9994677c96
Fix net reference counting in fl_change() and remove redundant call to
tcf_exts_get_net() from __fl_delete(). __fl_put() already tries to get net
before releasing exts and deallocating a filter, so this code caused flower
classifier to obtain net twice per filter that is being deleted.
Implementation of __fl_delete() called tcf_exts_get_net() to pass its
result as 'async' flag to fl_mask_put(). However, 'async' flag is redundant
and only complicates fl_mask_put() implementation. This functionality seems
to be copied from filter cleanup code, where it was added by Cong with
following explanation:
This patchset tries to fix the race between call_rcu() and
cleanup_net() again. Without holding the netns refcnt the
tc_action_net_exit() in netns workqueue could be called before
filter destroy works in tc filter workqueue. This patchset
moves the netns refcnt from tc actions to tcf_exts, without
breaking per-netns tc actions.
This doesn't apply to flower mask, which doesn't call any tc action code
during cleanup. Simplify fl_mask_put() by removing the flag parameter and
always use tcf_queue_work() to free mask objects.
Fixes: 061775583e35 ("net: sched: flower: introduce reference counting for filters")
Fixes: 1f17f7742eeb ("net: sched: flower: insert filter to ht before offloading it to hw")
Fixes: 05cd271fd61a ("cls_flower: Support multiple masks per priority")
Reported-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.