netdev_upper_dev_link() is useful to manage lower/upper interfaces.
And this function internally validates looping, maximum depth.
All or most virtual interfaces that could have a real interface
(e.g. macsec, macvlan, ipvlan etc.) use lower/upper infrastructure.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to access the port list, the hsr_port_get_hsr() is used.
And this is protected by RTNL and RCU.
The hsr_fill_info(), hsr_check_carrier(), hsr_dev_open() and
hsr_get_max_mtu() are protected by RTNL.
So, rcu_read_lock() in these functions are not necessary.
The hsr_handle_frame() also uses rcu_read_lock() but this function
is called by packet path.
It's already protected by RCU.
So, the rcu_read_lock() in hsr_handle_frame() can be removed.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When HSR interface is sending a frame, it finds a node with
the destination ethernet address from the list.
If there is no node, it calls WARN_ONCE().
But, using WARN_ONCE() for this situation is a little bit overdoing.
So, in this patch, the netdev_err() is used instead.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If HSR uses the extack instead of netdev_info(), users can get
error messages immediately without any checking the kernel message.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If it uses debugfs_remove_recursive() instead of debugfs_remove(),
hsr_priv() doesn't need to have "node_tbl_file" pointer variable.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
node_db is traversed using list_for_each_entry_rcu
outside an RCU read-side critical section but under the protection
of hsr->list_lock.
Hence, add corresponding lockdep expression to silence false-positive
warnings, and harden RCU lists.
Signed-off-by: Amol Grover <frextrite@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It's never used after introduced. So maybe better to remove.
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Arvid Brodin <arvid.brodin@alten.se>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
The hsr_debugfs_rename prototype got an extra 'void' that needs to
be removed again:
In file included from /git/arm-soc/net/hsr/hsr_main.c:12:
net/hsr/hsr_main.h:194:20: error: two or more data types in declaration specifiers
static inline void void hsr_debugfs_rename(struct net_device *dev)
Fixes: 4c2d5e33dc ("hsr: rename debugfs file when interface name is changed")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The supervision frame is L2 frame.
When supervision frame is created, hsr module doesn't set network header.
If tap routine is enabled, dev_queue_xmit_nit() is called and it checks
network_header. If network_header pointer wasn't set(or invalid),
it resets network_header and warns.
In order to avoid unnecessary warning message, resetting network_header
is needed.
Test commands:
ip netns add nst
ip link add veth0 type veth peer name veth1
ip link add veth2 type veth peer name veth3
ip link set veth1 netns nst
ip link set veth3 netns nst
ip link set veth0 up
ip link set veth2 up
ip link add hsr0 type hsr slave1 veth0 slave2 veth2
ip a a 192.168.100.1/24 dev hsr0
ip link set hsr0 up
ip netns exec nst ip link set veth1 up
ip netns exec nst ip link set veth3 up
ip netns exec nst ip link add hsr1 type hsr slave1 veth1 slave2 veth3
ip netns exec nst ip a a 192.168.100.2/24 dev hsr1
ip netns exec nst ip link set hsr1 up
tcpdump -nei veth0
Splat looks like:
[ 175.852292][ C3] protocol 88fb is buggy, dev veth0
Fixes: f421436a59 ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hsr nodes are protected by RCU and there is no write side lock.
But node insertions and deletions could be being operated concurrently.
So write side locking is needed.
Test commands:
ip netns add nst
ip link add veth0 type veth peer name veth1
ip link add veth2 type veth peer name veth3
ip link set veth1 netns nst
ip link set veth3 netns nst
ip link set veth0 up
ip link set veth2 up
ip link add hsr0 type hsr slave1 veth0 slave2 veth2
ip a a 192.168.100.1/24 dev hsr0
ip link set hsr0 up
ip netns exec nst ip link set veth1 up
ip netns exec nst ip link set veth3 up
ip netns exec nst ip link add hsr1 type hsr slave1 veth1 slave2 veth3
ip netns exec nst ip a a 192.168.100.2/24 dev hsr1
ip netns exec nst ip link set hsr1 up
for i in {0..9}
do
for j in {0..9}
do
for k in {0..9}
do
for l in {0..9}
do
arping 192.168.100.2 -I hsr0 -s 00:01:3$i:4$j:5$k:6$l -c1 &
done
done
done
done
Splat looks like:
[ 236.066091][ T3286] list_add corruption. next->prev should be prev (ffff8880a5940300), but was ffff8880a5940d0.
[ 236.069617][ T3286] ------------[ cut here ]------------
[ 236.070545][ T3286] kernel BUG at lib/list_debug.c:25!
