[PATCH net-next 10/11] net: protect NAPI config fields with netdev_lock()
From: Jakub Kicinski <kuba@kernel.org>
Date: 2025-01-14 03:51:37
Subsystem:
networking drivers, networking [general], the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Protect the following members of netdev and napi by netdev_lock: - defer_hard_irqs, - gro_flush_timeout, - irq_suspend_timeout. The first two are written via sysfs (which this patch switches to new lock), and netdev genl which holds both netdev and rtnl locks. irq_suspend_timeout is only written by netdev genl. Signed-off-by: Jakub Kicinski <kuba@kernel.org> --- include/linux/netdevice.h | 7 ++++--- net/core/net-sysfs.c | 5 +++-- 2 files changed, 7 insertions(+), 5 deletions(-)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 03eeeac7dbdf..e16c32be0681 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h@@ -384,11 +384,11 @@ struct napi_struct { int rx_count; /* length of rx_list */ unsigned int napi_id; /* protected by netdev_lock */ struct hrtimer timer; - struct task_struct *thread; /* protected by netdev_lock */ + /* all fields past this point are write-protected by netdev_lock */ + struct task_struct *thread; unsigned long gro_flush_timeout; unsigned long irq_suspend_timeout; u32 defer_hard_irqs; - /* all fields past this point are write-protected by netdev_lock */ /* control-path-only fields follow */ struct list_head dev_list; struct hlist_node napi_hash_node;
@@ -2452,7 +2452,8 @@ struct net_device { * Drivers are free to use it for other protection. * * Protects: - * @napi_list, @net_shaper_hierarchy, @reg_state, @threaded + * @gro_flush_timeout, @napi_defer_hard_irqs, @napi_list, + * @net_shaper_hierarchy, @reg_state, @threaded * Partially protects (readers hold either @lock or rtnl_lock, * writers must hold both for registered devices): * @up
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 5602a3c12e9a..173688663464 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c@@ -450,7 +450,7 @@ static ssize_t gro_flush_timeout_store(struct device *dev, if (!capable(CAP_NET_ADMIN)) return -EPERM; - return netdev_store(dev, attr, buf, len, change_gro_flush_timeout); + return netdev_lock_store(dev, attr, buf, len, change_gro_flush_timeout); } NETDEVICE_SHOW_RW(gro_flush_timeout, fmt_ulong);
@@ -470,7 +470,8 @@ static ssize_t napi_defer_hard_irqs_store(struct device *dev, if (!capable(CAP_NET_ADMIN)) return -EPERM; - return netdev_store(dev, attr, buf, len, change_napi_defer_hard_irqs); + return netdev_lock_store(dev, attr, buf, len, + change_napi_defer_hard_irqs); } NETDEVICE_SHOW_RW(napi_defer_hard_irqs, fmt_uint);
--
2.47.1