Eric Paris got following trace with a linux-next kernel
[ 14.203970] BUG: using smp_processor_id() in preemptible [00000000]
code: avahi-daemon/2093
[ 14.204025] caller is netif_rx+0xfa/0x110
[ 14.204035] Call Trace:
[ 14.204064] [<ffffffff81278fe5>] debug_smp_processor_id+0x105/0x110
[ 14.204070] [<ffffffff8142163a>] netif_rx+0xfa/0x110
[ 14.204090] [<ffffffff8145b631>] ip_dev_loopback_xmit+0x71/0xa0
[ 14.204095] [<ffffffff8145b892>] ip_mc_output+0x192/0x2c0
[ 14.204099] [<ffffffff8145d610>] ip_local_out+0x20/0x30
[ 14.204105] [<ffffffff8145d8ad>] ip_push_pending_frames+0x28d/0x3d0
[ 14.204119] [<ffffffff8147f1cc>] udp_push_pending_frames+0x14c/0x400
[ 14.204125] [<ffffffff814803fc>] udp_sendmsg+0x39c/0x790
[ 14.204137] [<ffffffff814891d5>] inet_sendmsg+0x45/0x80
[ 14.204149] [<ffffffff8140af91>] sock_sendmsg+0xf1/0x110
[ 14.204189] [<ffffffff8140dc6c>] sys_sendmsg+0x20c/0x380
[ 14.204233] [<ffffffff8100ad82>] system_call_fastpath+0x16/0x1b
While current linux-2.6 kernel doesnt emit this warning, bug is latent
and might cause unexpected failures.
ip_dev_loopback_xmit() runs in process context, preemption enabled, so
must call netif_rx_ni() instead of netif_rx(), to make sure that we
process pending software interrupt.
Same change for ip6_dev_loopback_xmit()
Reported-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When dev_pick_tx() caches tx queue_index on a socket, we must check
socket dst_entry matches skb one, or risk a crash later, as reported by
Denys Fedorysychenko, if old packets are in flight during a route
change, involving devices with different number of queues.
Bug introduced by commit a4ee3ce3
(net: Use sk_tx_queue_mapping for connected sockets)
Reported-by: Denys Fedorysychenko <nuclearcat@nuclearcat.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The following situation was observed in the field:
tap1 sends packets, tap2 does not consume them, as a result
tap1 can not be closed. This happens because
tun/tap devices can hang on to skbs undefinitely.
As noted by Herbert, possible solutions include a timeout followed by a
copy/change of ownership of the skb, or always copying/changing
ownership if we're going into a hostile device.
This patch implements the second approach.
Note: one issue still remaining is that since skbs
keep reference to tun socket and tun socket has a
reference to tun device, we won't flush backlog,
instead simply waiting for all skbs to get transmitted.
At least this is not user-triggerable, and
this was not reported in practice, my assumption is
other devices besides tap complete an skb
within finite time after it has been queued.
A possible solution for the second issue
would not to have socket reference the device,
instead, implement dev->destructor for tun, and
wait for all skbs to complete there, but this
needs some thought, probably too risky for 2.6.34.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Yan Vugenfirer <yvugenfi@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a fix for bug 572201 @ bugs.debian.org
This patch fixes the TX_LIMIT feature flag. The previous logic check
for TX_LIMIT2 also took into account a device that only had TX_LIMIT
set.
Reported-by: Stephen Mulcahu <stephen.mulcahy@deri.org>
Reported-by: Ben Huchings <ben@decadent.org.uk>
Signed-off-by: Ayaz Abdulla <aabdulla@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
smc91c92_cs:
* define multicast_table as unsigned char
* remove unnecessary "#ifndef final_version"
Signed-off-by: Ken Kawasaki <ken_kawasaki@spring.nifty.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
At this point optlen == sizeof(sfilter) but some compilers are dumb.
Reported-by: Németh Márton <nm127@freemail.h
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tx ring buffers after tx_ring->next_to_use are volatile and could
change, possibly causing a crash. Stop cleaning when we hit
tx_ring->next_to_use.
Signed-off-by: Terry Loftin <terry.loftin@hp.com>
Acked-by: Bruce Allan <bruce.w.allan@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add missing sg_init_table for sg_set_buf in virtio_net which
induced in defer skb patch.
Reported-by: Thomas Müller <thomas@mathtm.de>
Tested-by: Thomas Müller <thomas@mathtm.de>
Signed-off-by: Shirley Ma <xma@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 2626419ad5.
