| Message ID | 20240821175339.1191779-1-edumazet@google.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 979b581e4c69257acab1af415ddad6b2d78a2fa5 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] pktgen: use cpus_read_lock() in pg_net_init() | expand |
Hello: This patch was applied to netdev/net.git (main) by Jakub Kicinski <kuba@kernel.org>: On Wed, 21 Aug 2024 17:53:39 +0000 you wrote: > 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. > > [...] Here is the summary with links: - [net] pktgen: use cpus_read_lock() in pg_net_init() https://git.kernel.org/netdev/net/c/979b581e4c69 You are awesome, thank you!
diff --git a/net/core/pktgen.c b/net/core/pktgen.c index ea55a758a475ab0ee22d9ac91f0ac9f0a6975e1f..197a50ef8e2e1bbe9f3906dfb80e80d913534b81 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");
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> --- net/core/pktgen.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)