Re: [PATCH net-next] xen-netfront: fix warn message as irq device name has '/'

[Juergen Gross]

On 09/08/18 08:03, Xiao Liang wrote:
> There is a call trace generated after commit 2d408c0d4574b01b9ed45e02516888bf925e11a9(
> xen-netfront: fix queue name setting). There is no 'device/vif/xx-q0-tx' file found
> under /proc/irq/xx/.
> 
> This patch only picks up device type and id as its name.
> 
> With the patch, now /proc/interrupts looks like and the warning message gone:
>  70:         21          0          0          0   xen-dyn    -event     vif0-q0-tx
>  71:         15          0          0          0   xen-dyn    -event     vif0-q0-rx
>  72:         14          0          0          0   xen-dyn    -event     vif0-q1-tx
>  73:         33          0          0          0   xen-dyn    -event     vif0-q1-rx
>  74:         12          0          0          0   xen-dyn    -event     vif0-q2-tx
>  75:         24          0          0          0   xen-dyn    -event     vif0-q2-rx
>  76:         19          0          0          0   xen-dyn    -event     vif0-q3-tx
>  77:         21          0          0          0   xen-dyn    -event     vif0-q3-rx
> 
> Below is call trace information without this patch:
> 
> name 'device/vif/0-q0-tx'
> WARNING: CPU: 2 PID: 37 at fs/proc/generic.c:174 __xlate_proc_name+0x85/0xa0
> RIP: 0010:__xlate_proc_name+0x85/0xa0
> RSP: 0018:ffffb85c40473c18 EFLAGS: 00010286
> RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000000006
> RDX: 0000000000000007 RSI: 0000000000000096 RDI: ffff984c7f516930
> RBP: ffffb85c40473cb8 R08: 000000000000002c R09: 0000000000000229
> R10: 0000000000000000 R11: 0000000000000001 R12: ffffb85c40473c98
> R13: ffffb85c40473cb8 R14: ffffb85c40473c50 R15: 0000000000000000
> FS:  0000000000000000(0000) GS:ffff984c7f500000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f69b6899038 CR3: 000000001c20a006 CR4: 00000000001606e0
> Call Trace:
> __proc_create+0x45/0x230
> ? snprintf+0x49/0x60
> proc_mkdir_data+0x35/0x90
> register_handler_proc+0xef/0x110
> ? proc_register+0xfc/0x110
> ? proc_create_data+0x70/0xb0
> __setup_irq+0x39b/0x660
> ? request_threaded_irq+0xad/0x160
> request_threaded_irq+0xf5/0x160
> ? xennet_tx_buf_gc+0x1d0/0x1d0 [xen_netfront]
> bind_evtchn_to_irqhandler+0x3d/0x70
> ? xenbus_alloc_evtchn+0x41/0xa0
> netback_changed+0xa46/0xcda [xen_netfront]
> ? find_watch+0x40/0x40
> xenwatch_thread+0xc5/0x160
> ? finish_wait+0x80/0x80
> kthread+0x112/0x130
> ? kthread_create_worker_on_cpu+0x70/0x70
> ret_from_fork+0x35/0x40
> Code: 81 5c 00 48 85 c0 75 cc 5b 49 89 2e 31 c0 5d 4d 89 3c 24 41 5c 41 5d 41 5e 41 5f c3 4c 89 ee 48 c7 c7 40 4f 0e b4 e8 65 ea d8 ff <0f> 0b b8 fe ff ff ff 5b 5d 41 5c 41 5d 41 5e 41 5f c3 66 0f 1f
> ---[ end trace 650e5561b0caab3a ]---
> 
> Signed-off-by: Xiao Liang <xiliang@xxxxxxxxxx>
> ---
>  drivers/net/xen-netfront.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
> index 799cba4624a5..6f40df4a452e 100644
> --- a/drivers/net/xen-netfront.c
> +++ b/drivers/net/xen-netfront.c
> @@ -1604,14 +1604,16 @@ static int xennet_init_queue(struct netfront_queue *queue)
>  {
>  	unsigned short i;
>  	int err = 0;
> +	int devid = 0;
>  
>  	spin_lock_init(&queue->tx_lock);
>  	spin_lock_init(&queue->rx_lock);
>  
>  	timer_setup(&queue->rx_refill_timer, rx_refill_timeout, 0);
>  
> -	snprintf(queue->name, sizeof(queue->name), "%s-q%u",
> -		 queue->info->xbdev->nodename, queue->id);
> +	kstrtoint(strrchr(queue->info->xbdev->nodename,'/')+1, 10, &devid);

Please add blanks before '/' and around the +.

With that you can add my:

Reviewed-by: Juergen Gross <jgross@xxxxxxxx>


Juergen