1. 22 Sep, 2015 31 commits
    • David Vrabel's avatar
      x86/xen: make CONFIG_XEN depend on CONFIG_X86_LOCAL_APIC · e4987cc7
      David Vrabel authored
      commit 87ffd2b9 upstream.
      
      Since commit feb44f1f (x86/xen:
      Provide a "Xen PV" APIC driver to support >255 VCPUs) Xen guests need
      a full APIC driver and thus should depend on X86_LOCAL_APIC.
      
      This fixes an i386 build failure with !SMP && !CONFIG_X86_UP_APIC by
      disabling Xen support in this configuration.
      
      Users needing Xen support in a non-SMP i386 kernel will need to enable
      CONFIG_X86_UP_APIC.
      Signed-off-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      e4987cc7
    • Takashi Iwai's avatar
      ALSA: usb-audio: Fix runtime PM unbalance · 240fcd54
      Takashi Iwai authored
      commit 9003ebb1 upstream.
      
      The fix for deadlock in PM in commit [1ee23fe0: ALSA: usb-audio:
      Fix deadlocks at resuming] introduced a new check of in_pm flag.
      However, the brainless patch author evaluated it in a wrong way
      (logical AND instead of logical OR), thus usb_autopm_get_interface()
      is wrongly called at probing, leading to unbalance of runtime PM
      refcount.
      
      This patch fixes it by correcting the logic.
      Reported-by: default avatarHans Yang <hansy@nvidia.com>
      Fixes: 1ee23fe0 ('ALSA: usb-audio: Fix deadlocks at resuming')
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      240fcd54
    • Alan Stern's avatar
      SCSI: Fix NULL pointer dereference in runtime PM · 35e0b63d
      Alan Stern authored
      commit 49718f0f upstream.
      
      The routines in scsi_rpm.c assume that if a runtime-PM callback is
      invoked for a SCSI device, it can only mean that the device's driver
      has asked the block layer to handle the runtime power management (by
      calling blk_pm_runtime_init(), which among other things sets q->dev).
      
      However, this assumption turns out to be wrong for things like the ses
      driver.  Normally ses devices are not allowed to do runtime PM, but
      userspace can override this setting.  If this happens, the kernel gets
      a NULL pointer dereference when blk_post_runtime_resume() tries to use
      the uninitialized q->dev pointer.
      
      This patch fixes the problem by calling the block layer's runtime-PM
      routines only if the device's driver really does have a runtime-PM
      callback routine.  Since ses doesn't define any such callbacks, the
      crash won't occur.
      
      This fixes Bugzilla #101371.
      Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
      Reported-by: default avatarStanisław Pitucha <viraptor@gmail.com>
      Reported-by: default avatarIlan Cohen <ilanco@gmail.com>
      Tested-by: default avatarIlan Cohen <ilanco@gmail.com>
      Reviewed-by: default avatarJohannes Thumshirn <jthumshirn@suse.de>
      Signed-off-by: default avatarJames Bottomley <JBottomley@Odin.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      35e0b63d
    • Hiral Shah's avatar
      fnic: Use the local variable instead of I/O flag to acquire io_req_lock in... · 55f53a66
      Hiral Shah authored
      fnic: Use the local variable instead of I/O flag to acquire io_req_lock in fnic_queuecommand() to avoid deadloack
      
      commit db196935 upstream.
      
      We added changes in fnic driver patch 1.6.0.16 to acquire
      io_req_lock in fnic_queuecommand() before issuing I/O so that io completion
      is serialized. But when releasing the lock we check for the I/O flag and
      this could be modified if IO abort occurs before I/O completion. In this case
      we wont release the lock and causes deadlock in some scenerios. Using the
      local variable to check the IO lock status will resolve the problem.
      
      Fixes: 41df7b02Signed-off-by: default avatarHiral Shah <hishah@cisco.com>
      Signed-off-by: default avatarSesidhar Baddela <sebaddel@cisco.com>
      Signed-off-by: default avatarAnil Chintalapati <achintal@cisco.com>
      Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
      Signed-off-by: default avatarJames Bottomley <JBottomley@Odin.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      55f53a66
    • Chris Wilson's avatar
      drm/i915: Flag the execlists context object as dirty after every use · 4f77fc8b
      Chris Wilson authored
      commit 903ecd0b upstream.
      
      Everytime we use the logical context with execlists it becomes dirty (as
      the hardware will write the new register values afterwards, as well as
      the GPU state that will be used). We need to then flag the context as
      dirty everytime since after a swap-out/swap-in cycle the dirty flag will
      be cleared, and a further swap-out cycle will then loose the most recent
      GPU state.
      Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
      Reviewed-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
      Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      4f77fc8b
    • Andy Lutomirski's avatar
      x86/ldt: Further fix FPU emulation · 6165ee47
      Andy Lutomirski authored
      commit 12e244f4 upstream.
      
      The previous fix confused a selector with a segment prefix.  Fix it.
      
      Compile-tested only.
      
      Cc: Juergen Gross <jgross@suse.com>
      Reported-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Fixes: 4809146b ("x86/ldt: Correct FPU emulation access to LDT")
      Signed-off-by: default avatarAndy Lutomirski <luto@kernel.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      6165ee47
    • Markos Chandras's avatar
      MIPS: Fix seccomp syscall argument for MIPS64 · c323bae0
      Markos Chandras authored
      commit 9f161439 upstream.
      
      Commit 4c21b8fd ("MIPS: seccomp: Handle indirect system calls (o32)")
      fixed indirect system calls on O32 but it also introduced a bug for MIPS64
      where it erroneously modified the v0 (syscall) register with the assumption
      that the sycall offset hasn't been taken into consideration. This breaks
      seccomp on MIPS64 n64 and n32 ABIs. We fix this by replacing the addition
      with a move instruction.
      
