1. 03 Nov, 2017 3 commits
    • Chris Metcalf's avatar
      arch/tile: Implement ->set_state_oneshot_stopped() · 777a45b4
      Chris Metcalf authored
      set_state_oneshot_stopped() is called by the clkevt core, when the
      next event is required at an expiry time of 'KTIME_MAX'. This normally
      happens with NO_HZ_{IDLE|FULL} in both LOWRES/HIGHRES modes.
      
      This patch makes the clockevent device to stop on such an event, to
      avoid spurious interrupts, as explained by: commit 8fff52fd
      ("clockevents: Introduce CLOCK_EVT_STATE_ONESHOT_STOPPED state").
      Signed-off-by: default avatarChris Metcalf <cmetcalf@mellanox.com>
      777a45b4
    • Paul Burton's avatar
      Update MIPS email addresses · fb615d61
      Paul Burton authored
      MIPS will soon not be a part of Imagination Technologies, and as such
      many @imgtec.com email addresses will no longer be valid. This patch
      updates the addresses for those who:
      
       - Have 10 or more patches in mainline authored using an @imgtec.com
         email address, or any patches dated within the past year.
      
       - Are still with Imagination but leaving as part of the MIPS business
         unit, as determined from an internal email address list.
      
       - Haven't already updated their email address (ie. JamesH) or expressed
         a desire to be excluded (ie. Maciej).
      
       - Acked v2 or earlier of this patch, which leaves Deng-Cheng, Matt &
         myself.
      
      New addresses are of the form firstname.lastname@mips.com, and all
      verified against an internal email address list.  An entry is added to
      .mailmap for each person such that get_maintainer.pl will report the new
      addresses rather than @imgtec.com addresses which will soon be dead.
      
      Instances of the affected addresses throughout the tree are then
      mechanically replaced with the new @mips.com address.
      Signed-off-by: default avatarPaul Burton <paul.burton@mips.com>
      Cc: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
      Cc: Deng-Cheng Zhu <dengcheng.zhu@mips.com>
      Acked-by: default avatarDengcheng Zhu <dengcheng.zhu@mips.com>
      Cc: Matt Redfearn <matt.redfearn@imgtec.com>
      Cc: Matt Redfearn <matt.redfearn@mips.com>
      Acked-by: default avatarMatt Redfearn <matt.redfearn@mips.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: linux-kernel@vger.kernel.org
      Cc: linux-mips@linux-mips.org
      Cc: trivial@kernel.org
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      fb615d61
    • Rafael J. Wysocki's avatar
      x86: CPU: Fix up "cpu MHz" in /proc/cpuinfo · 941f5f0f
      Rafael J. Wysocki authored
      Commit 890da9cf (Revert "x86: do not use cpufreq_quick_get() for
      /proc/cpuinfo "cpu MHz"") is not sufficient to restore the previous
      behavior of "cpu MHz" in /proc/cpuinfo on x86 due to some changes
      made after the commit it has reverted.
      
      To address this, make the code in question use arch_freq_get_on_cpu()
      which also is used by cpufreq for reporting the current frequency of
      CPUs and since that function doesn't really depend on cpufreq in any
      way, drop the CONFIG_CPU_FREQ dependency for the object file
      containing it.
      
      Also refactor arch_freq_get_on_cpu() somewhat to avoid IPIs and
      return cached values right away if it is called very often over a
      short time (to prevent user space from triggering IPI storms through
      it).
      
      Fixes: 890da9cf (Revert "x86: do not use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz"")
      Cc: stable@kernel.org   # 4.13 - together with 890da9cfSigned-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      941f5f0f
  2. 02 Nov, 2017 6 commits
    • Madhavan Srinivasan's avatar
      powerpc/perf: Fix core-imc hotplug callback failure during imc initialization · 7ecb37f6
      Madhavan Srinivasan authored
      Call trace observed during boot:
      
