1. 13 4月, 2016 13 次提交
  2. 31 3月, 2016 5 次提交
  3. 29 3月, 2016 6 次提交
    • B
      x86/cpu: Do the feature test first in enable_sep_cpu() · b3edfda4
      Borislav Petkov 提交于
      ... before assigning local vars. Kill out label too and simplify.
      
      No functionality change.
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Acked-by: NAndy Lutomirski <luto@kernel.org>
      Cc: Andy Lutomirski <luto@amacapital.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/1458130769-24963-1-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      b3edfda4
    • T
      x86/mtrr: Fix PAT init handling when MTRR is disabled · ad025a73
      Toshi Kani 提交于
      get_mtrr_state() calls pat_init() on BSP even if MTRR is disabled.
      This results in calling pat_init() on BSP only since APs do not call
      pat_init() when MTRR is disabled.  This inconsistency between BSP
      and APs leads to undefined behavior.
      
      Make BSP's calling condition to pat_init() consistent with AP's,
      mtrr_ap_init() and mtrr_aps_init().
      Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
      Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Luis R. Rodriguez <mcgrof@suse.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Toshi Kani <toshi.kani@hp.com>
      Cc: elliott@hpe.com
      Cc: konrad.wilk@oracle.com
      Cc: paul.gortmaker@windriver.com
      Cc: xen-devel@lists.xenproject.org
      Link: http://lkml.kernel.org/r/1458769323-24491-6-git-send-email-toshi.kani@hpe.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      ad025a73
    • T
      x86/mtrr: Fix Xorg crashes in Qemu sessions · edfe63ec
      Toshi Kani 提交于
      A Xorg failure on qemu32 was reported as a regression [1] caused by
      commit 9cd25aac ("x86/mm/pat: Emulate PAT when it is disabled").
      
      This patch fixes the Xorg crash.
      
      Negative effects of this regression were the following two failures [2]
      in Xorg on QEMU with QEMU CPU model "qemu32" (-cpu qemu32), which were
      triggered by the fact that its virtual CPU does not support MTRRs.
      
       #1. copy_process() failed in the check in reserve_pfn_range()
      
          copy_process
           copy_mm
            dup_mm
             dup_mmap
              copy_page_range
               track_pfn_copy
                reserve_pfn_range
      
       A WC map request was tracked as WC in memtype, which set a PTE as
       UC (pgprot) per __cachemode2pte_tbl[].  This led to this error in
       reserve_pfn_range() called from track_pfn_copy(), which obtained
       a pgprot from a PTE.  It converts pgprot to page_cache_mode, which
       does not necessarily result in the original page_cache_mode since
       __cachemode2pte_tbl[] redirects multiple types to UC.
      
       #2. error path in copy_process() then hit WARN_ON_ONCE in
           untrack_pfn().
      
           x86/PAT: Xorg:509 map pfn expected mapping type uncached-
           minus for [mem 0xfd000000-0xfdffffff], got write-combining
            Call Trace:
           dump_stack
           warn_slowpath_common
           ? untrack_pfn
           ? untrack_pfn
           warn_slowpath_null
           untrack_pfn
           ? __kunmap_atomic
           unmap_single_vma
           ? pagevec_move_tail_fn
           unmap_vmas
           exit_mmap
           mmput
           copy_process.part.47
           _do_fork
           SyS_clone
           do_syscall_32_irqs_on
           entry_INT80_32
      
      These negative effects are caused by two separate bugs, but they
      can be addressed in separate patches.  Fixing the pat_init() issue
      described below addresses the root cause, and avoids Xorg to hit
      these cases.
      
      When the CPU does not support MTRRs, MTRR does not call pat_init(),
      which leaves PAT enabled without initializing PAT.  This pat_init()
      issue is a long-standing issue, but manifested as issue #1 (and then
      hit issue #2) with the above-mentioned commit because the memtype
      now tracks cache attribute with 'page_cache_mode'.
      
