3.6 Regression: kernel NULL pointer dereference inpacpi_set_dmamode

From: Anton V. Boyarshinov
Date: Thu Oct 11 2012 - 07:24:04 EST


Hello,
We have an early boot crash in 3.6 and 3.6.1 on many machines, using
nvidia chipsets. Boot fails in 1 case to 10 boots or 9 cases in 10 boots, depending on machine.

The head of log, got via serial console(full log attached):
-------------------------------------------
2.672343Ã BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
2.676024Ã IP: Ã<ffffffffa001e29c>Ã pacpi_set_dmamode+0x5c/0xc0 Ãpata_acpiÃ
2.676024Ã PGD 115076067 PUD 1167f1067 PMD 0
2.676024Ã Oops: 0000 Ã#1Ã PREEMPT SMP
2.676024Ã Modules linked in: ata_generic sata_nv pata_acpi libata scsi_mod ide_pci_generic ide_core
2.703078Ã CPU 1
2.703078Ã Pid: 644, comm: scsi_eh_2 Not tainted 3.6.1-un-def-alt2
#1 System manufacturer System Product Name/M2NPV-VM
-------------------------------------------

Disabling on-board IDE controller in BIOS seems to workarownd the problem.

Regards,
Anton

Attachment: 3.6.1-boot-crash-pacpi_set_dmamode
Description: Binary data

Attachment: config
Description: Binary data