1. 26 7月, 2017 1 次提交
    • J
      x86/unwind: Add the ORC unwinder · ee9f8fce
      Josh Poimboeuf 提交于
      Add the new ORC unwinder which is enabled by CONFIG_ORC_UNWINDER=y.
      It plugs into the existing x86 unwinder framework.
      
      It relies on objtool to generate the needed .orc_unwind and
      .orc_unwind_ip sections.
      
      For more details on why ORC is used instead of DWARF, see
      Documentation/x86/orc-unwinder.txt - but the short version is
      that it's a simplified, fundamentally more robust debugninfo
      data structure, which also allows up to two orders of magnitude
      faster lookups than the DWARF unwinder - which matters to
      profiling workloads like perf.
      
      Thanks to Andy Lutomirski for the performance improvement ideas:
      splitting the ORC unwind table into two parallel arrays and creating a
      fast lookup table to search a subset of the unwind table.
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      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: Jiri Slaby <jslaby@suse.cz>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: live-patching@vger.kernel.org
      Link: http://lkml.kernel.org/r/0a6cbfb40f8da99b7a45a1a8302dc6aef16ec812.1500938583.git.jpoimboe@redhat.com
      [ Extended the changelog. ]
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      ee9f8fce
  2. 13 7月, 2017 2 次提交
    • D
      include/linux/string.h: add the option of fortified string.h functions · 6974f0c4
      Daniel Micay 提交于
      This adds support for compiling with a rough equivalent to the glibc
      _FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
      overflow checks for string.h functions when the compiler determines the
      size of the source or destination buffer at compile-time.  Unlike glibc,
      it covers buffer reads in addition to writes.
      
      GNU C __builtin_*_chk intrinsics are avoided because they would force a
      much more complex implementation.  They aren't designed to detect read
      overflows and offer no real benefit when using an implementation based
      on inline checks.  Inline checks don't add up to much code size and
      allow full use of the regular string intrinsics while avoiding the need
      for a bunch of _chk functions and per-arch assembly to avoid wrapper
      overhead.
      
      This detects various overflows at compile-time in various drivers and
      some non-x86 core kernel code.  There will likely be issues caught in
      regular use at runtime too.
      
      Future improvements left out of initial implementation for simplicity,
      as it's all quite optional and can be done incrementally:
      
      * Some of the fortified string functions (strncpy, strcat), don't yet
        place a limit on reads from the source based on __builtin_object_size of
        the source buffer.
      
      * Extending coverage to more string functions like strlcat.
      
      * It should be possible to optionally use __builtin_object_size(x, 1) for
        some functions (C strings) to detect intra-object overflows (like
        glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
        approach to avoid likely compatibility issues.
      
      * The compile-time checks should be made available via a separate config
        option which can be enabled by default (or always enabled) once enough
        time has passed to get the issues it catches fixed.
      
      Kees said:
       "This is great to have. While it was out-of-tree code, it would have
        blocked at least CVE-2016-3858 from being exploitable (improper size
        argument to strlcpy()). I've sent a number of fixes for
        out-of-bounds-reads that this detected upstream already"
      
      [arnd@arndb.de: x86: fix fortified memcpy]
        Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
      [keescook@chromium.org: avoid panic() in favor of BUG()]
        Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
      [keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
      Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
      Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.orgSigned-off-by: NDaniel Micay <danielmicay@gmail.com>
      Signed-off-by: NKees Cook <keescook@chromium.org>
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Acked-by: NKees Cook <keescook@chromium.org>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Daniel Axtens <dja@axtens.net>
      Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
      Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
      Cc: Chris Metcalf <cmetcalf@ezchip.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      6974f0c4
    • N
      kernel/watchdog: split up config options · 05a4a952
      Nicholas Piggin 提交于
      Split SOFTLOCKUP_DETECTOR from LOCKUP_DETECTOR, and split
      HARDLOCKUP_DETECTOR_PERF from HARDLOCKUP_DETECTOR.
      
      LOCKUP_DETECTOR implies the general boot, sysctl, and programming
      interfaces for the lockup detectors.
      
      An architecture that wants to use a hard lockup detector must define
      HAVE_HARDLOCKUP_DETECTOR_PERF or HAVE_HARDLOCKUP_DETECTOR_ARCH.
      
