diff options
| author | Jakub Kicinski <kuba@kernel.org> | 2026-06-24 12:04:39 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-06-25 10:18:34 -0700 |
| commit | 1105ef941c1a28e115d1b97f17e1c85576884100 (patch) | |
| tree | 26c90777896f27ffbc392a1f72aef8e574370a05 /include/linux | |
| parent | 2c0f1b651d8730c74a4b0cc325ec25808ec92e44 (diff) | |
net: ethtool: keep rtnl_lock for ops using ethtool_op_get_link()
Breno reports following splats on mlx5:
RTNL: assertion failed at net/core/dev.c (2241)
WARNING: net/core/dev.c:2241 at netif_state_change+0xed/0x130, CPU#5: ethtool/1335
RIP: 0010:netif_state_change+0xf9/0x130
Call Trace:
<TASK>
__linkwatch_sync_dev+0xea/0x120
ethtool_op_get_link+0xe/0x20
__ethtool_get_link+0x26/0x40
linkstate_prepare_data+0x51/0x200
ethnl_default_doit+0x213/0x470
genl_family_rcv_msg_doit+0xdd/0x110
Looks like I missed ethtool_op_get_link() trying to sync linkwatch,
which needs rtnl_lock. Not all drivers do this - bnxt doesn't,
it just returns the link state, so add an opt-in bit.
Reported-by: Breno Leitao <leitao@debian.org>
Fixes: 45079e00133e ("net: ethtool: optionally skip rtnl_lock on Netlink path for GET ops")
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Breno Leitao <leitao@debian.org>
Acked-by: Harshitha Ramamurthy <hramamurthy@google.com>
Link: https://patch.msgid.link/20260624190439.2521219-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/ethtool.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h index 1b834e2a522e..5d491a98265e 100644 --- a/include/linux/ethtool.h +++ b/include/linux/ethtool.h @@ -942,6 +942,7 @@ struct kernel_ethtool_ts_info { #define ETHTOOL_OP_NEEDS_RTNL_GPAUSEPARAM BIT(5) #define ETHTOOL_OP_NEEDS_RTNL_SPAUSEPARAM BIT(6) #define ETHTOOL_OP_NEEDS_RTNL_RSS BIT(7) +#define ETHTOOL_OP_NEEDS_RTNL_GLINK BIT(8) /** * struct ethtool_ops - optional netdev operations @@ -978,6 +979,7 @@ struct kernel_ethtool_ts_info { * - phylink helpers (note that phydev is currently unsupported!) * - netdev_update_features() * - netif_set_real_num_tx_queues() + * - ethtool_op_get_link() (syncs link watch under rtnl_lock) * * @get_drvinfo: Report driver/device information. Modern drivers no * longer have to implement this callback. Most fields are |