifetime as
       far as possible.

     - Add support for Intel "Local MCE"s: upcoming CPUs will support
       CPU-local MCE interrupts, as opposed to the traditional system-
       wide broadcasted MCE interrupts (Ashok Raj)

     - Misc cleanups (Borislav Petkov)

   * x86/platform changes:

     - Intel Atom SoC updates

  ... and lots of other cleanups, fixlets and other changes - see the
  shortlog and the Git log for details"

* 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (222 commits)
  x86/hpet: Use proper hpet device number for MSI allocation
  x86/hpet: Check for irq==0 when allocating hpet MSI interrupts
  x86/mm/pat, drivers/infiniband/ipath: Use arch_phys_wc_add() and require PAT disabled
  x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled
  x86/platform/intel/baytrail: Add comments about why we disabled HPET on Baytrail
  genirq: Prevent crash in irq_move_irq()
  genirq: Enhance irq_data_to_desc() to support hierarchy irqdomain
  iommu, x86: Properly handle posted interrupts for IOMMU hotplug
  iommu, x86: Provide irq_remapping_cap() interface
  iommu, x86: Setup Posted-Interrupts capability for Intel iommu
  iommu, x86: Add cap_pi_support() to detect VT-d PI capability
  iommu, x86: Avoid migrating VT-d posted interrupts
  iommu, x86: Save the mode (posted or remapped) of an IRTE
  iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip
  iommu: dmar: Provide helper to copy shared irte fields
  iommu: dmar: Extend struct irte for VT-d Posted-Interrupts
  iommu: Add new member capability to struct irq_remap_ops
  x86/asm/entry/64: Disentangle error_entry/exit gsbase/ebx/usermode code
  x86/asm/entry/32: Shorten __audit_syscall_entry() args preparation
  x86/asm/entry/32: Explain reloading of registers after __audit_syscall_entry()
  ...
2015-06-22 17:59:09 -07:00
Linus Torvalds cfe3eceb7a Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 EFI updates from Ingo Molnar:
 "EFI changes:

   - Use idiomatic negative error values in efivar_create_sysfs_entry()
     instead of returning '1' to indicate error (Dan Carpenter)

   - Implement new support to expose the EFI System Resource Tables in
     sysfs, which provides information for performing firmware updates
     (Peter Jones)

   - Documentation cleanup in the EFI handover protocol section which
     falsely claimed that 'cmdline_size' needed to be filled out by the
     boot loader (Alex Smith)

   - Align the order of SMBIOS tables in /sys/firmware/efi/systab to
     match the way that we do things for ACPI and add documentation to
     Documentation/ABI (Jean Delvare)"

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi: Work around ia64 build problem with ESRT driver
  efi: Add 'systab' information to Documentation/ABI
  efi: dmi: List SMBIOS3 table before SMBIOS table
  efi/esrt: Fix some compiler warnings
  x86, doc: Remove cmdline_size from list of fields to be filled in for EFI handover
  efi: Add esrt support
  efi: efivar_create_sysfs_entry() should return negative error codes
2015-06-22 17:10:44 -07:00
Ingo Molnar 7ef3d7d58d Merge branches 'x86/apic', 'x86/asm', 'x86/mm' and 'x86/platform' into x86/core, to merge last updates
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-22 09:15:03 +02:00
Ingo Molnar 9dda1658a9 Merge branch 'x86/asm' into x86/core, to prepare for new patch
Collect all changes to arch/x86/entry/entry_64.S, before applying
patch that changes most of the file.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-08 20:48:20 +02:00
Ingo Molnar 2cd23553b4 x86/asm/entry: Rename compat syscall entry points
Rename the following system call entry points:

	ia32_cstar_target       -> entry_SYSCALL_compat
	ia32_syscall            -> entry_INT80_compat

The generic naming scheme for x86 system call entry points is:

	entry_MNEMONIC_qualifier

where 'qualifier' is one of _32, _64 or _compat.

