Bug 154488

Summary: /proc/partitions show bogus device files for disks that are not present
Product: Red Hat Enterprise Linux 3 Reporter: Karthik G.S.B. <gsb>
Component: kernelAssignee: Kernel Maintainer List <kernel-maint>
Status: CLOSED NOTABUG QA Contact: Brian Brock <bbrock>
Severity: medium Docs Contact:
Priority: medium    
Version: 3.0   
Target Milestone: ---   
Target Release: ---   
Hardware: i686   
OS: Linux   
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Fixed In Version: Doc Type: Bug Fix
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Clone Of: Environment:
Last Closed: 2005-04-12 08:26:46 UTC Type: ---
Regression: --- Mount Type: ---
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Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Karthik G.S.B. 2005-04-12 06:41:23 UTC
From Bugzilla Helper:
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.5) Gecko/20041107 Firefox/1.0

Description of problem:
When the user creates a fiber channel disk is removed from the linux host when the system is powered down, on reboot the linux system adds bogus device entries in /proc/partitions and tries I/O on the device.

The system under description had a qlogic driver installed (qla2300)

Example:
 /dev/sda and /dev/sdb are valid disks; here RHAS has added /dev/sd

Version-Release number of selected component (if applicable):
kernel-2.4.21-20.EL

How reproducible:
Always

Steps to Reproduce:
1. Expose two disks to the linux host over fiber-channel
2. On boot, verify that both the disks are visible /dev/sda and /dev/sdb
3. Shutdown the linux system
4. Remove the second disk
5. Boot the system
6. cat /proc/partitions

  

Actual Results:  Step1 was tried with four disks and Step4 was tried by removing two disks. The output is as follows:

#### /dev/sda and /dev/sdb contain 3 valid partitions
#### /dev/sdc and /dev/sdd are not present at all

# cat /proc/partitions
major minor  #blocks  name     rio rmerge rsect ruse wio wmerge wsect wuse running use aveq

   8     0   41943040 sda 2456 4873 56298 7990 1552 1837 27226 1760 0 7620 9750
   8     1     104391 sda1 22 106 256 90 1 0 2 0 0 90 90
   8     2   41311147 sda2 2367 4568 55450 7740 1551 1837 27224 1760 0 7430 9500
   8     3     522112 sda3 14 44 176 60 0 0 0 0 0 60 60
   8    16   41943040 sdb 114 454 1136 270 0 0 0 0 0 260 270
   8    17     104391 sdb1 19 81 200 80 0 0 0 0 0 80 80
   8    18   41311147 sdb2 18 78 192 70 0 0 0 0 0 70 70
   8    19     522112 sdb3 30 162 384 70 0 0 0 0 0 70 70
   8    32   41943040 sdc 5 15 40 10 0 0 0 0 0 10 10
   8    48   41943040 sdd 5 15 40 0 0 0 0 0 0 0 0


### I/O activity on the device /dev/sdc and /dev/sdd

# tail -10f /var/log/messages
Apr 12 10:32:57 linux kernel: Device 08:20 not ready.
Apr 12 10:32:57 linux kernel:  I/O error: dev 08:20, sector 0
Apr 12 10:32:57 linux kernel: Device 08:30 not ready.
Apr 12 10:32:57 linux kernel:  I/O error: dev 08:30, sector 0
Apr 12 10:34:19 linux kernel: Device 08:20 not ready.
Apr 12 10:34:19 linux kernel:  I/O error: dev 08:20, sector 0
Apr 12 10:34:19 linux kernel: Device 08:30 not ready.
Apr 12 10:34:19 linux kernel:  I/O error: dev 08:30, sector 0

# uptime
 10:36:50  up 9 min,  1 user,  load average: 0.00, 0.02, 0.00



### Error report from fdisk -l
### this error is always reported

# fdisk -l

Disk /dev/sda: 42.9 GB, 42949672960 bytes
255 heads, 63 sectors/track, 5221 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot    Start       End    Blocks   Id  System
/dev/sda1   *         1        13    104391   83  Linux
/dev/sda2            14      5156  41311147+  83  Linux
/dev/sda3          5157      5221    522112+  82  Linux swap

Disk /dev/sdb: 42.9 GB, 42949672960 bytes
255 heads, 63 sectors/track, 5221 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot    Start       End    Blocks   Id  System
/dev/sdb1   *         1        13    104391   83  Linux
/dev/sdb2            14      5156  41311147+  83  Linux
/dev/sdb3          5157      5221    522112+  82  Linux swap
 I/O error: dev 08:20, sector 0     <------------   [ for /dev/sdc ]
 I/O error: dev 08:30, sector 0     <------------   [ for /dev/sdd ]



Expected Results:  1. fdisk -l or cat /proc/partitions need not list the entries
2. No error I/O on those false devices


Additional info:

# cat /etc/issue
Red Hat Enterprise Linux AS release 3 (Taroon Update 3)

Comment 1 Karthik G.S.B. 2005-04-12 08:26:46 UTC
I would like to recall this problem as this was due to multiple paths from the
host to the same disk. This was detected from kudzu hwinfo.

Thanks.