1. 18 5月, 2015 1 次提交
  2. 15 4月, 2015 2 次提交
  3. 13 4月, 2015 2 次提交
  4. 09 4月, 2015 1 次提交
    • A
      jump_label: Allow asm/jump_label.h to be included in assembly · 55dd0df7
      Anton Blanchard 提交于
      Wrap asm/jump_label.h for all archs with #ifndef __ASSEMBLY__.
      Since these are kernel only headers, we don't need #ifdef
      __KERNEL__ so can simplify things a bit.
      
      If an architecture wants to use jump labels in assembly, it
      will still need to define a macro to create the __jump_table
      entries (see ARCH_STATIC_BRANCH in the powerpc asm/jump_label.h
      for an example).
      Signed-off-by: NAnton Blanchard <anton@samba.org>
      Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: benh@kernel.crashing.org
      Cc: catalin.marinas@arm.com
      Cc: davem@davemloft.net
      Cc: heiko.carstens@de.ibm.com
      Cc: jbaron@akamai.com
      Cc: linux@arm.linux.org.uk
      Cc: linuxppc-dev@lists.ozlabs.org
      Cc: liuj97@gmail.com
      Cc: mgorman@suse.de
      Cc: mmarek@suse.cz
      Cc: mpe@ellerman.id.au
      Cc: paulus@samba.org
      Cc: ralf@linux-mips.org
      Cc: rostedt@goodmis.org
      Cc: schwidefsky@de.ibm.com
      Cc: will.deacon@arm.com
      Link: http://lkml.kernel.org/r/1428551492-21977-1-git-send-email-anton@samba.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
      55dd0df7
  5. 08 4月, 2015 1 次提交
  6. 24 3月, 2015 1 次提交
    • D
      sparc64: Fix several bugs in memmove(). · 2077cef4
      David S. Miller 提交于
      Firstly, handle zero length calls properly.  Believe it or not there
      are a few of these happening during early boot.
      
      Next, we can't just drop to a memcpy() call in the forward copy case
      where dst <= src.  The reason is that the cache initializing stores
      used in the Niagara memcpy() implementations can end up clearing out
      cache lines before we've sourced their original contents completely.
      
      For example, considering NG4memcpy, the main unrolled loop begins like
      this:
      
           load   src + 0x00
           load   src + 0x08
           load   src + 0x10
           load   src + 0x18
           load   src + 0x20
           store  dst + 0x00
      
      Assume dst is 64 byte aligned and let's say that dst is src - 8 for
      this memcpy() call.  That store at the end there is the one to the
      first line in the cache line, thus clearing the whole line, which thus
      clobbers "src + 0x28" before it even gets loaded.
      
      To avoid this, just fall through to a simple copy only mildly
      optimized for the case where src and dst are 8 byte aligned and the
      length is a multiple of 8 as well.  We could get fancy and call
      GENmemcpy() but this is good enough for how this thing is actually
      used.
      Reported-by: NDavid Ahern <david.ahern@oracle.com>
      Reported-by: NBob Picco <bpicco@meloft.net>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2077cef4
  7. 20 3月, 2015 4 次提交
  8. 19 3月, 2015 4 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
      sparc/PCI: Claim bus resources before pci_bus_add_devices() · a0c8a4d9
      Yijing Wang 提交于
      Pci_claim_bus_resources() should be called before pci_bus_add_devices(), or
      driver may failed to load, because the resources had not claimed.
      Signed-off-by: NYijing Wang <wangyijing@huawei.com>
      Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      a0c8a4d9
    • 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
    • D
      sparc: Fix /proc/kcore · 3c08158e
      David S. Miller 提交于
      /proc/kcore investigates the "System RAM" elements in /proc/iomem to
      initialize it's memory tables.  Therefore we have to register them
      before it tries to do so.  kcore uses device_initcall() so let's
      use arch_initcall() for the registry.
      
      Also we need ARCH_PROC_KCORE_TEXT to get the virtual addresses of
      the kernel image correct.
      Reported-by: NDavid Ahern <david.ahern@oracle.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3c08158e
  9. 13 3月, 2015 3 次提交
    • J
      clocksource, sparc32: Convert to using clocksource_register_hz() · 3142f760
      John Stultz 提交于
      While cleaning up some clocksource code, I noticed the
      time_32 implementation uses the clocksource_hz2mult()
      helper, but doesn't use the clocksource_register_hz()
      method.
      
      I don't believe the Sparc clocksource is a default
      clocksource, so we shouldn't need to self-define
      the mult/shift pair.
      
      So convert the time_32.c implementation to use
      clocksource_register_hz().
      
      Untested.
      Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
      Acked-by: NDavid S. Miller <davem@davemloft.net>
      Cc: Dave Jones <davej@codemonkey.org.uk>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Prarit Bhargava <prarit@redhat.com>
      Cc: Richard Cochran <richardcochran@gmail.com>
      Cc: Stephen Boyd <sboyd@codeaurora.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/1426133800-29329-11-git-send-email-john.stultz@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
      3142f760
    • J
      clocksource: Mostly kill clocksource_register() · f8935983
      John Stultz 提交于
      A long running project has been to clean up remaining uses
      of clocksource_register(), replacing it with the simpler
      clocksource_register_khz/hz() functions.
      