      This pat_init() issue existed before the commit, but we used pgprot
      in memtype.  Hence, we did not have issue #1 before.  But WC request
      resulted in WT in effect because WC pgrot is actually WT when PAT
      is not initialized.  This is not how it was designed to work.  When
      PAT is set to disable properly, WC is converted to UC.  The use of
      WT can result in a system crash if the target range does not support
      WT.  Fortunately, nobody ran into such issue before.
      
      To fix this pat_init() issue, PAT code has been enhanced to provide
      pat_disable() interface.  Call this interface when MTRRs are disabled.
      By setting PAT to disable properly, PAT bypasses the memtype check,
      and avoids issue #1.
      
        [1]: https://lkml.org/lkml/2016/3/3/828
        [2]: https://lkml.org/lkml/2016/3/4/775Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
      Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Luis R. Rodriguez <mcgrof@suse.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Toshi Kani <toshi.kani@hp.com>
      Cc: elliott@hpe.com
      Cc: konrad.wilk@oracle.com
      Cc: paul.gortmaker@windriver.com
      Cc: xen-devel@lists.xenproject.org
      Link: http://lkml.kernel.org/r/1458769323-24491-5-git-send-email-toshi.kani@hpe.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      edfe63ec
    • H
      x86/cpu: Add advanced power management bits · 34a4cceb
      Huang Rui 提交于
      Bit 11 of CPUID 8000_0007 edx is processor feedback interface.
      Bit 12 of CPUID 8000_0007 edx is accumulated power.
      
      Print proper names in proc/cpuinfo
      Reported-and-tested-by: NBorislav Petkov <bp@alien8.de>
      Signed-off-by: NHuang Rui <ray.huang@amd.com>
      Cc: Tony Li <tony.li@amd.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Fengguang Wu <fengguang.wu@intel.com>
      Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: "Len Brown" <lenb@kernel.org>
      Link: http://lkml.kernel.org/r/1458871720-3209-1-git-send-email-ray.huang@amd.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      34a4cceb
    • B
      8196dab4
    • P
      x86/topology: Fix AMD core count · ee6825c8
      Peter Zijlstra 提交于
      It turns out AMD gets x86_max_cores wrong when there are compute
      units.
      
      The issue is that Linux assumes:
      
      	nr_logical_cpus = nr_cores * nr_siblings
      
      But AMD reports its CU unit as 2 cores, but then sets num_smp_siblings
      to 2 as well.
      
      Boris: fixup ras/mce_amd_inj.c too, to compute the Node Base Core
      properly, according to the new nomenclature.
      
      Fixes: 1f12e32f ("x86/topology: Create logical package id")
      Reported-by: NXiong Zhou <jencce.kernel@gmail.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Cc: Andreas Herrmann <aherrmann@suse.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      Link: http://lkml.kernel.org/r/20160317095220.GO6344@twins.programming.kicks-ass.netSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      ee6825c8
  4. 26 3月, 2016 2 次提交
    • A
      mm, kasan: stackdepot implementation. Enable stackdepot for SLAB · cd11016e
      Alexander Potapenko 提交于
      Implement the stack depot and provide CONFIG_STACKDEPOT.  Stack depot
      will allow KASAN store allocation/deallocation stack traces for memory
      chunks.  The stack traces are stored in a hash table and referenced by
      handles which reside in the kasan_alloc_meta and kasan_free_meta
      structures in the allocated memory chunks.
      
      IRQ stack traces are cut below the IRQ entry point to avoid unnecessary
      duplication.
      
      Right now stackdepot support is only enabled in SLAB allocator.  Once
      KASAN features in SLAB are on par with those in SLUB we can switch SLUB
      to stackdepot as well, thus removing the dependency on SLUB stack
      bookkeeping, which wastes a lot of memory.
      
      This patch is based on the "mm: kasan: stack depots" patch originally
      prepared by Dmitry Chernenkov.
      
      Joonsoo has said that he plans to reuse the stackdepot code for the
      mm/page_owner.c debugging facility.
      