      Alternatively an arch can define HAVE_NMI_WATCHDOG, which provides the
      minimum arch_touch_nmi_watchdog, and it otherwise does its own thing and
      does not implement the LOCKUP_DETECTOR interfaces.
      
      sparc is unusual in that it has started to implement some of the
      interfaces, but not fully yet.  It should probably be converted to a full
      HAVE_HARDLOCKUP_DETECTOR_ARCH.
      
      [npiggin@gmail.com: fix]
        Link: http://lkml.kernel.org/r/20170617223522.66c0ad88@roar.ozlabs.ibm.com
      Link: http://lkml.kernel.org/r/20170616065715.18390-4-npiggin@gmail.comSigned-off-by: NNicholas Piggin <npiggin@gmail.com>
      Reviewed-by: NDon Zickus <dzickus@redhat.com>
      Reviewed-by: NBabu Moger <babu.moger@oracle.com>
      Tested-by: Babu Moger <babu.moger@oracle.com>	[sparc]
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      05a4a952
  3. 07 7月, 2017 2 次提交
    • A
      mm/hugetlb: clean up ARCH_HAS_GIGANTIC_PAGE · e1073d1e
      Aneesh Kumar K.V 提交于
      This moves the #ifdef in C code to a Kconfig dependency.  Also we move
      the gigantic_page_supported() function to be arch specific.
      
      This allows architectures to conditionally enable runtime allocation of
      gigantic huge page.  Architectures like ppc64 supports different
      gigantic huge page size (16G and 1G) based on the translation mode
      selected.  This provides an opportunity for ppc64 to enable runtime
      allocation only w.r.t 1G hugepage.
      
      No functional change in this patch.
      
      Link: http://lkml.kernel.org/r/1494995292-4443-1-git-send-email-aneesh.kumar@linux.vnet.ibm.comSigned-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
      Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e1073d1e
    • H
      mm, THP, swap: delay splitting THP during swap out · 38d8b4e6
      Huang Ying 提交于
      Patch series "THP swap: Delay splitting THP during swapping out", v11.
      
      This patchset is to optimize the performance of Transparent Huge Page
      (THP) swap.
      
      Recently, the performance of the storage devices improved so fast that
      we cannot saturate the disk bandwidth with single logical CPU when do
      page swap out even on a high-end server machine.  Because the
      performance of the storage device improved faster than that of single
      logical CPU.  And it seems that the trend will not change in the near
      future.  On the other hand, the THP becomes more and more popular
      because of increased memory size.  So it becomes necessary to optimize
      THP swap performance.
      
      The advantages of the THP swap support include:
      
       - Batch the swap operations for the THP to reduce lock
         acquiring/releasing, including allocating/freeing the swap space,
         adding/deleting to/from the swap cache, and writing/reading the swap
         space, etc. This will help improve the performance of the THP swap.
      
       - The THP swap space read/write will be 2M sequential IO. It is
         particularly helpful for the swap read, which are usually 4k random
         IO. This will improve the performance of the THP swap too.
      
       - It will help the memory fragmentation, especially when the THP is
         heavily used by the applications. The 2M continuous pages will be
         free up after THP swapping out.
      
       - It will improve the THP utilization on the system with the swap
         turned on. Because the speed for khugepaged to collapse the normal
         pages into the THP is quite slow. After the THP is split during the
         swapping out, it will take quite long time for the normal pages to
         collapse back into the THP after being swapped in. The high THP
         utilization helps the efficiency of the page based memory management
         too.
      
      There are some concerns regarding THP swap in, mainly because possible
      enlarged read/write IO size (for swap in/out) may put more overhead on
      the storage device.  To deal with that, the THP swap in should be turned
      on only when necessary.  For example, it can be selected via
      "always/never/madvise" logic, to be turned on globally, turned off
      globally, or turned on only for VMA with MADV_HUGEPAGE, etc.
      
      This patchset is the first step for the THP swap support.  The plan is
      to delay splitting THP step by step, finally avoid splitting THP during
      the THP swapping out and swap out/in the THP as a whole.
      
      As the first step, in this patchset, the splitting huge page is delayed
      from almost the first step of swapping out to after allocating the swap
      space for the THP and adding the THP into the swap cache.  This will
      reduce lock acquiring/releasing for the locks used for the swap cache
      management.
      