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: 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>
2015-06-08 08:47:36 +02:00
Ingo Molnar c2f9b0af8b Merge branch 'x86/ras' into x86/core, to fix conflicts
Conflicts:
	arch/x86/include/asm/irq_vectors.h

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-07 15:35:27 +02:00
Ashok Raj 88d538672e x86/mce: Add infrastructure to support Local MCE
Initialize and prepare for handling LMCEs. Add a boot-time
option to disable LMCEs.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
[ Simplify stuff, align statements for better readability, reflow comments; kill
  unused lmce_clear(); save us an MSR write if LMCE is already enabled. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
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: Tony Luck <tony.luck@intel.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1433436928-31903-16-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-07 15:33:14 +02:00
Toshi Kani 623dffb2a2 x86/mm/pat: Add set_memory_wt() for Write-Through type
Now that reserve_ram_pages_type() accepts the WT type, add
set_memory_wt(), set_memory_array_wt() and set_pages_array_wt()
in order to be able to set memory to Write-Through page cache
mode.

Also, extend ioremap_change_attr() to accept the WT type.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Elliott@hp.com
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: arnd@arndb.de
Cc: hch@lst.de
Cc: hmh@hmh.eng.br
Cc: jgross@suse.com
Cc: konrad.wilk@oracle.com
Cc: linux-mm <linux-mm@kvack.org>
Cc: linux-nvdimm@lists.01.org
Cc: stefan.bader@canonical.com
Cc: yigal@plexistor.com
Link: http://lkml.kernel.org/r/1433436928-31903-13-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-07 15:29:00 +02:00
Toshi Kani d838270e25 x86/mm, asm-generic: Add ioremap_wt() for creating Write-Through mappings
Add ioremap_wt() for creating Write-Through mappings on x86. It
follows the same model as ioremap_wc() for multi-arch support.
Define ARCH_HAS_IOREMAP_WT in the x86 version of io.h to
indicate that ioremap_wt() is implemented on x86.

Also update the PAT documentation file to cover ioremap_wt().

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Elliott@hp.com
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: arnd@arndb.de
Cc: hch@lst.de
Cc: hmh@hmh.eng.br
Cc: jgross@suse.com
Cc: konrad.wilk@oracle.com
Cc: linux-mm <linux-mm@kvack.org>
Cc: linux-nvdimm@lists.01.org
Cc: stefan.bader@canonical.com
Cc: yigal@plexistor.com
Link: http://lkml.kernel.org/r/1433436928-31903-8-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-07 15:28:56 +02:00
Luis R. Rodriguez 2f9e897353 x86/mm/mtrr, pat: Document Write Combining MTRR type effects on PAT / non-PAT pages
As part of the effort to phase out MTRR use document
write-combining MTRR effects on pages with different non-PAT
page attributes flags and different PAT entry values. Extend
arch_phys_wc_add() documentation to clarify power of two sizes /
boundary requirements as we phase out mtrr_add() use.

Lastly hint towards ioremap_uc() for corner cases on device
drivers working with devices with mixed regions where MTRR size
requirements would otherwise not enable write-combining
effective memory types.

Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suresh Siddha <sbsiddha@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Ville Syrjälä <syrjala@sci.fi>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: linux-fbdev@vger.kernel.org
Link: http://lkml.kernel.org/r/1430343851-967-3-git-send-email-mcgrof@do-not-panic.com
Link: http://lkml.kernel.org/r/1432628901-18044-10-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-27 14:40:59 +02:00
Borislav Petkov 113b5e3720 x86/Documentation: Adapt Ingo's explanation on printing backtraces
Hold it down for future reference, as the question about the
question mark in stack traces keeps popping up.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Michal Marek <mmarek@suse.cz>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/1432628901-18044-18-git-send-email-bp@alien8.de
Link: http://lkml.kernel.org/r/20150521101614.GA10889@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-27 14:39:47 +02:00
Borislav Petkov d724a9a52b x86/Documentation: Remove STACKFAULT_STACK bulletpoint
Update the documentation after

  6f442be2fb ("x86_64, traps: Stop using IST for #SS").