      Fixes: 4c21b8fd ("MIPS: seccomp: Handle indirect system calls (o32)")
      Reviewed-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Signed-off-by: default avatarMarkos Chandras <markos.chandras@imgtec.com>
      Cc: linux-mips@linux-mips.org
      Patchwork: https://patchwork.linux-mips.org/patch/10951/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      c323bae0
    • Manfred Spraul's avatar
      ipc/sem.c: update/correct memory barriers · 54cd766f
      Manfred Spraul authored
      commit 3ed1f8a9 upstream.
      
      sem_lock() did not properly pair memory barriers:
      
      !spin_is_locked() and spin_unlock_wait() are both only control barriers.
      The code needs an acquire barrier, otherwise the cpu might perform read
      operations before the lock test.
      
      As no primitive exists inside <include/spinlock.h> and since it seems
      noone wants another primitive, the code creates a local primitive within
      ipc/sem.c.
      
      With regards to -stable:
      
      The change of sem_wait_array() is a bugfix, the change to sem_lock() is a
      nop (just a preprocessor redefinition to improve the readability).  The
      bugfix is necessary for all kernels that use sem_wait_array() (i.e.:
      starting from 3.10).
      Signed-off-by: default avatarManfred Spraul <manfred@colorfullife.com>
      Reported-by: default avatarOleg Nesterov <oleg@redhat.com>
      Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
      Cc: Kirill Tkhai <ktkhai@parallels.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Davidlohr Bueso <dave@stgolabs.net>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      54cd766f
    • Herton R. Krzesinski's avatar
      ipc,sem: fix use after free on IPC_RMID after a task using same semaphore set exits · 89055eb6
      Herton R. Krzesinski authored
      commit 602b8593 upstream.
      
      The current semaphore code allows a potential use after free: in
      exit_sem we may free the task's sem_undo_list while there is still
      another task looping through the same semaphore set and cleaning the
      sem_undo list at freeary function (the task called IPC_RMID for the same
      semaphore set).
      
      For example, with a test program [1] running which keeps forking a lot
      of processes (which then do a semop call with SEM_UNDO flag), and with
      the parent right after removing the semaphore set with IPC_RMID, and a
      kernel built with CONFIG_SLAB, CONFIG_SLAB_DEBUG and
      CONFIG_DEBUG_SPINLOCK, you can easily see something like the following
      in the kernel log:
      
         Slab corruption (Not tainted): kmalloc-64 start=ffff88003b45c1c0, len=64
         000: 6b 6b 6b 6b 6b 6b 6b 6b 00 6b 6b 6b 6b 6b 6b 6b  kkkkkkkk.kkkkkkk
         010: ff ff ff ff 6b 6b 6b 6b ff ff ff ff ff ff ff ff  ....kkkk........
         Prev obj: start=ffff88003b45c180, len=64
         000: 00 00 00 00 ad 4e ad de ff ff ff ff 5a 5a 5a 5a  .....N......ZZZZ
         010: ff ff ff ff ff ff ff ff c0 fb 01 37 00 88 ff ff  ...........7....
         Next obj: start=ffff88003b45c200, len=64
         000: 00 00 00 00 ad 4e ad de ff ff ff ff 5a 5a 5a 5a  .....N......ZZZZ
         010: ff ff ff ff ff ff ff ff 68 29 a7 3c 00 88 ff ff  ........h).<....
         BUG: spinlock wrong CPU on CPU#2, test/18028
         general protection fault: 0000 [#1] SMP
         Modules linked in: 8021q mrp garp stp llc nf_conntrack_ipv4 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables binfmt_misc ppdev input_leds joydev parport_pc parport floppy serio_raw virtio_balloon virtio_rng virtio_console virtio_net iosf_mbi crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcspkr qxl ttm drm_kms_helper drm snd_hda_codec_generic i2c_piix4 snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd soundcore crc32c_intel virtio_pci virtio_ring virtio pata_acpi ata_generic [last unloaded: speedstep_lib]
         CPU: 2 PID: 18028 Comm: test Not tainted 4.2.0-rc5+ #1
         Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014
         RIP: spin_dump+0x53/0xc0
         Call Trace:
           spin_bug+0x30/0x40
           do_raw_spin_unlock+0x71/0xa0
           _raw_spin_unlock+0xe/0x10
           freeary+0x82/0x2a0
           ? _raw_spin_lock+0xe/0x10
           semctl_down.clone.0+0xce/0x160
           ? __do_page_fault+0x19a/0x430
           ? __audit_syscall_entry+0xa8/0x100
           SyS_semctl+0x236/0x2c0
           ? syscall_trace_leave+0xde/0x130
           entry_SYSCALL_64_fastpath+0x12/0x71
         Code: 8b 80 88 03 00 00 48 8d 88 60 05 00 00 48 c7 c7 a0 2c a4 81 31 c0 65 8b 15 eb 40 f3 7e e8 08 31 68 00 4d 85 e4 44 8b 4b 08 74 5e <45> 8b 84 24 88 03 00 00 49 8d 8c 24 60 05 00 00 8b 53 04 48 89
         RIP  [<ffffffff810d6053>] spin_dump+0x53/0xc0
          RSP <ffff88003750fd68>
         ---[ end trace 783ebb76612867a0 ]---
         NMI watchdog: BUG: soft lockup - CPU#3 stuck for 22s! [test:18053]
         Modules linked in: 8021q mrp garp stp llc nf_conntrack_ipv4 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables binfmt_misc ppdev input_leds joydev parport_pc parport floppy serio_raw virtio_balloon virtio_rng virtio_console virtio_net iosf_mbi crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcspkr qxl ttm drm_kms_helper drm snd_hda_codec_generic i2c_piix4 snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd soundcore crc32c_intel virtio_pci virtio_ring virtio pata_acpi ata_generic [last unloaded: speedstep_lib]
         CPU: 3 PID: 18053 Comm: test Tainted: G      D         4.2.0-rc5+ #1
         Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014
         RIP: native_read_tsc+0x0/0x20
         Call Trace:
           ? delay_tsc+0x40/0x70
           __delay+0xf/0x20
           do_raw_spin_lock+0x96/0x140
           _raw_spin_lock+0xe/0x10
           sem_lock_and_putref+0x11/0x70
           SYSC_semtimedop+0x7bf/0x960
           ? handle_mm_fault+0xbf6/0x1880
           ? dequeue_task_fair+0x79/0x4a0
           ? __do_page_fault+0x19a/0x430
           ? kfree_debugcheck+0x16/0x40
           ? __do_page_fault+0x19a/0x430
           ? __audit_syscall_entry+0xa8/0x100
           ? do_audit_syscall_entry+0x66/0x70
           ? syscall_trace_enter_phase1+0x139/0x160
           SyS_semtimedop+0xe/0x10
           SyS_semop+0x10/0x20
           entry_SYSCALL_64_fastpath+0x12/0x71
         Code: 47 10 83 e8 01 85 c0 89 47 10 75 08 65 48 89 3d 1f 74 ff 7e c9 c3 0f 1f 44 00 00 55 48 89 e5 e8 87 17 04 00 66 90 c9 c3 0f 1f 00 <55> 48 89 e5 0f 31 89 c1 48 89 d0 48 c1 e0 20 89 c9 48 09 c8 c9
         Kernel panic - not syncing: softlockup: hung tasks
      
