From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E7F3A36F8E8 for ; Thu, 28 May 2026 23:16:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780010216; cv=none; b=hHafXMiXNMPyBBxP1GuGFIRIvJz7QAX1olAq17aAp2rOSTZPomBWftZpvdjaTMiCfB5v8lwcieothphlFVRho6c2/pmYkH77ijWG4BnR4Yc9SU3s5KuQCCnURidvVMNe2NOVIWdZXNGnSYYOwhvHI8D6na0WhLnpzqeyxMWjNOA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780010216; c=relaxed/simple; bh=I0ZNqX2NkV+XI+klKtTvtW1xDwmIEZrTRpYIaSStszE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Fsc0wMI6Z99nrq+7azOfugbYwyfh4DKlTWwy/DNaMzoaz8h7fW8rgLlBG/eByKkkhl32R6BAOV24TElaheGPASE9Oz0U/H+xQ42CYdsX/eSfr6TYHXA2w5pIQBKlFh1KDSaluOguRctvSu2zcRX6L06toyKWuHyO20zV69LlYdE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HpZJdz7N; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="HpZJdz7N" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 105B01F00A3C; Thu, 28 May 2026 23:16:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780010214; bh=lJVou6mnvTd1LGzW+G2hvFIMtaLbMT9thPt3UqaG1u4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=HpZJdz7NomfBoXNmM7ETuZP3OI4YX78v2jYak8YUxGKPoSOdwiaWyoQv0cN1CsMtW S/eGbstzN6OTR5i4g4wVrrpKcFApr7U2uJ0hzbdjgzRMHsmfLYAhM8fE2JMbe8KaHJ xcJ53ZpNjyoDTczC7ca4vEidjsq8GxTnyLr4A3ijG+Asquk9A2N/2KOKl2KHFi3Y3L QvyWouBI5Yoz/oOoNECAAV3sDMZda1bTsSB2z/jSasxz6Pxcg6qVWcrn8EykGdqe1h mgx5nCu+43iavpJLde3aibjX+Q6uBXdrO1A8W42EM7GctdS4Gjt7B7W52nIR99Irbx qTH0j8Gok8wLA== From: Jakub Kicinski To: davem@davemloft.net Cc: netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com, andrew+netdev@lunn.ch, horms@kernel.org, michael.chan@broadcom.com, joshwash@google.com, tariqt@nvidia.com, haiyangz@microsoft.com, linux@armlinux.org.uk, maxime.chevallier@bootlin.com, willemb@google.com, ernis@linux.microsoft.com, sdf.kernel@gmail.com, kory.maincent@bootlin.com, danieller@nvidia.com, idosch@nvidia.com, Jakub Kicinski Subject: [PATCH net-next 07/14] net: ethtool: optionally skip rtnl_lock on Netlink path for SET ops Date: Thu, 28 May 2026 16:16:30 -0700 Message-ID: <20260528231637.251822-8-kuba@kernel.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260528231637.251822-1-kuba@kernel.org> References: <20260528231637.251822-1-kuba@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Make ethtool not take rtnl_lock for SET commands when operation is performed on an ops-locked driver. cfg/cfg_pending are now ops-locked, since only ethtool modifies them. Some SET driver callbacks will still need rtnl_lock, most notably those which may end up calling netdev_update_features() or the qdisc layer (via netif_set_real_num_tx_queues()). Let drivers selectively opt back into the rtnl_lock with a new bitfield in ops. We need two helpers since Netlink and ioctl cmds have different values. Keep the helpers side by side in common.h to make sure they get updated together, even tho they will only get called from ioctl.c and netlink.c. SET commands which don't use ethnl_default_set_doit() are converted by subsequent commits. Signed-off-by: Jakub Kicinski --- include/linux/ethtool.h | 8 +++++ include/linux/netdevice.h | 2 +- net/ethtool/common.h | 30 +++++++++++++++++++ .../net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 4 +++ drivers/net/ethernet/google/gve/gve_ethtool.c | 2 ++ .../ethernet/mellanox/mlx5/core/en_ethtool.c | 3 ++ .../net/ethernet/mellanox/mlx5/core/en_rep.c | 2 ++ .../mellanox/mlx5/core/ipoib/ethtool.c | 2 ++ .../net/ethernet/meta/fbnic/fbnic_ethtool.c | 5 +++- .../ethernet/microsoft/mana/mana_ethtool.c | 2 ++ drivers/net/netdevsim/ethtool.c | 1 + net/ethtool/netlink.c | 9 ++++-- 12 files changed, 66 insertions(+), 4 deletions(-) diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h index f4f933b8be26..4f15221119e2 100644 --- a/include/linux/ethtool.h +++ b/include/linux/ethtool.h @@ -936,6 +936,12 @@ struct kernel_ethtool_ts_info { */ #define ETHTOOL_OP_NEEDS_RTNL_LINKSETTINGS BIT(0) #define ETHTOOL_OP_NEEDS_RTNL_GPAUSEPARAM BIT(1) +#define ETHTOOL_OP_NEEDS_RTNL_SPFLAGS BIT(2) +#define ETHTOOL_OP_NEEDS_RTNL_SRINGPARAM BIT(3) +#define ETHTOOL_OP_NEEDS_RTNL_SCHANNELS BIT(4) +#define ETHTOOL_OP_NEEDS_RTNL_SCOALESCE BIT(5) +#define ETHTOOL_OP_NEEDS_RTNL_SPAUSEPARAM BIT(6) +#define ETHTOOL_OP_NEEDS_RTNL_RSS BIT(7) /** * struct ethtool_ops - optional netdev operations @@ -970,6 +976,8 @@ struct kernel_ethtool_ts_info { * The following commonly used core APIs currently require rtnl_lock * (this list may not be exhaustive): * - phylink helpers (note that phydev is currently unsupported!) + * - netdev_update_features() + * - netif_set_real_num_tx_queues() * * @get_drvinfo: Report driver/device information. Modern drivers no * longer have to implement this callback. Most fields are diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 2d9a658e9b1a..08db7305e0f9 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2585,7 +2585,7 @@ struct net_device { * @up, @moving_ns, @nd_net, @xdp_features * * Ops protects: - * @hwprov + * @cfg, @cfg_pending, @hwprov * * Double ops protects: * @real_num_rx_queues, @real_num_tx_queues diff --git a/net/ethtool/common.h b/net/ethtool/common.h index 391c41ca56be..e3052972f953 100644 --- a/net/ethtool/common.h +++ b/net/ethtool/common.h @@ -95,10 +95,24 @@ ethtool_nl_msg_needs_rtnl(const struct net_device *dev, u8 cmd) switch (cmd) { case ETHTOOL_MSG_LINKINFO_GET: + case ETHTOOL_MSG_LINKINFO_SET: case ETHTOOL_MSG_LINKMODES_GET: + case ETHTOOL_MSG_LINKMODES_SET: return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_LINKSETTINGS; + case ETHTOOL_MSG_PRIVFLAGS_SET: + return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_SPFLAGS; + case ETHTOOL_MSG_RINGS_SET: + return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_SRINGPARAM; + case ETHTOOL_MSG_CHANNELS_SET: + return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_SCHANNELS; + case ETHTOOL_MSG_COALESCE_SET: + return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_SCOALESCE; case ETHTOOL_MSG_PAUSE_GET: return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_GPAUSEPARAM; + case ETHTOOL_MSG_PAUSE_SET: + return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_SPAUSEPARAM; + case ETHTOOL_MSG_RSS_SET: + return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_RSS; } return false; } @@ -119,9 +133,25 @@ ethtool_ioctl_needs_rtnl(const struct net_device *dev, u32 ethcmd) switch (ethcmd) { case ETHTOOL_GLINKSETTINGS: case ETHTOOL_GSET: + case ETHTOOL_SLINKSETTINGS: + case ETHTOOL_SSET: return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_LINKSETTINGS; + case ETHTOOL_SPFLAGS: + return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_SPFLAGS; + case ETHTOOL_SRINGPARAM: + return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_SRINGPARAM; + case