diff options
authorLeon Yu <leoyu@nvidia.com>2020-05-22 23:29:43 +0800
committerDavid S. Miller <davem@davemloft.net>2020-05-23 16:30:27 -0700
commit31096c3e8b1163c6e966bf4d1f36d8b699008f84 (patch)
parentef24d6c3d6965158dfe23ae961d87e9a343e18a2 (diff)
net: stmmac: don't attach interface until resume finishes
Commit 14b41a2959fb ("net: stmmac: Delete txtimer in suspend") was the first attempt to fix a race between mod_timer() and setup_timer() during stmmac_resume(). However the issue still exists as the commit only addressed half of the issue. Same race can still happen as stmmac_resume() re-attaches interface way too early - even before hardware is fully initialized. Worse, doing so allows network traffic to restart and stmmac_tx_timer_arm() being called in the middle of stmmac_resume(), which re-init tx timers in stmmac_init_coalesce(). timer_list will be corrupted and system crashes as a result of race between mod_timer() and setup_timer(). systemd--1995 2.... 552950018us : stmmac_suspend: 4994 ksoftirq-9 0..s2 553123133us : stmmac_tx_timer_arm: 2276 systemd--1995 0.... 553127896us : stmmac_resume: 5101 systemd--320 7...2 553132752us : stmmac_tx_timer_arm: 2276 (sd-exec-1999 5...2 553135204us : stmmac_tx_timer_arm: 2276 --------------------------------- pc : run_timer_softirq+0x468/0x5e0 lr : run_timer_softirq+0x570/0x5e0 Call trace: run_timer_softirq+0x468/0x5e0 __do_softirq+0x124/0x398 irq_exit+0xd8/0xe0 __handle_domain_irq+0x6c/0xc0 gic_handle_irq+0x60/0xb0 el1_irq+0xb8/0x180 arch_cpu_idle+0x38/0x230 default_idle_call+0x24/0x3c do_idle+0x1e0/0x2b8 cpu_startup_entry+0x28/0x48 secondary_start_kernel+0x1b4/0x208 Fix this by deferring netif_device_attach() to the end of stmmac_resume(). Signed-off-by: Leon Yu <leoyu@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index a999d6b33a64..1f319c9cee46 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -5190,8 +5190,6 @@ int stmmac_resume(struct device *dev)
return ret;
- netif_device_attach(ndev);
@@ -5218,6 +5216,8 @@ int stmmac_resume(struct device *dev)
phylink_mac_change(priv->phylink, true);
+ netif_device_attach(ndev);
return 0;