      I wasn't able to trigger any badness on a recent kernel without the
      proper config debugs enabled, however I have softlockup reports on some
      kernel versions, in the semaphore code, which are similar as above (the
      scenario is seen on some servers running IBM DB2 which uses semaphore
      syscalls).
      
      The patch here fixes the race against freeary, by acquiring or waiting
      on the sem_undo_list lock as necessary (exit_sem can race with freeary,
      while freeary sets un->semid to -1 and removes the same sem_undo from
      list_proc or when it removes the last sem_undo).
      
      After the patch I'm unable to reproduce the problem using the test case
      [1].
      
      [1] Test case used below:
      
          #include <stdio.h>
          #include <sys/types.h>
          #include <sys/ipc.h>
          #include <sys/sem.h>
          #include <sys/wait.h>
          #include <stdlib.h>
          #include <time.h>
          #include <unistd.h>
          #include <errno.h>
      
          #define NSEM 1
          #define NSET 5
      
          int sid[NSET];
      
          void thread()
          {
                  struct sembuf op;
                  int s;
                  uid_t pid = getuid();
      
                  s = rand() % NSET;
                  op.sem_num = pid % NSEM;
                  op.sem_op = 1;
                  op.sem_flg = SEM_UNDO;
      
                  semop(sid[s], &op, 1);
                  exit(EXIT_SUCCESS);
          }
      
          void create_set()
          {
                  int i, j;
                  pid_t p;
                  union {
                          int val;
                          struct semid_ds *buf;
                          unsigned short int *array;
                          struct seminfo *__buf;
                  } un;
      
                  /* Create and initialize semaphore set */
                  for (i = 0; i < NSET; i++) {
                          sid[i] = semget(IPC_PRIVATE , NSEM, 0644 | IPC_CREAT);
                          if (sid[i] < 0) {
                                  perror("semget");
                                  exit(EXIT_FAILURE);
                          }
                  }
                  un.val = 0;
                  for (i = 0; i < NSET; i++) {
                          for (j = 0; j < NSEM; j++) {
                                  if (semctl(sid[i], j, SETVAL, un) < 0)
                                          perror("semctl");
                          }
                  }
      
                  /* Launch threads that operate on semaphore set */
                  for (i = 0; i < NSEM * NSET * NSET; i++) {
                          p = fork();
                          if (p < 0)
                                  perror("fork");
                          if (p == 0)
                                  thread();
                  }
      
                  /* Free semaphore set */
                  for (i = 0; i < NSET; i++) {
                          if (semctl(sid[i], NSEM, IPC_RMID))
                                  perror("IPC_RMID");
                  }
      
                  /* Wait for forked processes to exit */
                  while (wait(NULL)) {
                          if (errno == ECHILD)
                                  break;
                  };
          }
      
          int main(int argc, char **argv)
          {
                  pid_t p;
      
                  srand(time(NULL));
      
                  while (1) {
                          p = fork();
                          if (p < 0) {
                                  perror("fork");
                                  exit(EXIT_FAILURE);
                          }
                          if (p == 0) {
                                  create_set();
                                  goto end;
                          }
      
                          /* Wait for forked processes to exit */
                          while (wait(NULL)) {
                                  if (errno == ECHILD)
                                          break;
                          };
                  }
          end:
                  return 0;
          }
      
      [akpm@linux-foundation.org: use normal comment layout]
      Signed-off-by: default avatarHerton R. Krzesinski <herton@redhat.com>
      Acked-by: default avatarManfred Spraul <manfred@colorfullife.com>
      Cc: Davidlohr Bueso <dave@stgolabs.net>
      Cc: Rafael Aquini <aquini@redhat.com>
      CC: Aristeu Rozanski <aris@redhat.com>
      Cc: David Jeffery <djeffery@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      89055eb6
    • Wanpeng Li's avatar
      mm/hwpoison: fix page refcount of unknown non LRU page · fe192579
      Wanpeng Li authored
      commit 4f32be67 upstream.
      
      After trying to drain pages from pagevec/pageset, we try to get reference
      count of the page again, however, the reference count of the page is not
      reduced if the page is still not on LRU list.
      
      Fix it by adding the put_page() to drop the page reference which is from
      __get_any_page().
      Signed-off-by: default avatarWanpeng Li <wanpeng.li@hotmail.com>
      Acked-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      fe192579
    • Thomas Hellstrom's avatar
      drm/vmwgfx: Fix execbuf locking issues · 7cf9c385
      Thomas Hellstrom authored
      commit 3e04e2fe upstream.
      
      This addresses two issues that cause problems with viewperf maya-03 in
      situation with memory pressure.
      