[ 236.071391][ T3286] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[ 236.072343][ T3286] CPU: 0 PID: 3286 Comm: arping Tainted: G W 5.5.0-rc1+ #209
[ 236.073463][ T3286] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 236.074695][ T3286] RIP: 0010:__list_add_valid+0x74/0xd0
[ 236.075499][ T3286] Code: 48 39 da 75 27 48 39 f5 74 36 48 39 dd 74 31 48 83 c4 08 b8 01 00 00 00 5b 5d c3 48 b
[ 236.078277][ T3286] RSP: 0018:ffff8880aaa97648 EFLAGS: 00010286
[ 236.086991][ T3286] RAX: 0000000000000075 RBX: ffff8880d4624c20 RCX: 0000000000000000
[ 236.088000][ T3286] RDX: 0000000000000075 RSI: 0000000000000008 RDI: ffffed1015552ebf
[ 236.098897][ T3286] RBP: ffff88809b53d200 R08: ffffed101b3c04f9 R09: ffffed101b3c04f9
[ 236.099960][ T3286] R10: 00000000308769a1 R11: ffffed101b3c04f8 R12: ffff8880d4624c28
[ 236.100974][ T3286] R13: ffff8880d4624c20 R14: 0000000040310100 R15: ffff8880ce17ee02
[ 236.138967][ T3286] FS: 00007f23479fa680(0000) GS:ffff8880d9c00000(0000) knlGS:0000000000000000
[ 236.144852][ T3286] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 236.145720][ T3286] CR2: 00007f4a14bab210 CR3: 00000000a61c6001 CR4: 00000000000606f0
[ 236.146776][ T3286] Call Trace:
[ 236.147222][ T3286] hsr_add_node+0x314/0x490 [hsr]
[ 236.153633][ T3286] hsr_forward_skb+0x2b6/0x1bc0 [hsr]
[ 236.154362][ T3286] ? rcu_read_lock_sched_held+0x90/0xc0
[ 236.155091][ T3286] ? rcu_read_lock_bh_held+0xa0/0xa0
[ 236.156607][ T3286] hsr_dev_xmit+0x70/0xd0 [hsr]
[ 236.157254][ T3286] dev_hard_start_xmit+0x160/0x740
[ 236.157941][ T3286] __dev_queue_xmit+0x1961/0x2e10
[ 236.158565][ T3286] ? netdev_core_pick_tx+0x2e0/0x2e0
[ ... ]
Reported-by: syzbot+3924327f9ad5f4d2b343@syzkaller.appspotmail.com
Fixes: f421436a59 ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hsr interface has own debugfs file, which name is same with interface name.
So, interface name is changed, debugfs file name should be changed too.
Fixes: fc4ecaeebd ("net: hsr: add debugfs support for display node list")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In current hsr code, when hsr interface is created, it creates debugfs
directory /sys/kernel/debug/<interface name>.
If there is same directory or file name in there, it fails.
In order to reduce possibility of failure of creation of debugfs,
this patch adds root directory.
Test commands:
ip link add dummy0 type dummy
ip link add dummy1 type dummy
ip link add hsr0 type hsr slave1 dummy0 slave2 dummy1
Before this patch:
/sys/kernel/debug/hsr0/node_table
After this patch:
/sys/kernel/debug/hsr/hsr0/node_table
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hsr_dev_finalize() is called to create new hsr interface.
There are some wrong error handling codes.
1. wrong checking return value of debugfs_create_{dir/file}.
These function doesn't return NULL. If error occurs in there,
it returns error pointer.
So, it should check error pointer instead of NULL.
2. It doesn't unregister interface if it fails to setup hsr interface.
If it fails to initialize hsr interface after register_netdevice(),
it should call unregister_netdevice().
3. Ignore failure of creation of debugfs
If creating of debugfs dir and file is failed, creating hsr interface
will be failed. But debugfs doesn't affect actual logic of hsr module.
So, ignoring this is more correct and this behavior is more general.
Fixes: c5a7591172 ("net/hsr: Use list_head (and rcu) instead of array for slave devices.")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Switching from ->priv_destructor to dellink() has an unexpected
consequence: existing RCU readers, that is, hsr_port_get_hsr()
callers, may still be able to read the port list.
Instead of checking the return value of each hsr_port_get_hsr(),
we can just move it to ->ndo_uninit() which is called after
device unregister and synchronize_net(), and we still have RTNL
lock there.
Fixes: b9a1e62740 ("hsr: implement dellink to clean up resources")
Fixes: edf070a0fb ("hsr: fix a NULL pointer deref in hsr_dev_xmit()")
Reported-by: syzbot+097ef84cdc95843fbaa8@syzkaller.appspotmail.com
Cc: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hsr_link_ops implements ->newlink() but not ->dellink(),
which leads that resources not released after removing the device,
particularly the entries in self_node_db and node_db.
So add ->dellink() implementation to replace the priv_destructor.
This also makes the code slightly easier to understand.
