Processes receive SIGSEGV if TCQ is enabled

From: Thomas Schlichter
Date: Thu Oct 30 2003 - 10:03:17 EST


Hello,

today I tried to test TCQ with the linux-2.6.0-test9-mm1 kernel. The config.gz
is attached. But after enabling TCQ with 'hdparm -Q1 /dev/hda' newly started
processes die due to a received SIGSEGV. No bad kernel messages appear...

Disabling TCQ again doesn't help, only e reboot does...
When I let the kernel enable TCQ at boot time, it set the TCQ buffer depth to
8 and even the init script was killed!

Here some additional information:

schlicht@bigboss:~> uname -a
Linux bigboss 2.6.0-test9-mm1 #1 Thu Oct 30 14:45:35 CET 2003 i686 unknown
unknown GNU/Linux
schlicht@bigboss:~> hdparm -i /dev/hda

/dev/hda:

Model=IBM-DTLA-307030, FwRev=TX4OA50C, SerialNo=YK0YKT61943
Config={ HardSect NotMFM HdSw>15uSec Fixed DTR>10Mbs }
RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=40
BuffType=DualPortCache, BuffSize=1916kB, MaxMultSect=16, MultSect=16
CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=60036480
IORDY=on/off, tPIO={min:240,w/IORDY:120}, tDMA={min:120,rec:120}
PIO modes: pio0 pio1 pio2 pio3 pio4
DMA modes: mdma0 mdma1 mdma2
UDMA modes: udma0 udma1 udma2 udma3 udma4 *udma5
AdvancedPM=yes: disabled (255) WriteCache=enabled
Drive conforms to: ATA/ATAPI-5 T13 1321D revision 1:

* signifies the current active mode

schlicht@bigboss:~> hdparm -i /dev/hdb
/dev/hdb: No such device or address
schlicht@bigboss:~> cat /proc/ide/via
----------VIA BusMastering IDE Configuration----------------
Driver Version: 3.38
South Bridge: VIA vt8235
Revision: ISA 0x0 IDE 0x6
Highest DMA rate: UDMA133
BM-DMA base: 0xec00
PCI clock: 33.3MHz
Master Read Cycle IRDY: 0ws
Master Write Cycle IRDY: 0ws
BM IDE Status Register Read Retry: yes
Max DRDY Pulse Width: No limit
-----------------------Primary IDE-------Secondary IDE------
Read DMA FIFO flush: yes yes
End Sector FIFO flush: no no
Prefetch Buffer: yes yes
Post Write Buffer: yes yes
Enabled: yes yes
Simplex only: no no
Cable Type: 80w 40w
-------------------drive0----drive1----drive2----drive3-----
Transfer Mode: UDMA PIO DMA UDMA
Address Setup: 120ns 120ns 120ns 120ns
Cmd Active: 90ns 90ns 90ns 90ns
Cmd Recovery: 30ns 30ns 30ns 30ns
Data Active: 90ns 330ns 90ns 90ns
Data Recovery: 30ns 270ns 30ns 30ns
Cycle Time: 22ns 600ns 120ns 60ns
Transfer Rate: 88.8MB/s 3.3MB/s 16.6MB/s 33.3MB/s
schlicht@bigboss:~> mount
/dev/hda5 on / type reiserfs (rw)
proc on /proc type proc (rw)
devpts on /dev/pts type devpts (rw,mode=0620,gid=5)
sysfs on /sys type sysfs (rw)
tmpfs on /tmp type tmpfs (rw)


Regards
Thomas

P.S.: My hdparm version v5.4 sets the queuing depth only to 1 even if I
provide e.g. '-Q8'...

Attachment: config.gz
Description: GNU Zip compressed data

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Description: signature