      The first issue causes attempts to unreserve buffers if batched
      reservation fails due to, for example, a signal pending. While previously
      the ttm_eu api was resistant against this type of error, it is no longer
      and the lockdep code will complain about attempting to unreserve buffers
      that are not reserved. The issue is resolved by avoid calling
      ttm_eu_backoff_reservation in the buffer reserve error path.
      
      The second issue is that the binding_mutex may be held when user-space
      fence objects are created and hence during memory reclaims. This may cause
      recursive attempts to grab the binding mutex. The issue is resolved by not
      holding the binding mutex across fence creation and submission.
      Signed-off-by: default avatarThomas Hellstrom <thellstrom@vmware.com>
      Reviewed-by: default avatarSinclair Yeh <syeh@vmware.com>
      Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      7cf9c385
    • Horia Geant?'s avatar
      crypto: caam - fix memory corruption in ahash_final_ctx · c5509f8e
      Horia Geant? authored
      commit b310c178 upstream.
      
      When doing pointer operation for accessing the HW S/G table,
      a value representing number of entries (and not number of bytes)
      must be used.
      
      Fixes: 045e3678 ("crypto: caam - ahash hmac support")
      Signed-off-by: default avatarHoria Geant? <horia.geanta@freescale.com>
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      c5509f8e
    • Michael Walle's avatar
      EDAC, ppc4xx: Access mci->csrows array elements properly · 0e163872
      Michael Walle authored
      commit 5c16179b upstream.
      
      The commit
      
        de3910eb ("edac: change the mem allocation scheme to
      		 make Documentation/kobject.txt happy")
      
      changed the memory allocation for the csrows member. But ppc4xx_edac was
      forgotten in the patch. Fix it.
      Signed-off-by: default avatarMichael Walle <michael@walle.cc>
      Cc: linux-edac <linux-edac@vger.kernel.org>
      Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
      Link: http://lkml.kernel.org/r/1437469253-8611-1-git-send-email-michael@walle.ccSigned-off-by: default avatarBorislav Petkov <bp@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      0e163872
    • Martin K. Petersen's avatar
      sd: Fix maximum I/O size for BLOCK_PC requests · afd9b6bb
      Martin K. Petersen authored
      commit 4f258a46 upstream.
      
      Commit bcdb247c ("sd: Limit transfer length") clamped the maximum
      size of an I/O request to the MAXIMUM TRANSFER LENGTH field in the BLOCK
      LIMITS VPD. This had the unfortunate effect of also limiting the maximum
      size of non-filesystem requests sent to the device through sg/bsg.
      
      Avoid using blk_queue_max_hw_sectors() and set the max_sectors queue
      limit directly.
      
      Also update the comment in blk_limits_max_hw_sectors() to clarify that
      max_hw_sectors defines the limit for the I/O controller only.
      Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
      Reported-by: default avatarBrian King <brking@linux.vnet.ibm.com>
      Tested-by: default avatarBrian King <brking@linux.vnet.ibm.com>
      Signed-off-by: default avatarJames Bottomley <JBottomley@Odin.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      afd9b6bb
    • Bart Van Assche's avatar
      libfc: Fix fc_fcp_cleanup_each_cmd() · 4459e7bb
      Bart Van Assche authored
      commit 8f2777f5 upstream.
      
      Since fc_fcp_cleanup_cmd() can sleep this function must not
      be called while holding a spinlock. This patch avoids that
      fc_fcp_cleanup_each_cmd() triggers the following bug:
      
      BUG: scheduling while atomic: sg_reset/1512/0x00000202
      1 lock held by sg_reset/1512:
       #0:  (&(&fsp->scsi_pkt_lock)->rlock){+.-...}, at: [<ffffffffc0225cd5>] fc_fcp_cleanup_each_cmd.isra.21+0xa5/0x150 [libfc]
      Preemption disabled at:[<ffffffffc0225cd5>] fc_fcp_cleanup_each_cmd.isra.21+0xa5/0x150 [libfc]
      Call Trace:
       [<ffffffff816c612c>] dump_stack+0x4f/0x7b
       [<ffffffff810828bc>] __schedule_bug+0x6c/0xd0
       [<ffffffff816c87aa>] __schedule+0x71a/0xa10
       [<ffffffff816c8ad2>] schedule+0x32/0x80
       [<ffffffffc0217eac>] fc_seq_set_resp+0xac/0x100 [libfc]
       [<ffffffffc0218b11>] fc_exch_done+0x41/0x60 [libfc]
       [<ffffffffc0225cff>] fc_fcp_cleanup_each_cmd.isra.21+0xcf/0x150 [libfc]
       [<ffffffffc0225f43>] fc_eh_device_reset+0x1c3/0x270 [libfc]
       [<ffffffff814a2cc9>] scsi_try_bus_device_reset+0x29/0x60
       [<ffffffff814a3908>] scsi_ioctl_reset+0x258/0x2d0
       [<ffffffff814a2650>] scsi_ioctl+0x150/0x440
       [<ffffffff814b3a9d>] sd_ioctl+0xad/0x120
       [<ffffffff8132f266>] blkdev_ioctl+0x1b6/0x810
       [<ffffffff811da608>] block_ioctl+0x38/0x40
       [<ffffffff811b4e08>] do_vfs_ioctl+0x2f8/0x530
       [<ffffffff811b50c1>] SyS_ioctl+0x81/0xa0
       [<ffffffff816cf8b2>] system_call_fastpath+0x16/0x7a
      Signed-off-by: default avatarBart Van Assche <bart.vanassche@sandisk.com>
      Signed-off-by: default avatarVasu Dev <vasu.dev@intel.com>
      Signed-off-by: default avatarJames Bottomley <JBottomley@Odin.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      4459e7bb
    • Bart Van Assche's avatar
      libfc: Fix fc_exch_recv_req() error path · 6014e983
      Bart Van Assche authored
      commit f6979ade upstream.
      