      [akpm@linux-foundation.org: s/depot_stack_handle/depot_stack_handle_t]
      [aryabinin@virtuozzo.com: comment style fixes]
      Signed-off-by: NAlexander Potapenko <glider@google.com>
      Signed-off-by: NAndrey Ryabinin <aryabinin@virtuozzo.com>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Pekka Enberg <penberg@kernel.org>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Andrey Konovalov <adech.fo@gmail.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Konstantin Serebryany <kcc@google.com>
      Cc: Dmitry Chernenkov <dmitryc@google.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      cd11016e
    • A
      arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections · be7635e7
      Alexander Potapenko 提交于
      KASAN needs to know whether the allocation happens in an IRQ handler.
      This lets us strip everything below the IRQ entry point to reduce the
      number of unique stack traces needed to be stored.
      
      Move the definition of __irq_entry to <linux/interrupt.h> so that the
      users don't need to pull in <linux/ftrace.h>.  Also introduce the
      __softirq_entry macro which is similar to __irq_entry, but puts the
      corresponding functions to the .softirqentry.text section.
      Signed-off-by: NAlexander Potapenko <glider@google.com>
      Acked-by: NSteven Rostedt <rostedt@goodmis.org>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Pekka Enberg <penberg@kernel.org>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Andrey Konovalov <adech.fo@gmail.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
      Cc: Konstantin Serebryany <kcc@google.com>
      Cc: Dmitry Chernenkov <dmitryc@google.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      be7635e7
  5. 23 3月, 2016 2 次提交
    • D
      kernel: add kcov code coverage · 5c9a8750
      Dmitry Vyukov 提交于
      kcov provides code coverage collection for coverage-guided fuzzing
      (randomized testing).  Coverage-guided fuzzing is a testing technique
      that uses coverage feedback to determine new interesting inputs to a
      system.  A notable user-space example is AFL
      (http://lcamtuf.coredump.cx/afl/).  However, this technique is not
      widely used for kernel testing due to missing compiler and kernel
      support.
      
      kcov does not aim to collect as much coverage as possible.  It aims to
      collect more or less stable coverage that is function of syscall inputs.
      To achieve this goal it does not collect coverage in soft/hard
      interrupts and instrumentation of some inherently non-deterministic or
      non-interesting parts of kernel is disbled (e.g.  scheduler, locking).
      
      Currently there is a single coverage collection mode (tracing), but the
      API anticipates additional collection modes.  Initially I also
      implemented a second mode which exposes coverage in a fixed-size hash
      table of counters (what Quentin used in his original patch).  I've
      dropped the second mode for simplicity.
      
      This patch adds the necessary support on kernel side.  The complimentary
      compiler support was added in gcc revision 231296.
      
      We've used this support to build syzkaller system call fuzzer, which has
      found 90 kernel bugs in just 2 months:
      
        https://github.com/google/syzkaller/wiki/Found-Bugs
      
      We've also found 30+ bugs in our internal systems with syzkaller.
      Another (yet unexplored) direction where kcov coverage would greatly
      help is more traditional "blob mutation".  For example, mounting a
      random blob as a filesystem, or receiving a random blob over wire.
      
      Why not gcov.  Typical fuzzing loop looks as follows: (1) reset
      coverage, (2) execute a bit of code, (3) collect coverage, repeat.  A
      typical coverage can be just a dozen of basic blocks (e.g.  an invalid
      input).  In such context gcov becomes prohibitively expensive as
      reset/collect coverage steps depend on total number of basic
      blocks/edges in program (in case of kernel it is about 2M).  Cost of
      kcov depends only on number of executed basic blocks/edges.  On top of
      that, kernel requires per-thread coverage because there are always
      background threads and unrelated processes that also produce coverage.
      With inlined gcov instrumentation per-thread coverage is not possible.
      
      kcov exposes kernel PCs and control flow to user-space which is
      insecure.  But debugfs should not be mapped as user accessible.
      
      Based on a patch by Quentin Casasnovas.
      
