1. 04 Jan, 2018 1 commit
  2. 05 Dec, 2017 2 commits
  3. 30 Nov, 2017 2 commits
  4. 02 Nov, 2017 4 commits
    • 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
  5. 21 Oct, 2017 2 commits
  6. 20 Oct, 2017 1 commit
  7. 17 Oct, 2017 2 commits
  8. 06 Oct, 2017 2 commits
  9. 04 Oct, 2017 1 commit
    • Mark Rutland's avatar
      arm64: Use larger stacks when KASAN is selected · b02faed1
      Mark Rutland authored
      AddressSanitizer instrumentation can significantly bloat the stack, and
      with GCC 7 this can result in stack overflows at boot time in some
      configurations.
      
      We can avoid this by doubling our stack size when KASAN is in use, as is
      already done on x86 (and has been since KASAN was introduced).
      Regardless of other patches to decrease KASAN's stack utilization,
      kernels built with KASAN will always require more stack space than those
      built without, and we should take this into account.
      Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      b02faed1
  10. 02 Oct, 2017 2 commits
  11. 29 Sep, 2017 2 commits
    • Will Deacon's avatar
      arm64: fault: Route pte translation faults via do_translation_fault · 760bfb47
      Will Deacon authored
      We currently route pte translation faults via do_page_fault, which elides
      the address check against TASK_SIZE before invoking the mm fault handling
      code. However, this can cause issues with the path walking code in
      conjunction with our word-at-a-time implementation because
      load_unaligned_zeropad can end up faulting in kernel space if it reads
      across a page boundary and runs into a page fault (e.g. by attempting to
      read from a guard region).
      
      In the case of such a fault, load_unaligned_zeropad has registered a
      fixup to shift the valid data and pad with zeroes, however the abort is
      reported as a level 3 translation fault and we dispatch it straight to
      do_page_fault, despite it being a kernel address. This results in calling
      a sleeping function from atomic context:
      
        BUG: sleeping function called from invalid context at arch/arm64/mm/fault.c:313
        in_atomic(): 0, irqs_disabled(): 0, pid: 10290
        Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
        [...]
        [<ffffff8e016cd0cc>] ___might_sleep+0x134/0x144
        [<ffffff8e016cd158>] __might_sleep+0x7c/0x8c
        [<ffffff8e016977f0>] do_page_fault+0x140/0x330
        [<ffffff8e01681328>] do_mem_abort+0x54/0xb0
        Exception stack(0xfffffffb20247a70 to 0xfffffffb20247ba0)
        [...]
        [<ffffff8e016844fc>] el1_da+0x18/0x78
        [<ffffff8e017f399c>] path_parentat+0x44/0x88
        [<ffffff8e017f4c9c>] filename_parentat+0x5c/0xd8
        [<ffffff8e017f5044>] filename_create+0x4c/0x128
        [<ffffff8e017f59e4>] SyS_mkdirat+0x50/0xc8
        [<ffffff8e01684e30>] el0_svc_naked+0x24/0x28
        Code: 36380080 d5384100 f9400800 9402566d (d4210000)
        ---[ end trace 2d01889f2bca9b9f ]---
      
      Fix this by dispatching all translation faults to do_translation_faults,
      which avoids invoking the page fault logic for faults on kernel addresses.
      
      Cc: <stable@vger.kernel.org>
      Reported-by: default avatarAnkit Jain <ankijain@codeaurora.org>
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      760bfb47
    • Will Deacon's avatar
      arm64: mm: Use READ_ONCE when dereferencing pointer to pte table · f069faba
      Will Deacon authored
      On kernels built with support for transparent huge pages, different CPUs
      can access the PMD concurrently due to e.g. fast GUP or page_vma_mapped_walk
      and they must take care to use READ_ONCE to avoid value tearing or caching
      of stale values by the compiler. Unfortunately, these functions call into
      our pgtable macros, which don't use READ_ONCE, and compiler caching has
      been observed to cause the following crash during ext4 writeback:
      
