1. 21 Jan, 2016 10 commits
    • Stephen Boyd's avatar
      arch/frv/include/asm/io.h: accept const void pointers for read{b,w,l}() · ef5c16b8
      Stephen Boyd authored
      The SMD driver is reading and writing chunks of data to iomem, and
      there's an __iowrite32_copy() function for the writing part, but no
      __ioread32_copy() function for the reading part.  This series adds
      __ioread32_copy() and uses it in two places.
      
      This patch (of 4):
      
      The frv port uses compiler builtins, __builtin_read*(), for the I/O read
      routines.  Unfortunately, these don't accept const void pointers although
      the generic ASM implementations do, so generic code passing const pointers
      to these APIs cause compilers to emit warnings.  Add wrapper functions
      that cast away the const to avoid the warnings.
      Signed-off-by: default avatarStephen Boyd <sboyd@codeaurora.org>
      Cc: David Howells <dhowells@redhat.com>
      Cc: <zajec5@gmail.com>
      Cc: Bjorn Andersson <bjorn.andersson@sonymobile.com>
      Cc: Hauke Mehrtens <hauke@hauke-m.de>
      Cc: Paul Walmsley <paul@pwsan.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ef5c16b8
    • James Bottomley's avatar
      string_helpers: fix precision loss for some inputs · 564b026f
      James Bottomley authored
      It was noticed that we lose precision in the final calculation for some
      inputs.  The most egregious example is size=3000 blk_size=1900 in units
      of 10 should yield 5.70 MB but in fact yields 3.00 MB (oops).
      
      This is because the current algorithm doesn't correctly account for
      all the remainders in the logarithms.  Fix this by doing a correct
      calculation in the remainders based on napier's algorithm.
      
      Additionally, now we have the correct result, we have to account for
      arithmetic rounding because we're printing 3 digits of precision.  This
      means that if the fourth digit is five or greater, we have to round up,
      so add a section to ensure correct rounding.  Finally account for all
      possible inputs correctly, including zero for block size.
      
      Fixes: b9f28d86Signed-off-by: default avatarJames Bottomley <JBottomley@Odin.com>
      Reported-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
      Cc: <stable@vger.kernel.org>	[delay until after 4.4 release]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      564b026f
    • Martin Kepplinger's avatar
    • Joe Perches's avatar
      scripts/get_maintainer.pl: handle file names beginning with ./ · be17bddc
      Joe Perches authored
      The problem is that get_maintainer.pl doesn't work if you have a ./
      prefix on the filename.  For example, if you type:
      
        ./scripts/get_maintainer.pl -f ./drivers/usb/usb-skeleton.c
      
      then the current code only includes LKML and people from the git log, it
      doesn't include Greg or the linux-usb list.
      Reported-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
      Cc: Joe Perches <joe@perches.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      be17bddc
    • Randy Dunlap's avatar
      misc: ibmasm: fix build errors · 75339d82
      Randy Dunlap authored
      Fix build when CONFIG_SERIAL_8250=m and CONFIG_IBM_ASM=y.
      
      Fixes these build errors:
      
        drivers/built-in.o: In function `ibmasm_remove_one':
        module.c:(.text+0xf6874): undefined reference to `ibmasm_unregister_uart'
        drivers/built-in.o: In function `ibmasm_init_one':
        module.c:(.text+0xf6c37): undefined reference to `ibmasm_register_uart'
      Signed-off-by: default avatarRandy Dunlap <rdunlap@infradead.org>
      Cc: Max Asbock <masbock@us.ibm.com>
      Cc: Vernon Mauery <vernux@us.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      75339d82
    • Junil Lee's avatar
      zsmalloc: fix migrate_zspage-zs_free race condition · c102f07c
      Junil Lee authored
      record_obj() in migrate_zspage() does not preserve handle's
      HANDLE_PIN_BIT, set by find_aloced_obj()->trypin_tag(), and implicitly
      (accidentally) un-pins the handle, while migrate_zspage() still performs
      an explicit unpin_tag() on the that handle.  This additional explicit
      unpin_tag() introduces a race condition with zs_free(), which can pin
      that handle by this time, so the handle becomes un-pinned.
      
      Schematically, it goes like this:
      
        CPU0                                        CPU1
        migrate_zspage
          find_alloced_obj
            trypin_tag
              set HANDLE_PIN_BIT                    zs_free()
                                                      pin_tag()
        obj_malloc() -- new object, no tag
        record_obj() -- remove HANDLE_PIN_BIT           set HANDLE_PIN_BIT
        unpin_tag()  -- remove zs_free's HANDLE_PIN_BIT
      
      The race condition may result in a NULL pointer dereference:
      