      [akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode']
      [akpm@linux-foundation.org: unbreak allmodconfig]
      [akpm@linux-foundation.org: follow x86 Makefile layout standards]
      Signed-off-by: NDmitry Vyukov <dvyukov@google.com>
      Reviewed-by: NKees Cook <keescook@chromium.org>
      Cc: syzkaller <syzkaller@googlegroups.com>
      Cc: Vegard Nossum <vegard.nossum@oracle.com>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Tavis Ormandy <taviso@google.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
      Cc: Kostya Serebryany <kcc@google.com>
      Cc: Eric Dumazet <edumazet@google.com>
      Cc: Alexander Potapenko <glider@google.com>
      Cc: Kees Cook <keescook@google.com>
      Cc: Bjorn Helgaas <bhelgaas@google.com>
      Cc: Sasha Levin <sasha.levin@oracle.com>
      Cc: David Drysdale <drysdale@google.com>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
      Cc: Kirill A. Shutemov <kirill@shutemov.name>
      Cc: Jiri Slaby <jslaby@suse.cz>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5c9a8750
    • A
      x86/compat: remove is_compat_task() · f970165b
      Andy Lutomirski 提交于
      x86's is_compat_task always checked the current syscall type, not the
      task type.  It has no non-arch users any more, so just remove it to
      avoid confusion.
      
      On x86, nothing should really be checking the task ABI.  There are
      legitimate users for the syscall ABI and for the mm ABI.
      Signed-off-by: NAndy Lutomirski <luto@kernel.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f970165b
  6. 22 3月, 2016 1 次提交
  7. 21 3月, 2016 4 次提交
    • H
      x86/cpufeature, perf/x86: Add AMD Accumulated Power Mechanism feature flag · 01fe03ff
      Huang Rui 提交于
      AMD CPU family 15h model 0x60 introduces a mechanism for measuring
      accumulated power. It is used to report the processor power consumption
      and support for it is indicated by CPUID Fn8000_0007_EDX[12].
      Signed-off-by: NHuang Rui <ray.huang@amd.com>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Cc: Aaron Lu <aaron.lu@intel.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Andreas Herrmann <herrmann.der.user@googlemail.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Fengguang Wu <fengguang.wu@intel.com>
      Cc: Frédéric Weisbecker <fweisbec@gmail.com>
      Cc: Guenter Roeck <linux@roeck-us.net>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Hector Marco-Gisbert <hecmargi@upv.es>
      Cc: Jacob Shin <jacob.w.shin@gmail.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: John Stultz <john.stultz@linaro.org>
      Cc: Kristen Carlson Accardi <kristen@linux.intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Robert Richter <rric@kernel.org>
      Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
      Cc: Stephane Eranian <eranian@google.com>
      Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vince Weaver <vincent.weaver@maine.edu>
      Cc: Wan Zongshun <Vincent.Wan@amd.com>
      Cc: spg_linux_kernel@amd.com
      Link: http://lkml.kernel.org/r/1452739808-11871-4-git-send-email-ray.huang@amd.com
      [ Resolved conflict and moved the synthetic CPUID slot to 19. ]
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      01fe03ff
    • H
      perf/x86/amd: Move nodes_per_socket into bsp_init_amd() · 8dfeae0d
      Huang Rui 提交于
      nodes_per_socket is static and it needn't be initialized many
      times during every CPU core init. So move its initialization into
      bsp_init_amd().
      Signed-off-by: NHuang Rui <ray.huang@amd.com>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Cc: Aaron Lu <aaron.lu@intel.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Andreas Herrmann <herrmann.der.user@googlemail.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Fengguang Wu <fengguang.wu@intel.com>
      Cc: Frédéric Weisbecker <fweisbec@gmail.com>
      Cc: Guenter Roeck <linux@roeck-us.net>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Hector Marco-Gisbert <hecmargi@upv.es>
      Cc: Jacob Shin <jacob.w.shin@gmail.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: John Stultz <john.stultz@linaro.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Robert Richter <rric@kernel.org>
      Cc: Stephane Eranian <eranian@google.com>
      Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vince Weaver <vincent.weaver@maine.edu>
      Cc: spg_linux_kernel@amd.com
      Link: http://lkml.kernel.org/r/1452739808-11871-2-git-send-email-ray.huang@amd.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      8dfeae0d
    • V
      perf/x86/mbm: Add Intel Memory B/W Monitoring enumeration and init · 33c3cc7a
      Vikas Shivappa 提交于
      The MBM init patch enumerates the Intel MBM (Memory b/w monitoring)
      and initializes the perf events and datastructures for monitoring the
      memory b/w.
      
