1. 13 12月, 2015 1 次提交
  2. 12 12月, 2015 1 次提交
    • M
      parisc iommu: fix panic due to trying to allocate too large region · e46e31a3
      Mikulas Patocka 提交于
      When using the Promise TX2+ SATA controller on PA-RISC, the system often
      crashes with kernel panic, for example just writing data with the dd
      utility will make it crash.
      
      Kernel panic - not syncing: drivers/parisc/sba_iommu.c: I/O MMU @ 000000000000a000 is out of mapping resources
      
      CPU: 0 PID: 18442 Comm: mkspadfs Not tainted 4.4.0-rc2 #2
      Backtrace:
       [<000000004021497c>] show_stack+0x14/0x20
       [<0000000040410bf0>] dump_stack+0x88/0x100
       [<000000004023978c>] panic+0x124/0x360
       [<0000000040452c18>] sba_alloc_range+0x698/0x6a0
       [<0000000040453150>] sba_map_sg+0x260/0x5b8
       [<000000000c18dbb4>] ata_qc_issue+0x264/0x4a8 [libata]
       [<000000000c19535c>] ata_scsi_translate+0xe4/0x220 [libata]
       [<000000000c19a93c>] ata_scsi_queuecmd+0xbc/0x320 [libata]
       [<0000000040499bbc>] scsi_dispatch_cmd+0xfc/0x130
       [<000000004049da34>] scsi_request_fn+0x6e4/0x970
       [<00000000403e95a8>] __blk_run_queue+0x40/0x60
       [<00000000403e9d8c>] blk_run_queue+0x3c/0x68
       [<000000004049a534>] scsi_run_queue+0x2a4/0x360
       [<000000004049be68>] scsi_end_request+0x1a8/0x238
       [<000000004049de84>] scsi_io_completion+0xfc/0x688
       [<0000000040493c74>] scsi_finish_command+0x17c/0x1d0
      
      The cause of the crash is not exhaustion of the IOMMU space, there is
      plenty of free pages. The function sba_alloc_range is called with size
      0x11000, thus the pages_needed variable is 0x11. The function
      sba_search_bitmap is called with bits_wanted 0x11 and boundary size is
      0x10 (because dma_get_seg_boundary(dev) returns 0xffff).
      
      The function sba_search_bitmap attempts to allocate 17 pages that must not
      cross 16-page boundary - it can't satisfy this requirement
      (iommu_is_span_boundary always returns true) and fails even if there are
      many free entries in the IOMMU space.
      
      How did it happen that we try to allocate 17 pages that don't cross
      16-page boundary? The cause is in the function iommu_coalesce_chunks. This
      function tries to coalesce adjacent entries in the scatterlist. The
      function does several checks if it may coalesce one entry with the next,
      one of those checks is this:
      
      	if (startsg->length + dma_len > max_seg_size)
      		break;
      
      When it finishes coalescing adjacent entries, it allocates the mapping:
      
      sg_dma_len(contig_sg) = dma_len;
      dma_len = ALIGN(dma_len + dma_offset, IOVP_SIZE);
      sg_dma_address(contig_sg) =
      	PIDE_FLAG
      	| (iommu_alloc_range(ioc, dev, dma_len) << IOVP_SHIFT)
      	| dma_offset;
      
      It is possible that (startsg->length + dma_len > max_seg_size) is false
      (we are just near the 0x10000 max_seg_size boundary), so the funcion
      decides to coalesce this entry with the next entry. When the coalescing
      succeeds, the function performs
      	dma_len = ALIGN(dma_len + dma_offset, IOVP_SIZE);
      And now, because of non-zero dma_offset, dma_len is greater than 0x10000.
      iommu_alloc_range (a pointer to sba_alloc_range) is called and it attempts
      to allocate 17 pages for a device that must not cross 16-page boundary.
      
      To fix the bug, we must make sure that dma_len after addition of
      dma_offset and alignment doesn't cross the segment boundary. I.e. change
      	if (startsg->length + dma_len > max_seg_size)
      		break;
      to
      	if (ALIGN(dma_len + dma_offset + startsg->length, IOVP_SIZE) > max_seg_size)
      		break;
      
      This patch makes this change (it precalculates max_seg_boundary at the
      beginning of the function iommu_coalesce_chunks). I also added a check
      that the mapping length doesn't exceed dma_get_seg_boundary(dev) (it is
      not needed for Promise TX2+ SATA, but it may be needed for other devices
      that have dma_get_seg_boundary lower than dma_get_max_seg_size).
      Signed-off-by: NMikulas Patocka <mpatocka@redhat.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: NHelge Deller <deller@gmx.de>
      e46e31a3
  3. 11 12月, 2015 1 次提交
  4. 10 12月, 2015 4 次提交
    • J
      dm btree: fix bufio buffer leaks in dm_btree_del() error path · ed8b45a3
      Joe Thornber 提交于
      If dm_btree_del()'s call to push_frame() fails, e.g. due to
      btree_node_validator finding invalid metadata, the dm_btree_del() error
      path must unlock all frames (which have active dm-bufio buffers) that
      were pushed onto the del_stack.
      
