| Message ID | 20241122071630.63707-2-guwen@linux.alibaba.com (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | two fixes for SMC | expand |
On 22.11.24 08:16, Wen Gu wrote: > We encountered a warning that close_work was canceled before > initialization. > > WARNING: CPU: 7 PID: 111103 at kernel/workqueue.c:3047 __flush_work+0x19e/0x1b0 > Workqueue: events smc_lgr_terminate_work [smc] > RIP: 0010:__flush_work+0x19e/0x1b0 > Call Trace: > ? __wake_up_common+0x7a/0x190 > ? work_busy+0x80/0x80 > __cancel_work_timer+0xe3/0x160 > smc_close_cancel_work+0x1a/0x70 [smc] > smc_close_active_abort+0x207/0x360 [smc] > __smc_lgr_terminate.part.38+0xc8/0x180 [smc] > process_one_work+0x19e/0x340 > worker_thread+0x30/0x370 > ? process_one_work+0x340/0x340 > kthread+0x117/0x130 > ? __kthread_cancel_work+0x50/0x50 > ret_from_fork+0x22/0x30 > > This is because when smc_close_cancel_work is triggered, e.g. the RDMA > driver is rmmod and the LGR is terminated, the conn->close_work is > flushed before initialization, resulting in WARN_ON(!work->func). > > __smc_lgr_terminate | smc_connect_{rdma|ism} > ------------------------------------------------------------- > | smc_conn_create > | \- smc_lgr_register_conn > for conn in lgr->conns_all | > \- smc_conn_kill | > \- smc_close_active_abort | > \- smc_close_cancel_work | > \- cancel_work_sync | > \- __flush_work | > (close_work) | > | smc_close_init > | \- INIT_WORK(&close_work) > > So fix this by initializing close_work before establishing the > connection. > > Fixes: 46c28dbd4c23 ("net/smc: no socket state changes in tasklet context") > Fixes: 413498440e30 ("net/smc: add SMC-D support in af_smc") > Signed-off-by: Wen Gu <guwen@linux.alibaba.com> > --- It looks plausible to me. Thank you for fixing it! Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com> Thanks, Wenjia
On 22.11.24 08:16, Wen Gu wrote: > We encountered a warning that close_work was canceled before > initialization. > > WARNING: CPU: 7 PID: 111103 at kernel/workqueue.c:3047 __flush_work+0x19e/0x1b0 > Workqueue: events smc_lgr_terminate_work [smc] > RIP: 0010:__flush_work+0x19e/0x1b0 > Call Trace: > ? __wake_up_common+0x7a/0x190 > ? work_busy+0x80/0x80 > __cancel_work_timer+0xe3/0x160 > smc_close_cancel_work+0x1a/0x70 [smc] > smc_close_active_abort+0x207/0x360 [smc] > __smc_lgr_terminate.part.38+0xc8/0x180 [smc] > process_one_work+0x19e/0x340 > worker_thread+0x30/0x370 > ? process_one_work+0x340/0x340 > kthread+0x117/0x130 > ? __kthread_cancel_work+0x50/0x50 > ret_from_fork+0x22/0x30 > > This is because when smc_close_cancel_work is triggered, e.g. the RDMA > driver is rmmod and the LGR is terminated, the conn->close_work is > flushed before initialization, resulting in WARN_ON(!work->func). > > __smc_lgr_terminate | smc_connect_{rdma|ism} > ------------------------------------------------------------- > | smc_conn_create > | \- smc_lgr_register_conn > for conn in lgr->conns_all | > \- smc_conn_kill | > \- smc_close_active_abort | > \- smc_close_cancel_work | > \- cancel_work_sync | > \- __flush_work | > (close_work) | > | smc_close_init > | \- INIT_WORK(&close_work) > > So fix this by initializing close_work before establishing the > connection. > > Fixes: 46c28dbd4c23 ("net/smc: no socket state changes in tasklet context") > Fixes: 413498440e30 ("net/smc: add SMC-D support in af_smc") > Signed-off-by: Wen Gu <guwen@linux.alibaba.com> > --- > net/smc/af_smc.