2.2.19pre14 VP3 + Quantum: dma on hangs

[Pekka Savola]

Hello all,

Using 2.2.19pre14 with:
 * software raid
 * raid1 readbalancing
 * i2c
 * lm_sensors
 * ipsec

My drives are as follows:

hda: QUANTUM FIREBALLP AS20.5, 19595MB w/1902kB Cache, CHS=2498/255/63
hdc: QUANTUM FIREBALLP AS20.5, 19595MB w/1902kB Cache, CHS=39813/16/63
hdd: IBM-DTTA-350840, 8063MB w/467kB Cache, CHS=16383/16/63
hdb: ATAPI 4X CD-ROM drive, 256kB Cache

[ Bios sees: HDA & HDC : udma5, HDD: udma2 ]

And the mainboard related stuff in lspci:

00:00.0 Host bridge: VIA Technologies, Inc. VT82C598 [Apollo MVP3] (rev 04)
00:01.0 PCI bridge: VIA Technologies, Inc. VT82C598 [Apollo MVP3 AGP]
00:07.0 ISA bridge: VIA Technologies, Inc. VT82C586/A/B PCI-to-ISA [Apollo VP] (rev 47)
00:07.1 IDE interface: VIA Technologies, Inc. VT82C586 IDE [Apollo] (rev 06)
00:07.2 USB Controller: VIA Technologies, Inc. VT82C586B USB (rev 02)
00:07.3 Bridge: VIA Technologies, Inc. VT82C586B ACPI (rev 10)

Now, if I turn on dma on hdd, and run hdparm benchmark, everything works
fine.

If I turn on dma with hdparm on hda or hdc, next disk activity will freeze
the system completely.  No keyboard interaction, not anything.  Only reset
helps.

Also, if I disable UDMA in bios completely on hda and hdc, hdparm will
work, but the speed is awful (only ~6 MB/s) even if DMA is enabled.

The most relevant kernel settings are, I think:

CONFIG_BLK_DEV_IDEDMA=y
# CONFIG_BLK_DEV_OFFBOARD is not set
CONFIG_IDEDMA_AUTO=y
# CONFIG_BLK_DEV_OPTI621 is not set
# CONFIG_BLK_DEV_ALI15X3 is not set
# CONFIG_BLK_DEV_TRM290 is not set
# CONFIG_BLK_DEV_NS87415 is not set
CONFIG_BLK_DEV_VIA82C586=y
# CONFIG_BLK_DEV_CMD646 is not set
# CONFIG_BLK_DEV_CS5530 is not set
# CONFIG_IDE_CHIPSETS is not set

Any ideas?

Please Cc:
-- 
Pekka Savola                  "Tell me of difficulties surmounted,
Netcore Oy                    not those you stumble over and fall"
Systems. Networks. Security.   -- Robert Jordan: A Crown of Swords