1. 19 5月, 2015 1 次提交
    • D
      mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler · 70ffdb93
      David Hildenbrand 提交于
      Introduce faulthandler_disabled() and use it to check for irq context and
      disabled pagefaults (via pagefault_disable()) in the pagefault handlers.
      
      Please note that we keep the in_atomic() checks in place - to detect
      whether in irq context (in which case preemption is always properly
      disabled).
      
      In contrast, preempt_disable() should never be used to disable pagefaults.
      With !CONFIG_PREEMPT_COUNT, preempt_disable() doesn't modify the preempt
      counter, and therefore the result of in_atomic() differs.
      We validate that condition by using might_fault() checks when calling
      might_sleep().
      
      Therefore, add a comment to faulthandler_disabled(), describing why this
      is needed.
      
      faulthandler_disabled() and pagefault_disable() are defined in
      linux/uaccess.h, so let's properly add that include to all relevant files.
      
      This patch is based on a patch from Thomas Gleixner.
      Reviewed-and-tested-by: NThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: David.Laight@ACULAB.COM
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: airlied@linux.ie
      Cc: akpm@linux-foundation.org
      Cc: benh@kernel.crashing.org
      Cc: bigeasy@linutronix.de
      Cc: borntraeger@de.ibm.com
      Cc: daniel.vetter@intel.com
      Cc: heiko.carstens@de.ibm.com
      Cc: herbert@gondor.apana.org.au
      Cc: hocko@suse.cz
      Cc: hughd@google.com
      Cc: mst@redhat.com
      Cc: paulus@samba.org
      Cc: ralf@linux-mips.org
      Cc: schwidefsky@de.ibm.com
      Cc: yang.shi@windriver.com
      Link: http://lkml.kernel.org/r/1431359540-32227-7-git-send-email-dahi@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      70ffdb93
  2. 15 4月, 2015 3 次提交
  3. 13 4月, 2015 1 次提交
  4. 12 4月, 2015 1 次提交
  5. 19 3月, 2015 2 次提交
    • B
      PCI: Cleanup control flow · 9e808eb6
      Bjorn Helgaas 提交于
      Return errors immediately so the straightline path is the normal,
      no-error path.  No functional change.
      Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      9e808eb6
    • Y
      PCI: Assign resources before drivers claim devices (pci_scan_root_bus()) · b97ea289
      Yijing Wang 提交于
      Previously, pci_scan_root_bus() created a root PCI bus, enumerated the
      devices on it, and called pci_bus_add_devices(), which made the devices
      available for drivers to claim them.
      
      Most callers assigned resources to devices after pci_scan_root_bus()
      returns, which may be after drivers have claimed the devices.  This is
      incorrect; the PCI core should not change device resources while a driver
      is managing the device.
      
      Remove pci_bus_add_devices() from pci_scan_root_bus() and do it after any
      resource assignment in the callers.
      
      Note that ARM's pci_common_init_dev() already called pci_bus_add_devices()
      after pci_scan_root_bus(), so we only need to remove the first call:
      
        pci_common_init_dev
          pcibios_init_hw
            pci_scan_root_bus
              pci_bus_add_devices        # first call
          pci_bus_assign_resources
          pci_bus_add_devices            # second call
      
      [bhelgaas: changelog, drop "root_bus" var in alpha common_init_pci(),
      return failure earlier in mn10300, add "return" in x86 pcibios_scan_root(),
      return early if xtensa platform_pcibios_fixup() fails]
      Signed-off-by: NYijing Wang <wangyijing@huawei.com>
      Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      CC: Richard Henderson <rth@twiddle.net>
      CC: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      CC: Matt Turner <mattst88@gmail.com>
      CC: David Howells <dhowells@redhat.com>
      CC: Tony Luck <tony.luck@intel.com>
      CC: Michal Simek <monstr@monstr.eu>
      CC: Ralf Baechle <ralf@linux-mips.org>
      CC: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
      CC: Sebastian Ott <sebott@linux.vnet.ibm.com>
      CC: "David S. Miller" <davem@davemloft.net>
      CC: Chris Metcalf <cmetcalf@ezchip.com>
      CC: Chris Zankel <chris@zankel.net>
      CC: Max Filippov <jcmvbkbc@gmail.com>
      CC: Thomas Gleixner <tglx@linutronix.de>
      b97ea289
  6. 10 3月, 2015 1 次提交
  7. 06 3月, 2015 1 次提交
  8. 13 2月, 2015 1 次提交
    • A
      all arches, signal: move restart_block to struct task_struct · f56141e3
      Andy Lutomirski 提交于
      If an attacker can cause a controlled kernel stack overflow, overwriting
      the restart block is a very juicy exploit target.  This is because the
      restart_block is held in the same memory allocation as the kernel stack.
      