      With the patchset, the swap out throughput improves 15.5% (from about
      3.73GB/s to about 4.31GB/s) in the vm-scalability swap-w-seq test case
      with 8 processes.  The test is done on a Xeon E5 v3 system.  The swap
      device used is a RAM simulated PMEM (persistent memory) device.  To test
      the sequential swapping out, the test case creates 8 processes, which
      sequentially allocate and write to the anonymous pages until the RAM and
      part of the swap device is used up.
      
      This patch (of 5):
      
      In this patch, splitting huge page is delayed from almost the first step
      of swapping out to after allocating the swap space for the THP
      (Transparent Huge Page) and adding the THP into the swap cache.  This
      will batch the corresponding operation, thus improve THP swap out
      throughput.
      
      This is the first step for the THP swap optimization.  The plan is to
      delay splitting the THP step by step and avoid splitting the THP
      finally.
      
      In this patch, one swap cluster is used to hold the contents of each THP
      swapped out.  So, the size of the swap cluster is changed to that of the
      THP (Transparent Huge Page) on x86_64 architecture (512).  For other
      architectures which want such THP swap optimization,
      ARCH_USES_THP_SWAP_CLUSTER needs to be selected in the Kconfig file for
      the architecture.  In effect, this will enlarge swap cluster size by 2
      times on x86_64.  Which may make it harder to find a free cluster when
      the swap space becomes fragmented.  So that, this may reduce the
      continuous swap space allocation and sequential write in theory.  The
      performance test in 0day shows no regressions caused by this.
      
      In the future of THP swap optimization, some information of the swapped
      out THP (such as compound map count) will be recorded in the
      swap_cluster_info data structure.
      
      The mem cgroup swap accounting functions are enhanced to support charge
      or uncharge a swap cluster backing a THP as a whole.
      
      The swap cluster allocate/free functions are added to allocate/free a
      swap cluster for a THP.  A fair simple algorithm is used for swap
      cluster allocation, that is, only the first swap device in priority list
      will be tried to allocate the swap cluster.  The function will fail if
      the trying is not successful, and the caller will fallback to allocate a
      single swap slot instead.  This works good enough for normal cases.  If
      the difference of the number of the free swap clusters among multiple
      swap devices is significant, it is possible that some THPs are split
      earlier than necessary.  For example, this could be caused by big size
      difference among multiple swap devices.
      
      The swap cache functions is enhanced to support add/delete THP to/from
      the swap cache as a set of (HPAGE_PMD_NR) sub-pages.  This may be
      enhanced in the future with multi-order radix tree.  But because we will
      split the THP soon during swapping out, that optimization doesn't make
      much sense for this first step.
      
      The THP splitting functions are enhanced to support to split THP in swap
      cache during swapping out.  The page lock will be held during allocating
      the swap cluster, adding the THP into the swap cache and splitting the
      THP.  So in the code path other than swapping out, if the THP need to be
      split, the PageSwapCache(THP) will be always false.
      
      The swap cluster is only available for SSD, so the THP swap optimization
      in this patchset has no effect for HDD.
      
      [ying.huang@intel.com: fix two issues in THP optimize patch]
        Link: http://lkml.kernel.org/r/87k25ed8zo.fsf@yhuang-dev.intel.com
      [hannes@cmpxchg.org: extensive cleanups and simplifications, reduce code size]
      Link: http://lkml.kernel.org/r/20170515112522.32457-2-ying.huang@intel.comSigned-off-by: N"Huang, Ying" <ying.huang@intel.com>
      Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org>
      Suggested-by: Andrew Morton <akpm@linux-foundation.org> [for config option]
      Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> [for changes in huge_memory.c and huge_mm.h]
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Ebru Akagunduz <ebru.akagunduz@gmail.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Michal Hocko <mhocko@kernel.org>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Shaohua Li <shli@kernel.org>
      Cc: Minchan Kim <minchan@kernel.org>
      Cc: Rik van Riel <riel@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      38d8b4e6
  4. 02 7月, 2017 1 次提交
  5. 29 6月, 2017 1 次提交
  6. 23 6月, 2017 2 次提交
  7. 14 6月, 2017 1 次提交
  8. 13 6月, 2017 1 次提交
  9. 10 6月, 2017 1 次提交
    • D
      x86, uaccess: introduce copy_from_iter_flushcache for pmem / cache-bypass operations · 0aed55af
      Dan Williams 提交于
      The pmem driver has a need to transfer data with a persistent memory
      destination and be able to rely on the fact that the destination writes are not
      cached. It is sufficient for the writes to be flushed to a cpu-store-buffer
      (non-temporal / "movnt" in x86 terms), as we expect userspace to call fsync()
      to ensure data-writes have reached a power-fail-safe zone in the platform. The
      fsync() triggers a REQ_FUA or REQ_FLUSH to the pmem driver which will turn
      around and fence previous writes with an "sfence".
      
