@@ -319,7 +319,7 @@ static int proc_do_dev_weight(const struct ctl_table *table, int write,
int ret, weight;
mutex_lock(&dev_weight_mutex);
- ret = proc_dointvec(table, write, buffer, lenp, ppos);
+ ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
if (!ret && write) {
weight = READ_ONCE(weight_p);
WRITE_ONCE(net_hotdata.dev_rx_weight, weight * dev_weight_rx_bias);
@@ -412,6 +412,7 @@ static struct ctl_table net_core_table[] = {
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_do_dev_weight,
+ .extra1 = SYSCTL_ONE,
},
{
.procname = "dev_weight_rx_bias",
@@ -419,6 +420,7 @@ static struct ctl_table net_core_table[] = {
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_do_dev_weight,
+ .extra1 = SYSCTL_ONE,
},
{
.procname = "dev_weight_tx_bias",
@@ -426,6 +428,7 @@ static struct ctl_table net_core_table[] = {
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_do_dev_weight,
+ .extra1 = SYSCTL_ONE,
},
{
.procname = "netdev_max_backlog",
The following problem was encountered during stability test: (NULL net_device): NAPI poll function process_backlog+0x0/0x530 \ returned 1, exceeding its budget of 0. ------------[ cut here ]------------ list_add double add: new=ffff88905f746f48, prev=ffff88905f746f48, \ next=ffff88905f746e40. WARNING: CPU: 18 PID: 5462 at lib/list_debug.c:35 \ __list_add_valid_or_report+0xf3/0x130 CPU: 18 UID: 0 PID: 5462 Comm: ping Kdump: loaded Not tainted 6.13.0-rc7+ RIP: 0010:__list_add_valid_or_report+0xf3/0x130 Call Trace: ? __warn+0xcd/0x250 ? __list_add_valid_or_report+0xf3/0x130 enqueue_to_backlog+0x923/0x1070 netif_rx_internal+0x92/0x2b0 __netif_rx+0x15/0x170 loopback_xmit+0x2ef/0x450 dev_hard_start_xmit+0x103/0x490 __dev_queue_xmit+0xeac/0x1950 ip_finish_output2+0x6cc/0x1620 ip_output+0x161/0x270 ip_push_pending_frames+0x155/0x1a0 raw_sendmsg+0xe13/0x1550 __sys_sendto+0x3bf/0x4e0 __x64_sys_sendto+0xdc/0x1b0 do_syscall_64+0x5b/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e The reproduction command is as follows: sysctl -w net.core.dev_weight=0 Ping 127.0.0.1 This is because when the napi's weight is set to 0, process_backlog() may return 0 and clear the NAPI_STATE_SCHED bit of napi->state, causing this napi to be re-polled in net_rx_action() until __do_softirq() times out. Since the NAPI_STATE_SCHED bit has been cleared, napi_schedule_rps() can be retriggered in enqueue_to_backlog(), causing this issue. Making the napi's weight always non-zero solves this problem. Fixes: e38766054509 ("[NET]: Fix sysctl net.core.dev_weight") Fixes: 3d48b53fb2ae ("net: dev_weight: TX/RX orthogonality") Signed-off-by: Liu Jian <liujian56@huawei.com> --- net/core/sysctl_net_core.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)