diff options
| author |   Vladimir Oltean <vladimir.oltean@nxp.com> | 2022-01-06 00:11:50 +0200 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2022-01-06 12:16:21 +0000 |
| commit | 1b26d364e4e9bd6540a8e7bcaf50e7f35041feb5 (patch) | |
| tree | 2139f98e543630040123b74a001db02449d3cfc6 /include/net | |
| parent | net: dsa: don't enumerate dsa_switch and dsa_port bit fields using commas (diff) | |
| download | linux-dev-1b26d364e4e9bd6540a8e7bcaf50e7f35041feb5.tar.xz linux-dev-1b26d364e4e9bd6540a8e7bcaf50e7f35041feb5.zip | |
net: dsa: warn about dsa_port and dsa_switch bit fields being non atomic
As discussed during review here:
https://patchwork.kernel.org/project/netdevbpf/patch/20220105132141.2648876-3-vladimir.oltean@nxp.com/
we should inform developers about pitfalls of concurrent access to the
boolean properties of dsa_switch and dsa_port, now that they've been
converted to bit fields. No other measure than a comment needs to be
taken, since the code paths that update these bit fields are not
concurrent with each other.
Suggested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net')
| -rw-r--r-- | include/net/dsa.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/net/dsa.h b/include/net/dsa.h index 63c7f553f938..57b3e4e7413b 100644 --- a/include/net/dsa.h +++ b/include/net/dsa.h @@ -265,6 +265,10 @@ struct dsa_port { u8 stp_state; + /* Warning: the following bit fields are not atomic, and updating them + * can only be done from code paths where concurrency is not possible + * (probe time or under rtnl_lock). + */ u8 vlan_filtering:1; /* Managed by DSA on user ports and by drivers on CPU and DSA ports */ @@ -333,6 +337,10 @@ struct dsa_switch { struct dsa_switch_tree *dst; unsigned int index; + /* Warning: the following bit fields are not atomic, and updating them + * can only be done from code paths where concurrency is not possible + * (probe time or under rtnl_lock). + */ u32 setup:1; /* Disallow bridge core from requesting different VLAN awareness |