- 30 10月, 2017 22 次提交
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由 Satoru Takeuchi 提交于
Signed-off-by: NSatoru Takeuchi <satoru.takeuchi@gmail.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Colin Ian King 提交于
There are checks on fs_info in __btrfs_panic to avoid dereferencing a null fs_info, however, there is a call to btrfs_crit that may also dereference a null fs_info. Fix this by adding a check to see if fs_info is null and only print the s_id if fs_info is non-null. Detected by CoverityScan CID#401973 ("Dereference after null check") Fixes: efe120a0 ("Btrfs: convert printk to btrfs_ and fix BTRFS prefix") Signed-off-by: NColin Ian King <colin.king@canonical.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Christos Gkekas 提交于
The value of variable 'can_recover' is never used after being set, thus it should be removed, as it was never used since the first commit 68a7342c ("Btrfs: cleanup orphaned root orphan item"). Signed-off-by: NChristos Gkekas <chris.gekas@gmail.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Christophe JAILLET 提交于
If 'btrfs_alloc_path()' fails, we must free the resources already allocated, as done in the other error handling paths in this function. Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: NQu Wenruo <quwenruo.btrfs@gmx.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Nikolay Borisov 提交于
__link_block_group is called from only 2 places and at each call site the space_info being passed is the same as the space info assigned to the passed cache struct. Let's remove the redundant argument and make the function reference the space_info from the passed block_group_cache. No functional changes Signed-off-by: NNikolay Borisov <nborisov@suse.com> Reviewed-by: NJosef Bacik <jbacik@fb.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> [ renamed to link_block_group ] Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Nikolay Borisov 提交于
Currently the code executes add_extent_mapping and if it is successful it links the new mapping, it then proceeds to unlock the extent mapping tree and check for failure and handle them. Instead, rework the code to only perform a single check if add_extent_mapping has failed and handle it, otherwise the code continues in a linear fashion. No functional changes Signed-off-by: NNikolay Borisov <nborisov@suse.com> Reviewed-by: NJosef Bacik <jbacik@fb.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Nikolay Borisov 提交于
Introduced by 5a5f79b5 ("Btrfs: allow unaligned DIO") and never used. The buffered fallback from unaligned DIO works as expected. Signed-off-by: NNikolay Borisov <nborisov@suse.com> Reviewed-by: NTimofey Titovets <nefelim4ag@gmail.com> Reviewed-by: NJosef Bacik <jbacik@fb.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Nikolay Borisov 提交于
btrfs_changed_cb_t represents the signature of the callback being passed to btrfs_compare_trees. Currently there is only one such callback, namely changed_cb in send.c. This function doesn't really uses the first 2 parameters, i.e. the roots. Since there are not other functions implementing the btrfs_changed_cb_t let's remove the unused parameters from the prototype and implementation. Signed-off-by: NNikolay Borisov <nborisov@suse.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Reviewed-by: NJosef Bacik <jbacik@fb.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Nikolay Borisov 提交于
iterate_dir_item:found_key - introduced in 31db9f7c ("Btrfs: introduce BTRFS_IOC_SEND for btrfs send/receive"), yet never used. record_ref:num - ditto This is a first pass with the low-hanging fruit. There are still quite a few unsued parameters in some function which have to abide by a callback interface. Signed-off-by: NNikolay Borisov <nborisov@suse.com> Reviewed-by: NJosef Bacik <jbacik@fb.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Nikolay Borisov 提交于
Src was initially part of 31ff1cd2 ("Btrfs: Copy into the log tree in big batches"), however 16e7549f ("Btrfs: incompatible format change to remove hole extents") changed parameters passed to copy_items which made the src variable redundant. Signed-off-by: NNikolay Borisov <nborisov@suse.com> Reviewed-by: NTimofey Titovets <nefelim4ag@gmail.com> Reviewed-by: NJosef Bacik <jbacik@fb.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Liu Bo 提交于
While we submit direct writes, if the inode is flagged with nodatasum, there's no benefit to submit asynchronously, because a) we don't have to calculate checksum across processors, b) and direct IO has started a plug, but async submit makes us queue IO on each device's scheduled IO list instead of DIO's plug list, so that IOs get much less merges in general. Lets use sync submit for nodatasum inodes. Signed-off-by: NLiu Bo <bo.li.liu@oracle.com> Reviewed-by: NJosef Bacik <jbacik@fb.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Liu Bo 提交于
After mapping block with BTRFS_MAP_WRITE, parities have been sorted to the end position, so this search can start from the first parity stripe. Signed-off-by: NLiu Bo <bo.li.liu@oracle.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> [ copied changelog as a comment ] Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Anand Jain 提交于