        Unable to handle kernel NULL pointer dereference at virtual address 00000000
        CPU: 0 PID: 19001 Comm: CookieMonsterCl Tainted:
        PC is at get_zspage_mapping+0x0/0x24
        LR is at obj_free.isra.22+0x64/0x128
        Call trace:
           get_zspage_mapping+0x0/0x24
           zs_free+0x88/0x114
           zram_free_page+0x64/0xcc
           zram_slot_free_notify+0x90/0x108
           swap_entry_free+0x278/0x294
           free_swap_and_cache+0x38/0x11c
           unmap_single_vma+0x480/0x5c8
           unmap_vmas+0x44/0x60
           exit_mmap+0x50/0x110
           mmput+0x58/0xe0
           do_exit+0x320/0x8dc
           do_group_exit+0x44/0xa8
           get_signal+0x538/0x580
           do_signal+0x98/0x4b8
           do_notify_resume+0x14/0x5c
      
      This patch keeps the lock bit in migration path and update value
      atomically.
      Signed-off-by: default avatarJunil Lee <junil0814.lee@lge.com>
      Signed-off-by: default avatarMinchan Kim <minchan@kernel.org>
      Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
      Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
      Cc: <stable@vger.kernel.org> [4.1+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c102f07c
    • Guenter Roeck's avatar
      mm: arch: remove duplicate definitions of MADV_FREE · dcd6c87c
      Guenter Roeck authored
      Commits 21f55b01 ("arch/*/include/uapi/asm/mman.h: : let MADV_FREE
      have same value for all architectures") and ef58978f ("mm: define
      MADV_FREE for some arches") both defined MADV_FREE, but did not use the
      same values.  This results in build errors such as
      
        ./arch/alpha/include/uapi/asm/mman.h:53:0: error: "MADV_FREE" redefined
        ./arch/alpha/include/uapi/asm/mman.h:50:0: note: this is the location of the previous definition
      
      for the affected architectures.
      
      Fixes: 21f55b01 ("arch/*/include/uapi/asm/mman.h: : let MADV_FREE have same value for all architectures")
      Fixes: ef58978f ("mm: define MADV_FREE for some arches")
      Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
      Cc: Chen Gang <gang.chen.5i5j@gmail.com>
      Cc: Minchan Kim <minchan@kernel.org>
      Acked-by: Helge Deller <deller@gmx.de>	[parisc]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      dcd6c87c
    • Kirill A. Shutemov's avatar
      fs/proc/task_mmu.c: add workaround for old compilers · f4be6153
      Kirill A. Shutemov authored
      For THP=n, HPAGE_PMD_NR in smaps_account() expands to BUILD_BUG().
      That's fine since this codepath is eliminated by modern compilers.
      
      But older compilers have not that efficient dead code elimination.  It
      causes problem at least with gcc 4.1.2 on m68k:
      
         fs/built-in.o: In function `smaps_account':
         task_mmu.c:(.text+0x4f8fa): undefined reference to `__compiletime_assert_471'
      
      Let's replace HPAGE_PMD_NR with 1 << compound_order(page).
      Signed-off-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Reported-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      f4be6153
    • Kirill A. Shutemov's avatar
      thp: fix interrupt unsafe locking in split_huge_page() · 0b9b6fff
      Kirill A. Shutemov authored
      split_queue_lock can be taken from interrupt context in some cases, but
      I forgot to convert locking in split_huge_page() to interrupt-safe
      primitives.
      
      Let's fix this.
      
      lockdep output:
      
        ======================================================
        [ INFO: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected ]
        4.4.0+ #259 Tainted: G        W
        ------------------------------------------------------
        syz-executor/18183 [HC0[0]:SC0[2]:HE0:SE0] is trying to acquire:
         (split_queue_lock){+.+...}, at: free_transhuge_page+0x24/0x90 mm/huge_memory.c:3436
      
        and this task is already holding:
         (slock-AF_INET){+.-...}, at: spin_lock_bh include/linux/spinlock.h:307
         (slock-AF_INET){+.-...}, at: lock_sock_fast+0x45/0x120 net/core/sock.c:2462
        which would create a new lock dependency:
         (slock-AF_INET){+.-...} -> (split_queue_lock){+.+...}
      