Reported-by: syzbot+c6167ec3de7def23d1e8@syzkaller.appspotmail.com
Cc: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hsr_del_port() should release all the resources allocated
in hsr_add_port().
As a consequence of this change, hsr_for_each_port() is no
longer safe to work with hsr_del_port(), switch to
list_for_each_entry_safe() as we always hold RTNL lock.
Cc: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't prune the master node in the hsr_prune_nodes function.
Neither time_in[HSR_PT_SLAVE_A] nor time_in[HSR_PT_SLAVE_B]
will ever be updated by hsr_register_frame_in for the master port.
Thus, the master node will be repeatedly pruned leading to
repeated packet loss.
This bug never appeared because the hsr_prune_nodes function
was only called once. Since commit 5150b45fd3
("net: hsr: Fix node prune function for forget time expiry") this issue
is fixed unveiling the issue described above.
Fixes: 5150b45fd3 ("net: hsr: Fix node prune function for forget time expiry")
Signed-off-by: Andreas Oetken <andreas.oetken@siemens.com>
Tested-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add options to strictly validate messages and dump messages,
sometimes perhaps validating dump messages non-strictly may
be required, so add an option for that as well.
Since none of this can really be applied to existing commands,
set the options everwhere using the following spatch:
@@
identifier ops;
expression X;
@@
struct genl_ops ops[] = {
...,
{
.cmd = X,
+ .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
...
},
...
};
For new commands one should just not copy the .validate 'opt-out'
flags and thus get strict validation.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add tx stats to hsr interface. Without this
ifconfig for hsr interface doesn't show tx packet stats.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix the path of hsr debugfs root directory to use the net device
name so that it can work with multiple interfaces. While at it,
also fix some typos.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix the file name and functions to match with existing implementation.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
HSR should forget nodes after configured node forget time expiry based
on HSR_NODE_FORGET_TIME. As part of hsr_prune_nodes(), code checks to
see if entries are to be flushed out if not heard for longer than forget
time. But currently hsr_prune_nodes() is called only once during device
creation. Restart the timer at the end of hsr_prune_nodes() so that
hsr_prune_nodes() gets called periodically and forgotten entries are
removed from node table.
Signed-off-by: Aaron Kramer <a-kramer@ti.com>
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds a debugfs interface to allow display the nodes learned
by the hsr master.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use SPDX-License-Identifier instead of a verbose license text.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a blank line after function declaration as suggested by
checkpatch.pl -f
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Current driver code uses camel case in many places. This is
seen when ran checkpatch.pl -f on files under net/hsr. This
patch fixes the code to remove camel case usage.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch add missing space around operator in code. This is
seen when ran checkpatch.pl -f on files under net/hsr.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In a multi-line statement exceeding 80 characters, logical operator
should be at the end of a line instead of being at the start. This
is seen when ran checkpatch.pl -f on files under net/hsr. The change
is per suggestion from checkpatch.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes unnecessary space after a cast. This is seen
when ran checkpatch.pl -f on files under net/hsr.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch replaces all instance of NULL checks such as
if (foo == NULL) with if (!foo)
Also
if (foo != NULL) with if (foo)
This is seen when ran checkpatch.pl -f on files under net/hsr
and suggestion is to replace as above.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes function calls that ends with '(' in a line.
This is seen when ran checkpatch.pl -f option on files under
net/hsr.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes alignment issues in code for functions. This is
seen when ran checkpatch.pl -f option on files under net/hsr.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes unnecessary paranthesis from the code. This is
seen when ran checkpatch.pl -f option on files under net/hsr.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes multiple blank lines in the code. This is seen
when ran checkpatch.pl -f option for files under net/hsr
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes lines exceeding 80 characters. This is seen
when ran checkpatch.pl with -f option for files under
net/hsr.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since maxattr is common, the policy can't really differ sanely,
so make it common as well.
The only user that did in fact manage to make a non-common policy
is taskstats, which has to be really careful about it (since it's
still using a common maxattr!). This is no longer supported, but
we can fake it using pre_doit.
This reduces the size of e.g. nl80211.o (which has lots of commands):
text data bss dec hex filename
398745 14323 2240 415308 6564c net/wireless/nl80211.o (before)
397913 14331 2240 414484 65314 net/wireless/nl80211.o (after)
--------------------------------
-832 +8 0 -824
Which is obviously just 8 bytes for each command, and an added 8
bytes for the new policy pointer. I'm not sure why the ops list is
counted as .text though.
Most of the code transformations were done using the following spatch:
@ops@
identifier OPS;
expression POLICY;
@@
struct genl_ops OPS[] = {
...,
{
- .policy = POLICY,
},
...
};
@@
identifier ops.OPS;
expression ops.POLICY;
identifier fam;
expression M;
@@
struct genl_family fam = {
.ops = OPS,
.maxattr = M,
+ .policy = POLICY,
...
