6.10-stable review patch. If anyone has any objections, please let me know.
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From: Eric Dumazet edumazet@google.com
[ 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@google.com Link: https://patch.msgid.link/20240821175339.1191779-1-edumazet@google.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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");