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Michal Marek <mmarek@suse.cz>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/1432628901-18044-17-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-27 14:39:46 +02:00
Borislav Petkov 54fd157805 x86/Documentation: Move kernel-stacks doc one level up
... to Documentation/x86/ as it is going to collect more and not
only 64-bit specific info.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Michal Marek <mmarek@suse.cz>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/1432628901-18044-16-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-27 14:39:44 +02:00
Miroslav Benes d4bd441532 x86/kaslr: Fix typo in the KASLR_FLAG documentation
Documentation/x86/boot.txt labels the bit in
boot_params.hdr.loadflags as ALSR_FLAG while it should be
KASLR_FLAG.

Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
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: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
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/1429011324-7170-1-git-send-email-mbenes@suse.cz
Link: http://lkml.kernel.org/r/1431332153-18566-4-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-11 10:28:57 +02:00
Alex Smith a93e178838 x86, doc: Remove cmdline_size from list of fields to be filled in for EFI handover
The cmdline_size field in setup_header is listed as read-only, and is
never read by the kernel. Therefore, there is no need for it to be set
by a boot loader implementing the EFI handover protocol, so remove it
from the list of fields required to be set by a boot loader.

Signed-off-by: Alex Smith <alex@alex-smith.me.uk>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-04-30 22:15:05 +01:00
Borislav Petkov 78cac48c04 x86/mm/KASLR: Propagate KASLR status to kernel proper
Commit:

  e2b32e6785 ("x86, kaslr: randomize module base load address")

made module base address randomization unconditional and didn't regard
disabled KKASLR due to CONFIG_HIBERNATION and command line option
"nokaslr". For more info see (now reverted) commit:

  f47233c2d3 ("x86/mm/ASLR: Propagate base load address calculation")

In order to propagate KASLR status to kernel proper, we need a single bit
in boot_params.hdr.loadflags and we've chosen bit 1 thus leaving the
top-down allocated bits for bits supposed to be used by the bootloader.

Originally-From: Jiri Kosina <jkosina@suse.cz>
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-03 15:26:15 +02:00
Linus Torvalds 5fbe4c224c Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc x86 fixes from Ingo Molnar:
 "This contains:

   - EFI fixes
   - a boot printout fix
   - ASLR/kASLR fixes
   - intel microcode driver fixes
   - other misc fixes

  Most of the linecount comes from an EFI revert"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/ASLR: Avoid PAGE_SIZE redefinition for UML subarch
  x86/microcode/intel: Handle truncated microcode images more robustly
  x86/microcode/intel: Guard against stack overflow in the loader
  x86, mm/ASLR: Fix stack randomization on 64-bit systems
  x86/mm/init: Fix incorrect page size in init_memory_mapping() printks
  x86/mm/ASLR: Propagate base load address calculation
  Documentation/x86: Fix path in zero-page.txt
  x86/apic: Fix the devicetree build in certain configs
  Revert "efi/libstub: Call get_memory_map() to obtain map and desc sizes"
  x86/efi: Avoid triple faults during EFI mixed mode calls
2015-02-21 10:41:29 -08:00
Alexander Kuleshov f5ecb00569 Documentation/x86: Fix path in zero-page.txt
Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Cc: Martin Mares <mj@ucw.cz>
Link: http://lkml.kernel.org/r/1422689004-13318-1-git-send-email-kuleshovmail@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-18 23:04:00 +01:00
Andrey Ryabinin ef7f0d6a6c x86_64: add KASan support
This patch adds arch specific code for kernel address sanitizer.

16TB of virtual addressed used for shadow memory.  It's located in range
[ffffec0000000000 - fffffc0000000000] between vmemmap and %esp fixup
stacks.

At early stage we map whole shadow region with zero page.  Latter, after
pages mapped to direct mapping address range we unmap zero pages from
corresponding shadow (see kasan_map_shadow()) and allocate and map a real
shadow memory reusing vmemmap_populate() function.

Also replace __pa with __pa_nodebug before shadow initialized.  __pa with
CONFIG_DEBUG_VIRTUAL=y make external function call (__phys_addr)
__phys_addr is instrumented, so __asan_load could be called before shadow
area initialized.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:41 -08:00
Andy Lutomirski 48e08d0fb2 x86, entry: Switch stacks on a paranoid entry from userspace
This causes all non-NMI, non-double-fault kernel entries from
userspace to run on the normal kernel stack.  Double-fault is
exempt to minimize confusion if we double-fault directly from
userspace due to a bad kernel stack.

