nfp: Remove rcu_read_lock() around XDP program invocation

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The nfp driver has rcu_read_lock()/rcu_read_unlock() pairs around XDP
program invocations. However, the actual lifetime of the objects referred
by the XDP program invocation is longer, all the way through to the call to
xdp_do_flush(), making the scope of the rcu_read_lock() too small.

While this is not actually an issue for the nfp driver because it doesn't
support XDP_REDIRECT (and thus doesn't call xdp_do_flush()), the
rcu_read_lock() is still unneeded. And With the addition of RCU annotations
to the XDP_REDIRECT map types that take bh execution into account, lockdep
even understands this to be safe, so there's really no reason to keep it
around.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Cc: oss-drivers@netronome.com
Link: https://lore.kernel.org/bpf/20210624160609.292325-15-toke@redhat.com

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Toke Høiland-Jørgensen 2021-06-24 18:06:04 +02:00 • committed by Daniel Borkmann

parent c4411b371c

commit d5789621b6

1 changed files with 0 additions and 2 deletions

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drivers/net/ethernet/netronome/nfp/nfp_net_common.c

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