      Its based on original patch series by Tony Luck and Kanaka Juvva.
      
      Memory bandwidth monitoring (MBM) provides OS/VMM a way to monitor
      bandwidth from one level of cache to another. The current patches
      support L3 external bandwidth monitoring. It supports both 'local
      bandwidth' and 'total bandwidth' monitoring for the socket. Local
      bandwidth measures the amount of data sent through the memory controller
      on the socket and total b/w measures the total system bandwidth.
      
      Extending the cache quality of service monitoring (CQM) we add two
      more events to the perf infrastructure:
      
        intel_cqm_llc/local_bytes - bytes sent through local socket memory controller
        intel_cqm_llc/total_bytes - total L3 external bytes sent
      
      The tasks are associated with a Resouce Monitoring ID (RMID) just like
      in CQM and OS uses a MSR write to indicate the RMID of the task during
      scheduling.
      Signed-off-by: NVikas Shivappa <vikas.shivappa@linux.intel.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Reviewed-by: NTony Luck <tony.luck@intel.com>
      Acked-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Matt Fleming <matt@codeblueprint.co.uk>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Stephane Eranian <eranian@google.com>
      Cc: Vince Weaver <vincent.weaver@maine.edu>
      Cc: fenghua.yu@intel.com
      Cc: h.peter.anvin@intel.com
      Cc: ravi.v.shankar@intel.com
      Cc: vikas.shivappa@intel.com
      Link: http://lkml.kernel.org/r/1457652732-4499-4-git-send-email-vikas.shivappa@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      33c3cc7a
    • A
      x86/kallsyms: fix GOLD link failure with new relative kallsyms table format · 142b9e6c
      Ard Biesheuvel 提交于
      Commit 2213e9a6 ("kallsyms: add support for relative offsets in
      kallsyms address table") changed the default kallsyms symbol table
      format to use relative references rather than absolute addresses.
      
      This reduces the size of the kallsyms symbol table by 50% on 64-bit
      architectures, and further reduces the size of the relocation tables
      used by relocatable kernels.  Since the memory footprint of the static
      kernel image is always much smaller than 4 GB, these relative references
      are assumed to be representable in 32 bits, even when the native word
      size is 64 bits.
      
      On 64-bit architectures, this obviously only works if the distance
      between each relative reference and the chosen anchor point is
      representable in 32 bits, and so the table generation code in
      scripts/kallsyms.c scans the table for the lowest value that is covered
      by the kernel text, and selects it as the anchor point.
      
      However, when using the GOLD linker rather than the default BFD linker
      to build the x86_64 kernel, the symbol phys_offset_64, which is the
      result of arithmetic defined in the linker script, is emitted as a 'T'
      rather than an 'A' type symbol, resulting in scripts/kallsyms.c to
      mistake it for a suitable anchor point, even though it is far away from
      the actual kernel image in the virtual address space.  This results in
      out-of-range warnings from scripts/kallsyms.c and a broken build.
      
      So let's align with the BFD linker, and emit the phys_offset_[32|64]
      symbols as absolute symbols explicitly.  Note that the out of range
      issue does not exist on 32-bit x86, but this patch changes both symbols
      for symmetry.
      Reported-by: NMarkus Trippelsdorf <markus@trippelsdorf.de>
      Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Guenter Roeck <linux@roeck-us.net>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      142b9e6c
  8. 19 3月, 2016 7 次提交