Bug 68286

Summary: Unable to use DMA
Product: [Retired] Red Hat Linux Reporter: Samuel Flory <sflory>
Component: kernelAssignee: Arjan van de Ven <arjanv>
Status: CLOSED CURRENTRELEASE QA Contact: Brian Brock <bbrock>
Severity: medium Docs Contact:
Priority: medium    
Version: 8.0CC: alan
Target Milestone: ---   
Target Release: ---   
Hardware: i386   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2003-06-05 17:57:00 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Samuel Flory 2002-07-08 20:48:01 UTC
From Bugzilla Helper:
User-Agent: Mozilla/5.0 Galeon/1.2.5 (X11; Linux i686; U;) Gecko/0

Description of problem:
Both the Tyan 2515, and 2518 don't enable dma by default.You can enable it via
hdparm, but the kernel prints  a lot of errors, and reverts to non dma access. 
Both systems can use dma under RH7.2, 2.4.18, and 2.4.19rc1.

Version-Release number of selected component (if applicable):


How reproducible:
Always

Steps to Reproduce:
1.install limbo
2.hdparm -d 1 /dev/hda
3.
	

Actual Results:  From dmesg:
hdc: timeout waiting for DMA
ide_dmaproc: chipset supported ide_dma_timeout func only: 14
hdc: status error: status=0x58 { DriveReady SeekComplete DataRequest }
hdc: drive not ready for command
hdc: timeout waiting for DMA
ide_dmaproc: chipset supported ide_dma_timeout func only: 14
hdc: status error: status=0x58 { DriveReady SeekComplete DataRequest }
hdc: drive not ready for command
hdc: timeout waiting for DMA
ide_dmaproc: chipset supported ide_dma_timeout func only: 14
hdc: status error: status=0x58 { DriveReady SeekComplete DataRequest }
hdc: drive not ready for command
hdc: timeout waiting for DMA
ide_dmaproc: chipset supported ide_dma_timeout func only: 14
hdc: status error: status=0x58 { DriveReady SeekComplete DataRequest }
hdc: drive not ready for command
hda: timeout waiting for DMA
ide_dmaproc: chipset supported ide_dma_timeout func only: 14
hda: status error: status=0x58 { DriveReady SeekComplete DataRequest }
hda: drive not ready for command
hda: timeout waiting for DMA
ide_dmaproc: chipset supported ide_dma_timeout func only: 14
hda: status error: status=0x58 { DriveReady SeekComplete DataRequest }
hda: drive not ready for command
hda: timeout waiting for DMA
ide_dmaproc: chipset supported ide_dma_timeout func only: 14
hda: status error: status=0x58 { DriveReady SeekComplete DataRequest }
hda: drive not ready for command
hda: timeout waiting for DMA
ide_dmaproc: chipset supported ide_dma_timeout func only: 14
hda: status error: status=0x58 { DriveReady SeekComplete DataRequest }
hda: drive not ready for command



Additional info:

Comment 1 Arjan van de Ven 2002-07-31 14:14:54 UTC
any idea what kind of ide chipset this is?

Comment 2 Samuel Flory 2002-07-31 23:30:34 UTC
SvrWks OSB4: IDE controller on PCI bus 00 dev 79
SvrWks OSB4: chipset revision 0
SvrWks OSB4: not 100% native mode: will probe irqs later
    ide0: BM-DMA at 0xffa0-0xffa7, BIOS settings: hda:DMA, hdb:pio
    ide1: BM-DMA at 0xffa8-0xffaf, BIOS settings: hdc:DMA, hdd:pio


  Note I have not tested the current beta on this system yet.

Comment 3 Arjan van de Ven 2002-08-01 08:23:30 UTC
OSB4.... yes DMA is disabled on purpose; there's a silicon bug that can lead to
random memory corruption

Comment 4 Alan Cox 2002-08-01 12:24:41 UTC
We should only be cutting out UDMA. It also doesnt explain why using hdparm -d 1
failed. That should most definitely have worked.

The rule is approximately

CSB5/CSB6 -> UDMA OK
OSB4 -> UDMA off for certain subsets of drives (safest to say for all),
        MWDMA works fine, as does PIO





Comment 5 Samuel Flory 2002-08-16 19:19:32 UTC
  This also occurs on a tyan 2510 /w the same OSB4 chipset.

  In addition the 2518, and 2510 seem to work fine on 7.2 (/w multiword dma),
and under Alan's 2.4.20-pre2-ac3.  (Fine = 24H of cerberus in pathological mode.)

Comment 6 Alan Cox 2002-08-17 18:07:39 UTC
Thats newer IDE code and being a little less conservative. Until we are sure we
have the problem entirely under control its not reasonable to ship DMA enabled
OSB4 to end users