      Moving the restart block to struct task_struct prevents this exploit by
      making the restart_block harder to locate.
      
      Note that there are other fields in thread_info that are also easy
      targets, at least on some architectures.
      
      It's also a decent simplification, since the restart code is more or less
      identical on all architectures.
      
      [james.hogan@imgtec.com: metag: align thread_info::supervisor_stack]
      Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: David Miller <davem@davemloft.net>
      Acked-by: NRichard Weinberger <richard@nod.at>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Cc: Matt Turner <mattst88@gmail.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Russell King <rmk@arm.linux.org.uk>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
      Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
      Cc: Steven Miao <realmz6@gmail.com>
      Cc: Mark Salter <msalter@redhat.com>
      Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
      Cc: Mikael Starvik <starvik@axis.com>
      Cc: Jesper Nilsson <jesper.nilsson@axis.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Richard Kuo <rkuo@codeaurora.org>
      Cc: "Luck, Tony" <tony.luck@intel.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Jonas Bonn <jonas@southpole.se>
      Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
      Cc: Helge Deller <deller@gmx.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
      Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Chen Liqin <liqin.linux@gmail.com>
      Cc: Lennox Wu <lennox.wu@gmail.com>
      Cc: Chris Metcalf <cmetcalf@ezchip.com>
      Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
      Cc: Chris Zankel <chris@zankel.net>
      Cc: Max Filippov <jcmvbkbc@gmail.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Guenter Roeck <linux@roeck-us.net>
      Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f56141e3
  9. 12 2月, 2015 3 次提交
    • A
      mm: gup: use get_user_pages_unlocked within get_user_pages_fast · a7b78075
      Andrea Arcangeli 提交于
      This allows the get_user_pages_fast slow path to release the mmap_sem
      before blocking.
      Signed-off-by: NAndrea Arcangeli <aarcange@redhat.com>
      Reviewed-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Andres Lagar-Cavilla <andreslc@google.com>
      Cc: Peter Feiner <pfeiner@google.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a7b78075
    • K
      mm: make FIRST_USER_ADDRESS unsigned long on all archs · d016bf7e
      Kirill A. Shutemov 提交于
      LKP has triggered a compiler warning after my recent patch "mm: account
      pmd page tables to the process":
      
          mm/mmap.c: In function 'exit_mmap':
       >> mm/mmap.c:2857:2: warning: right shift count >= width of type [enabled by default]
      
      The code:
      
       > 2857                WARN_ON(mm_nr_pmds(mm) >
         2858                                round_up(FIRST_USER_ADDRESS, PUD_SIZE) >> PUD_SHIFT);
      
      In this, on tile, we have FIRST_USER_ADDRESS defined as 0.  round_up() has
      the same type -- int.  PUD_SHIFT.
      
      I think the best way to fix it is to define FIRST_USER_ADDRESS as unsigned
      long.  On every arch for consistency.
      Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Reported-by: NWu Fengguang <fengguang.wu@intel.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d016bf7e
    • N
      mm/hugetlb: reduce arch dependent code around follow_huge_* · 61f77eda
      Naoya Horiguchi 提交于
      Currently we have many duplicates in definitions around
      follow_huge_addr(), follow_huge_pmd(), and follow_huge_pud(), so this
      patch tries to remove the m.  The basic idea is to put the default
      implementation for these functions in mm/hugetlb.c as weak symbols
      (regardless of CONFIG_ARCH_WANT_GENERAL_HUGETL B), and to implement
      arch-specific code only when the arch needs it.
      
      For follow_huge_addr(), only powerpc and ia64 have their own
      implementation, and in all other architectures this function just returns
      ERR_PTR(-EINVAL).  So this patch sets returning ERR_PTR(-EINVAL) as
      default.
      
      As for follow_huge_(pmd|pud)(), if (pmd|pud)_huge() is implemented to
      always return 0 in your architecture (like in ia64 or sparc,) it's never
      called (the callsite is optimized away) no matter how implemented it is.
      So in such architectures, we don't need arch-specific implementation.
      