      Due to patch "libfc: Do not invoke the response handler after
      fc_exch_done()" (commit ID 7030fd62) the lport_recv() call
      in fc_exch_recv_req() is passed a dangling pointer. Avoid this
      by moving the fc_frame_free() call from fc_invoke_resp() to its
      callers. This patch fixes the following crash:
      
      general protection fault: 0000 [#3] PREEMPT SMP
      RIP: fc_lport_recv_req+0x72/0x280 [libfc]
      Call Trace:
       fc_exch_recv+0x642/0xde0 [libfc]
       fcoe_percpu_receive_thread+0x46a/0x5ed [fcoe]
       kthread+0x10a/0x120
       ret_from_fork+0x42/0x70
      Signed-off-by: default avatarBart Van Assche <bart.vanassche@sandisk.com>
      Signed-off-by: default avatarVasu Dev <vasu.dev@intel.com>
      Signed-off-by: default avatarJames Bottomley <JBottomley@Odin.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      6014e983
    • John Soni Jose's avatar
      libiscsi: Fix host busy blocking during connection teardown · 9b656263
      John Soni Jose authored
      commit 660d0831 upstream.
      
      In case of hw iscsi offload, an host can have N-number of active
      connections. There can be IO's running on some connections which
      make host->host_busy always TRUE. Now if logout from a connection
      is tried then the code gets into an infinite loop as host->host_busy
      is always TRUE.
      
       iscsi_conn_teardown(....)
       {
         .........
          /*
           * Block until all in-progress commands for this connection
           * time out or fail.
           */
           for (;;) {
            spin_lock_irqsave(session->host->host_lock, flags);
            if (!atomic_read(&session->host->host_busy)) { /* OK for ERL == 0 */
      	      spin_unlock_irqrestore(session->host->host_lock, flags);
                    break;
            }
           spin_unlock_irqrestore(session->host->host_lock, flags);
           msleep_interruptible(500);
           iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
                       "host_busy %d host_failed %d\n",
      	          atomic_read(&session->host->host_busy),
      	          session->host->host_failed);
      
      	................
      	...............
           }
        }
      
      This is not an issue with software-iscsi/iser as each cxn is a separate
      host.
      
      Fix:
      Acquiring eh_mutex in iscsi_conn_teardown() before setting
      session->state = ISCSI_STATE_TERMINATE.
      Signed-off-by: default avatarJohn Soni Jose <sony.john@avagotech.com>
      Reviewed-by: default avatarMike Christie <michaelc@cs.wisc.edu>
      Reviewed-by: default avatarChris Leech <cleech@redhat.com>
      Signed-off-by: default avatarJames Bottomley <JBottomley@Odin.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      9b656263
    • Alex Deucher's avatar
      drm/radeon: add new OLAND pci id · b5a34a64
      Alex Deucher authored
      commit e037239e upstream.
      Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      b5a34a64
    • Joe Thornber's avatar
      dm btree: add ref counting ops for the leaves of top level btrees · b2fc032f
      Joe Thornber authored
      commit b0dc3c8b upstream.
      
      When using nested btrees, the top leaves of the top levels contain
      block addresses for the root of the next tree down.  If we shadow a
      shared leaf node the leaf values (sub tree roots) should be incremented
      accordingly.
      
      This is only an issue if there is metadata sharing in the top levels.
      Which only occurs if metadata snapshots are being used (as is possible
      with dm-thinp).  And could result in a block from the thinp metadata
      snap being reused early, thus corrupting the thinp metadata snap.
      Signed-off-by: default avatarJoe Thornber <ejt@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      [ luis: backported to 3.16:
        - dropped changes to remove_one() as suggested by Mike Snitzer ]
      Signed-off-by: default avatarLuis Henriques <luis.henriques@canonical.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      b2fc032f
    • Joe Thornber's avatar
      dm thin metadata: delete btrees when releasing metadata snapshot · 39a41d21
      Joe Thornber authored
      commit 7f518ad0 upstream.
      
      The device details and mapping trees were just being decremented
      before.  Now btree_del() is called to do a deep delete.
      Signed-off-by: default avatarJoe Thornber <ejt@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      39a41d21
    • Richard Weinberger's avatar
      localmodconfig: Use Kbuild files too · e304c7e1
      Richard Weinberger authored
      commit c0ddc8c7 upstream.
      
      In kbuild it is allowed to define objects in files named "Makefile"
      and "Kbuild".
      Currently localmodconfig reads objects only from "Makefile"s and misses
      modules like nouveau.
      
      Link: http://lkml.kernel.org/r/1437948415-16290-1-git-send-email-richard@nod.atReported-and-tested-by: default avatarLeonidas Spyropoulos <artafinde@gmail.com>
      Signed-off-by: default avatarRichard Weinberger <richard@nod.at>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      e304c7e1
    • Maarten Lankhorst's avatar
      drm/dp/mst: Remove port after removing connector. · 2e014d79
      Maarten Lankhorst authored
      commit 4772ff03 upstream.
      
      The port is removed synchronously, but the connector delayed.
      This causes a use after free which can cause a kernel BUG with
      slug_debug=FPZU. This is fixed by freeing the port after the
      connector.
      
      This fixes a regression introduced with
      6b8eeca6
      "drm/dp/mst: close deadlock in connector destruction."
      
      Cc: Dave Airlie <airlied@redhat.com>
      Signed-off-by: default avatarMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
      Reviewed-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
      Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      2e014d79
    • Alban Crequy's avatar
      cpuset: use trialcs->mems_allowed as a temp variable · 319f5fe0
      Alban Crequy authored
      commit 24ee3cf8 upstream.
      
      The comment says it's using trialcs->mems_allowed as a temp variable but
      it didn't match the code. Change the code to match the comment.
      