We didn't copy fsid to struct super_block.s_uuid so Overlay disables index feature with btrfs as the lower FS. kernel: overlayfs: fs on '/lower' does not support file handles, falling back to index=off. Fix this by publishing the fsid through struct super_block.s_uuid. [ dsterba: I think that setting s_uuid is the last missing bit. Overlay needs the file handle encoding support from the lower filesystem, which is supported. Filling the whole filesystem id is correct, the subvolume id is encoded in the file handle buffer from inside btrfs_encode_fh. ] Signed-off-by: NAnand Jain <anand.jain@oracle.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Omar Sandoval 提交于
Signed-off-by: NOmar Sandoval <osandov@fb.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Omar Sandoval 提交于
These aren't used outside of volumes.c. Signed-off-by: NOmar Sandoval <osandov@fb.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Anand Jain 提交于
So that perf can show the state symbol. Signed-off-by: NAnand Jain <anand.jain@oracle.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Nikolay Borisov 提交于
Some static functions are needlessly forward declared. Let's remove those declarations since they add no value. Signed-off-by: NNikolay Borisov <nborisov@suse.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Liu Bo 提交于
Both wait_for_commit() and wait_for_writer() are checking the condition out of the mutex lock. This refactors code a bit to be lock safe. Signed-off-by: NLiu Bo <bo.li.liu@oracle.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Liu Bo 提交于
Since TASK_UNINTERRUPTIBLE has been used here, wait_event() can do the same job. Signed-off-by: NLiu Bo <bo.li.liu@oracle.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Liu Bo 提交于
If we're still going to wait after schedule(), we don't have to do finish_wait() to remove our %wait_queue_entry since prepare_to_wait() won't add the same %wait_queue_entry twice. Signed-off-by: NLiu Bo <bo.li.liu@oracle.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Liu Bo 提交于
Block layer has a limit on plug, ie. BLK_MAX_REQUEST_COUNT == 16, so we don't gain benefits by batching 64 bios here. Signed-off-by: NLiu Bo <bo.li.liu@oracle.com> Reviewed-by: NDavid Sterba <dsterba@suse.com> Signed-off-by: NDavid Sterba <dsterba@suse.com>
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由 Linus Torvalds 提交于
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- 29 10月, 2017 18 次提交
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git://git.kernel.org/pub/scm/linux/kernel/git/davem/net由 Linus Torvalds 提交于
Pull networking fixes from David Miller: 1) Fix route leak in xfrm_bundle_create(). 2) In mac80211, validate user rate mask before configuring it. From Johannes Berg. 3) Properly enforce memory limits in fair queueing code, from Toke Hoiland-Jorgensen. 4) Fix lockdep splat in inet_csk_route_req(), from Eric Dumazet. 5) Fix TSO header allocation and management in mvpp2 driver, from Yan Markman. 6) Don't take socket lock in BH handler in strparser code, from Tom Herbert. 7) Don't show sockets from other namespaces in AF_UNIX code, from Andrei Vagin. 8) Fix double free in error path of tap_open(), from Girish Moodalbail. 9) Fix TX map failure path in igb and ixgbe, from Jean-Philippe Brucker and Alexander Duyck. 10) Fix DCB mode programming in stmmac driver, from Jose Abreu. 11) Fix err_count handling in various tunnels (ipip, ip6_gre). From Xin Long. 12) Properly align SKB head before building SKB in tuntap, from Jason Wang. 13) Avoid matching qdiscs with a zero handle during lookups, from Cong Wang. 14) Fix various endianness bugs in sctp, from Xin Long. 15) Fix tc filter callback races and add selftests which trigger the problem, from Cong Wang. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (73 commits) selftests: Introduce a new test case to tc testsuite selftests: Introduce a new script to generate tc batch file net_sched: fix call_rcu() race on act_sample module removal net_sched: add rtnl assertion to tcf_exts_destroy() net_sched: use tcf_queue_work() in tcindex filter net_sched: use tcf_queue_work() in rsvp filter net_sched: use tcf_queue_work() in route filter net_sched: use tcf_queue_work() in u32 filter net_sched: use tcf_queue_work() in matchall filter net_sched: use tcf_queue_work() in fw filter net_sched: use tcf_queue_work() in flower filter net_sched: use tcf_queue_work() in flow filter net_sched: use tcf_queue_work() in cgroup filter net_sched: use tcf_queue_work() in bpf filter net_sched: use tcf_queue_work() in basic filter net_sched: introduce a workqueue for RCU callbacks of tc filter sctp: fix some type cast warnings introduced since very beginning sctp: fix a type cast warnings that causes a_rwnd gets the wrong value sctp: fix some type cast warnings introduced by transport rhashtable sctp: fix some type cast warnings introduced by stream reconf ...