This is, suprisingly, simpler and shorter than the current code.  It
removes the IMO rather frightening paranoid_userspace path, and it
make sync_regs much simpler.

There is no risk of stack overflow due to this change -- the kernel
stack that we switch to is empty.

This will also enable us to create non-atomic sections within
machine checks from userspace, which will simplify memory failure
handling.  It will also allow the upcoming fsgsbase code to be
simplified, because it doesn't need to worry about usergs when
scheduling in paranoid_exit, as that code no longer exists.

Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Tony Luck <tony.luck@intel.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
2015-01-02 10:22:45 -08:00
Linus Torvalds a54455766b Merge branch 'x86-mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 MPX fixes from Thomas Gleixner:
 "Three updates for the new MPX infrastructure:
   - Use the proper error check in the trap handler
   - Add a proper config option for it
   - Bring documentation up to date"

* 'x86-mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, mpx: Give MPX a real config option prompt
  x86, mpx: Update documentation
  x86_64/traps: Fix always true condition
2014-12-19 13:22:42 -08:00
Dave Hansen 72e9b5fe9b x86, mpx: Give MPX a real config option prompt
Give MPX a real config option. The CPUs that support it (referenced
here):

  https://software.intel.com/en-us/forums/topic/402393

are not available publicly yet. Right now only the software emulator
provides MPX for the general public.

[ tglx: Make it default off. There is no point in having it on right
        now as no hardware and no proper tooling support are available ]

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141212183836.2569D58D@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-15 15:58:57 +01:00
Dave Hansen 010e593b14 x86, mpx: Update documentation
I was writing some MPX test programs and realized that the
current design makes it tricky.  I did something like:

	bndcfgu |= bnd_dir | BNDCFGU_ENABLE;
	xrstor();
	printf("xrstor done");
	// #BR bounds exception here
	prctl(MPX_ENABLE_MANAGEMENT);

and then compiled the app with "-fcheck-pointer-bounds -mmpx"
to enable MPX instrumentation.

The problem is that there is MPX instrumentation inserted in
to the area of the printf().  The kernel gets a bounds exception
and since management isn't yet enabled, it SIGSEGV's.

Add a bit to the documentation to explain a way around this and
where apps need to be careful.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141212183835.8C581B3E@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-15 15:58:57 +01:00
Linus Torvalds 536e89ee53 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes (mainly Andy's TLS fixes), plus a cleanup"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/tls: Disallow unusual TLS segments
  x86/tls: Validate TLS entries to protect espfix
  MAINTAINERS: Add me as x86 VDSO submaintainer
  x86/asm: Unify segment selector defines
  x86/asm: Guard against building the 32/64-bit versions of the asm-offsets*.c file directly
  x86_64, switch_to(): Load TLS descriptors before switching DS and ES
  x86/mm: Use min() instead of min_t() in the e820 printout code
  x86/mm: Fix zone ranges boot printout
  x86/doc: Update documentation after file shuffling
2014-12-14 11:51:50 -08:00
Luis R. Rodriguez 96ed4cd0aa x86/doc: Update documentation after file shuffling
While at it, also refer to the 32 bit entry file.

Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: linux-doc@vger.kernel.org
Cc: bpoirier@suse.de
Link: http://lkml.kernel.org/r/1418165684-6226-1-git-send-email-mcgrof@do-not-panic.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-12-11 11:33:22 +01:00
Qiaowei Ren 5776563648 x86, mpx: Add documentation on Intel MPX
This patch adds the Documentation/x86/intel_mpx.txt file with some
information about Intel MPX.

Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151832.7FDB1720@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-18 00:58:54 +01:00
Dave Hansen beb9147e95 x86/mm: Update memory map description to list hypervisor-reserved area
Peter Anvin says:

 > 0xffff880000000000 is the lowest usable address because we have
 > agreed to leave 0xffff800000000000-0xffff880000000000 for the
 > hypervisor or other non-OS uses.

Let's call this out in the documentation.