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c > index 9d76e902fd77..ed6d4d520bc7 100644 > --- a/net/smc/af_smc.c > +++ b/net/smc/af_smc.c > @@ -383,6 +383,7 @@ void smc_sk_init(struct net *net, struct sock *sk, int protocol) > smc->limit_smc_hs = net->smc.limit_smc_hs; > smc->use_fallback = false; /* assume rdma capability first */ > smc->fallback_rsn = 0; > + smc_close_init(smc); > } > > static struct sock *smc_sock_alloc(struct net *net, struct socket *sock, > @@ -1299,7 +1300,6 @@ static int smc_connect_rdma(struct smc_sock *smc, > goto connect_abort; > } > > - smc_close_init(smc); > smc_rx_init(smc); > > if (ini->first_contact_local) { > @@ -1435,7 +1435,6 @@ static int smc_connect_ism(struct smc_sock *smc, > goto connect_abort; > } > } > - smc_close_init(smc); > smc_rx_init(smc); > smc_tx_init(smc); > > @@ -2479,7 +2478,6 @@ static void smc_listen_work(struct work_struct *work) > goto out_decl; > > mutex_lock(&smc_server_lgr_pending); > - smc_close_init(new_smc); > smc_rx_init(new_smc); > smc_tx_init(new_smc); > Thank you for the very good commit message. Makes sense to me. Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 9d76e902fd77..ed6d4d520bc7 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -383,6 +383,7 @@ void smc_sk_init(struct net *net, struct sock *sk, int protocol) smc->limit_smc_hs = net->smc.limit_smc_hs; smc->use_fallback = false; /* assume rdma capability first */ smc->fallback_rsn = 0; + smc_close_init(smc); } static struct sock *smc_sock_alloc(struct net *net, struct socket *sock, @@ -1299,7 +1300,6 @@ static int smc_connect_rdma(struct smc_sock *smc, goto connect_abort; } - smc_close_init(smc); smc_rx_init(smc); if (ini->first_contact_local) { @@ -1435,7 +1435,6 @@ static int smc_connect_ism(struct smc_sock *smc, goto connect_abort; } } - smc_close_init(smc); smc_rx_init(smc); smc_tx_init(smc); @@ -2479,7 +2478,6 @@ static void smc_listen_work(struct work_struct *work) goto out_decl; mutex_lock(&smc_server_lgr_pending); - smc_close_init(new_smc); smc_rx_init(new_smc); smc_tx_init(new_smc);
We encountered a warning that close_work was canceled before initialization. WARNING: CPU: 7 PID: 111103 at kernel/workqueue.c:3047 __flush_work+0x19e/0x1b0 Workqueue: events smc_lgr_terminate_work [smc] RIP: 0010:__flush_work+0x19e/0x1b0 Call Trace: ? __wake_up_common+0x7a/0x190 ? work_busy+0x80/0x80 __cancel_work_timer+0xe3/0x160 smc_close_cancel_work+0x1a/0x70 [smc] smc_close_active_abort+0x207/0x360 [smc] __smc_lgr_terminate.part.38+0xc8/0x180 [smc] process_one_work+0x19e/0x340 worker_thread+0x30/0x370 ? process_one_work+0x340/0x340 kthread+0x117/0x130 ? __kthread_cancel_work+0x50/0x50 ret_from_fork+0x22/0x30 This is because when smc_close_cancel_work is triggered, e.g. the RDMA driver is rmmod and the LGR is terminated, the conn->close_work is flushed before initialization, resulting in WARN_ON(!work->func). __smc_lgr_terminate | smc_connect_{rdma|ism} ------------------------------------------------------------- | smc_conn_create | \- smc_lgr_register_conn for conn in lgr->conns_all | \- smc_conn_kill | \- smc_close_active_abort | \- smc_close_cancel_work | \- cancel_work_sync | \- __flush_work | (close_work) | | smc_close_init | \- INIT_WORK(&close_work) So fix this by initializing close_work before establishing the connection. Fixes: 46c28dbd4c23 ("net/smc: no socket state changes in tasklet context") Fixes: 413498440e30 ("net/smc: add SMC-D support in af_smc") Signed-off-by: Wen Gu <guwen@linux.alibaba.com> --- net/smc/af_smc.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)