      Otherwise, dm_bufio_client_destroy() will BUG_ON() because dm-bufio
      buffers have leaked, e.g.:
        device-mapper: bufio: leaked buffer 3, hold count 1, list 0
      Signed-off-by: NJoe Thornber <ejt@redhat.com>
      Signed-off-by: NMike Snitzer <snitzer@redhat.com>
      Cc: stable@vger.kernel.org
      ed8b45a3
    • J
      ipmi: move timer init to before irq is setup · 27f972d3
      Jan Stancek 提交于
      We encountered a panic on boot in ipmi_si on a dell per320 due to an
      uninitialized timer as follows.
      
      static int smi_start_processing(void       *send_info,
                                      ipmi_smi_t intf)
      {
              /* Try to claim any interrupts. */
              if (new_smi->irq_setup)
                      new_smi->irq_setup(new_smi);
      
       --> IRQ arrives here and irq handler tries to modify uninitialized timer
      
          which triggers BUG_ON(!timer->function) in __mod_timer().
      
       Call Trace:
         <IRQ>
         [<ffffffffa0532617>] start_new_msg+0x47/0x80 [ipmi_si]
         [<ffffffffa053269e>] start_check_enables+0x4e/0x60 [ipmi_si]
         [<ffffffffa0532bd8>] smi_event_handler+0x1e8/0x640 [ipmi_si]
         [<ffffffff810f5584>] ? __rcu_process_callbacks+0x54/0x350
         [<ffffffffa053327c>] si_irq_handler+0x3c/0x60 [ipmi_si]
         [<ffffffff810efaf0>] handle_IRQ_event+0x60/0x170
         [<ffffffff810f245e>] handle_edge_irq+0xde/0x180
         [<ffffffff8100fc59>] handle_irq+0x49/0xa0
         [<ffffffff8154643c>] do_IRQ+0x6c/0xf0
         [<ffffffff8100ba53>] ret_from_intr+0x0/0x11
      
              /* Set up the timer that drives the interface. */
              setup_timer(&new_smi->si_timer, smi_timeout, (long)new_smi);
      
      The following patch fixes the problem.
      
      To: Openipmi-developer@lists.sourceforge.net
      To: Corey Minyard <minyard@acm.org>
      CC: linux-kernel@vger.kernel.org
      Signed-off-by: NJan Stancek <jstancek@redhat.com>
      Signed-off-by: NTony Camuso <tcamuso@redhat.com>
      Signed-off-by: NCorey Minyard <cminyard@mvista.com>
      Cc: stable@vger.kernel.org # Applies cleanly to 3.10-, needs small rework before
      27f972d3
    • J
      dm space map metadata: fix ref counting bug when bootstrapping a new space map · 50dd842a
      Joe Thornber 提交于
      When applying block operations (BOPs) do not remove them from the
      uncommitted BOP ring-buffer until after they've been applied -- in case
      we recurse.
      
      Also, perform BOP_INC operation, in dm_sm_metadata_create() and
      sm_metadata_extend(), in terms of the uncommitted BOP ring-buffer rather
      than using direct calls to sm_ll_inc().
      Signed-off-by: NJoe Thornber <ejt@redhat.com>
      Signed-off-by: NMike Snitzer <snitzer@redhat.com>
      Cc: stable@vger.kernel.org
      50dd842a
    • J
      dm thin metadata: fix bug when taking a metadata snapshot · 49e99fc7
      Joe Thornber 提交于
      When you take a metadata snapshot the btree roots for the mapping and
      details tree need to have their reference counts incremented so they
      persist for the lifetime of the metadata snap.
      
      The roots being incremented were those currently written in the
      superblock, which could possibly be out of date if concurrent IO is
      triggering new mappings, breaking of sharing, etc.
      
      Fix this by performing a commit with the metadata lock held while taking
      a metadata snapshot.
      Signed-off-by: NJoe Thornber <ejt@redhat.com>
      Signed-off-by: NMike Snitzer <snitzer@redhat.com>
      Cc: stable@vger.kernel.org
      49e99fc7
  5. 09 12月, 2015 14 次提交
  6. 08 12月, 2015 19 次提交