ETHTOOL_SCHANNELS: + return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_SCHANNELS; + case ETHTOOL_SCOALESCE: + return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_SCOALESCE; case ETHTOOL_GPAUSEPARAM: return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_GPAUSEPARAM; + case ETHTOOL_SPAUSEPARAM: + return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_SPAUSEPARAM; + case ETHTOOL_SRSSH: + case ETHTOOL_SRXFH: + case ETHTOOL_SRXFHINDIR: + return ops->op_needs_rtnl & ETHTOOL_OP_NEEDS_RTNL_RSS; } return false; } diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c index 9b14134d62d2..c8a87ed9283e 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c @@ -5729,6 +5729,10 @@ const struct ethtool_ops bnxt_ethtool_ops = { .rxfh_max_num_contexts = BNXT_MAX_ETH_RSS_CTX + 1, .rxfh_indir_space = BNXT_MAX_RSS_TABLE_ENTRIES_P5, .rxfh_priv_size = sizeof(struct bnxt_rss_ctx), + .op_needs_rtnl = ETHTOOL_OP_NEEDS_RTNL_SCHANNELS | + ETHTOOL_OP_NEEDS_RTNL_SRINGPARAM | + ETHTOOL_OP_NEEDS_RTNL_SCOALESCE | + ETHTOOL_OP_NEEDS_RTNL_RSS, .supported_coalesce_params = ETHTOOL_COALESCE_USECS | ETHTOOL_COALESCE_MAX_FRAMES | ETHTOOL_COALESCE_USECS_IRQ | diff --git a/drivers/net/ethernet/google/gve/gve_ethtool.c b/drivers/net/ethernet/google/gve/gve_ethtool.c index dc2213b5ce24..f4b2b14237ba 100644 --- a/drivers/net/ethernet/google/gve/gve_ethtool.c +++ b/drivers/net/ethernet/google/gve/gve_ethtool.c @@ -983,6 +983,8 @@ const struct ethtool_ops gve_ethtool_ops = { .supported_coalesce_params = ETHTOOL_COALESCE_USECS, .supported_ring_params = ETHTOOL_RING_USE_TCP_DATA_SPLIT | ETHTOOL_RING_USE_RX_BUF_LEN, + .op_needs_rtnl = ETHTOOL_OP_NEEDS_RTNL_SCHANNELS | + ETHTOOL_OP_NEEDS_RTNL_SRINGPARAM, .get_drvinfo = gve_get_drvinfo, .get_strings = gve_get_strings, .get_sset_count = gve_get_sset_count, diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c index 61993485e451..2f5b626ba33f 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c @@ -2719,6 +2719,9 @@ const struct ethtool_ops mlx5e_ethtool_ops = { .rxfh_per_ctx_fields = true, .rxfh_per_ctx_key = true, .rxfh_max_num_contexts = MLX5E_MAX_NUM_RSS, + .op_needs_rtnl = ETHTOOL_OP_NEEDS_RTNL_SCHANNELS | + ETHTOOL_OP_NEEDS_RTNL_SRINGPARAM | + ETHTOOL_OP_NEEDS_RTNL_SPFLAGS, .supported_coalesce_params = ETHTOOL_COALESCE_USECS | ETHTOOL_COALESCE_MAX_FRAMES | ETHTOOL_COALESCE_USE_ADAPTIVE | diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c index ba6c0f38cc73..1a8a19f980d3 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c @@ -418,6 +418,8 @@ static const struct ethtool_ops mlx5e_rep_ethtool_ops = { .supported_coalesce_params = ETHTOOL_COALESCE_USECS | ETHTOOL_COALESCE_MAX_FRAMES | ETHTOOL_COALESCE_USE_ADAPTIVE, + .op_needs_rtnl = ETHTOOL_OP_NEEDS_RTNL_SCHANNELS | + ETHTOOL_OP_NEEDS_RTNL_SRINGPARAM, .get_drvinfo = mlx5e_rep_get_drvinfo, .get_link = ethtool_op_get_link, .get_strings = mlx5e_rep_get_strings, diff --git a/drivers/net/ethernet/mellanox/mlx5/core/ipoib/ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/ipoib/ethtool.c index 3b2f54ca30a8..9b3b32408c64 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/ipoib/ethtool.