6.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet <edumazet@xxxxxxxxxx>
[ Upstream commit 979b581e4c69257acab1af415ddad6b2d78a2fa5 ]
I have seen the WARN_ON(smp_processor_id() != cpu) firing
in pktgen_thread_worker() during tests.
We must use cpus_read_lock()/cpus_read_unlock()
around the for_each_online_cpu(cpu) loop.
While we are at it use WARN_ON_ONCE() to avoid a possible syslog flood.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Link: https://patch.msgid.link/20240821175339.1191779-1-edumazet@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/core/pktgen.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index ea55a758a475a..197a50ef8e2e1 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -3654,7 +3654,7 @@ static int pktgen_thread_worker(void *arg)
struct pktgen_dev *pkt_dev = NULL;
int cpu = t->cpu;
- WARN_ON(smp_processor_id() != cpu);
+ WARN_ON_ONCE(smp_processor_id() != cpu);
init_waitqueue_head(&t->queue);
complete(&t->start_done);
@@ -3989,6 +3989,7 @@ static int __net_init pg_net_init(struct net *net)
goto remove;
}
+ cpus_read_lock();
for_each_online_cpu(cpu) {
int err;
@@ -3997,6 +3998,7 @@ static int __net_init pg_net_init(struct net *net)
pr_warn("Cannot create thread for cpu %d (%d)\n",
cpu, err);
}
+ cpus_read_unlock();
if (list_empty(&pn->pktgen_threads)) {
pr_err("Initialization failed for all threads\n");
--
2.43.0
