ADD 802626 - Infinite cpu loop in _pagebuf_handle_iovecs

[pv@xxxxxxxxxxxxx (lord@xxxxxxx)]

View Incident: 
http://co-op.engr.sgi.com/BugWorks/code/bwxquery.cgi?search=Search&wlong=1&view_type=Bug&wi=802626

 Status : open                         Priority : 1                         
 Assigned Engineer : nb                Submitter : lord                     
*Modified User : lord                 *Modified User Domain : sgi.com       
*Description :
Running doio on xfs managed to produce a number of cases of 
read calls getting into a cpu loop in _pagebuf_handle_iovecs

Stack traceback for pid 1299
    EBP       EIP         Function(args)
0xc1decf94 0xf8825c22 [pagebuf]_pagebuf_handle_iovecs+0xd2 (0xdda75ee0, 
0xc1decf94, 0x0, 0x19000, 0x0)
                               pagebuf .text 0xf8823060 0xf8825b50 0xf8825d90
0xdda75e6c 0xf882649d [pagebuf]_pagebuf_read_helper+0x25 (0xdda75ee0, 
0xc1decf94, 0x0, 0x1000)
                               pagebuf .text 0xf8823060 0xf8826478 0xf88264a8
0xdda75eac 0xc012773b do_generic_file_read+0x207 (0xf48f6e60, 0xf48f6e80, 
0xdda75ee0, 0xf8826478)

.....


==========================
ADDITIONAL INFORMATION (ADD)
From: lord@xxxxxxx (BugWorks)
Date: Sep 22 2000 08:30:01AM
==========================

Filesystem was mounted without any kio options, so it is buffer
head based. Here is a longer version of the arguments for
_pagebuf_handle_iovecs

0xdda75e3c 0xf8825c2a [pagebuf]_pagebuf_handle_iovecs+0xda (0xdda75ee0, 
0xc1decf94, 0x0, 0x19000, 0x0, 0x1000, 0x1)