1. 15 6月, 2010 2 次提交
    • P
      rcu: add an rcu_dereference_index_check() · f5155b33
      Paul E. McKenney 提交于
      The sparse RCU-pointer checking relies on type magic that dereferences
      the pointer in question.  This does not work if the pointer is in fact
      an array index.  This commit therefore supplies a new RCU API that
      omits the sparse checking to continue to support rcu_dereference()
      on integers.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      f5155b33
    • M
      tree/tiny rcu: Add debug RCU head objects · 551d55a9
      Mathieu Desnoyers 提交于
      Helps finding racy users of call_rcu(), which results in hangs because list
      entries are overwritten and/or skipped.
      
      Changelog since v4:
      - Bissectability is now OK
      - Now generate a WARN_ON_ONCE() for non-initialized rcu_head passed to
        call_rcu(). Statically initialized objects are detected with
        object_is_static().
      - Rename rcu_head_init_on_stack to init_rcu_head_on_stack.
      - Remove init_rcu_head() completely.
      
      Changelog since v3:
      - Include comments from Lai Jiangshan
      
      This new patch version is based on the debugobjects with the newly introduced
      "active state" tracker.
      
      Non-initialized entries are all considered as "statically initialized". An
      activation fixup (triggered by call_rcu()) takes care of performing the debug
      object initialization without issuing any warning. Since we cannot increase the
      size of struct rcu_head, I don't see much room to put an identifier for
      statically initialized rcu_head structures. So for now, we have to live without
      "activation without explicit init" detection. But the main purpose of this debug
      option is to detect double-activations (double call_rcu() use of a rcu_head
      before the callback is executed), which is correctly addressed here.
      
      This also detects potential internal RCU callback corruption, which would cause
      the callbacks to be executed twice.
      Signed-off-by: NMathieu Desnoyers <mathieu.desnoyers@efficios.com>
      CC: David S. Miller <davem@davemloft.net>
      CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
      CC: akpm@linux-foundation.org
      CC: mingo@elte.hu
      CC: laijs@cn.fujitsu.com
      CC: dipankar@in.ibm.com
      CC: josh@joshtriplett.org
      CC: dvhltc@us.ibm.com
      CC: niv@us.ibm.com
      CC: tglx@linutronix.de
      CC: peterz@infradead.org
      CC: rostedt@goodmis.org
      CC: Valdis.Kletnieks@vt.edu
      CC: dhowells@redhat.com
      CC: eric.dumazet@gmail.com
      CC: Alexey Dobriyan <adobriyan@gmail.com>
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Reviewed-by: NLai Jiangshan <laijs@cn.fujitsu.com>
      551d55a9
  2. 11 6月, 2010 1 次提交
    • J
      net: deliver skbs on inactive slaves to exact matches · 597a264b
      John Fastabend 提交于
      Currently, the accelerated receive path for VLAN's will
      drop packets if the real device is an inactive slave and
      is not one of the special pkts tested for in
      skb_bond_should_drop().  This behavior is different then
      the non-accelerated path and for pkts over a bonded vlan.
      
      For example,
      
      vlanx -> bond0 -> ethx
      
      will be dropped in the vlan path and not delivered to any
      packet handlers at all.  However,
      
      bond0 -> vlanx -> ethx
      
      and
      
      bond0 -> ethx
      
      will be delivered to handlers that match the exact dev,
      because the VLAN path checks the real_dev which is not a
      slave and netif_recv_skb() doesn't drop frames but only
      delivers them to exact matches.
      
      This patch adds a sk_buff flag which is used for tagging
      skbs that would previously been dropped and allows the
      skb to continue to skb_netif_recv().  Here we add
      logic to check for the deliver_no_wcard flag and if it
      is set only deliver to handlers that match exactly.  This
      makes both paths above consistent and gives pkt handlers
      a way to identify skbs that come from inactive slaves.
      Without this patch in some configurations skbs will be
      delivered to handlers with exact matches and in others
      be dropped out right in the vlan path.
      
      I have tested the following 4 configurations in failover modes
      and load balancing modes.
      
      # bond0 -> ethx
      
      # vlanx -> bond0 -> ethx
      
      # bond0 -> vlanx -> ethx
      
      # bond0 -> ethx
                  |
        vlanx -> --
      Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      597a264b
  3. 09 6月, 2010 3 次提交
    • A
      misc: Fix allocation 'borrowed' by vhost_net · 79907d89
      Alan Cox 提交于
      10, 233 is allocated officially to /dev/kmview which is shipping in
      Ubuntu and Debian distributions.  vhost_net seem to have borrowed it
      without making a proper request and this causes regressions in the other
      distributions.
      
      vhost_net can use a dynamic minor so use that instead.  Also update the
      file with a comment to try and avoid future misunderstandings.
      
      cc: stable@kernel.org
      Signed-off-by: NAlan Cox <device@lanana.org>
      [ We should have caught this before 2.6.34 got released.  - Linus ]
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      79907d89
    • D
      writeback: pay attention to wbc->nr_to_write in write_cache_pages · 0b564927
      Dave Chinner 提交于
      If a filesystem writes more than one page in ->writepage, write_cache_pages
      fails to notice this and continues to attempt writeback when wbc->nr_to_write
      has gone negative - this trace was captured from XFS:
      
          wbc_writeback_start: towrt=1024
          wbc_writepage: towrt=1024
          wbc_writepage: towrt=0
          wbc_writepage: towrt=-1
          wbc_writepage: towrt=-5
          wbc_writepage: towrt=-21
          wbc_writepage: towrt=-85
      
      This has adverse effects on filesystem writeback behaviour. write_cache_pages()
      needs to terminate after a certain number of pages are written, not after a
      certain number of calls to ->writepage are made.  This is a regression
      introduced by 17bc6c30 ("vfs: Add
      no_nrwrite_index_update writeback control flag"), but cannot be reverted
      directly due to subsequent bug fixes that have gone in on top of it.
      Signed-off-by: NDave Chinner <dchinner@redhat.com>
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0b564927
    • O
      tracing: Fix null pointer deref with SEND_SIG_FORCED · b9b76dfa
      Oleg Nesterov 提交于
      BUG: unable to handle kernel NULL pointer dereference at
      	0000000000000006
      IP: [<ffffffff8107bd37>] ftrace_raw_event_signal_generate+0x87/0x140
      
      TP_STORE_SIGINFO() forgets about SEND_SIG_FORCED, fix.
      
      We should probably export is_si_special() and change TP_STORE_SIGINFO()
      to use it in the longer term.
      Signed-off-by: NOleg Nesterov <oleg@redhat.com>
      Acked-by: NRoland McGrath <roland@redhat.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: Masami Hiramatsu <mhiramat@redhat.com>
      Cc: 2.6.33.x-2.6.34.x <stable@kernel.org>
      LKML-Reference: <20100603213409.GA8307@redhat.com>
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      b9b76dfa
  4. 08 6月, 2010 2 次提交
  5. 05 6月, 2010 6 次提交
  6. 03 6月, 2010 5 次提交
  7. 02 6月, 2010 1 次提交
  8. 01 6月, 2010 15 次提交
  9. 31 5月, 2010 5 次提交