diff options
Diffstat (limited to 'target/linux/generic/backport-5.4/604-v5.12-net-fix-hangup-on-napi_disable-for-threaded-napi.patch')
-rw-r--r-- | target/linux/generic/backport-5.4/604-v5.12-net-fix-hangup-on-napi_disable-for-threaded-napi.patch | 53 |
1 files changed, 0 insertions, 53 deletions
diff --git a/target/linux/generic/backport-5.4/604-v5.12-net-fix-hangup-on-napi_disable-for-threaded-napi.patch b/target/linux/generic/backport-5.4/604-v5.12-net-fix-hangup-on-napi_disable-for-threaded-napi.patch deleted file mode 100644 index 5c48fdf5c1..0000000000 --- a/target/linux/generic/backport-5.4/604-v5.12-net-fix-hangup-on-napi_disable-for-threaded-napi.patch +++ /dev/null @@ -1,53 +0,0 @@ -From: Paolo Abeni <pabeni@redhat.com> -Date: Fri, 9 Apr 2021 17:24:17 +0200 -Subject: [PATCH] net: fix hangup on napi_disable for threaded napi - -napi_disable() is subject to an hangup, when the threaded -mode is enabled and the napi is under heavy traffic. - -If the relevant napi has been scheduled and the napi_disable() -kicks in before the next napi_threaded_wait() completes - so -that the latter quits due to the napi_disable_pending() condition, -the existing code leaves the NAPI_STATE_SCHED bit set and the -napi_disable() loop waiting for such bit will hang. - -This patch addresses the issue by dropping the NAPI_STATE_DISABLE -bit test in napi_thread_wait(). The later napi_threaded_poll() -iteration will take care of clearing the NAPI_STATE_SCHED. - -This also addresses a related problem reported by Jakub: -before this patch a napi_disable()/napi_enable() pair killed -the napi thread, effectively disabling the threaded mode. -On the patched kernel napi_disable() simply stops scheduling -the relevant thread. - -v1 -> v2: - - let the main napi_thread_poll() loop clear the SCHED bit - -Reported-by: Jakub Kicinski <kuba@kernel.org> -Fixes: 29863d41bb6e ("net: implement threaded-able napi poll loop support") -Signed-off-by: Paolo Abeni <pabeni@redhat.com> -Reviewed-by: Eric Dumazet <edumazet@google.com> -Link: https://lore.kernel.org/r/883923fa22745a9589e8610962b7dc59df09fb1f.1617981844.git.pabeni@redhat.com -Signed-off-by: Jakub Kicinski <kuba@kernel.org> ---- - ---- a/net/core/dev.c -+++ b/net/core/dev.c -@@ -6521,7 +6521,7 @@ static int napi_thread_wait(struct napi_ - - set_current_state(TASK_INTERRUPTIBLE); - -- while (!kthread_should_stop() && !napi_disable_pending(napi)) { -+ while (!kthread_should_stop()) { - /* Testing SCHED_THREADED bit here to make sure the current - * kthread owns this napi and could poll on this napi. - * Testing SCHED bit is not enough because SCHED bit might be -@@ -6539,6 +6539,7 @@ static int napi_thread_wait(struct napi_ - set_current_state(TASK_INTERRUPTIBLE); - } - __set_current_state(TASK_RUNNING); -+ - return -1; - } - |