1. 06 4月, 2019 1 次提交
    • V
      ARM: 8830/1: NOMMU: Toggle only bits in EXC_RETURN we are really care of · d8945878
      Vladimir Murzin 提交于
      [ Upstream commit 72cd4064fccaae15ab84d40d4be23667402df4ed ]
      
      ARMv8M introduces support for Security extension to M class, among
      other things it affects exception handling, especially, encoding of
      EXC_RETURN.
      
      The new bits have been added:
      
      Bit [6]	Secure or Non-secure stack
      Bit [5]	Default callee register stacking
      Bit [0]	Exception Secure
      
      which conflicts with hard-coded value of EXC_RETURN:
      
      In fact, we only care of few bits:
      
      Bit [3]	 Mode (0 - Handler, 1 - Thread)
      Bit [2]	 Stack pointer selection (0 - Main, 1 - Process)
      
      We can toggle only those bits and left other bits as they were on
      exception entry.
      
      It is basically, what patch does - saves EXC_RETURN when we do
      transition form Thread to Handler mode (it is first svc), so later
      saved value is used instead of EXC_RET_THREADMODE_PROCESSSTACK.
      Signed-off-by: NVladimir Murzin <vladimir.murzin@arm.com>
      Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
      Signed-off-by: NSasha Levin <sashal@kernel.org>
      d8945878
  2. 01 6月, 2018 1 次提交
  3. 27 11月, 2017 1 次提交
    • R
      ARM: avoid faulting on qemu · 3aaf33be
      Russell King 提交于
      When qemu starts a kernel in a bare environment, the default SCR has
      the AW and FW bits clear, which means that the kernel can't modify
      the PSR A or PSR F bits, and means that FIQs and imprecise aborts are
      always masked.
      
      When running uboot under qemu, the AW and FW SCR bits are set, and the
      kernel functions normally - and this is how real hardware behaves.
      
      Fix this for qemu by ignoring the FIQ bit.
      
      Fixes: 8bafae20 ("ARM: BUG if jumping to usermode address in kernel mode")
      Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
      3aaf33be
  4. 26 11月, 2017 1 次提交
  5. 02 11月, 2017 1 次提交
    • G
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman 提交于
      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: NKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: NPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  6. 07 7月, 2016 1 次提交
  7. 23 6月, 2016 1 次提交
  8. 27 8月, 2015 2 次提交
    • R
      ARM: entry: provide uaccess assembly macro hooks · 2190fed6
      Russell King 提交于
      Provide hooks into the kernel entry and exit paths to permit control
      of userspace visibility to the kernel.  The intended use is:
      
      - on entry to kernel from user, uaccess_disable will be called to
        disable userspace visibility
      - on exit from kernel to user, uaccess_enable will be called to
        enable userspace visibility
      - on entry from a kernel exception, uaccess_save_and_disable will be
        called to save the current userspace visibility setting, and disable
        access
      - on exit from a kernel exception, uaccess_restore will be called to
        restore the userspace visibility as it was before the exception
        occurred.
      
      These hooks allows us to keep userspace visibility disabled for the
      vast majority of the kernel, except for localised regions where we
      want to explicitly access userspace.
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      2190fed6
    • R
      ARM: entry: get rid of multiple macro definitions · aa06e5c1
      Russell King 提交于
      The following structure is just asking for trouble:
      
       #ifdef CONFIG_symbol
      	.macro foo
      	...
      	.endm
      	.macro bar
      	...
      	.endm
      	.macro baz
      	...
      	.endm
       #else
      	.macro foo
      	...
      	.endm
      	.macro bar
      	...
      	.endm
       #ifdef CONFIG_symbol2
      	.macro baz
      	...
      	.endm
       #else
      	.macro baz
      	...
      	.endm
       #endif
       #endif
      
      such as one defintion being updated, but the other definitions miss out.
      Where the contents of a macro needs to be conditional, the hint is in
      the first clause of this very sentence.  "contents" "conditional".  Not
      multiple separate definitions, especially not when much of the macro
      is the same between different configs.
      