        but this new dependency connects a SOFTIRQ-irq-safe lock:
         (slock-AF_INET){+.-...}
        ... which became SOFTIRQ-irq-safe at:
           mark_irqflags kernel/locking/lockdep.c:2799
           __lock_acquire+0xfd8/0x4700 kernel/locking/lockdep.c:3162
           lock_acquire+0x1dc/0x430 kernel/locking/lockdep.c:3585
           __raw_spin_lock include/linux/spinlock_api_smp.h:144
           _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151
           spin_lock include/linux/spinlock.h:302
           udp_queue_rcv_skb+0x781/0x1550 net/ipv4/udp.c:1680
           flush_stack+0x50/0x330 net/ipv6/udp.c:799
           __udp4_lib_mcast_deliver+0x694/0x7f0 net/ipv4/udp.c:1798
           __udp4_lib_rcv+0x17dc/0x23e0 net/ipv4/udp.c:1888
           udp_rcv+0x21/0x30 net/ipv4/udp.c:2108
           ip_local_deliver_finish+0x2b3/0xa50 net/ipv4/ip_input.c:216
           NF_HOOK_THRESH include/linux/netfilter.h:226
           NF_HOOK include/linux/netfilter.h:249
           ip_local_deliver+0x1c4/0x2f0 net/ipv4/ip_input.c:257
           dst_input include/net/dst.h:498
           ip_rcv_finish+0x5ec/0x1730 net/ipv4/ip_input.c:365
           NF_HOOK_THRESH include/linux/netfilter.h:226
           NF_HOOK include/linux/netfilter.h:249
           ip_rcv+0x963/0x1080 net/ipv4/ip_input.c:455
           __netif_receive_skb_core+0x1620/0x2f80 net/core/dev.c:4154
           __netif_receive_skb+0x2a/0x160 net/core/dev.c:4189
           netif_receive_skb_internal+0x1b5/0x390 net/core/dev.c:4217
           napi_skb_finish net/core/dev.c:4542
           napi_gro_receive+0x2bd/0x3c0 net/core/dev.c:4572
           e1000_clean_rx_irq+0x4e2/0x1100 drivers/net/ethernet/intel/e1000e/netdev.c:1038
           e1000_clean+0xa08/0x24a0 drivers/net/ethernet/intel/e1000/e1000_main.c:3819
           napi_poll net/core/dev.c:5074
           net_rx_action+0x7eb/0xdf0 net/core/dev.c:5139
           __do_softirq+0x26a/0x920 kernel/softirq.c:273
           invoke_softirq kernel/softirq.c:350
           irq_exit+0x18f/0x1d0 kernel/softirq.c:391
           exiting_irq ./arch/x86/include/asm/apic.h:659
           do_IRQ+0x86/0x1a0 arch/x86/kernel/irq.c:252
           ret_from_intr+0x0/0x20 arch/x86/entry/entry_64.S:520
           arch_safe_halt ./arch/x86/include/asm/paravirt.h:117
           default_idle+0x52/0x2e0 arch/x86/kernel/process.c:304
           arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:295
           default_idle_call+0x48/0xa0 kernel/sched/idle.c:92
           cpuidle_idle_call kernel/sched/idle.c:156
           cpu_idle_loop kernel/sched/idle.c:252
           cpu_startup_entry+0x554/0x710 kernel/sched/idle.c:300
           rest_init+0x192/0x1a0 init/main.c:412
           start_kernel+0x678/0x69e init/main.c:683
           x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:195
           x86_64_start_kernel+0x158/0x167 arch/x86/kernel/head64.c:184
      
        to a SOFTIRQ-irq-unsafe lock:
         (split_queue_lock){+.+...}
         which became SOFTIRQ-irq-unsafe at:
           mark_irqflags kernel/locking/lockdep.c:2817
           __lock_acquire+0x146e/0x4700 kernel/locking/lockdep.c:3162
           lock_acquire+0x1dc/0x430 kernel/locking/lockdep.c:3585
           __raw_spin_lock include/linux/spinlock_api_smp.h:144
           _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151
           spin_lock include/linux/spinlock.h:302
           split_huge_page_to_list+0xcc0/0x1c50 mm/huge_memory.c:3399
           split_huge_page include/linux/huge_mm.h:99
           queue_pages_pte_range+0xa38/0xef0 mm/mempolicy.c:507
           walk_pmd_range mm/pagewalk.c:50
           walk_pud_range mm/pagewalk.c:90
           walk_pgd_range mm/pagewalk.c:116
           __walk_page_range+0x653/0xcd0 mm/pagewalk.c:204
           walk_page_range+0xfe/0x2b0 mm/pagewalk.c:281
           queue_pages_range+0xfb/0x130 mm/mempolicy.c:687
           migrate_to_node mm/mempolicy.c:1004
           do_migrate_pages+0x370/0x4e0 mm/mempolicy.c:1109
           SYSC_migrate_pages mm/mempolicy.c:1453
           SyS_migrate_pages+0x640/0x730 mm/mempolicy.c:1374
           entry_SYSCALL_64_fastpath+0x16/0x7a arch/x86/entry/entry_64.S:185
      
        other info that might help us debug this:
      
         Possible interrupt unsafe locking scenario:
      
               CPU0                    CPU1
               ----                    ----
          lock(split_queue_lock);
                                       local_irq_disable();
                                       lock(slock-AF_INET);
                                       lock(split_queue_lock);
          <Interrupt>
            lock(slock-AF_INET);
      Signed-off-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Acked-by: default avatarDavid Rientjes <rientjes@google.com>
      Reviewed-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      0b9b6fff
    • Jean Delvare's avatar
      lib/libcrc32c.c: fix build warning · 290e0e0f
      Jean Delvare authored
      Fix the following build warning:
      
        lib/libcrc32c.c:42:5: warning: no previous prototype for "crc32c" [-Wmissing-prototypes]
         u32 crc32c(u32 crc, const void *address, unsigned int length)
             ^
      Signed-off-by: default avatarJean Delvare <jdelvare@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      290e0e0f
  2. 20 Jan, 2016 24 commits
  3. 19 Jan, 2016 6 commits