This came up during the kernel address sanitizer discussions
where it was proposed to use this area for other kernel things.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Link: http://lkml.kernel.org/r/20140918195606.841389D2@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-19 12:48:02 +02:00
Jeremiah Mahler 129ea00594 x86/doc: Fix the 'tlb_single_page_flush_ceiling' sysconfig path
Fix the documented sysconfig location of 'tlb_single_page_flush_ceiling'
which is under /sys/kernel/debug/... not /sys/debug/kernel/...

Signed-off-by: Jeremiah Mahler <jmmahler@gmail.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Link: http://lkml.kernel.org/r/1407484195-1441-1-git-send-email-jmmahler@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-10 09:09:26 +02:00
Dave Hansen 2d040a1ce9 x86/mm: New tunable for single vs full TLB flush
Most of the logic here is in the documentation file.  Please take
a look at it.

I know we've come full-circle here back to a tunable, but this
new one is *WAY* simpler.  I challenge anyone to describe in one
sentence how the old one worked.  Here's the way the new one
works:

	If we are flushing more pages than the ceiling, we use
	the full flush, otherwise we use per-page flushes.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: http://lkml.kernel.org/r/20140731154101.12B52CAF@viggo.jf.intel.com
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-07-31 08:48:51 -07:00
Linus Torvalds 2071b3e34f Merge branch 'x86/espfix' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next
Pull x86-64 espfix changes from Peter Anvin:
 "This is the espfix64 code, which fixes the IRET information leak as
  well as the associated functionality problem.  With this code applied,
  16-bit stack segments finally work as intended even on a 64-bit
  kernel.

  Consequently, this patchset also removes the runtime option that we
  added as an interim measure.

  To help the people working on Linux kernels for very small systems,
  this patchset also makes these compile-time configurable features"

* 'x86/espfix' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "x86-64, modify_ldt: Make support for 16-bit segments a runtime option"
  x86, espfix: Make it possible to disable 16-bit support
  x86, espfix: Make espfix64 a Kconfig option, fix UML
  x86, espfix: Fix broken header guard
  x86, espfix: Move espfix definitions into a separate header file
  x86-32, espfix: Remove filter for espfix32 due to race
  x86-64, espfix: Don't leak bits 31:16 of %esp returning to 16-bit stack
2014-06-05 07:46:15 -07:00
Carlos Garcia c98be0c96d doc: spelling error changes
Fixed multiple spelling errors.

Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Carlos E. Garcia <carlos@cgarcia.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-05-05 15:32:05 +02:00
H. Peter Anvin 3891a04aaf x86-64, espfix: Don't leak bits 31:16 of %esp returning to 16-bit stack
The IRET instruction, when returning to a 16-bit segment, only
restores the bottom 16 bits of the user space stack pointer.  This
causes some 16-bit software to break, but it also leaks kernel state
to user space.  We have a software workaround for that ("espfix") for
the 32-bit kernel, but it relies on a nonzero stack segment base which
is not available in 64-bit mode.

In checkin:

    b3b42ac2cb x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels

we "solved" this by forbidding 16-bit segments on 64-bit kernels, with
the logic that 16-bit support is crippled on 64-bit kernels anyway (no
V86 support), but it turns out that people are doing stuff like
running old Win16 binaries under Wine and expect it to work.

This works around this by creating percpu "ministacks", each of which
is mapped 2^16 times 64K apart.  When we detect that the return SS is
on the LDT, we copy the IRET frame to the ministack and use the
relevant alias to return to userspace.  The ministacks are mapped
readonly, so if IRET faults we promote #GP to #DF which is an IST
vector and thus has its own stack; we then do the fixup in the #DF
handler.

(Making #GP an IST exception would make the msr_safe functions unsafe
in NMI/MC context, and quite possibly have other effects.)

Special thanks to:

- Andy Lutomirski, for the suggestion of using very small stack slots
  and copy (as opposed to map) the IRET frame there, and for the
  suggestion to mark them readonly and let the fault promote to #DF.
- Konrad Wilk for paravirt fixup and testing.
- Borislav Petkov for testing help and useful comments.