      This fixes an issue when writing in cpuset.mems when a sub-directory
      exists: we need to write several times for the information to persist:
      
      | root@alban:/sys/fs/cgroup/cpuset# mkdir footest9
      | root@alban:/sys/fs/cgroup/cpuset# cd footest9
      | root@alban:/sys/fs/cgroup/cpuset/footest9# mkdir aa
      | root@alban:/sys/fs/cgroup/cpuset/footest9# cat cpuset.mems
      |
      | root@alban:/sys/fs/cgroup/cpuset/footest9# echo 0 > cpuset.mems
      | root@alban:/sys/fs/cgroup/cpuset/footest9# cat cpuset.mems
      |
      | root@alban:/sys/fs/cgroup/cpuset/footest9# echo 0 > cpuset.mems
      | root@alban:/sys/fs/cgroup/cpuset/footest9# cat cpuset.mems
      | 0
      | root@alban:/sys/fs/cgroup/cpuset/footest9# cat aa/cpuset.mems
      |
      | root@alban:/sys/fs/cgroup/cpuset/footest9# echo 0 > aa/cpuset.mems
      | root@alban:/sys/fs/cgroup/cpuset/footest9# cat aa/cpuset.mems
      | 0
      | root@alban:/sys/fs/cgroup/cpuset/footest9#
      
      This should help to fix the following issue in Docker:
      https://github.com/opencontainers/runc/issues/133
      In some conditions, a Docker container needs to be started twice in
      order to work.
      Signed-off-by: default avatarAlban Crequy <alban@endocode.com>
      Tested-by: default avatarIago López Galeiras <iago@endocode.com>
      Acked-by: default avatarLi Zefan <lizefan@huawei.com>
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      319f5fe0
    • Jason A. Donenfeld's avatar
      x86/xen: build "Xen PV" APIC driver for domU as well · 162350ea
      Jason A. Donenfeld authored
      commit fc5fee86 upstream.
      
      It turns out that a PV domU also requires the "Xen PV" APIC
      driver. Otherwise, the flat driver is used and we get stuck in busy
      loops that never exit, such as in this stack trace:
      
      (gdb) target remote localhost:9999
      Remote debugging using localhost:9999
      __xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56
      56              while (native_apic_mem_read(APIC_ICR) & APIC_ICR_BUSY)
      (gdb) bt
       #0  __xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56
       #1  __default_send_IPI_shortcut (shortcut=<optimized out>,
      dest=<optimized out>, vector=<optimized out>) at
      ./arch/x86/include/asm/ipi.h:75
       #2  apic_send_IPI_self (vector=246) at arch/x86/kernel/apic/probe_64.c:54
       #3  0xffffffff81011336 in arch_irq_work_raise () at
      arch/x86/kernel/irq_work.c:47
       #4  0xffffffff8114990c in irq_work_queue (work=0xffff88000fc0e400) at
      kernel/irq_work.c:100
       #5  0xffffffff8110c29d in wake_up_klogd () at kernel/printk/printk.c:2633
       #6  0xffffffff8110ca60 in vprintk_emit (facility=0, level=<optimized
      out>, dict=0x0 <irq_stack_union>, dictlen=<optimized out>,
      fmt=<optimized out>, args=<optimized out>)
          at kernel/printk/printk.c:1778
       #7  0xffffffff816010c8 in printk (fmt=<optimized out>) at
      kernel/printk/printk.c:1868
       #8  0xffffffffc00013ea in ?? ()
       #9  0x0000000000000000 in ?? ()
      
      Mailing-list-thread: https://lkml.org/lkml/2015/8/4/755Signed-off-by: default avatarJason A. Donenfeld <Jason@zx2c4.com>
      Signed-off-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      162350ea
    • Haozhong Zhang's avatar
      KVM: x86: Use adjustment in guest cycles when handling MSR_IA32_TSC_ADJUST · ad1ec6b6
      Haozhong Zhang authored
      commit d7add054 upstream.
      
      When kvm_set_msr_common() handles a guest's write to
      MSR_IA32_TSC_ADJUST, it will calcuate an adjustment based on the data
      written by guest and then use it to adjust TSC offset by calling a
      call-back adjust_tsc_offset(). The 3rd parameter of adjust_tsc_offset()
      indicates whether the adjustment is in host TSC cycles or in guest TSC
      cycles. If SVM TSC scaling is enabled, adjust_tsc_offset()
      [i.e. svm_adjust_tsc_offset()] will first scale the adjustment;
      otherwise, it will just use the unscaled one. As the MSR write here
      comes from the guest, the adjustment is in guest TSC cycles. However,
      the current kvm_set_msr_common() uses it as a value in host TSC
      cycles (by using true as the 3rd parameter of adjust_tsc_offset()),
      which can result in an incorrect adjustment of TSC offset if SVM TSC
      scaling is enabled. This patch fixes this problem.
      Signed-off-by: default avatarHaozhong Zhang <haozhong.zhang@intel.com>
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      ad1ec6b6
    • Jan Kara's avatar
      fsnotify: fix oops in fsnotify_clear_marks_by_group_flags() · a84bea5f
      Jan Kara authored
      commit 8f2f3eb5 upstream.
      
      fsnotify_clear_marks_by_group_flags() can race with
      fsnotify_destroy_marks() so that when fsnotify_destroy_mark_locked()
      drops mark_mutex, a mark from the list iterated by
      fsnotify_clear_marks_by_group_flags() can be freed and thus the next
      entry pointer we have cached may become stale and we dereference free
      memory.
      
      Fix the problem by first moving marks to free to a special private list
      and then always free the first entry in the special list.  This method
      is safe even when entries from the list can disappear once we drop the
      lock.
      Signed-off-by: default avatarJan Kara <jack@suse.com>
      Reported-by: default avatarAshish Sangwan <a.sangwan@samsung.com>
      Reviewed-by: default avatarAshish Sangwan <a.sangwan@samsung.com>
      Cc: Lino Sanfilippo <LinoSanfilippo@gmx.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      a84bea5f
    • Joseph Qi's avatar
      ocfs2: fix BUG in ocfs2_downconvert_thread_do_work() · d8197e1e
      Joseph Qi authored
      commit 209f7512 upstream.
      