      Implement a __copy_from_user_inatomic_flushcache, memcpy_page_flushcache, and
      memcpy_flushcache, that guarantee that the destination buffer is not dirty in
      the cpu cache on completion. The new copy_from_iter_flushcache and sub-routines
      will be used to replace the "pmem api" (include/linux/pmem.h +
      arch/x86/include/asm/pmem.h). The availability of copy_from_iter_flushcache()
      and memcpy_flushcache() are gated by the CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE
      config symbol, and fallback to copy_from_iter_nocache() and plain memcpy()
      otherwise.
      
      This is meant to satisfy the concern from Linus that if a driver wants to do
      something beyond the normal nocache semantics it should be something private to
      that driver [1], and Al's concern that anything uaccess related belongs with
      the rest of the uaccess code [2].
      
      The first consumer of this interface is a new 'copy_from_iter' dax operation so
      that pmem can inject cache maintenance operations without imposing this
      overhead on other dax-capable drivers.
      
      [1]: https://lists.01.org/pipermail/linux-nvdimm/2017-January/008364.html
      [2]: https://lists.01.org/pipermail/linux-nvdimm/2017-April/009942.html
      
      Cc: <x86@kernel.org>
      Cc: Jan Kara <jack@suse.cz>
      Cc: Jeff Moyer <jmoyer@redhat.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Toshi Kani <toshi.kani@hpe.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Matthew Wilcox <mawilcox@microsoft.com>
      Reviewed-by: NRoss Zwisler <ross.zwisler@linux.intel.com>
      Signed-off-by: NDan Williams <dan.j.williams@intel.com>
      0aed55af
  10. 09 6月, 2017 1 次提交
  11. 05 6月, 2017 1 次提交
    • A
      x86/mm: Remove the UP asm/tlbflush.h code, always use the (formerly) SMP code · ce4a4e56
      Andy Lutomirski 提交于
      The UP asm/tlbflush.h generates somewhat nicer code than the SMP version.
      Aside from that, it's fallen quite a bit behind the SMP code:
      
       - flush_tlb_mm_range() didn't flush individual pages if the range
         was small.
      
       - The lazy TLB code was much weaker.  This usually wouldn't matter,
         but, if a kernel thread flushed its lazy "active_mm" more than
         once (due to reclaim or similar), it wouldn't be unlazied and
         would instead pointlessly flush repeatedly.
      
       - Tracepoints were missing.
      
      Aside from that, simply having the UP code around was a maintanence
      burden, since it means that any change to the TLB flush code had to
      make sure not to break it.
      
      Simplify everything by deleting the UP code.
      Signed-off-by: NAndy Lutomirski <luto@kernel.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Arjan van de Ven <arjan@linux.intel.com>
      Cc: Borislav Petkov <bpetkov@suse.de>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Nadav Amit <nadav.amit@gmail.com>
      Cc: Nadav Amit <namit@vmware.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-mm@kvack.org
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      ce4a4e56
  12. 24 5月, 2017 1 次提交
  13. 27 4月, 2017 2 次提交
  14. 23 4月, 2017 1 次提交
    • I
      Revert "x86/mm/gup: Switch GUP to the generic get_user_page_fast() implementation" · 6dd29b3d
      Ingo Molnar 提交于
      This reverts commit 2947ba05.
      
      Dan Williams reported dax-pmem kernel warnings with the following signature:
      
         WARNING: CPU: 8 PID: 245 at lib/percpu-refcount.c:155 percpu_ref_switch_to_atomic_rcu+0x1f5/0x200
         percpu ref (dax_pmem_percpu_release [dax_pmem]) <= 0 (0) after switching to atomic
      
      ... and bisected it to this commit, which suggests possible memory corruption
      caused by the x86 fast-GUP conversion.
      