        nest_capp0_imc performance monitor hardware support registered
        nest_capp1_imc performance monitor hardware support registered
        core_imc memory allocation for cpu 56 failed
        Unable to handle kernel paging request for data at address 0xffa400010
        Faulting instruction address: 0xc000000000bf3294
        0:mon> e
        cpu 0x0: Vector: 300 (Data Access) at [c000000ff38ff8d0]
            pc: c000000000bf3294: mutex_lock+0x34/0x90
            lr: c000000000bf3288: mutex_lock+0x28/0x90
            sp: c000000ff38ffb50
           msr: 9000000002009033
           dar: ffa400010
         dsisr: 80000
          current = 0xc000000ff383de00
          paca    = 0xc000000007ae0000	 softe: 0	 irq_happened: 0x01
            pid   = 13, comm = cpuhp/0
        Linux version 4.11.0-39.el7a.ppc64le (mockbuild@ppc-058.build.eng.bos.redhat.com) (gcc version 4.8.5 20150623 (Red Hat 4.8.5-16) (GCC) ) #1 SMP Tue Oct 3 07:42:44 EDT 2017
        0:mon> t
        [c000000ff38ffb80] c0000000002ddfac perf_pmu_migrate_context+0xac/0x470
        [c000000ff38ffc40] c00000000011385c ppc_core_imc_cpu_offline+0x1ac/0x1e0
        [c000000ff38ffc90] c000000000125758 cpuhp_invoke_callback+0x198/0x5d0
        [c000000ff38ffd00] c00000000012782c cpuhp_thread_fun+0x8c/0x3d0
        [c000000ff38ffd60] c0000000001678d0 smpboot_thread_fn+0x290/0x2a0
        [c000000ff38ffdc0] c00000000015ee78 kthread+0x168/0x1b0
        [c000000ff38ffe30] c00000000000b368 ret_from_kernel_thread+0x5c/0x74
      
      While registering the cpuhoplug callbacks for core-imc, if we fails
      in the cpuhotplug online path for any random core (either because opal call to
      initialize the core-imc counters fails or because memory allocation fails for
      that core), ppc_core_imc_cpu_offline() will get invoked for other cpus who
      successfully returned from cpuhotplug online path.
      
      But in the ppc_core_imc_cpu_offline() path we are trying to migrate the event
      context, when core-imc counters are not even initialized. Thus creating the
      above stack dump.
      
      Add a check to see if core-imc counters are enabled or not in the cpuhotplug
      offline path before migrating the context to handle this failing scenario.
      
      Fixes: 885dcd70 ("powerpc/perf: Add nest IMC PMU support")
      Signed-off-by: default avatarMadhavan Srinivasan <maddy@linux.vnet.ibm.com>
      Signed-off-by: default avatarAnju T Sudhakar <anju@linux.vnet.ibm.com>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      7ecb37f6
    • Linus Torvalds's avatar
      Revert "x86: do not use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz"" · 890da9cf
      Linus Torvalds authored
      This reverts commit 51204e06.
      
      There wasn't really any good reason for it, and people are complaining
      (rightly) that it broke existing practice.
      
      Cc: Len Brown <len.brown@intel.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      890da9cf
    • Mark Rutland's avatar
      arm64: ensure __dump_instr() checks addr_limit · 7a7003b1
      Mark Rutland authored
      It's possible for a user to deliberately trigger __dump_instr with a
      chosen kernel address.
      
      Let's avoid problems resulting from this by using get_user() rather than
      __get_user(), ensuring that we don't erroneously access kernel memory.
      
      Where we use __dump_instr() on kernel text, we already switch to
      KERNEL_DS, so this shouldn't adversely affect those cases.
      
      Fixes: 60ffc30d ("arm64: Exception handling")
      Cc: stable@vger.kernel.org
      Acked-by: default avatarWill Deacon <will.deacon@arm.com>
      Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      7a7003b1
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX license identifier to uapi header files with a license · e2be04c7
      Greg Kroah-Hartman authored
      Many user space API headers have licensing information, which is either
      incomplete, badly formatted or just a shorthand for referring to the
      license under which the file is supposed to be.  This makes it hard for
      compliance tools to determine the correct license.
      
      Update these files with an SPDX license identifier.  The identifier was
      chosen based on the license information in the file.
      
      GPL/LGPL licensed headers get the matching GPL/LGPL SPDX license
      identifier with the added 'WITH Linux-syscall-note' exception, which is
      the officially assigned exception identifier for the kernel syscall
      exception:
      
         NOTE! This copyright does *not* cover user programs that use kernel
         services by normal system calls - this is merely considered normal use
         of the kernel, and does *not* fall under the heading of "derived work".
      