It causes regressions for people with IGB cards. Connection
requests don't complete etc. The true cause of the issue is
still not known, but we should sort this out in net-next-2.6
not net-2.6
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
IB/mlx4: Check correct variable for allocation failure
RDMA/nes: Correct cap.max_inline_data assignment in nes_query_qp()
RDMA/cm: Set num_paths when manually assigning path records
IB/cm: Fix device_create() return value check
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (34 commits)
cfq-iosched: Fix the incorrect timeslice accounting with forced_dispatch
loop: Update mtime when writing using aops
block: expose the statistics in blkio.time and blkio.sectors for the root cgroup
backing-dev: Handle class_create() failure
Block: Fix block/elevator.c elevator_get() off-by-one error
drbd: lc_element_by_index() never returns NULL
cciss: unlock on error path
cfq-iosched: Do not merge queues of BE and IDLE classes
cfq-iosched: Add additional blktrace log messages in CFQ for easier debugging
i2o: Remove the dangerous kobj_to_i2o_device macro
block: remove 16 bytes of padding from struct request on 64bits
cfq-iosched: fix a kbuild regression
block: make CONFIG_BLK_CGROUP visible
Remove GENHD_FL_DRIVERFS
block: Export max number of segments and max segment size in sysfs
block: Finalize conversion of block limits functions
block: Fix overrun in lcm() and move it to lib
vfs: improve writeback_inodes_wb()
paride: fix off-by-one test
drbd: fix al-to-on-disk-bitmap for 4k logical_block_size
...
* 'drm-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (29 commits)
drm/nouveau: bail out of auxch transaction if we repeatedly recieve defers
drm/nv50: implement gpio set/get routines
drm/nv50: parse/use some more de-magiced parts of gpio table entries
drm/nouveau: store raw gpio table entry in bios gpio structs
drm/nv40: Init some tiling-related PGRAPH state.
drm/nv50: Add NVA3 support in ctxprog/ctxvals generator.
drm/nv50: another dodgy DP hack
drm/nv50: punt hotplug irq handling out to workqueue
drm/nv50: preserve an unknown SOR_MODECTRL value for DP encoders
drm/nv50: Allow using the NVA3 new compute class.
drm/nv50: cleanup properly if PDISPLAY init fails
drm/nouveau: fixup the init failure paths some more
drm/nv50: fix instmem init on IGPs if stolen mem crosses 4GiB mark
drm/nv40: add LVDS table quirk for Dell Latitude D620
drm/nv40: rework lvds table parsing
drm/nouveau: detect vram amount once, and save the value
drm/nouveau: remove some unused members from drm_nouveau_private
drm/nouveau: Make use of TTM busy_placements.
drm/nv50: add more 0x100c80 flushy magic
drm/nv50: fix fbcon when framebuffer above 4GiB mark
...
The current algorithm will sometimes "detect" that
more chains are enabled than are really present in
the device because, for unknown reasons, the ucode
sends up all-zeroes signal values.
The simplest way of solving this is to restrict the
active chains mask to the chains we know are really
present on the device.
This fixes a bug with some devices where, since sometimes
more chains are enabled than really present, the system would hang.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
radix_tree_tag_get() is not safe to use concurrently with radix_tree_tag_set()
or radix_tree_tag_clear(). The problem is that the double tag_get() in
radix_tree_tag_get():
if (!tag_get(node, tag, offset))
saw_unset_tag = 1;
if (height == 1) {
int ret = tag_get(node, tag, offset);
may see the value change due to the action of set/clear. RCU is no protection
against this as no pointers are being changed, no nodes are being replaced
according to a COW protocol - set/clear alter the node directly.
The documentation in linux/radix-tree.h, however, says that
radix_tree_tag_get() is an exception to the rule that "any function modifying
the tree or tags (...) must exclude other modifications, and exclude any
functions reading the tree".
The problem is that the next statement in radix_tree_tag_get() checks that the
tag doesn't vary over time:
BUG_ON(ret && saw_unset_tag);
This has been seen happening in FS-Cache:
https://www.redhat.com/archives/linux-cachefs/2010-April/msg00013.html
To this end, remove the BUG_ON() from radix_tree_tag_get() and note in various
comments that the value of the tag may change whilst the RCU read lock is held,
and thus that the return value of radix_tree_tag_get() may not be relied upon
unless radix_tree_tag_set/clear() and radix_tree_delete() are excluded from
running concurrently with it.
Reported-by: Romain DEGEZ <romain.degez@smartjog.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As suggested by Linus, fix up kmem_ptr_validate() to handle non-kernel pointers
more graciously. The patch changes kmem_ptr_validate() to use the newly
introduced kern_ptr_validate() helper to check that a pointer is a valid kernel
pointer before we attempt to convert it into a 'struct page'.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