      The "BUG_ON(list_empty(&osb->blocked_lock_list))" in
      ocfs2_downconvert_thread_do_work can be triggered in the following case:
      
      ocfs2dc has firstly saved osb->blocked_lock_count to local varibale
      processed, and then processes the dentry lockres.  During the dentry
      put, it calls iput and then deletes rw, inode and open lockres from
      blocked list in ocfs2_mark_lockres_freeing.  And this causes the
      variable `processed' to not reflect the number of blocked lockres to be
      processed, which triggers the BUG.
      Signed-off-by: default avatarJoseph Qi <joseph.qi@huawei.com>
      Cc: Mark Fasheh <mfasheh@suse.com>
      Cc: Joel Becker <jlbec@evilplan.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      d8197e1e
    • Marcus Gelderie's avatar
      ipc: modify message queue accounting to not take kernel data structures into account · 0c92b3c7
      Marcus Gelderie authored
      commit de54b9ac upstream.
      
      A while back, the message queue implementation in the kernel was
      improved to use btrees to speed up retrieval of messages, in commit
      d6629859 ("ipc/mqueue: improve performance of send/recv").
      
      That patch introducing the improved kernel handling of message queues
      (using btrees) has, as a by-product, changed the meaning of the QSIZE
      field in the pseudo-file created for the queue.  Before, this field
      reflected the size of the user-data in the queue.  Since, it also takes
      kernel data structures into account.  For example, if 13 bytes of user
      data are in the queue, on my machine the file reports a size of 61
      bytes.
      
      There was some discussion on this topic before (for example
      https://lkml.org/lkml/2014/10/1/115).  Commenting on a th lkml, Michael
      Kerrisk gave the following background
      (https://lkml.org/lkml/2015/6/16/74):
      
          The pseudofiles in the mqueue filesystem (usually mounted at
          /dev/mqueue) expose fields with metadata describing a message
          queue. One of these fields, QSIZE, as originally implemented,
          showed the total number of bytes of user data in all messages in
          the message queue, and this feature was documented from the
          beginning in the mq_overview(7) page. In 3.5, some other (useful)
          work happened to break the user-space API in a couple of places,
          including the value exposed via QSIZE, which now includes a measure
          of kernel overhead bytes for the queue, a figure that renders QSIZE
          useless for its original purpose, since there's no way to deduce
          the number of overhead bytes consumed by the implementation.
          (The other user-space breakage was subsequently fixed.)
      
      This patch removes the accounting of kernel data structures in the
      queue.  Reporting the size of these data-structures in the QSIZE field
      was a breaking change (see Michael's comment above).  Without the QSIZE
      field reporting the total size of user-data in the queue, there is no
      way to deduce this number.
      
      It should be noted that the resource limit RLIMIT_MSGQUEUE is counted
      against the worst-case size of the queue (in both the old and the new
      implementation).  Therefore, the kernel overhead accounting in QSIZE is
      not necessary to help the user understand the limitations RLIMIT imposes
      on the processes.
      Signed-off-by: default avatarMarcus Gelderie <redmnic@gmail.com>
      Acked-by: default avatarDoug Ledford <dledford@redhat.com>
      Acked-by: default avatarMichael Kerrisk <mtk.manpages@gmail.com>
      Acked-by: default avatarDavidlohr Bueso <dbueso@suse.de>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: John Duffy <jb_duffy@btinternet.com>
      Cc: Arto Bendiken <arto@bendiken.net>
      Cc: Manfred Spraul <manfred@colorfullife.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      0c92b3c7
    • David Daney's avatar
      MIPS: Make set_pte() SMP safe. · 18738241
      David Daney authored
      commit 46011e6e upstream.
      
      On MIPS the GLOBAL bit of the PTE must have the same value in any
      aligned pair of PTEs.  These pairs of PTEs are referred to as
      "buddies".  In a SMP system is is possible for two CPUs to be calling
      set_pte() on adjacent PTEs at the same time.  There is a race between
      setting the PTE and a different CPU setting the GLOBAL bit in its
      buddy PTE.
      
      This race can be observed when multiple CPUs are executing
      vmap()/vfree() at the same time.
      
      Make setting the buddy PTE's GLOBAL bit an atomic operation to close
      the race condition.
      
      The case of CONFIG_64BIT_PHYS_ADDR && CONFIG_CPU_MIPS32 is *not*
      handled.
      Signed-off-by: default avatarDavid Daney <david.daney@cavium.com>
      Cc: linux-mips@linux-mips.org
      Patchwork: https://patchwork.linux-mips.org/patch/10835/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      18738241
    • Michal Hocko's avatar
      mm, vmscan: Do not wait for page writeback for GFP_NOFS allocations · 2a007f12
      Michal Hocko authored
      commit ecf5fc6e upstream.
      
      Nikolay has reported a hang when a memcg reclaim got stuck with the
      following backtrace:
      