      This exception makes it possible to include GPL headers into non GPL
      code, without confusing license compliance tools.
      
      Headers which have either explicit dual licensing or are just licensed
      under a non GPL license are updated with the corresponding SPDX
      identifier and the GPLv2 with syscall exception identifier.  The format
      is:
              ((GPL-2.0 WITH Linux-syscall-note) OR SPDX-ID-OF-OTHER-LICENSE)
      
      SPDX license identifiers are a legally binding shorthand, which can be
      used instead of the full boiler plate text.  The update does not remove
      existing license information as this has to be done on a case by case
      basis and the copyright holders might have to be consulted. This will
      happen in a separate step.
      
      This patch is based on work done by Thomas Gleixner and Kate Stewart and
      Philippe Ombredanne.  See the previous patch in this series for the
      methodology of how this patch was researched.
      Reviewed-by: default avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: default avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      e2be04c7
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX license identifier to uapi header files with no license · 6f52b16c
      Greg Kroah-Hartman authored
      Many user space API headers are missing licensing information, which
      makes it hard for compliance tools to determine the correct license.
      
      By default are files without license information under the default
      license of the kernel, which is GPLV2.  Marking them GPLV2 would exclude
      them from being included in non GPLV2 code, which is obviously not
      intended. The user space API headers fall under the syscall exception
      which is in the kernels COPYING file:
      
         NOTE! This copyright does *not* cover user programs that use kernel
         services by normal system calls - this is merely considered normal use
         of the kernel, and does *not* fall under the heading of "derived work".
      
      otherwise syscall usage would not be possible.
      
      Update the files which contain no license information with an SPDX
      license identifier.  The chosen identifier is 'GPL-2.0 WITH
      Linux-syscall-note' which is the officially assigned identifier for the
      Linux syscall exception.  SPDX license identifiers are a legally binding
      shorthand, which can be used instead of the full boiler plate text.
      
      This patch is based on work done by Thomas Gleixner and Kate Stewart and
      Philippe Ombredanne.  See the previous patch in this series for the
      methodology of how this patch was researched.
      Reviewed-by: default avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: default avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      6f52b16c
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman authored
      Many source files in the tree are missing licensing information, which
      makes it harder for compliance tools to determine the correct license.
      
      By default all files without license information are under the default
      license of the kernel, which is GPL version 2.
      
      Update the files which contain no license information with the 'GPL-2.0'
      SPDX license identifier.  The SPDX identifier is a legally binding
      shorthand, which can be used instead of the full boiler plate text.
      
      This patch is based on work done by Thomas Gleixner and Kate Stewart and
      Philippe Ombredanne.
      
      How this work was done:
      
      Patches were generated and checked against linux-4.14-rc6 for a subset of
      the use cases:
       - file had no licensing information it it.
       - file was a */uapi/* one with no licensing information in it,
       - file was a */uapi/* one with existing licensing information,
      
      Further patches will be generated in subsequent months to fix up cases
      where non-standard license headers were used, and references to license
      had to be inferred by heuristics based on keywords.
      
      The analysis to determine which SPDX License Identifier to be applied to
      a file was done in a spreadsheet of side by side results from of the
      output of two independent scanners (ScanCode & Windriver) producing SPDX
      tag:value files created by Philippe Ombredanne.  Philippe prepared the
      base worksheet, and did an initial spot review of a few 1000 files.
      
      The 4.13 kernel was the starting point of the analysis with 60,537 files
      assessed.  Kate Stewart did a file by file comparison of the scanner
      results in the spreadsheet to determine which SPDX license identifier(s)
      to be applied to the file. She confirmed any determination that was not
      immediately clear with lawyers working with the Linux Foundation.
      
      Criteria used to select files for SPDX license identifier tagging was:
       - Files considered eligible had to be source code files.
       - Make and config files were included as candidates if they contained >5
         lines of source
       - File already had some variant of a license header in it (even if <5
         lines).
      
      All documentation files were explicitly excluded.
      
      The following heuristics were used to determine which SPDX license
      identifiers to apply.
      
       - when both scanners couldn't find any license traces, file was
         considered to have no license information in it, and the top level
         COPYING file license applied.
      
         For non */uapi/* files that summary was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0                                              11139
      
         and resulted in the first patch in this series.
      