Reported-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1398816946-3351-1-git-send-email-hpa@linux.intel.com
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andrew Lutomriski <amluto@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dirk Hohndel <dirk@hohndel.org>
Cc: Arjan van de Ven <arjan.van.de.ven@intel.com>
Cc: comex <comexk@gmail.com>
Cc: Alexander van Heukelum <heukelum@fastmail.fm>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: <stable@vger.kernel.org> # consider after upstream merge
2014-04-30 14:14:28 -07:00
Borislav Petkov 3e920b532a x86, boot: Correct max ramdisk size name
The name in struct bootparam is ->initrd_addr_max and not ramdisk_max.
Fix that.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1394633584-5509-2-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-13 15:32:42 -07:00
Henrik Austad 3cf8ca1c25 Documentation/: update 00-INDEX files
Some of the 00-INDEX files are somewhat outdated and some folders does
not contain 00-INDEX at all.  Only outdated (with the notably exception
of spi) indexes are touched here, the 169 folders without 00-INDEX has
not been touched.

New 00-INDEX
 - spi/* was added in a series of commits dating back to 2006

Added files (missing in (*/)00-INDEX)
 - dmatest.txt was added by commit 851b7e16a0 ("dmatest: run test via
   debugfs")
 - this_cpu_ops.txt was added by commit a1b2a555d6 ("percpu: add
   documentation on this_cpu operations")
 - ww-mutex-design.txt was added by commit 040a0a3710 ("mutex: Add
   support for wound/wait style locks")
 - bcache.txt was added by commit cafe563591 ("bcache: A block layer
   cache")
 - kernel-per-CPU-kthreads.txt was added by commit 49717cb404
   ("kthread: Document ways of reducing OS jitter due to per-CPU
   kthreads")
 - phy.txt was added by commit ff76496347 ("drivers: phy: add generic
   PHY framework")
 - block/null_blk was added by commit 12f8f4fc03 ("null_blk:
   documentation")
 - module-signing.txt was added by commit 3cafea3076 ("Add
   Documentation/module-signing.txt file")
 - assoc_array.txt was added by commit 3cb989501c ("Add a generic
   associative array implementation.")
 - arm/IXP4xx was part of the initial repo
 - arm/cluster-pm-race-avoidance.txt was added by commit 7fe31d28e8
   ("ARM: mcpm: introduce helpers for platform coherency exit/setup")
 - arm/firmware.txt was added by commit 7366b92a77 ("ARM: Add
   interface for registering and calling firmware-specific operations")
 - arm/kernel_mode_neon.txt was added by commit 2afd0a0524 ("ARM:
   7825/1: document the use of NEON in kernel mode")
 - arm/tcm.txt was added by commit bc581770cf ("ARM: 5580/2: ARM TCM
   (Tightly-Coupled Memory) support v3")
 - arm/vlocks.txt was added by commit 9762f12d3e ("ARM: mcpm: Add
   baremetal voting mutexes")
 - blackfin/gptimers-example.c, Makefile was added by commit
   4b60779d5e ("Blackfin: add an example showing how to use the
   gptimers API")
 - devicetree/usage-model.txt was added by commit 31134efc68 ("dt:
   Linux DT usage model documentation")
 - fb/api.txt was added by commit fb21c2f428 ("fbdev: Add FOURCC-based
   format configuration API")
 - fb/sm501.txt was added by commit e6a0498071 ("video, sm501: add
   edid and commandline support")
 - fb/udlfb.txt was added by commit 96f8d864af ("fbdev: move udlfb out
   of staging.")
 - filesystems/Makefile was added by commit 1e0051ae48
   ("Documentation/fs/: split txt and source files")
 - filesystems/nfs/nfsd-admin-interfaces.txt was added by commit
   8a4c6e19cf ("nfsd: document kernel interfaces for nfsd
   configuration")
 - ide/warm-plug-howto.txt was added by commit f74c91413e ("ide: add
   warm-plug support for IDE devices (take 2)")
 - laptops/Makefile was added by commit d49129accc
   ("Documentation/laptop/: split txt and source files")
 - leds/leds-blinkm.txt was added by commit b54cf35a7f ("LEDS: add