      PID: 18308  TASK: ffff883d7c9b0a30  CPU: 1   COMMAND: "rsync"
        #0 __schedule at ffffffff815ab152
        #1 schedule at ffffffff815ab76e
        #2 schedule_timeout at ffffffff815ae5e5
        #3 io_schedule_timeout at ffffffff815aad6a
        #4 bit_wait_io at ffffffff815abfc6
        #5 __wait_on_bit at ffffffff815abda5
        #6 wait_on_page_bit at ffffffff8111fd4f
        #7 shrink_page_list at ffffffff81135445
        #8 shrink_inactive_list at ffffffff81135845
        #9 shrink_lruvec at ffffffff81135ead
       #10 shrink_zone at ffffffff811360c3
       #11 shrink_zones at ffffffff81136eff
       #12 do_try_to_free_pages at ffffffff8113712f
       #13 try_to_free_mem_cgroup_pages at ffffffff811372be
       #14 try_charge at ffffffff81189423
       #15 mem_cgroup_try_charge at ffffffff8118c6f5
       #16 __add_to_page_cache_locked at ffffffff8112137d
       #17 add_to_page_cache_lru at ffffffff81121618
       #18 pagecache_get_page at ffffffff8112170b
       #19 grow_dev_page at ffffffff811c8297
       #20 __getblk_slow at ffffffff811c91d6
       #21 __getblk_gfp at ffffffff811c92c1
       #22 ext4_ext_grow_indepth at ffffffff8124565c
       #23 ext4_ext_create_new_leaf at ffffffff81246ca8
       #24 ext4_ext_insert_extent at ffffffff81246f09
       #25 ext4_ext_map_blocks at ffffffff8124a848
       #26 ext4_map_blocks at ffffffff8121a5b7
       #27 mpage_map_one_extent at ffffffff8121b1fa
       #28 mpage_map_and_submit_extent at ffffffff8121f07b
       #29 ext4_writepages at ffffffff8121f6d5
       #30 do_writepages at ffffffff8112c490
       #31 __filemap_fdatawrite_range at ffffffff81120199
       #32 filemap_flush at ffffffff8112041c
       #33 ext4_alloc_da_blocks at ffffffff81219da1
       #34 ext4_rename at ffffffff81229b91
       #35 ext4_rename2 at ffffffff81229e32
       #36 vfs_rename at ffffffff811a08a5
       #37 SYSC_renameat2 at ffffffff811a3ffc
       #38 sys_renameat2 at ffffffff811a408e
       #39 sys_rename at ffffffff8119e51e
       #40 system_call_fastpath at ffffffff815afa89
      
      Dave Chinner has properly pointed out that this is a deadlock in the
      reclaim code because ext4 doesn't submit pages which are marked by
      PG_writeback right away.
      
      The heuristic was introduced by commit e62e384e ("memcg: prevent OOM
      with too many dirty pages") and it was applied only when may_enter_fs
      was specified.  The code has been changed by c3b94f44 ("memcg:
      further prevent OOM with too many dirty pages") which has removed the
      __GFP_FS restriction with a reasoning that we do not get into the fs
      code.  But this is not sufficient apparently because the fs doesn't
      necessarily submit pages marked PG_writeback for IO right away.
      
      ext4_bio_write_page calls io_submit_add_bh but that doesn't necessarily
      submit the bio.  Instead it tries to map more pages into the bio and
      mpage_map_one_extent might trigger memcg charge which might end up
      waiting on a page which is marked PG_writeback but hasn't been submitted
      yet so we would end up waiting for something that never finishes.
      
      Fix this issue by replacing __GFP_IO by may_enter_fs check (for case 2)
      before we go to wait on the writeback.  The page fault path, which is
      the only path that triggers memcg oom killer since 3.12, shouldn't
      require GFP_NOFS and so we shouldn't reintroduce the premature OOM
      killer issue which was originally addressed by the heuristic.
      
      As per David Chinner the xfs is doing similar thing since 2.6.15 already
      so ext4 is not the only affected filesystem.  Moreover he notes:
      
      : For example: IO completion might require unwritten extent conversion
      : which executes filesystem transactions and GFP_NOFS allocations. The
      : writeback flag on the pages can not be cleared until unwritten
      : extent conversion completes. Hence memory reclaim cannot wait on
      : page writeback to complete in GFP_NOFS context because it is not
      : safe to do so, memcg reclaim or otherwise.
      
      [tytso@mit.edu: corrected the control flow]
      Fixes: c3b94f44 ("memcg: further prevent OOM with too many dirty pages")
      Reported-by: default avatarNikolay Borisov <kernel@kyup.com>
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.cz>
      Signed-off-by: default avatarHugh Dickins <hughd@google.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      [ luis: backported to 3.16: used Hugh's backport for 4.1 ]
      Signed-off-by: default avatarLuis Henriques <luis.henriques@canonical.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      2a007f12
    • Takashi Sakamoto's avatar
      ALSA: fireworks/firewire-lib: add support for recent firmware quirk · 382bf90c
      Takashi Sakamoto authored
      commit 18f5ed36 upstream.
      
      Fireworks uses TSB43CB43(IceLynx-Micro) as its IEC 61883-1/6 interface.
      This chip includes ARM7 core, and loads and runs program. The firmware
      is stored in on-board memory and loaded every powering-on from it.
      
      Echo Audio ships several versions of firmwares for each model. These
      firmwares have each quirk and the quirk changes a sequence of packets.
      
      As long as I investigated, AudioFire2/AudioFire4/AudioFirePre8 have a
      quirk to transfer a first packet with 0x02 in its dbc field. This causes
      ALSA Fireworks driver to detect discontinuity. In this case, firmware
      version 5.7.0, 5.7.3 and 5.8.0 are used.
      
      Payload  CIP      CIP
      quadlets header1  header2
      02       00050002 90ffffff <-
      42       0005000a 90013000
      42       00050012 90014400
      42       0005001a 90015800
      02       0005001a 90ffffff
      42       00050022 90019000
      42       0005002a 9001a400
      42       00050032 9001b800
      02       00050032 90ffffff
      42       0005003a 9001d000
      42       00050042 9001e400
      42       0005004a 9001f800
      02       0005004a 90ffffff
      (AudioFire2 with firmware version 5.7.)
      
      $ dmesg
      snd-fireworks fw1.0: Detect discontinuity of CIP: 00 02
      
      These models, AudioFire8 (since Jul 2009 ) and Gibson Robot Interface
      Pack series uses the same ARM binary as their firmware. Thus, this
      quirk may be observed among them.
      
      This commit adds a new member for AMDTP structure. This member represents
      the value of dbc field in a first AMDTP packet. Drivers can set it with
      a preferred value according to model's quirk.
      Tested-by: default avatarJohannes Oertei <johannes.oertel@uni-due.de>
      Signed-off-by: default avatarTakashi Sakamoto <o-takashi@sakamocchi.jp>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      382bf90c
  2. 21 Sep, 2015 9 commits