         If that file was a */uapi/* path one, it was "GPL-2.0 WITH
         Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0 WITH Linux-syscall-note                        930
      
         and resulted in the second patch in this series.
      
       - if a file had some form of licensing information in it, and was one
         of the */uapi/* ones, it was denoted with the Linux-syscall-note if
         any GPL family license was found in the file or had no licensing in
         it (per prior point).  Results summary:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|------
         GPL-2.0 WITH Linux-syscall-note                       270
         GPL-2.0+ WITH Linux-syscall-note                      169
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
         LGPL-2.1+ WITH Linux-syscall-note                      15
         GPL-1.0+ WITH Linux-syscall-note                       14
         ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
         LGPL-2.0+ WITH Linux-syscall-note                       4
         LGPL-2.1 WITH Linux-syscall-note                        3
         ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
         ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1
      
         and that resulted in the third patch in this series.
      
       - when the two scanners agreed on the detected license(s), that became
         the concluded license(s).
      
       - when there was disagreement between the two scanners (one detected a
         license but the other didn't, or they both detected different
         licenses) a manual inspection of the file occurred.
      
       - In most cases a manual inspection of the information in the file
         resulted in a clear resolution of the license that should apply (and
         which scanner probably needed to revisit its heuristics).
      
       - When it was not immediately clear, the license identifier was
         confirmed with lawyers working with the Linux Foundation.
      
       - If there was any question as to the appropriate license identifier,
         the file was flagged for further research and to be revisited later
         in time.
      
      In total, over 70 hours of logged manual review was done on the
      spreadsheet to determine the SPDX license identifiers to apply to the
      source files by Kate, Philippe, Thomas and, in some cases, confirmation
      by lawyers working with the Linux Foundation.
      
      Kate also obtained a third independent scan of the 4.13 code base from
      FOSSology, and compared selected files where the other two scanners
      disagreed against that SPDX file, to see if there was new insights.  The
      Windriver scanner is based on an older version of FOSSology in part, so
      they are related.
      
      Thomas did random spot checks in about 500 files from the spreadsheets
      for the uapi headers and agreed with SPDX license identifier in the
      files he inspected. For the non-uapi files Thomas did random spot checks
      in about 15000 files.
      
      In initial set of patches against 4.14-rc6, 3 files were found to have
      copy/paste license identifier errors, and have been fixed to reflect the
      correct identifier.
      
      Additionally Philippe spent 10 hours this week doing a detailed manual
      inspection and review of the 12,461 patched files from the initial patch
      version early this week with:
       - a full scancode scan run, collecting the matched texts, detected
         license ids and scores
       - reviewing anything where there was a license detected (about 500+
         files) to ensure that the applied SPDX license was correct
       - reviewing anything where there was no detection but the patch license
         was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
         SPDX license was correct
      
      This produced a worksheet with 20 files needing minor correction.  This
      worksheet was then exported into 3 different .csv files for the
      different types of files to be modified.
      
      These .csv files were then reviewed by Greg.  Thomas wrote a script to
      parse the csv files and add the proper SPDX tag to the file, in the
      format that the file expected.  This script was further refined by Greg
      based on the output to detect more types of files automatically and to
      distinguish between header and source .c files (which need different
      comment types.)  Finally Greg ran the script using the .csv files to
      generate the patches.
      Reviewed-by: default avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: default avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  3. 01 Nov, 2017 3 commits
    • Vlastimil Babka's avatar
      x86/mm: fix use-after-free of vma during userfaultfd fault · cb0631fd
      Vlastimil Babka authored
      Syzkaller with KASAN has reported a use-after-free of vma->vm_flags in
      __do_page_fault() with the following reproducer:
      
        mmap(&(0x7f0000000000/0xfff000)=nil, 0xfff000, 0x3, 0x32, 0xffffffffffffffff, 0x0)
        mmap(&(0x7f0000011000/0x3000)=nil, 0x3000, 0x1, 0x32, 0xffffffffffffffff, 0x0)
        r0 = userfaultfd(0x0)
        ioctl$UFFDIO_API(r0, 0xc018aa3f, &(0x7f0000002000-0x18)={0xaa, 0x0, 0x0})
        ioctl$UFFDIO_REGISTER(r0, 0xc020aa00, &(0x7f0000019000)={{&(0x7f0000012000/0x2000)=nil, 0x2000}, 0x1, 0x0})
        r1 = gettid()
        syz_open_dev$evdev(&(0x7f0000013000-0x12)="2f6465762f696e7075742f6576656e742300", 0x0, 0x0)
        tkill(r1, 0x7)
      
      The vma should be pinned by mmap_sem, but handle_userfault() might (in a
      return to userspace scenario) release it and then acquire again, so when
      we return to __do_page_fault() (with other result than VM_FAULT_RETRY),
      the vma might be gone.
      