      However, there are a few cases where we need to self-define
      our mult/shift values, so switch the function to a more
      obviously internal __clocksource_register() name, and
      consolidate much of the internal logic so we don't have
      duplication.
      Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
      Cc: Dave Jones <davej@codemonkey.org.uk>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Prarit Bhargava <prarit@redhat.com>
      Cc: Richard Cochran <richardcochran@gmail.com>
      Cc: Stephen Boyd <sboyd@codeaurora.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/1426133800-29329-10-git-send-email-john.stultz@linaro.org
      [ Minor cleanups. ]
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      f8935983
    • Y
      PCI: Assign resources before drivers claim devices (pci_scan_bus()) · c90570d9
      Yijing Wang 提交于
      Previously, pci_scan_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_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_bus() and do it after any
      resource assignment in the callers.
      
      [bhelgaas: changelog, check for failure in mcf_pci_init()]
      Signed-off-by: NYijing Wang <wangyijing@huawei.com>
      Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      CC: "David S. Miller" <davem@davemloft.net>
      CC: Geert Uytterhoeven <geert@linux-m68k.org>
      CC: Guan Xuetao <gxt@mprc.pku.edu.cn>
      CC: Richard Henderson <rth@twiddle.net>
      CC: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      CC: Matt Turner <mattst88@gmail.com>
      c90570d9
  10. 04 3月, 2015 1 次提交
  11. 02 3月, 2015 4 次提交
  12. 14 2月, 2015 1 次提交
    • A
      mm: vmalloc: pass additional vm_flags to __vmalloc_node_range() · cb9e3c29
      Andrey Ryabinin 提交于
      For instrumenting global variables KASan will shadow memory backing memory
      for modules.  So on module loading we will need to allocate memory for
      shadow and map it at address in shadow that corresponds to the address
      allocated in module_alloc().
      
      __vmalloc_node_range() could be used for this purpose, except it puts a
      guard hole after allocated area.  Guard hole in shadow memory should be a
      problem because at some future point we might need to have a shadow memory
      at address occupied by guard hole.  So we could fail to allocate shadow
      for module_alloc().
      
      Now we have VM_NO_GUARD flag disabling guard page, so we need to pass into
      __vmalloc_node_range().  Add new parameter 'vm_flags' to
      __vmalloc_node_range() function.
      Signed-off-by: NAndrey Ryabinin <a.ryabinin@samsung.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: Konstantin Serebryany <kcc@google.com>
      Cc: Dmitry Chernenkov <dmitryc@google.com>
      Signed-off-by: NAndrey Konovalov <adech.fo@gmail.com>
      Cc: Yuri Gribov <tetra2005@gmail.com>
      Cc: Konstantin Khlebnikov <koct9i@gmail.com>
      Cc: Sasha Levin <sasha.levin@oracle.com>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Pekka Enberg <penberg@kernel.org>
      Cc: David Rientjes <rientjes@google.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      cb9e3c29
  13. 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
  14. 12 2月, 2015 4 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
    • K
      sparc32: fix broken set_pte() · 4ecf8860
      Kirill A. Shutemov 提交于
      32-bit sparc uses swap instruction to implement set_pte().  It called
      using GCC inline assembler.  But it misses the "memory" clobber to
      indicate that pte value will be updated in memory.
      
      As result GCC doesn't know that it cannot postpone pte pointer dereference
      which occurs before set_pte() to post-set_pte() time.
      
      It leads to real-world bugs -- [1]. In this situation we have code:
      
      	ptent = ptep_modify_prot_start(mm, addr, pte);
      	ptent = pte_modify(ptent, newprot);
      	...
      	ptep_modify_prot_commit(mm, addr, pte, ptent);
      
      ptep_modify_prot_start() in sparc case is just 'pte' dereference plus
      pte_clear().  pte_clear() calls broken set_pte().  GCC thinks it's valid
      to dereference 'pte' again on pte_modify() and gets cleared pte.
      ptep_modify_prot_commit() puts 'pteent' with pfn==0 back to page table,
      which eventually leads to the crash.
      
      [1] http://lkml.kernel.org/r/54C06B19.8060305@roeck-us.netSigned-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Reported-by: NGuenter Roeck <linux@roeck-us.net>
      Tested-by: NGuenter Roeck <linux@roeck-us.net>
      Cc: Paul Moore <pmoore@redhat.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: David Miller <davem@davemloft.net>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      4ecf8860
    • 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
  15. 11 2月, 2015 1 次提交
  16. 06 2月, 2015 1 次提交
  17. 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
  18. 20 1月, 2015 1 次提交
    • R
      module: remove mod arg from module_free, rename module_memfree(). · be1f221c
      Rusty Russell 提交于
      Nothing needs the module pointer any more, and the next patch will
      call it from RCU, where the module itself might no longer exist.
      Removing the arg is the safest approach.
      
      This just codifies the use of the module_alloc/module_free pattern
      which ftrace and bpf use.
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Cc: Mikael Starvik <starvik@axis.com>
      Cc: Jesper Nilsson <jesper.nilsson@axis.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Ley Foon Tan <lftan@altera.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Chris Metcalf <cmetcalf@ezchip.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: x86@kernel.org
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
      Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
      Cc: linux-cris-kernel@axis.com
      Cc: linux-kernel@vger.kernel.org
      Cc: linux-mips@linux-mips.org
      Cc: nios2-dev@lists.rocketboards.org
      Cc: linuxppc-dev@lists.ozlabs.org
      Cc: sparclinux@vger.kernel.org
      Cc: netdev@vger.kernel.org
      be1f221c
  19. 17 1月, 2015 1 次提交
  20. 13 1月, 2015 5 次提交