      In some architecture (like mips, s390 and tile,) their current
      arch-specific follow_huge_(pmd|pud)() are effectively identical with the
      common code, so this patch lets these architecture use the common code.
      
      One exception is metag, where pmd_huge() could return non-zero but it
      expects follow_huge_pmd() to always return NULL.  This means that we need
      arch-specific implementation which returns NULL.  This behavior looks
      strange to me (because non-zero pmd_huge() implies that the architecture
      supports PMD-based hugepage, so follow_huge_pmd() can/should return some
      relevant value,) but that's beyond this cleanup patch, so let's keep it.
      
      Justification of non-trivial changes:
      - in s390, follow_huge_pmd() checks !MACHINE_HAS_HPAGE at first, and this
        patch removes the check. This is OK because we can assume MACHINE_HAS_HPAGE
        is true when follow_huge_pmd() can be called (note that pmd_huge() has
        the same check and always returns 0 for !MACHINE_HAS_HPAGE.)
      - in s390 and mips, we use HPAGE_MASK instead of PMD_MASK as done in common
        code. This patch forces these archs use PMD_MASK, but it's OK because
        they are identical in both archs.
        In s390, both of HPAGE_SHIFT and PMD_SHIFT are 20.
        In mips, HPAGE_SHIFT is defined as (PAGE_SHIFT + PAGE_SHIFT - 3) and
        PMD_SHIFT is define as (PAGE_SHIFT + PAGE_SHIFT + PTE_ORDER - 3), but
        PTE_ORDER is always 0, so these are identical.
      Signed-off-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Acked-by: NHugh Dickins <hughd@google.com>
      Cc: James Hogan <james.hogan@imgtec.com>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Mel Gorman <mel@csn.ul.ie>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Michal Hocko <mhocko@suse.cz>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Luiz Capitulino <lcapitulino@redhat.com>
      Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
      Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
      Cc: Steve Capper <steve.capper@linaro.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      61f77eda
  10. 11 2月, 2015 3 次提交
  11. 30 1月, 2015 1 次提交
    • L
      vm: add VM_FAULT_SIGSEGV handling support · 33692f27
      Linus Torvalds 提交于
      The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
      "you should SIGSEGV" error, because the SIGSEGV case was generally
      handled by the caller - usually the architecture fault handler.
      
      That results in lots of duplication - all the architecture fault
      handlers end up doing very similar "look up vma, check permissions, do
      retries etc" - but it generally works.  However, there are cases where
      the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.
      
      In particular, when accessing the stack guard page, libsigsegv expects a
      SIGSEGV.  And it usually got one, because the stack growth is handled by
      that duplicated architecture fault handler.
      
      However, when the generic VM layer started propagating the error return
      from the stack expansion in commit fee7e49d ("mm: propagate error
      from stack expansion even for guard page"), that now exposed the
      existing VM_FAULT_SIGBUS result to user space.  And user space really
      expected SIGSEGV, not SIGBUS.
      
      To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
      duplicate architecture fault handlers about it.  They all already have
      the code to handle SIGSEGV, so it's about just tying that new return
      value to the existing code, but it's all a bit annoying.
      
      This is the mindless minimal patch to do this.  A more extensive patch
      would be to try to gather up the mostly shared fault handling logic into
      one generic helper routine, and long-term we really should do that
      cleanup.
      
      Just from this patch, you can generally see that most architectures just
      copied (directly or indirectly) the old x86 way of doing things, but in
      the meantime that original x86 model has been improved to hold the VM
      semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
      "newer" things, so it would be a good idea to bring all those
      improvements to the generic case and teach other architectures about
      them too.
      Reported-and-tested-by: NTakashi Iwai <tiwai@suse.de>
      Tested-by: NJan Engelhardt <jengelh@inai.de>
      Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
      Cc: linux-arch@vger.kernel.org
      Cc: stable@vger.kernel.org
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      33692f27
  12. 19 1月, 2015 1 次提交
  13. 13 1月, 2015 3 次提交
    • M
      sh: macro whitespace fixes · 3237f28e
      Michael S. Tsirkin 提交于
      While working on arch/sh/include/asm/uaccess.h, I noticed
      that one macro within this header is made harder to read because it
      violates a coding style rule: space is missing after comma.
      
