Bug 13678

Summary:	hard lockup's on tsleep in atapi_queue_cmd called at splbio from afd_start from afd_strategy
Product:	Base System	Reporter:	Vsevolod Lobko <seva>
Component:	kern	Assignee:	Søren Schmidt <sos>
Status:	Closed FIXED
Severity:	Affects Only Me
Priority:	Normal
Version:	4.0-CURRENT
Hardware:	Any
OS:	Any

Description Vsevolod Lobko 1999-09-10 12:00:01 UTC

I'm trying to get working Fujitsu ATAPI MO drive, using atapi-fd driver
from new-ata
Drive in general working fine, but sometime machine hard locks on drive
access
Using NMI, i get kernel debugger prompt, and ps show mount process
sleeping on "atprq", stack trace of process show sequence of calls 
afdstrategy->afd_start->atapi_queue_cmd->tsleep

Unfortunately serial console does not work in this case, so I can't attach 
precise stack trace

Fix: 

may be by inserting splx() before queue_atapi_cmd ()?
atapi_queue_cmd do own splbio()/splx() locking
How-To-Repeat: 
Machine hard locks after several 

mount_msdos /dev/afd0 /ftp/data
umount /ftp/data

especially with concurent serial port activity (may be any interrupt
activity)

Comment 1 Sheldon Hearn freebsd_committer

1999-09-10 12:34:54 UTC

Responsible Changed
From-To: freebsd-bugs->sos

Over to the new atapi driver's author.

Comment 2 Søren Schmidt freebsd_committer

2000-02-28 19:29:38 UTC

State Changed
From-To: open->closed

There is no MO support in 4.0. 
This is being worked on, but the problem described here is fixed in 4.0.