This service will be undergoing maintenance at 00:00 UTC, 2017-10-23 It is expected to last about 30 minutes
Bug 156705 - Serial console corrupt on boot
Serial console corrupt on boot
Status: CLOSED ERRATA
Product: Red Hat Enterprise Linux 4
Classification: Red Hat
Component: kernel (Show other bugs)
4.0
i386 Linux
medium Severity medium
: ---
: ---
Assigned To: Jason Baron
Brian Brock
:
: 167117 (view as bug list)
Depends On:
Blocks: 156322
  Show dependency treegraph
 
Reported: 2005-05-03 11:04 EDT by David Woodhouse
Modified: 2013-03-06 00:58 EST (History)
4 users (show)

See Also:
Fixed In Version: RHSA-2005-514
Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of:
Environment:
Last Closed: 2005-10-05 09:04:45 EDT
Type: ---
Regression: ---
Mount Type: ---
Documentation: ---
CRM:
Verified Versions:
Category: ---
oVirt Team: ---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---


Attachments (Terms of Use)
patch to recalculate divisor as appropriate. (972 bytes, patch)
2005-05-03 11:04 EDT, David Woodhouse
no flags Details | Diff
Updated patch (1.78 KB, patch)
2005-05-06 06:06 EDT, David Woodhouse
no flags Details | Diff

  None (edit)
Description David Woodhouse 2005-05-03 11:04:31 EDT
When booting with serial console on a machine with a National Semiconductor
SuperIO chip where the BIOS enables its high speed mode, the initialisation of
the serial driver switches it into high-speed mode without fixing up the baud rate. 

The result is that the port suddenly ends up running four times faster than it
should, and the last non-garbage thing we see on the serial console is the
serial driver's initialisation message.

The fix is to adjust the baud rate divisor at the same time as we adjust the
master clock...
Comment 1 David Woodhouse 2005-05-03 11:04:31 EDT
Created attachment 113967 [details]
patch to recalculate divisor as appropriate.
Comment 2 David Woodhouse 2005-05-06 06:06:05 EDT
Created attachment 114075 [details]
Updated patch

This is the form in which the patch was sent upstream. With the original
problem fixed, the 'ifndef ppc' hack isn't required either.
Comment 3 David Woodhouse 2005-05-24 06:46:01 EDT
*** Bug 158107 has been marked as a duplicate of this bug. ***
Comment 4 Kjetil T. Homme 2005-06-15 18:42:51 EDT
we added this to /etc/rc.sysinit as a workaround:

/bin/setserial /dev/ttyS0 spd_normal
/bin/stty 9600 < /dev/ttyS0

quite early, just after ". /etc/init.d/functions" worked for us.  we don't get
all the boot messages, but it's workable.

Comment 9 Red Hat Bugzilla 2005-10-05 09:04:45 EDT
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHSA-2005-514.html
Comment 10 David Woodhouse 2005-10-11 10:08:47 EDT
*** Bug 167117 has been marked as a duplicate of this bug. ***

Note You need to log in before you can comment on or make changes to this bug.