Revision c269a24ce057abfc31130960e96ab197ef6ab196 authored by Jakub Kicinski on 06 January 2021, 18:40:06 UTC, committed by Jakub Kicinski on 09 January 2021, 03:27:41 UTC
There are two flavors of handling netdev registration: - ones called without holding rtnl_lock: register_netdev() and unregister_netdev(); and - those called with rtnl_lock held: register_netdevice() and unregister_netdevice(). While the semantics of the former are pretty clear, the same can't be said about the latter. The netdev_todo mechanism is utilized to perform some of the device unregistering tasks and it hooks into rtnl_unlock() so the locked variants can't actually finish the work. In general free_netdev() does not mix well with locked calls. Most drivers operating under rtnl_lock set dev->needs_free_netdev to true and expect core to make the free_netdev() call some time later. The part where this becomes most problematic is error paths. There is no way to unwind the state cleanly after a call to register_netdevice(), since unreg can't be performed fully without dropping locks. Make free_netdev() more lenient, and defer the freeing if device is being unregistered. This allows error paths to simply call free_netdev() both after register_netdevice() failed, and after a call to unregister_netdevice() but before dropping rtnl_lock. Simplify the error paths which are currently doing gymnastics around free_netdev() handling. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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File | Mode | Size |
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Makefile | -rw-r--r-- | 394 bytes |
decode-fcp.c | -rw-r--r-- | 5.5 KB |
list.h | -rw-r--r-- | 1.3 KB |
nosy-dump.c | -rw-r--r-- | 24.5 KB |
nosy-dump.h | -rw-r--r-- | 3.2 KB |
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