      PC is at check_pte+0x20/0x170
      LR is at page_vma_mapped_walk+0x2e0/0x540
      [...]
      Process doio (pid: 2463, stack limit = 0xffff00000f2e8000)
      Call trace:
      [<ffff000008233328>] check_pte+0x20/0x170
      [<ffff000008233758>] page_vma_mapped_walk+0x2e0/0x540
      [<ffff000008234adc>] page_mkclean_one+0xac/0x278
      [<ffff000008234d98>] rmap_walk_file+0xf0/0x238
      [<ffff000008236e74>] rmap_walk+0x64/0xa0
      [<ffff0000082370c8>] page_mkclean+0x90/0xa8
      [<ffff0000081f3c64>] clear_page_dirty_for_io+0x84/0x2a8
      [<ffff00000832f984>] mpage_submit_page+0x34/0x98
      [<ffff00000832fb4c>] mpage_process_page_bufs+0x164/0x170
      [<ffff00000832fc8c>] mpage_prepare_extent_to_map+0x134/0x2b8
      [<ffff00000833530c>] ext4_writepages+0x484/0xe30
      [<ffff0000081f6ab4>] do_writepages+0x44/0xe8
      [<ffff0000081e5bd4>] __filemap_fdatawrite_range+0xbc/0x110
      [<ffff0000081e5e68>] file_write_and_wait_range+0x48/0xd8
      [<ffff000008324310>] ext4_sync_file+0x80/0x4b8
      [<ffff0000082bd434>] vfs_fsync_range+0x64/0xc0
      [<ffff0000082332b4>] SyS_msync+0x194/0x1e8
      
      This is because page_vma_mapped_walk loads the PMD twice before calling
      pte_offset_map: the first time without READ_ONCE (where it gets all zeroes
      due to a concurrent pmdp_invalidate) and the second time with READ_ONCE
      (where it sees a valid table pointer due to a concurrent pmd_populate).
      However, the compiler inlines everything and caches the first value in
      a register, which is subsequently used in pte_offset_phys which returns
      a junk pointer that is later dereferenced when attempting to access the
      relevant pte.
      
      This patch fixes the issue by using READ_ONCE in pte_offset_phys to ensure
      that a stale value is not used. Whilst this is a point fix for a known
      failure (and simple to backport), a full fix moving all of our page table
      accessors over to {READ,WRITE}_ONCE and consistently using READ_ONCE in
      page_vma_mapped_walk is in the works for a future kernel release.
      
      Cc: Jon Masters <jcm@redhat.com>
      Cc: Timur Tabi <timur@codeaurora.org>
      Cc: <stable@vger.kernel.org>
      Fixes: f27176cf ("mm: convert page_mkclean_one() to use page_vma_mapped_walk()")
      Tested-by: default avatarRichard Ruigrok <rruigrok@codeaurora.org>
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      f069faba
  12. 27 Sep, 2017 1 commit
  13. 26 Sep, 2017 1 commit
  14. 21 Sep, 2017 1 commit
  15. 19 Sep, 2017 2 commits
  16. 18 Sep, 2017 3 commits
  17. 17 Sep, 2017 2 commits
  18. 16 Sep, 2017 1 commit
    • Heiko Stuebner's avatar
      Revert "arm64: dts: rockchip: Add basic cpu frequencies for RK3368" · 6354a06c
      Heiko Stuebner authored
      This reverts commit 6f2dea1f.
      
      Without accurate cpu regulators being set for boards this will wreak havoc
      when cpufreq-dt begins to set new frequencies without adjusting the core
      frequency.
      
      Additionally the rk3368 has an unsolved issue in that it has two separate
      cpu clusters with separate clock lines but only one cpu supply regulator
      for both clusters, which causes even more problems.
      
      While it seems that originally only one cluster was supposed to be active
      at a time (big or little), talking with real users of the hardware
      revealed that having all 8 cores accessible at 1.2GHz max is way more
      liked than having 4 cores at 1.5GHz max. Such an approach needs changes
      to cpufreq and/or opp though to control the two separate clock lines when
      setting both clusters to the same frequencies.
      
      In any case, having the OPPs in the dts at this point in time is
      undesireable, so remove them again for now.
      Signed-off-by: default avatarHeiko Stuebner <heiko@sntech.de>
      6354a06c
  19. 14 Sep, 2017 1 commit
  20. 09 Sep, 2017 1 commit
  21. 05 Sep, 2017 6 commits