      This patch fixes this bad style, which had caused the Thumb2 code to
      miss-out on the uaccess updates.
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      aa06e5c1
  9. 13 1月, 2015 1 次提交
  10. 26 9月, 2014 1 次提交
  11. 18 9月, 2014 1 次提交
    • D
      ARM: 8150/3: fiq: Replace default FIQ handler · c0e7f7ee
      Daniel Thompson 提交于
      This patch introduces a new default FIQ handler that is structured in a
      similar way to the existing ARM exception handler and result in the FIQ
      being handled by C code running on the SVC stack (despite this code run
      in the FIQ handler is subject to severe limitations with respect to
      locking making normal interaction with the kernel impossible).
      
      This default handler allows concepts that on x86 would be handled using
      NMIs to be realized on ARM.
      
      Credit:
      
          This patch is a near complete re-write of a patch originally
          provided by Anton Vorontsov. Today only a couple of small fragments
          survive, however without Anton's work to build from this patch would
          not exist. Thanks also to Russell King for spoonfeeding me a variety
          of fixes during the review cycle.
      Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Acked-by: NNicolas Pitre <nico@linaro.org>
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      c0e7f7ee
  12. 27 8月, 2014 1 次提交
    • M
      ARM: 8129/1: errata: work around Cortex-A15 erratum 830321 using dummy strex · 2c32c65e
      Mark Rutland 提交于
      On revisions of Cortex-A15 prior to r3p3, a CLREX instruction at PL1 may
      falsely trigger a watchpoint exception, leading to potential data aborts
      during exception return and/or livelock.
      
      This patch resolves the issue in the following ways:
      
        - Replacing our uses of CLREX with a dummy STREX sequence instead (as
          we did for v6 CPUs).
      
        - Removing the clrex code from v7_exit_coherency_flush and derivatives,
          since this only exists as a minor performance improvement when
          non-cached exclusives are in use (Linux doesn't use these).
      
      Benchmarking on a variety of ARM cores revealed no measurable
      performance difference with this change applied, so the change is
      performed unconditionally and no new Kconfig entry is added.
      Signed-off-by: NMark Rutland <mark.rutland@arm.com>
      Signed-off-by: NWill Deacon <will.deacon@arm.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      2c32c65e
  13. 18 7月, 2014 1 次提交
    • R
      ARM: convert all "mov.* pc, reg" to "bx reg" for ARMv6+ · 6ebbf2ce
      Russell King 提交于
      ARMv6 and greater introduced a new instruction ("bx") which can be used
      to return from function calls.  Recent CPUs perform better when the
      "bx lr" instruction is used rather than the "mov pc, lr" instruction,
      and this sequence is strongly recommended to be used by the ARM
      architecture manual (section A.4.1.1).
      
      We provide a new macro "ret" with all its variants for the condition
      code which will resolve to the appropriate instruction.
      
      Rather than doing this piecemeal, and miss some instances, change all
      the "mov pc" instances to use the new macro, with the exception of
      the "movs" instruction and the kprobes code.  This allows us to detect
      the "mov pc, lr" case and fix it up - and also gives us the possibility
      of deploying this for other registers depending on the CPU selection.
      Reported-by: NWill Deacon <will.deacon@arm.com>
      Tested-by: Stephen Warren <swarren@nvidia.com> # Tegra Jetson TK1
      Tested-by: Robert Jarzmik <robert.jarzmik@free.fr> # mioa701_bootresume.S
      Tested-by: Andrew Lunn <andrew@lunn.ch> # Kirkwood
      Tested-by: NShawn Guo <shawn.guo@freescale.com>
      Tested-by: Tony Lindgren <tony@atomide.com> # OMAPs
      Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com> # Armada XP, 375, 385
      Acked-by: Sekhar Nori <nsekhar@ti.com> # DaVinci
      Acked-by: Christoffer Dall <christoffer.dall@linaro.org> # kvm/hyp
      Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com> # PXA3xx
      Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> # Xen
      Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> # ARMv7M
      Tested-by: Simon Horman <horms+renesas@verge.net.au> # Shmobile
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      6ebbf2ce
  14. 02 6月, 2014 1 次提交
  15. 26 5月, 2014 1 次提交
  16. 09 4月, 2014 1 次提交
  17. 27 9月, 2013 1 次提交
  18. 18 4月, 2013 1 次提交
  19. 04 4月, 2013 1 次提交
    • K
      ARM: 7688/1: add support for context tracking subsystem · b0088480
      Kevin Hilman 提交于
      commit 91d1aa43 (context_tracking: New context tracking susbsystem)
      generalized parts of the RCU userspace extended quiescent state into
      the context tracking subsystem.  Context tracking is then used
      to implement adaptive tickless (a.k.a extended nohz)
      
      To support the new context tracking subsystem on ARM, the user/kernel
      boundary transtions need to be instrumented.
      