      Specifically, per Andrea the scenario is
       "A return to userland to repeat the page fault later with a
        VM_FAULT_NOPAGE retval (potentially after handling any pending signal
        during the return to userland). The return to userland is identified
        whenever FAULT_FLAG_USER|FAULT_FLAG_KILLABLE are both set in
        vmf->flags"
      
      However, since commit a3c4fb7c ("x86/mm: Fix fault error path using
      unsafe vma pointer") there is a vma_pkey() read of vma->vm_flags after
      that point, which can thus become use-after-free.  Fix this by moving
      the read before calling handle_mm_fault().
      Reported-by: default avatarsyzbot <bot+6a5269ce759a7bb12754ed9622076dc93f65a1f6@syzkaller.appspotmail.com>
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Suggested-by: default avatarKirill A. Shutemov <kirill@shutemov.name>
      Fixes: 3c4fb7c9c2e ("x86/mm: Fix fault error path using unsafe vma pointer")
      Reviewed-by: default avatarAndrea Arcangeli <aarcange@redhat.com>
      Signed-off-by: default avatarVlastimil Babka <vbabka@suse.cz>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      cb0631fd
    • Naveen N. Rao's avatar
      powerpc/kprobes: Dereference function pointers only if the address does not belong to kernel text · e6c4dcb3
      Naveen N. Rao authored
      This makes the changes introduced in commit 83e840c7
      ("powerpc64/elfv1: Only dereference function descriptor for non-text
      symbols") to be specific to the kprobe subsystem.
      
      We previously changed ppc_function_entry() to always check the provided
      address to confirm if it needed to be dereferenced. This is actually
      only an issue for kprobe blacklisted asm labels (through use of
      _ASM_NOKPROBE_SYMBOL) and can cause other issues with ftrace. Also, the
      additional checks are not really necessary for our other uses.
      
      As such, move this check to the kprobes subsystem.
      
      Fixes: 83e840c7 ("powerpc64/elfv1: Only dereference function descriptor for non-text symbols")
      Cc: stable@vger.kernel.org # v4.13+
      Signed-off-by: default avatarNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      e6c4dcb3
    • Naveen N. Rao's avatar
      Revert "powerpc64/elfv1: Only dereference function descriptor for non-text symbols" · 63be1a81
      Naveen N. Rao authored
      This reverts commit 83e840c7 ("powerpc64/elfv1: Only dereference
      function descriptor for non-text symbols").
      
      Chandan reported that on newer kernels, trying to enable function_graph
      tracer on ppc64 (BE) locks up the system with the following trace:
      
        Unable to handle kernel paging request for data at address 0x600000002fa30010
        Faulting instruction address: 0xc0000000001f1300
        Thread overran stack, or stack corrupted
        Oops: Kernel access of bad area, sig: 11 [#1]
        BE SMP NR_CPUS=2048 DEBUG_PAGEALLOC NUMA pSeries
        Modules linked in:
        CPU: 1 PID: 6586 Comm: bash Not tainted 4.14.0-rc3-00162-g6e51f1f-dirty #20
        task: c000000625c07200 task.stack: c000000625c07310
        NIP:  c0000000001f1300 LR: c000000000121cac CTR: c000000000061af8
        REGS: c000000625c088c0 TRAP: 0380   Not tainted  (4.14.0-rc3-00162-g6e51f1f-dirty)
        MSR:  8000000000001032 <SF,ME,IR,DR,RI>  CR: 28002848  XER: 00000000
        CFAR: c0000000001f1320 SOFTE: 0
        ...
        NIP [c0000000001f1300] .__is_insn_slot_addr+0x30/0x90
        LR [c000000000121cac] .kernel_text_address+0x18c/0x1c0
        Call Trace:
        [c000000625c08b40] [c0000000001bd040] .is_module_text_address+0x20/0x40 (unreliable)
        [c000000625c08bc0] [c000000000121cac] .kernel_text_address+0x18c/0x1c0
        [c000000625c08c50] [c000000000061960] .prepare_ftrace_return+0x50/0x130
        [c000000625c08cf0] [c000000000061b10] .ftrace_graph_caller+0x14/0x34
        [c000000625c08d60] [c000000000121b40] .kernel_text_address+0x20/0x1c0
        [c000000625c08df0] [c000000000061960] .prepare_ftrace_return+0x50/0x130
        ...
        [c000000625c0ab30] [c000000000061960] .prepare_ftrace_return+0x50/0x130
        [c000000625c0abd0] [c000000000061b10] .ftrace_graph_caller+0x14/0x34
        [c000000625c0ac40] [c000000000121b40] .kernel_text_address+0x20/0x1c0
        [c000000625c0acd0] [c000000000061960] .prepare_ftrace_return+0x50/0x130
        [c000000625c0ad70] [c000000000061b10] .ftrace_graph_caller+0x14/0x34
        [c000000625c0ade0] [c000000000121b40] .kernel_text_address+0x20/0x1c0
      
