Red Hat Bugzilla – Bug 171957
rmmod aic79xx causes kernel panic
Last modified: 2007-11-30 17:11:16 EST
Description of problem:
With an attached SCSI device, rmmod'ing the aic79xx module causes kernel panic.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Attach SCSI device
2. # modprobe aic79xx
3. # rmmod aic79xx
/var/log/messages displays "kernel: Synchronizing SCSI cache for disk sda:"
and oopses after approx. 5-7 seconds.
The oops is displayed on-screen, but not written to /var/log/messages (located
on IDE bootdisk).
[note : after the weekend, I'll take a digital image of the screen, and post as
Kernel should unload module.
* As long as no SCSI device has been attached when loading the aic79xx,
unloading works OK.
* Reason for rmmod'ing : Attached to SCSI card is a JetStor RAID array. When the
array is expanded, an rmmod is needed to let the kernel recognize the enlarged
disk geometry (the alternative is a reboot, which is not always an option in a
* SCSI card is an Adaptec 29320LP :
# cat /proc/scsi/aic79xx/0
Adaptec AIC79xx driver version: 1.3.11
Adaptec 29320LP Ultra320 SCSI adapter
aic7901A: Ultra320 Wide Channel A, SCSI Id=7, PCI 33 or 66Mhz, 512 SCBs
Allocated SCBs: 4, SG List Length: 128
* Tested with :
- both Adaptec 29320LP (BIOS 4.10.0S) and 29320ALP (BIOS 4.30.1)
- in different PCI slots
- with and without kernel boot parameter "acpi=nopci"
* Not yet tested on RHEL AS4 (hesitant to lock up my production servers).
According to http://www.ussg.iu.edu/hypermail/linux/kernel/0409.3/1247.html,
aic79xx 1.3.11 dates from 2003 and is quite stale.
Most recent version (http://people.freebsd.org/~gibbs/linux/SRC/ , kindly
appointed to it by Justin Gibbs) has its share of problems too, appearantly.
Possible fix in http://lkml.org/lkml/2005/10/3/106 (James Bottomley) for 2.6.14-rc4.
I'm fully prepared to test this with a Fedora Rawhide kernel, but as this setup
(Adaptec 29320ALP + SCSI RAID) will be moved to a production environment, is
there any chance the fix will be propagated to RHEL4 on (relatively) short notice ?
- Is it useful to follow up on this bug ?
- Should I file an RFE on RHEL, referring to this bug ?
Additional remarks :
- "rmmod aic79xx" confirmed fixed in rawhide 2.6.14-1.1632_FC5 ;
- subsequent "modprobe aic79xx" oopses kernel.
Created attachment 120513 [details]
kernel trace from kernel-2.6.14-1.1632_FC5kdump
Oct 28 18:21:40 : "# rmmod aic79xx"
Oct 28 18:22:00 : "# modprobe aic79xx"
Created attachment 120633 [details]
screen dump from 2.6.13-1.1532_FC4 kernel oops
As indicated in the original bug report, I'm providing a screen dump (initlevel
1) of the kernel panic when rmmod'ing aic79xx with attached SCSI device.
Appearantly, the system hangs after the rmmod, and oopses when manually
Seems to be fixed in 2.6.14-1.1636_FC4 .
2.6.14-1.1637_FC4 has been released as an update for FC4.
Please retest with this update, as a large amount of code has been changed in
this release, which may have fixed your problem.