Bug 1047376 - blkid hangs while reading from /dev/fd0
Summary: blkid hangs while reading from /dev/fd0
Alias: None
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: util-linux
Version: 7.0
Hardware: Unspecified
OS: Unspecified
Target Milestone: rc
: ---
Assignee: Karel Zak
QA Contact: Leos Pol
: 1081567 1082961 (view as bug list)
Depends On:
Blocks: RHEL7CCC 1080727
TreeView+ depends on / blocked
Reported: 2013-12-30 19:10 UTC by Berkley Shands
Modified: 2014-06-18 04:12 UTC (History)
9 users (show)

Fixed In Version: util-linux-2.23.2-16.el7
Doc Type: Bug Fix
Doc Text:
Clone Of:
Last Closed: 2014-06-13 11:08:56 UTC
Target Upstream Version:

Attachments (Terms of Use)
blkid_debug (3.68 KB, text/plain)
2014-03-18 15:54 UTC, Pavel Holica
no flags Details
partitions (418 bytes, text/plain)
2014-03-18 15:54 UTC, Pavel Holica
no flags Details

Description Berkley Shands 2013-12-30 19:10:02 UTC
Description of problem:
Installing on an old SuperMicro H8DCE 2-socket AMD 940 motherboard
With ForcedEth ethernet, floppy controller enabled, but *NO* floppy
powered. Late stage install of boot block fails with grub2-install step hanging
attempting to access the floppy FD0, which in this case, does not exist.
The retry does not time out even after 30 minutes.

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

How reproducible:

Install general workstation development on old AMD socket 940 motherboard.
Leave the floppy drive unpowered.

Steps to Reproduce:

Actual results:

Hang in grub2- step trying for a floppy. <Alt><F4>
 shows grub2 step, and scrolling FD0 errors.

Expected results:

A grub2 boot block

Additional info:

Yeah, its old and in the way, but it didn't cost much :-)
The forcedeth is not a valid ethernet device either (also no big deal).

Comment 2 Pavel Holica 2014-03-17 12:10:34 UTC
I was able to reproduce the issue, and it was caused by blkid which is run inside os /bin/os-prober in function partitions.

Changing component to util-linux. blkid was from: util-linux-2.23.2-14.el7

Comment 5 Leos Pol 2014-03-18 14:15:46 UTC
Any progress with this?

Comment 6 Karel Zak 2014-03-18 14:54:57 UTC
It would be nice to have /proc/partitions from the machine. libblkid should not read fd0 by default at all. It would be also nice to have output from

 LIBBLKID_DEBUG=0xffff blkid

Comment 7 Pavel Holica 2014-03-18 15:54:08 UTC
Created attachment 876011 [details]

Comment 8 Pavel Holica 2014-03-18 15:54:11 UTC
Created attachment 876012 [details]

Comment 9 Karel Zak 2014-03-19 09:28:47 UTC
Hmm... it seems that we're affected by stupid kernel regression (which will not be fixed...), see


where kernel displays removable media in /proc/partitions now.

It will be probably necessary to add an extra filter to libblkid to ignore by default the floppies.

Comment 10 Karel Zak 2014-03-20 09:38:56 UTC
The another story are mess in return codes in the library. It should be fixed together with the floppy problem.

Comment 11 Karel Zak 2014-03-20 10:28:14 UTC
Note that there is also kernel solution, see bug #1078786.

Comment 12 Karel Zak 2014-03-24 10:40:25 UTC
Fixed by upstream commits 296d96e20e565e497e9510e6ac9b71e0a0ca447d and 37f4060225df0591ab8e1dd676dbc8115d900d4f.

Comment 17 Karel Zak 2014-03-28 13:38:24 UTC
*** Bug 1081567 has been marked as a duplicate of this bug. ***

Comment 20 Miroslav Vadkerti 2014-04-01 08:09:20 UTC
*** Bug 1082961 has been marked as a duplicate of this bug. ***

Comment 23 Ludek Smid 2014-06-13 11:08:56 UTC
This request was resolved in Red Hat Enterprise Linux 7.0.

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