From facd15dfd69122042502d99ab8c9f888b48ee994 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Mon, 4 Dec 2023 21:47:07 +0100 Subject: net: core: synchronize link-watch when carrier is queried There are multiple ways to query for the carrier state: through rtnetlink, sysfs, and (possibly) ethtool. Synchronize linkwatch work before these operations so that we don't have a situation where userspace queries the carrier state between the driver's carrier off->on transition and linkwatch running and expects it to work, when really (at least) TX cannot work until linkwatch has run. I previously posted a longer explanation of how this applies to wireless [1] but with this wireless can simply query the state before sending data, to ensure the kernel is ready for it. [1] https://lore.kernel.org/all/346b21d87c69f817ea3c37caceb34f1f56255884.camel@sipsolutions.net/ Signed-off-by: Johannes Berg Reviewed-by: Jiri Pirko Link: https://lore.kernel.org/r/20231204214706.303c62768415.I1caedccae72ee5a45c9085c5eb49c145ce1c0dd5@changeid Signed-off-by: Jakub Kicinski --- net/core/dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/core/dev.c') diff --git a/net/core/dev.c b/net/core/dev.c index c5679dfbaa70..0432b04cf9b0 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -10548,7 +10548,7 @@ void netdev_run_todo(void) write_lock(&dev_base_lock); dev->reg_state = NETREG_UNREGISTERED; write_unlock(&dev_base_lock); - linkwatch_forget_dev(dev); + linkwatch_sync_dev(dev); } while (!list_empty(&list)) { -- cgit v1.2.3