      He also pointed out:
      
       "
        This is similar to the backtrace when we were not properly handling
        pud faults and was fixed with this commit: 220ced16 "mm: fix
        get_user_pages() vs device-dax pud mappings"
      
        I've found some missing _devmap checks in the generic
        get_user_pages_fast() path, but this does not fix the regression
        [...]
       "
      
      So given that there are known bugs, and a pretty robust looking bisection
      points to this commit suggesting that are unknown bugs in the conversion
      as well, revert it for the time being - we'll re-try in v4.13.
      Reported-by: NDan Williams <dan.j.williams@intel.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Michal Hocko <mhocko@suse.cz>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: aneesh.kumar@linux.vnet.ibm.com
      Cc: dann.frazier@canonical.com
      Cc: dave.hansen@intel.com
      Cc: steve.capper@linaro.org
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      6dd29b3d
  15. 18 4月, 2017 1 次提交
    • I
      x86: Enable KASLR by default · 6807c846
      Ingo Molnar 提交于
      KASLR is mature (and important) enough to be enabled by default on x86.
      
      Also enable it by default in the defconfigs.
      Acked-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Cc: dan.j.williams@intel.com
      Cc: dave.jiang@intel.com
      Cc: dyoung@redhat.com
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      6807c846
  16. 04 4月, 2017 1 次提交
  17. 30 3月, 2017 1 次提交
  18. 28 3月, 2017 1 次提交
  19. 24 3月, 2017 1 次提交
  20. 18 3月, 2017 1 次提交
  21. 13 3月, 2017 1 次提交
    • D
      x86/mm: Introduce mmap_compat_base() for 32-bit mmap() · 1b028f78
      Dmitry Safonov 提交于
      mmap() uses a base address, from which it starts to look for a free space
      for allocation.
      
      The base address is stored in mm->mmap_base, which is calculated during
      exec(). The address depends on task's size, set rlimit for stack, ASLR
      randomization. The base depends on the task size and the number of random
      bits which are different for 64-bit and 32bit applications.
      
      Due to the fact, that the base address is fixed, its mmap() from a compat
      (32bit) syscall issued by a 64bit task will return a address which is based
      on the 64bit base address and does not fit into the 32bit address space
      (4GB). The returned pointer is truncated to 32bit, which results in an
      invalid address.
      
      To solve store a seperate compat address base plus a compat legacy address
      base in mm_struct. These bases are calculated at exec() time and can be
      used later to address the 32bit compat mmap() issued by 64 bit
      applications.
      
      As a consequence of this change 32-bit applications issuing a 64-bit
      syscall (after doing a long jump) will get a 64-bit mapping now. Before
      this change 32-bit applications always got a 32bit mapping.
      
      [ tglx: Massaged changelog and added a comment ]
      Signed-off-by: NDmitry Safonov <dsafonov@virtuozzo.com>
      Cc: 0x7f454c46@gmail.com
      Cc: linux-mm@kvack.org
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Cyrill Gorcunov <gorcunov@openvz.org>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
      Link: http://lkml.kernel.org/r/20170306141721.9188-4-dsafonov@virtuozzo.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      1b028f78
  22. 08 3月, 2017 1 次提交
    • J
      stacktrace/x86: add function for detecting reliable stack traces · af085d90
      Josh Poimboeuf 提交于
      For live patching and possibly other use cases, a stack trace is only
      useful if it can be assured that it's completely reliable.  Add a new
      save_stack_trace_tsk_reliable() function to achieve that.
      
      Note that if the target task isn't the current task, and the target task
      is allowed to run, then it could be writing the stack while the unwinder
      is reading it, resulting in possible corruption.  So the caller of
      save_stack_trace_tsk_reliable() must ensure that the task is either
      'current' or inactive.
      
      save_stack_trace_tsk_reliable() relies on the x86 unwinder's detection
      of pt_regs on the stack.  If the pt_regs are not user-mode registers
      from a syscall, then they indicate an in-kernel interrupt or exception
      (e.g. preemption or a page fault), in which case the stack is considered
      unreliable due to the nature of frame pointers.
      
