Description of problem: With an attached SCSI device, rmmod'ing the aic79xx module causes kernel panic. Version-Release number of selected component (if applicable): kernel-2.6.13-1.1532_FC4 How reproducible: Always. Steps to Reproduce: 1. Attach SCSI device 2. # modprobe aic79xx 3. # rmmod aic79xx Actual results: /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 an attachment] Expected results: Kernel should unload module. Additional info: * 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 production environment). * 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 (SysRq-S) syncing.
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. Thank you.