   BlinkM RGB LED driver, documentation and update MAINTAINERS")
 - leds/ledtrig-oneshot.txt was added by commit 5e417281cd ("leds: add
   oneshot trigger")
 - leds/ledtrig-transient.txt was added by commit 44e1e9f8e7 ("leds:
   add new transient trigger for one shot timer activation")
 - m68k/README.buddha was part of the initial repo
 - networking/LICENSE.(qla3xxx|qlcnic|qlge) was added by commits
   40839129f7, c4e84bde1d, 5a4faa8737
 - networking/Makefile was added by commit 3794f3e812 ("docsrc: build
   Documentation/ sources")
 - networking/i40evf.txt was added by commit 105bf2fe6b ("i40evf: add
   driver to kernel build system")
 - networking/ipsec.txt was added by commit b3c6efbc36 ("xfrm: Add
   file to document IPsec corner case")
 - networking/mac80211-auth-assoc-deauth.txt was added by commit
   3cd7920a2b ("mac80211: add auth/assoc/deauth flow diagram")
 - networking/netlink_mmap.txt was added by commit 5683264c39
   ("netlink: add documentation for memory mapped I/O")
 - networking/nf_conntrack-sysctl.txt was added by commit c9f9e0e159
   ("netfilter: doc: add nf_conntrack sysctl api documentation") lan)
 - networking/team.txt was added by commit 3d249d4ca7 ("net: introduce
   ethernet teaming device")
 - networking/vxlan.txt was added by commit d342894c5d ("vxlan:
   virtual extensible lan")
 - power/runtime_pm.txt was added by commit 5e928f77a0 ("PM: Introduce
   core framework for run-time PM of I/O devices (rev.  17)")
 - power/charger-manager.txt was added by commit 3bb3dbbd56
   ("power_supply: Add initial Charger-Manager driver")
 - RCU/lockdep-splat.txt was added by commit d7bd2d68aa ("rcu:
   Document interpretation of RCU-lockdep splats")
 - s390/kvm.txt was added by 5ecee4b (KVM: s390: API documentation)
 - s390/qeth.txt was added by commit b4d72c08b3 ("qeth: bridgeport
   support - basic control")
 - scheduler/sched-bwc.txt was added by commit 88ebc08ea9 ("sched: Add
   documentation for bandwidth control")
 - scsi/advansys.txt was added by commit 4bd6d7f356 ("[SCSI] advansys:
   Move documentation to Documentation/scsi")
 - scsi/bfa.txt was added by commit 1ec90174bd ("[SCSI] bfa: add
   readme file")
 - scsi/bnx2fc.txt was added by commit 12b8fc10ea ("[SCSI] bnx2fc: Add
   driver documentation")
 - scsi/cxgb3i.txt was added by commit c3673464eb ("[SCSI] cxgb3i: Add
   cxgb3i iSCSI driver.")
 - scsi/hpsa.txt was added by commit 992ebcf14f ("[SCSI] hpsa: Add
   hpsa.txt to Documentation/scsi")
 - scsi/link_power_management_policy.txt was added by commit
   ca77329fb7 ("[libata] Link power management infrastructure")
 - scsi/osd.txt was added by commit 78e0c621de ("[SCSI] osd:
   Documentation for OSD library")
 - scsi/scsi-parameter.txt was created/moved by commit 163475fb11
   ("Documentation: move SCSI parameters to their own text file")
 - serial/driver was part of the initial repo
 - serial/n_gsm.txt was added by commit 323e84122e ("n_gsm: add a
   documentation")
 - timers/Makefile was added by commit 3794f3e812 ("docsrc: build
   Documentation/ sources")
 - virt/kvm/s390.txt was added by commit d9101fca3d ("KVM: s390:
   diagnose call documentation")
 - vm/split_page_table_lock was added by commit 49076ec2cc ("mm:
   dynamically allocate page->ptl if it cannot be embedded to struct
   page")
 - w1/slaves/w1_ds28e04 was added by commit fbf7f7b4e2 ("w1: Add
   1-wire slave device driver for DS28E04-100")
 - w1/masters/omap-hdq was added by commit e0a29382c6 ("hdq:
   documentation for OMAP HDQ")
 - x86/early-microcode.txt was added by commit 0d91ea86a8 ("x86, doc:
   Documentation for early microcode loading")
 - x86/earlyprintk.txt was added by commit a1aade4788 ("x86/doc:
   mini-howto for using earlyprintk=dbgp")
 - x86/entry_64.txt was added by commit 8b4777a4b5 ("x86-64: Document
   some of entry_64.S")
 - x86/pat.txt was added by commit d27554d874 ("x86: PAT
   documentation")