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/ipoib/ethtool.c @@ -285,6 +285,8 @@ const struct ethtool_ops mlx5i_ethtool_ops = { .supported_coalesce_params = ETHTOOL_COALESCE_USECS | ETHTOOL_COALESCE_MAX_FRAMES | ETHTOOL_COALESCE_USE_ADAPTIVE, + .op_needs_rtnl = ETHTOOL_OP_NEEDS_RTNL_SCHANNELS | + ETHTOOL_OP_NEEDS_RTNL_SRINGPARAM, .get_drvinfo = mlx5i_get_drvinfo, .get_strings = mlx5i_get_strings, .get_sset_count = mlx5i_get_sset_count, diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c b/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c index a2c16d599389..2e5a4a0ff972 100644 --- a/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c +++ b/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c @@ -2021,7 +2021,10 @@ static const struct ethtool_ops fbnic_ethtool_ops = { ETHTOOL_RING_USE_HDS_THRS, .rxfh_max_num_contexts = FBNIC_RPC_RSS_TBL_COUNT, .op_needs_rtnl = ETHTOOL_OP_NEEDS_RTNL_LINKSETTINGS | - ETHTOOL_OP_NEEDS_RTNL_GPAUSEPARAM, + ETHTOOL_OP_NEEDS_RTNL_GPAUSEPARAM | + ETHTOOL_OP_NEEDS_RTNL_SCHANNELS | + ETHTOOL_OP_NEEDS_RTNL_SRINGPARAM | + ETHTOOL_OP_NEEDS_RTNL_SPAUSEPARAM, .get_drvinfo = fbnic_get_drvinfo, .get_regs_len = fbnic_get_regs_len, .get_regs = fbnic_get_regs, diff --git a/drivers/net/ethernet/microsoft/mana/mana_ethtool.c b/drivers/net/ethernet/microsoft/mana/mana_ethtool.c index 04350973e19e..55df44d728a0 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_ethtool.c +++ b/drivers/net/ethernet/microsoft/mana/mana_ethtool.c @@ -575,6 +575,8 @@ static int mana_get_link_ksettings(struct net_device *ndev, const struct ethtool_ops mana_ethtool_ops = { .supported_coalesce_params = ETHTOOL_COALESCE_RX_CQE_FRAMES, + .op_needs_rtnl = ETHTOOL_OP_NEEDS_RTNL_SCHANNELS | + ETHTOOL_OP_NEEDS_RTNL_SRINGPARAM, .get_ethtool_stats = mana_get_ethtool_stats, .get_sset_count = mana_get_sset_count, .get_strings = mana_get_strings, diff --git a/drivers/net/netdevsim/ethtool.c b/drivers/net/netdevsim/ethtool.c index 36a201533aae..9350ba48eb81 100644 --- a/drivers/net/netdevsim/ethtool.c +++ b/drivers/net/netdevsim/ethtool.c @@ -209,6 +209,7 @@ static const struct ethtool_ops nsim_ethtool_ops = { .supported_coalesce_params = ETHTOOL_COALESCE_ALL_PARAMS, .supported_ring_params = ETHTOOL_RING_USE_TCP_DATA_SPLIT | ETHTOOL_RING_USE_HDS_THRS, + .op_needs_rtnl = ETHTOOL_OP_NEEDS_RTNL_SCHANNELS, .get_pause_stats = nsim_get_pause_stats, .get_pauseparam = nsim_get_pauseparam, .set_pauseparam = nsim_set_pauseparam, diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c index ddb35790063d..16f6d7f81502 100644 --- a/net/ethtool/netlink.c +++ b/net/ethtool/netlink.c @@ -903,6 +903,7 @@ static int ethnl_default_set_doit(struct sk_buff *skb, struct genl_info *info) const u8 cmd = info->genlhdr->cmd; struct ethnl_req_info *req_info; struct net_device *dev; + bool need_rtnl; int ret; ops = ethnl_default_requests[cmd]; @@ -927,8 +928,11 @@ static int ethnl_default_set_doit(struct sk_buff *skb, struct genl_info *info) } dev = req_info->dev; + need_rtnl = !netdev_need_ops_lock(dev) || + ethtool_nl_msg_needs_rtnl(dev, cmd); - rtnl_lock(); + if (need_rtnl) + rtnl_lock(); netdev_lock_ops(dev); dev->cfg_pending = kmemdup(dev->cfg, sizeof(*dev->cfg), GFP_KERNEL_ACCOUNT); @@ -958,7 +962,8 @@ static int ethnl_default_set_doit(struct sk_buff *skb, struct genl_info *info) out_tie_cfg: dev->cfg_pending = dev->cfg; netdev_unlock_ops(dev); - rtnl_unlock(); + if (need_rtnl) + rtnl_unlock(); out_dev: ethnl_parse_header_dev_put(req_info); out_free_req: -- 2.54.0