      It also relies on the x86 unwinder's detection of other issues, such as:
      
      - corrupted stack data
      - stack grows the wrong way
      - stack walk doesn't reach the bottom
      - user didn't provide a large enough entries array
      
      Such issues are reported by checking unwind_error() and !unwind_done().
      
      Also add CONFIG_HAVE_RELIABLE_STACKTRACE so arch-independent code can
      determine at build time whether the function is implemented.
      Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
      Reviewed-by: NMiroslav Benes <mbenes@suse.cz>
      Acked-by: Ingo Molnar <mingo@kernel.org>	# for the x86 changes
      Signed-off-by: NJiri Kosina <jkosina@suse.cz>
      af085d90
  23. 25 2月, 2017 1 次提交
  24. 22 2月, 2017 1 次提交
    • D
      arch: add ARCH_HAS_SET_MEMORY config · d2852a22
      Daniel Borkmann 提交于
      Currently, there's no good way to test for the presence of
      set_memory_ro/rw/x/nx() helpers implemented by archs such as
      x86, arm, arm64 and s390.
      
      There's DEBUG_SET_MODULE_RONX and DEBUG_RODATA, however both
      don't really reflect that: set_memory_*() are also available
      even when DEBUG_SET_MODULE_RONX is turned off, and DEBUG_RODATA
      is set by parisc, but doesn't implement above functions. Thus,
      add ARCH_HAS_SET_MEMORY that is selected by mentioned archs,
      where generic code can test against this.
      
      This also allows later on to move DEBUG_SET_MODULE_RONX out of
      the arch specific Kconfig to define it only once depending on
      ARCH_HAS_SET_MEMORY.
      Suggested-by: NLaura Abbott <labbott@redhat.com>
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      d2852a22
  25. 08 2月, 2017 1 次提交
  26. 07 2月, 2017 1 次提交
  27. 27 1月, 2017 1 次提交
  28. 24 1月, 2017 1 次提交
  29. 11 1月, 2017 1 次提交
  30. 17 12月, 2016 1 次提交
  31. 30 11月, 2016 2 次提交
    • I
      sched/x86: Make CONFIG_SCHED_MC_PRIO=y easier to enable · 0a21fc12
      Ingo Molnar 提交于
      Right now CONFIG_SCHED_MC_PRIO has X86_INTEL_PSTATE as a dependency,
      which is not enabled by default and which hides the CONFIG_SCHED_MC_PRIO
      hardware-enabling feature.
      
      Select X86_INTEL_PSTATE instead, plus its dependency (CPU_FREQ), if the
      user enables CONFIG_SCHED_MC_PRIO=y.
      
      (Also align the CONFIG_SCHED_MC_PRIO Kconfig help text in standard style.)
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tim Chen <tim.c.chen@linux.intel.com>
      Cc: bp@suse.de
      Cc: jolsa@redhat.com
      Cc: linux-acpi@vger.kernel.org
      Cc: linux-pm@vger.kernel.org
      Cc: rjw@rjwysocki.net
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      0a21fc12
    • T
      sched/x86: Change CONFIG_SCHED_ITMT to CONFIG_SCHED_MC_PRIO · de966cf4
      Tim Chen 提交于
      Rename CONFIG_SCHED_ITMT for Intel Turbo Boost Max Technology 3.0
      to CONFIG_SCHED_MC_PRIO.  This makes the configuration extensible
      in future to other architectures that wish to similarly establish
      CPU core priorities support in the scheduler.
      
      The description in Kconfig is updated to reflect this change with
      added details for better clarity.  The configuration is explicitly
      default-y, to enable the feature on CPUs that have this feature.
      
      It has no effect on non-TBM3 CPUs.
      Signed-off-by: NTim Chen <tim.c.chen@linux.intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: bp@suse.de
      Cc: jolsa@redhat.com
      Cc: linux-acpi@vger.kernel.org
      Cc: linux-pm@vger.kernel.org
      Cc: rjw@rjwysocki.net
      Link: http://lkml.kernel.org/r/2b2ee29d93e3f162922d72d0165a1405864fbb23.1480444902.git.tim.c.chen@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      de966cf4
  32. 25 11月, 2016 1 次提交
    • T
      x86: Enable Intel Turbo Boost Max Technology 3.0 · 5e76b2ab
      Tim Chen 提交于
      On platforms supporting Intel Turbo Boost Max Technology 3.0, the maximum
      turbo frequencies of some cores in a CPU package may be higher than for
      the other cores in the same package.  In that case, better performance
      (and possibly lower energy consumption as well) can be achieved by
      making the scheduler prefer to run tasks on the CPUs with higher max
      turbo frequencies.
      