      For exceptions and IRQs in usermode, the existing usr_entry macro is
      used to instrument the user->kernel transition.  For the return to
      usermode path, the ret_to_user* path is instrumented.  Using the
      usr_entry macro, this covers interrupts in userspace, data abort and
      prefetch abort exceptions in userspace as well as undefined exceptions
      in userspace (which is where FP emulation and VFP are handled.)
      
      For syscalls, the slow return path is covered by instrumenting the
      ret_to_user path.  In addition, the syscall entry point is
      instrumented which covers the user->kernel transition for both fast
      and slow syscalls, and an additional instrumentation point is added
      for the fast syscall return path (ret_fast_syscall).
      
      Cc: Mats Liljegren <mats.liljegren@enea.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Signed-off-by: NKevin Hilman <khilman@linaro.org>
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      b0088480
  20. 03 4月, 2013 2 次提交
  21. 14 7月, 2011 1 次提交
  22. 02 7月, 2011 1 次提交
  23. 03 2月, 2011 1 次提交
  24. 06 12月, 2010 1 次提交
    • W
      ARM: hw_breakpoint: disable preemption during debug exception handling · 7e202696
      Will Deacon 提交于
      On ARM, debug exceptions occur in the form of data or prefetch aborts.
      One difference is that debug exceptions require access to per-cpu banked
      registers and data structures which are not saved in the low-level exception
      code. For kernels built with CONFIG_PREEMPT, there is an unlikely scenario
      that the debug handler ends up running on a different CPU from the one
      that originally signalled the event, resulting in random data being read
      from the wrong registers.
      
      This patch adds a debug_entry macro to the low-level exception handling
      code which checks whether the taken exception is a debug exception. If
      it is, the preempt count for the faulting process is incremented. After
      the debug handler has finished, the count is decremented.
      Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
      Signed-off-by: NWill Deacon <will.deacon@arm.com>
      7e202696
  25. 16 3月, 2010 1 次提交
  26. 14 10月, 2009 1 次提交
  27. 27 9月, 2009 1 次提交
  28. 19 9月, 2009 1 次提交
    • C
      Clear the exclusive monitor when returning from an exception · 200b812d
      Catalin Marinas 提交于
      The patch adds a CLREX or dummy STREX to the exception return path. This
      is needed because several atomic/locking operations use a pair of
      LDREX/STREXEQ and the EQ condition may not always be satisfied. This
      would leave the exclusive monitor status set and may cause problems with
      atomic/locking operations in the interrupted code.
      
      With this patch, the atomic_set() operation can be a simple STR
      instruction (on SMP systems, the global exclusive monitor is cleared by
      STR anyway). Clearing the exclusive monitor during context switch is no
      longer needed as this is handled by the exception return path anyway.
      Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
      Reported-by: NJamie Lokier <jamie@shareable.org>
      200b812d
  29. 24 7月, 2009 1 次提交
  30. 01 7月, 2006 1 次提交
  31. 24 3月, 2006 1 次提交
  32. 15 1月, 2006 1 次提交
  33. 10 9月, 2005 1 次提交
  34. 01 6月, 2005 1 次提交
    • R
      [PATCH] ARM SMP: convert alignment enable · 49f680ea
      Russell King 提交于
      The current vector entry system does not allow for SMP.  In
      order to work around this, we need to eliminate our reliance
      on the fixed save areas, which breaks the way we enable
      alignment traps.  This patch makes the alignment trap enable
      code independent of the way we handle the save areas.
      Signed-off-by: NRussell King <rmk@arm.linux.org.uk>
      49f680ea
  35. 26 4月, 2005 4 次提交