Re: [linux-next] scsi_attach_vpd() warning at mm/page_alloc.c:2497

[James Bottomley <James.Bottomley@HansenPartnership.com>]

On Thu, 2014-03-27 at 13:19 +0300, Sergey Senozhatsky wrote:
> Hello,
> 
> [    1.971778] ------------[ cut here ]------------
> [    1.971960] WARNING: CPU: 1 PID: 6 at mm/page_alloc.c:2497 __alloc_pages_nodemask+0x1b9/0x693()
> [    1.972246] Modules linked in: sd_mod ahci
> [    1.972604] CPU: 1 PID: 6 Comm: kworker/u8:0 Not tainted 3.14.0-rc8-next-20140327-dbg-dirty #202
> [    1.972890] Hardware name: Acer             Aspire 5741G    /Aspire 5741G    , BIOS V1.20 02/08/2011
> [    1.973182] Workqueue: events_unbound async_run_entry_fn
> [    1.973417]  0000000000000000 ffff8801534d5af0 ffffffff813ad822 0000000000000000
> [    1.973994]  ffff8801534d5b28 ffffffff8103c03c ffffffff810ad4e5 00000000001000d0
> [    1.974529]  ffffffff81656fc8 0000000000000000 ffffffff81656fc0 ffff8801534d5b38
> [    1.975125] Call Trace:
> [    1.975306]  [<ffffffff813ad822>] dump_stack+0x4e/0x7a
> [    1.975488]  [<ffffffff8103c03c>] warn_slowpath_common+0x75/0x8e
> [    1.975670]  [<ffffffff810ad4e5>] ? __alloc_pages_nodemask+0x1b9/0x693
> [    1.975853]  [<ffffffff8103c0f4>] warn_slowpath_null+0x15/0x17
> [    1.976035]  [<ffffffff810ad4e5>] __alloc_pages_nodemask+0x1b9/0x693
> [    1.976220]  [<ffffffff81074220>] ? console_unlock+0x2dd/0x2fa
> [    1.976404]  [<ffffffff812a08be>] ? scsi_execute_req_flags+0x9c/0xb3
> [    1.976587]  [<ffffffff810ad9d1>] __get_free_pages+0x12/0x3f
> [    1.976771]  [<ffffffff810d5c66>] __kmalloc+0x37/0x112
> [    1.976951]  [<ffffffff8129b5f4>] scsi_attach_vpd+0x41/0x1a8
> [    1.977133]  [<ffffffff812a3d81>] scsi_probe_and_add_lun+0x8ec/0xa21
> [    1.977317]  [<ffffffff812a40f8>] __scsi_add_device+0xce/0x10a
> [    1.977501]  [<ffffffff812b109a>] ata_scsi_scan_host+0x60/0x142
> [    1.977683]  [<ffffffff812ad6e9>] async_port_probe+0x45/0x4a
> [    1.977873]  [<ffffffff81057e18>] async_run_entry_fn+0x5a/0x110
> [    1.978061]  [<ffffffff8104ee52>] process_one_work+0x1c9/0x2e9
> [    1.978243]  [<ffffffff8104f3ec>] worker_thread+0x1d3/0x2bd
> [    1.978424]  [<ffffffff8104f219>] ? rescuer_thread+0x27d/0x27d
> [    1.978606]  [<ffffffff81053ab4>] kthread+0xd6/0xde
> [    1.978786]  [<ffffffff810539de>] ? kthread_create_on_node+0x162/0x162
> [    1.978970]  [<ffffffff813b2efc>] ret_from_fork+0x7c/0xb0
> [    1.979151]  [<ffffffff810539de>] ? kthread_create_on_node+0x162/0x162
> [    1.979334] ---[ end trace ca7c5bd74b0dca21 ]---
> 
> 
> scsi_attach_vpd() (at pg0 label) attempts to firstly allocate 255 and later 134217730 bytes.

What device is this?  can you do a sg_inq -H -p 0 /dev/sda and email the
results to see if there's a code error or the device really is sending
data that's insane.

> ---
> 
> general question,
> 
> scsi_attach_vpd() is sure that scsi_vpd_inquiry() returns `ret < 0' in case of
> an error and `ret > 0' otherwise:
> 
> 	"Returns size of the vpd page on success or a negative error number."
> 
> while this is not exactly true.
> 
> scsi_vpd_inquiry() indeed can return -EINVAL, but usually it returns
> scsi_execute_req()->scsi_execute_req_flags()->scsi_execute() status, which
> has different error indication and can be, e.g. for failed blk_get_request()
> in scsi_execute() or failed sense kzalloc() in scsi_execute_req_flags(),
> `DRIVER_ERROR << 24'.

Yes, that looks to be the problem.  Can you test this patch?

James

---

diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index 3241749..c4d632c 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -952,7 +952,7 @@ static int scsi_vpd_inquiry(struct scsi_device *sdev, unsigned char *buffer,
 	result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer,
 				  len, NULL, 30 * HZ, 3, NULL);
 	if (result)
-		return result;
+		return -EIO;
 
 	/* Sanity check that we got the page back that we asked for */
 	if (buffer[1] != page)