      This is because ftrace is using ppc_function_entry() for obtaining the
      address of return_to_handler() in prepare_ftrace_return(). The call to
      kernel_text_address() itself gets traced and we end up in a recursive
      loop.
      
      Fixes: 83e840c7 ("powerpc64/elfv1: Only dereference function descriptor for non-text symbols")
      Cc: stable@vger.kernel.org # v4.13+
      Reported-by: default avatarChandan Rajendra <chandan@linux.vnet.ibm.com>
      Signed-off-by: default avatarNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      63be1a81
  4. 31 Oct, 2017 1 commit
    • Luc Van Oostenryck's avatar
      tile: pass machine size to sparse · ea82daf4
      Luc Van Oostenryck authored
      By default, sparse assumes a 64bit machine when compiled on x86-64
      and 32bit when compiled on anything else.
      
      This can of course create all sort of problems, like issuing false
      warnings like: 'constant ... is so big it is unsigned long long'
      or 'shift too big (32) for type unsigned long' when the architecture
      is 64bit while sparse was compiled on a 32bit machine, or worse,
      to not emit legitimate warnings in the reverse situation.
      
      Fix this by passing to sparse the appropriate -m32/-m64 flag.
      
      To: Chris Metcalf <cmetcalf@mellanox.com>
      Signed-off-by: default avatarLuc Van Oostenryck <luc.vanoostenryck@gmail.com>
      Signed-off-by: default avatarChris Metcalf <cmetcalf@mellanox.com>
      ea82daf4
  5. 27 Oct, 2017 1 commit
    • Ingo Molnar's avatar
      Revert "x86/mm: Limit mmap() of /dev/mem to valid physical addresses" · 90edaac6
      Ingo Molnar authored
      This reverts commit ce56a86e.
      
      There's unanticipated interaction with some boot parameters like 'mem=',
      which now cause the new checks via valid_mmap_phys_addr_range() to be too
      restrictive, crashing a Qemu bootup in fact, as reported by Fengguang Wu.
      
      So while the motivation of the change is still entirely valid, we
      need a few more rounds of testing to get it right - it's way too late
      after -rc6, so revert it for now.
      Reported-by: default avatarFengguang Wu <fengguang.wu@intel.com>
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      Acked-by: default avatarCraig Bergstrom <craigb@google.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Luis R. Rodriguez <mcgrof@suse.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Toshi Kani <toshi.kani@hp.com>
      Cc: dsafonov@virtuozzo.com
      Cc: kirill.shutemov@linux.intel.com
      Cc: mhocko@suse.com
      Cc: oleg@redhat.com
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      90edaac6
  6. 26 Oct, 2017 2 commits
    • Sebastian Andrzej Siewior's avatar
      arm/xen: don't inclide rwlock.h directly. · a494ee6c
      Sebastian Andrzej Siewior authored
      rwlock.h should not be included directly. Instead linux/splinlock.h
      should be included. One thing it does is to break the RT build.
      