Moved files
 - arm/kernel_user_helpers.txt was moved out of arch/arm/kernel by
   commit 37b8304642 ("ARM: kuser: move interface documentation out of
   the source code")
 - efi-stub.txt was moved out of x86/ and down into Documentation/ in
   commit 4172fe2f8a ("EFI stub documentation updates")
 - laptops/hpfall.c was moved out of hwmon/ and into laptops/ in commit
   efcfed9bad ("Move hp_accel to drivers/platform/x86")
 - commit 5616c23ad9 ("x86: doc: move x86-generic documentation from
   Doc/x86/i386"):
   * x86/usb-legacy-support.txt
   * x86/boot.txt
   * x86/zero_page.txt
 - power/video_extension.txt was moved to acpi in commit 70e66e4df1
   ("ACPI / video: move video_extension.txt to Documentation/acpi")

Removed files (left in 00-INDEX)
 - memory.txt was removed by commit 00ea8990aa ("memory.txt: remove
   stray information")
 - gpio.txt was moved to gpio/ in commit fd8e198cfc ("Documentation:
   gpiolib: document new interface")
 - networking/DLINK.txt was removed by commit 168e06ae26
   ("drivers/net: delete old parallel port de600/de620 drivers")
 - serial/hayes-esp.txt was removed by commit f53a2ade0b ("tty: esp:
   remove broken driver")
 - s390/TAPE was removed by commit 9e280f6693 ("[S390] remove tape
   block docu")
 - vm/locking was removed by commit 57ea8171d2 ("mm: documentation:
   remove hopelessly out-of-date locking doc")
 - laptops/acer-wmi.txt was remvoed by commit 020036678e ("acer-wmi:
   Delete out-of-date documentation")

Typos/misc issues
 - rpc-server-gss.txt was added as knfsd-rpcgss.txt in commit
   030d794bf4 ("SUNRPC: Use gssproxy upcall for server RPCGSS
   authentication.")
 - commit b88cf73d92 ("net: add missing entries to
   Documentation/networking/00-INDEX")
   * generic-hdlc.txt was added as generic_hdlc.txt
   * spider_net.txt was added as spider-net.txt
 - w1/master/mxc-w1 was added as mxc_w1 by commit a5fd9139f7 ("w1: add
   1-wire master driver for i.MX27 / i.MX31")
 - s390/zfcpdump.txt was added as zfcpdump by commit 6920c12a40
   ("[S390] Add Documentation/s390/00-INDEX.")

Signed-off-by: Henrik Austad <henrik@austad.us>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>	[rcu bits]
Acked-by: Rob Landley <rob@landley.net>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Mark Brown <broonie@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Len Brown <len.brown@intel.com>
Cc: James Bottomley <JBottomley@parallels.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-02-10 16:01:40 -08:00
Linus Torvalds bb1281f2aa Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
 "Usual rocket science stuff from trivial.git"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits)
  neighbour.h: fix comment
  sched: Fix warning on make htmldocs caused by wait.h
  slab: struct kmem_cache is protected by slab_mutex
  doc: Fix typo in USB Gadget Documentation
  of/Kconfig: Spelling s/one/once/
  mkregtable: Fix sscanf handling
  lp5523, lp8501: comment improvements
  thermal: rcar: comment spelling
  treewide: fix comments and printk msgs
  IXP4xx: remove '1 &&' from a condition check in ixp4xx_restart()
  Documentation: update /proc/uptime field description
  Documentation: Fix size parameter for snprintf
  arm: fix comment header and macro name
  asm-generic: uaccess: Spelling s/a ny/any/
  mtd: onenand: fix comment header
  doc: driver-model/platform.txt: fix a typo
  drivers: fix typo in DEVTMPFS_MOUNT Kconfig help text
  doc: Fix typo (acces_process_vm -> access_process_vm)
  treewide: Fix typos in printk
  drivers/gpu/drm/qxl/Kconfig: reformat the help text
  ...
2014-01-22 21:21:55 -08:00