      Fix it up.
      Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      3237f28e
    • M
      sh: fix put_user sparse errors · 66959ed0
      Michael S. Tsirkin 提交于
      virtio wants to write bitwise types to userspace using put_user.
      At the moment this triggers sparse errors, since the value is passed
      through an integer.
      
      For example:
      
      	__le32 __user *p;
      	__le32 x;
      	put_user(x, p);
      
      is safe, but currently triggers a sparse warning.
      
      Fix that up using __force.
      
      Note: this does not suppress any useful sparse checks since caller
      assigns x to typeof(*p), which in turn forces all the necessary type
      checks.
      Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      66959ed0
    • M
      sh/uaccess: fix sparse errors · cad1c0df
      Michael S. Tsirkin 提交于
      virtio wants to read bitwise types from userspace using get_user.  At the
      moment this triggers sparse errors, since the value is passed through an
      integer.
      
      Fix that up using __force.
      Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      cad1c0df
  14. 20 12月, 2014 1 次提交
  15. 14 12月, 2014 1 次提交
  16. 11 12月, 2014 2 次提交
  17. 04 12月, 2014 1 次提交
  18. 15 11月, 2014 1 次提交
  19. 13 11月, 2014 1 次提交
    • D
      cpuidle: Invert CPUIDLE_FLAG_TIME_VALID logic · b82b6cca
      Daniel Lezcano 提交于
      The only place where the time is invalid is when the ACPI_CSTATE_FFH entry
      method is not set. Otherwise for all the drivers, the time can be correctly
      measured.
      
      Instead of duplicating the CPUIDLE_FLAG_TIME_VALID flag in all the drivers
      for all the states, just invert the logic by replacing it by the flag
      CPUIDLE_FLAG_TIME_INVALID, hence we can set this flag only for the acpi idle
      driver, remove the former flag from all the drivers and invert the logic with
      this flag in the different governor.
      Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
      Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
      b82b6cca
  20. 30 10月, 2014 1 次提交
  21. 10 10月, 2014 1 次提交
  22. 03 10月, 2014 1 次提交
  23. 25 9月, 2014 1 次提交
  24. 24 9月, 2014 2 次提交
    • E
      ARCH: AUDIT: audit_syscall_entry() should not require the arch · 91397401
      Eric Paris 提交于
      We have a function where the arch can be queried, syscall_get_arch().
      So rather than have every single piece of arch specific code use and/or
      duplicate syscall_get_arch(), just have the audit code use the
      syscall_get_arch() code.
      Based-on-patch-by: NRichard Briggs <rgb@redhat.com>
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Cc: linux-alpha@vger.kernel.org
      Cc: linux-arm-kernel@lists.infradead.org
      Cc: linux-ia64@vger.kernel.org
      Cc: microblaze-uclinux@itee.uq.edu.au
      Cc: linux-mips@linux-mips.org
      Cc: linux@lists.openrisc.net
      Cc: linux-parisc@vger.kernel.org
      Cc: linuxppc-dev@lists.ozlabs.org
      Cc: linux-s390@vger.kernel.org
      Cc: linux-sh@vger.kernel.org
      Cc: sparclinux@vger.kernel.org
      Cc: user-mode-linux-devel@lists.sourceforge.net
      Cc: linux-xtensa@linux-xtensa.org
      Cc: x86@kernel.org
      91397401
    • E
      SH: define syscall_get_arch() for superh · 37d181bb
      Eric Paris 提交于
      This patch defines syscall_get_arch() for the superh platform.  It does
      so in both syscall_32.h and syscall_64.h.  I'm not certain if the
      implementation in syscall_64.h couldn't just be used in syscall.h as I
      can't really track the setting of CONFIG_64BIT...
      
      This way is safe, but we might be able to combine these if a superh
      person were able to review...
      
      [v2]
      	fixed indentation stoopidity (Sergei Shtylyov)
      	use AUDIT_ARCH_SH instead of EM_SH
      Based-on-patch-by: NRichard Briggs <rgb@redhat.com>
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Cc: linux-sh@vger.kernel.org
      37d181bb
  25. 19 9月, 2014 1 次提交
  26. 14 9月, 2014 1 次提交
  27. 11 9月, 2014 1 次提交
  28. 10 9月, 2014 1 次提交
  29. 30 8月, 2014 1 次提交