      Cc: Stefano Stabellini <sstabellini@kernel.org>
      Cc: xen-devel@lists.xenproject.org
      Cc: linux-arm-kernel@lists.infradead.org
      Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
      Reviewed-by: default avatarStefano Stabellini <sstabellini@kernel.org>
      Signed-off-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
      a494ee6c
    • Lorenzo Pieralisi's avatar
      alpha/PCI: Move pci_map_irq()/pci_swizzle() out of initdata · 814eae59
      Lorenzo Pieralisi authored
      The introduction of {map/swizzle}_irq() hooks in the struct pci_host_bridge
      allowed to replace the pci_fixup_irqs() PCI IRQ allocation in alpha arch
      PCI code with per-bridge map/swizzle functions with commit 0e4c2eeb
      ("alpha/PCI: Replace pci_fixup_irqs() call with host bridge IRQ mapping
      hooks").
      
      As a side effect of converting PCI IRQ allocation to the struct
      pci_host_bridge {map/swizzle}_irq() hooks mechanism, the actual PCI IRQ
      allocation function (ie pci_assign_irq()) is carried out per-device in
      pci_device_probe() that is called when a PCI device driver is about to be
      probed.
      
      This means that, for drivers compiled as loadable modules, the actual PCI
      device IRQ allocation can now happen after the system has booted so the
      struct pci_host_bridge {map/swizzle}_irq() hooks pci_assign_irq() relies on
      must stay valid after the system has booted so that PCI core can carry out
      PCI IRQ allocation correctly.
      
      Most of the alpha board structures pci_map_irq() and pci_swizzle() hooks
      (that are used to initialize their struct pci_host_bridge equivalent
      through the alpha_mv global variable - that represents the struct
      alpha_machine_vector of the running kernel) are marked as
      __init/__initdata; this causes freed memory dereferences when PCI IRQ
      allocation is carried out after the kernel has booted (ie when loading PCI
      drivers as loadable module) because when the kernel tries to bind the PCI
      device to its (module) driver, the function pci_assign_irq() is called,
      that in turn retrieves the struct pci_host_bridge {map/swizzle}_irq() hooks
      to carry out PCI IRQ allocation; if those hooks are marked as __init
      code/__initdata they point at freed/invalid memory.
      
      Fix the issue by removing the __init/__initdata markers from all subarch
      struct alpha_machine_vector.pci_map_irq()/pci_swizzle() functions (and
      data).
      
      Fixes: 0e4c2eeb ("alpha/PCI: Replace pci_fixup_irqs() call with host bridge IRQ mapping hooks")
      Link: http://lkml.kernel.org/r/alpine.LRH.2.21.1710251043170.7098@math.ut.eeReported-by: default avatarMeelis Roos <mroos@linux.ee>
      Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
      Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Cc: Meelis Roos <mroos@linux.ee>
      Cc: Matt Turner <mattst88@gmail.com>
      814eae59
  7. 25 Oct, 2017 4 commits
  8. 24 Oct, 2017 1 commit
  9. 23 Oct, 2017 2 commits
  10. 22 Oct, 2017 1 commit
  11. 20 Oct, 2017 1 commit
    • Craig Bergstrom's avatar
      x86/mm: Limit mmap() of /dev/mem to valid physical addresses · ce56a86e
      Craig Bergstrom authored
      Currently, it is possible to mmap() any offset from /dev/mem.  If a
      program mmaps() /dev/mem offsets outside of the addressable limits
      of a system, the page table can be corrupted by setting reserved bits.
      
      For example if you mmap() offset 0x0001000000000000 of /dev/mem on an
      x86_64 system with a 48-bit bus, the page fault handler will be called
      with error_code set to RSVD.  The kernel then crashes with a page table
      corruption error.
      
      This change prevents this page table corruption on x86 by refusing
      to mmap offsets higher than the highest valid address in the system.
      Signed-off-by: default avatarCraig Bergstrom <craigb@google.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Luis R. Rodriguez <mcgrof@suse.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Toshi Kani <toshi.kani@hp.com>
      Cc: dsafonov@virtuozzo.com
      Cc: kirill.shutemov@linux.intel.com
      Cc: mhocko@suse.com
      Cc: oleg@redhat.com
      Link: http://lkml.kernel.org/r/20171019192856.39672-1-craigb@google.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      ce56a86e
  12. 19 Oct, 2017 5 commits
  13. 18 Oct, 2017 5 commits
  14. 17 Oct, 2017 2 commits
  15. 16 Oct, 2017 3 commits