lkml.org 
[lkml]   [2013]   [Jun]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    SubjectRe: [PATCH] vhost_net: clear msg.control for non-zerocopy case during tx
    From
    From: "Michael S. Tsirkin" <mst@redhat.com>
    Date: Wed, 5 Jun 2013 12:02:52 +0300

    > On Wed, Jun 05, 2013 at 03:40:46PM +0800, Jason Wang wrote:
    >> When we decide not use zero-copy, msg.control should be set to NULL otherwise
    >> macvtap/tap may set zerocopy callbacks which may decrease the kref of ubufs
    >> wrongly.
    >>
    >> Bug were introduced by commit cedb9bdce099206290a2bdd02ce47a7b253b6a84
    >> (vhost-net: skip head management if no outstanding).
    >>
    >> This solves the following warnings:
    >>
    >> WARNING: at include/linux/kref.h:47 handle_tx+0x477/0x4b0 [vhost_net]()
    >> Modules linked in: vhost_net macvtap macvlan tun nfsd exportfs bridge stp llc openvswitch kvm_amd kvm bnx2 megaraid_sas [last unloaded: tun]
    >> CPU: 5 PID: 8670 Comm: vhost-8668 Not tainted 3.10.0-rc2+ #1566
    >> Hardware name: Dell Inc. PowerEdge R715/00XHKG, BIOS 1.5.2 04/19/2011
    >> ffffffffa0198323 ffff88007c9ebd08 ffffffff81796b73 ffff88007c9ebd48
    >> ffffffff8103d66b 000000007b773e20 ffff8800779f0000 ffff8800779f43f0
    >> ffff8800779f8418 000000000000015c 0000000000000062 ffff88007c9ebd58
    >> Call Trace:
    >> [<ffffffff81796b73>] dump_stack+0x19/0x1e
    >> [<ffffffff8103d66b>] warn_slowpath_common+0x6b/0xa0
    >> [<ffffffff8103d6b5>] warn_slowpath_null+0x15/0x20
    >> [<ffffffffa0197627>] handle_tx+0x477/0x4b0 [vhost_net]
    >> [<ffffffffa0197690>] handle_tx_kick+0x10/0x20 [vhost_net]
    >> [<ffffffffa019541e>] vhost_worker+0xfe/0x1a0 [vhost_net]
    >> [<ffffffffa0195320>] ? vhost_attach_cgroups_work+0x30/0x30 [vhost_net]
    >> [<ffffffffa0195320>] ? vhost_attach_cgroups_work+0x30/0x30 [vhost_net]
    >> [<ffffffff81061f46>] kthread+0xc6/0xd0
    >> [<ffffffff81061e80>] ? kthread_freezable_should_stop+0x70/0x70
    >> [<ffffffff817a1aec>] ret_from_fork+0x7c/0xb0
    >> [<ffffffff81061e80>] ? kthread_freezable_should_stop+0x70/0x70
    >>
    >> Signed-off-by: Jason Wang <jasowang@redhat.com>
    >
    > Good catch.
    >
    > Acked-by: Michael S. Tsirkin <mst@redhat.com>
    >
    > This needs to go into stable as well.

    Applied and queued up for -stable.


    \
     
     \ /
      Last update: 2013-06-11 01:01    [W:3.744 / U:1.692 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site