};
This also gets rid of devlink_nl_cmd_region_read_dumpit() accessing
the cb->data as ops, which we want to change in a later genl patch.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.
Cc: Arvid Brodin <arvid.brodin@alten.se>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb_put_padto() will free the sk_buff passed as reference in case of
errors, but we still need to check its return value and decide what to
do.
Detected by CoverityScan, CID#1416688 ("CHECKED_RETURN")
Fixes: ee1c279772 ("net/hsr: Added support for HSR v1")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for extended error reporting.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When HSR interface is setup using ip link command, an annoying warning
appears with the trace as below:-
[ 203.019828] hsr_get_node: Non-HSR frame
[ 203.019833] Modules linked in:
[ 203.019848] CPU: 0 PID: 158 Comm: sd-resolve Tainted: G W 4.12.0-rc3-00052-g9fa6bf70 #2
[ 203.019853] Hardware name: Generic DRA74X (Flattened Device Tree)
[ 203.019869] [<c0110280>] (unwind_backtrace) from [<c010c2f4>] (show_stack+0x10/0x14)
[ 203.019880] [<c010c2f4>] (show_stack) from [<c04b9f64>] (dump_stack+0xac/0xe0)
[ 203.019894] [<c04b9f64>] (dump_stack) from [<c01374e8>] (__warn+0xd8/0x104)
[ 203.019907] [<c01374e8>] (__warn) from [<c0137548>] (warn_slowpath_fmt+0x34/0x44)
root@am57xx-evm:~# [ 203.019921] [<c0137548>] (warn_slowpath_fmt) from [<c081126c>] (hsr_get_node+0x148/0x170)
[ 203.019932] [<c081126c>] (hsr_get_node) from [<c0814240>] (hsr_forward_skb+0x110/0x7c0)
[ 203.019942] [<c0814240>] (hsr_forward_skb) from [<c0811d64>] (hsr_dev_xmit+0x2c/0x34)
[ 203.019954] [<c0811d64>] (hsr_dev_xmit) from [<c06c0828>] (dev_hard_start_xmit+0xc4/0x3bc)
[ 203.019963] [<c06c0828>] (dev_hard_start_xmit) from [<c06c13d8>] (__dev_queue_xmit+0x7c4/0x98c)
[ 203.019974] [<c06c13d8>] (__dev_queue_xmit) from [<c0782f54>] (ip6_finish_output2+0x330/0xc1c)
[ 203.019983] [<c0782f54>] (ip6_finish_output2) from [<c0788f0c>] (ip6_output+0x58/0x454)
[ 203.019994] [<c0788f0c>] (ip6_output) from [<c07b16cc>] (mld_sendpack+0x420/0x744)
As this is an expected path to hsr_get_node() with frame coming from
the master interface, add a check to ensure packet is not from the
master port and then warn.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Network devices can allocate reasources and private memory using
netdev_ops->ndo_init(). However, the release of these resources
can occur in one of two different places.
Either netdev_ops->ndo_uninit() or netdev->destructor().
The decision of which operation frees the resources depends upon
whether it is necessary for all netdev refs to be released before it
is safe to perform the freeing.
netdev_ops->ndo_uninit() presumably can occur right after the
NETDEV_UNREGISTER notifier completes and the unicast and multicast
address lists are flushed.
netdev->destructor(), on the other hand, does not run until the
netdev references all go away.
Further complicating the situation is that netdev->destructor()
almost universally does also a free_netdev().
This creates a problem for the logic in register_netdevice().
Because all callers of register_netdevice() manage the freeing
of the netdev, and invoke free_netdev(dev) if register_netdevice()
fails.
If netdev_ops->ndo_init() succeeds, but something else fails inside
of register_netdevice(), it does call ndo_ops->ndo_uninit(). But
it is not able to invoke netdev->destructor().
This is because netdev->destructor() will do a free_netdev() and
then the caller of register_netdevice() will do the same.
However, this means that the resources that would normally be released
by netdev->destructor() will not be.
Over the years drivers have added local hacks to deal with this, by
invoking their destructor parts by hand when register_netdevice()
fails.
Many drivers do not try to deal with this, and instead we have leaks.
Let's close this hole by formalizing the distinction between what
private things need to be freed up by netdev->destructor() and whether
the driver needs unregister_netdevice() to perform the free_netdev().
netdev->priv_destructor() performs all actions to free up the private
resources that used to be freed by netdev->destructor(), except for
free_netdev().
netdev->needs_free_netdev is a boolean that indicates whether
free_netdev() should be done at the end of unregister_netdevice().
Now, register_netdevice() can sanely release all resources after
ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit()
and netdev->priv_destructor().
And at the end of unregister_netdevice(), we invoke
netdev->priv_destructor() and optionally call free_netdev().
Signed-off-by: David S. Miller <davem@davemloft.net>
Taehee Yoo