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由 David S. Miller 提交于
Cong Wang says: ==================== net_sched: fix races with RCU callbacks Recently, the RCU callbacks used in TC filters and TC actions keep drawing my attention, they introduce at least 4 race condition bugs: 1. A simple one fixed by Daniel: commit c78e1746 Author: Daniel Borkmann <daniel@iogearbox.net> Date: Wed May 20 17:13:33 2015 +0200 net: sched: fix call_rcu() race on classifier module unloads 2. A very nasty one fixed by me: commit 1697c4bb Author: Cong Wang <xiyou.wangcong@gmail.com> Date: Mon Sep 11 16:33:32 2017 -0700 net_sched: carefully handle tcf_block_put() 3. Two more bugs found by Chris: https://patchwork.ozlabs.org/patch/826696/ https://patchwork.ozlabs.org/patch/826695/ Usually RCU callbacks are simple, however for TC filters and actions, they are complex because at least TC actions could be destroyed together with the TC filter in one callback. And RCU callbacks are invoked in BH context, without locking they are parallel too. All of these contribute to the cause of these nasty bugs. Alternatively, we could also: a) Introduce a spinlock to serialize these RCU callbacks. But as I said in commit 1697c4bb ("net_sched: carefully handle tcf_block_put()"), it is very hard to do because of tcf_chain_dump(). Potentially we need to do a lot of work to make it possible (if not impossible). b) Just get rid of these RCU callbacks, because they are not necessary at all, callers of these call_rcu() are all on slow paths and holding RTNL lock, so blocking is allowed in their contexts. However, David and Eric dislike adding synchronize_rcu() here. As suggested by Paul, we could defer the work to a workqueue and gain the permission of holding RTNL again without any performance impact, however, in tcf_block_put() we could have a deadlock when flushing workqueue while hodling RTNL lock, the trick here is to defer the work itself in workqueue and make it queued after all other works so that we keep the same ordering to avoid any use-after-free. Please see the first patch for details. Patch 1 introduces the infrastructure, patch 2~12 move each tc filter to the new tc filter workqueue, patch 13 adds an assertion to catch potential bugs like this, patch 14 closes another rcu callback race, patch 15 and patch 16 add new test cases. ==================== Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Chris Mi 提交于
In this patchset, we fixed a tc bug. This patch adds the test case that reproduces the bug. To run this test case, user should specify an existing NIC device: # sudo ./tdc.py -d enp4s0f0 This test case belongs to category "flower". If user doesn't specify a NIC device, the test cases belong to "flower" will not be run. In this test case, we create 1M filters and all filters share the same action. When destroying all filters, kernel should not panic. It takes about 18s to run it. Acked-by: NJamal Hadi Salim <jhs@mojatatu.com> Acked-by: NLucas Bates <lucasb@mojatatu.com> Signed-off-by: NChris Mi <chrism@mellanox.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Chris Mi 提交于
# ./tdc_batch.py -h usage: tdc_batch.py [-h] [-n NUMBER] [-o] [-s] [-p] device file TC batch file generator positional arguments: device device name file batch file name optional arguments: -h, --help show this help message and exit -n NUMBER, --number NUMBER how many lines in batch file -o, --skip_sw skip_sw (offload), by default skip_hw -s, --share_action all filters share the same action -p, --prio all filters have different prio Acked-by: NJamal Hadi Salim <jhs@mojatatu.com> Acked-by: NLucas Bates <lucasb@mojatatu.com> Signed-off-by: NChris Mi <chrism@mellanox.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
Similar to commit c78e1746 ("net: sched: fix call_rcu() race on classifier module unloads"), we need to wait for flying RCU callback tcf_sample_cleanup_rcu(). Cc: Yotam Gigi <yotamg@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
After previous patches, it is now safe to claim that tcf_exts_destroy() is always called with RTNL lock. Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
Defer the tcf_exts_destroy() in RCU callback to tc filter workqueue and get RTNL lock. Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Cong Wang 提交于
This patch introduces a dedicated workqueue for tc filters so that each tc filter's RCU callback could defer their action destroy work to this workqueue. The helper tcf_queue_work() is introduced for them to use. Because we hold RTNL lock when calling tcf_block_put(), we can not simply flush works inside it, therefore we have to defer it again to this workqueue and make sure all flying RCU callbacks have already queued their work before this one, in other words, to ensure this is the last one to execute to prevent any use-after-free. On the other hand, this makes tcf_block_put() ugly and harder to understand. Since David and Eric strongly dislike adding synchronize_rcu(), this is probably the only solution that could make everyone happy. Please also see the code comments below. Reported-by: NChris Mi <chrism@mellanox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jiri Pirko <jiri@resnulli.us> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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