      To that end, set up a core priority metric to abstract the core
      preferences based on the maximum turbo frequency.  In that metric,
      the cores with higher maximum turbo frequencies are higher-priority
      than the other cores in the same package and that causes the scheduler
      to favor them when making load-balancing decisions using the asymmertic
      packing approach.  At the same time, the priority of SMT threads with a
      higher CPU number is reduced so as to avoid scheduling tasks on all of
      the threads that belong to a favored core before all of the other cores
      have been given a task to run.
      
      The priority metric will be initialized by the P-state driver with the
      help of the sched_set_itmt_core_prio() function.  The P-state driver
      will also determine whether or not ITMT is supported by the platform
      and will call sched_set_itmt_support() to indicate that.
      Co-developed-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Co-developed-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
      Signed-off-by: NTim Chen <tim.c.chen@linux.intel.com>
      Cc: linux-pm@vger.kernel.org
      Cc: peterz@infradead.org
      Cc: jolsa@redhat.com
      Cc: rjw@rjwysocki.net
      Cc: linux-acpi@vger.kernel.org
      Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
      Cc: bp@suse.de
      Link: http://lkml.kernel.org/r/cd401ccdff88f88c8349314febdc25d51f7c48f7.1479844244.git.tim.c.chen@linux.intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      5e76b2ab
  33. 22 11月, 2016 1 次提交
    • Y
      x86/mce/AMD: Add system physical address translation for AMD Fam17h · f5382de9
      Yazen Ghannam 提交于
      The Unified Memory Controllers (UMCs) on Fam17h log a normalized address
      in their MCA_ADDR registers. We need to convert that normalized address
      to a system physical address in order to support a few facilities:
      
      1) To offline poisoned pages in DRAM proactively in the deferred error
         handler.
      
      2) To print sysaddr and page info for DRAM ECC errors in EDAC.
      
      [ Boris: fixes/cleanups ontop:
      
        * hi_addr_offset = 0 - no need for that branch. Stick it all under the
          HiAddrOffsetEn case. It confines hi_addr_offset's declaration too.
      
        * Move variables to the innermost scope they're used at so that we save
          on stack and not blow it up immediately on function entry.
      
        * Do not modify *sys_addr prematurely - we want to not exit early and
          have modified *sys_addr some, which callers get to see. We either
          convert to a sys_addr or we don't do anything. And we signal that with
          the retval of the function.
      
        * Rename label out -> out_err - because it is the error path.
      
        * No need to pr_err of the conversion failed case: imagine a
          sparsely-populated machine with UMCs which don't have DIMMs. Callers
          should look at the retval instead and issue a printk only when really
          necessary. No need for useless info in dmesg.
      
        * s/temp_reg/tmp/ and other variable names shortening => shorter code.
      
        * Use BIT() everywhere.
      
        * Make error messages more informative.
      
        *  Small build fix for the !CONFIG_X86_MCE_AMD case.
      
        * ... and more minor cleanups.
      ]
      Signed-off-by: NYazen Ghannam <Yazen.Ghannam@amd.com>
      Signed-off-by: NBorislav Petkov <bp@suse.de>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Aravind Gopalakrishnan <aravindksg.lkml@gmail.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: linux-edac <linux-edac@vger.kernel.org>
      Link: http://lkml.kernel.org/r/20161122111133.mjzpvzhf7o7yl2oa@pd.tnic
      [ Typo fixes. ]
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      f5382de9
  34. 16 11月, 2016 1 次提交
  35. 15 11月, 2016 1 次提交
    • I
      x86/kconfig: Sort the 'config X86' selects alphabetically · c763ea26
      Ingo Molnar 提交于
      This organizes the list a bit, plus reduces future conflicts (if people
      remember to insert new options alphabetically that is).
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      c763ea26