Bug 158107

Summary:	Serial console turns into garbage after initialising 16550A
Product:	Red Hat Enterprise Linux 4	Reporter:	Kjetil T. Homme <kjetilho>
Component:	kernel	Assignee:	David Woodhouse <dwmw2>
Status:	CLOSED ERRATA	QA Contact:	Brian Brock <bbrock>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	4.0	CC:	davej, t.h.amundsen, wtogami
Target Milestone:	---
Target Release:	---
Hardware:	i686
OS:	Linux
Whiteboard:
Fixed In Version:	RHSA-2005-514	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2005-10-05 13:10:17 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	156322

Description Kjetil T. Homme 2005-05-18 18:34:55 UTC

(Bug #152385 may be related to this problem.)

when you boot the default RHEL4 kernel on Dell PowerEdge 2650 (and others) with
serial console enabled, the 8250 driver will foul up the settings during its
initialisation so that the serial driver will print nothing but garbage.

Kernel command line: ks=nfs:host:/path/ks.cfg initrd=initrd.img
ramdisk_size=8192 BOOT_IMAGE=vmlinuz console=ttyS0,9600 console=tty0

this works fine until:

serio: i8042 AUX port at 0x60,0x64 irq 12
serio: i8042 KBD port at 0x60,0x64 irq 1
Serial: 8250/16550 driver $Revision: 1.90 $ 8 ports, IRQ sharing enabled
^@%^@U^@P^@^@^@Z%$^@;^@^@t^@A?`^@~^@^@^@^@^@1^@C^@^L^@^@^@^\xZf0^D^@^_^@^@-^@

the problem has been discussed on linux-kernel, but I don't think it has been
resolved, the code remains in 2.6.11.

http://www.ussg.iu.edu/hypermail/linux/kernel/0503.3/1091.html

Comment 1 David Woodhouse 2005-05-24 10:45:42 UTC

Assuming the port is detected as a NS16550A, this is a duplicate of bug #156705.

Bug #152385 is something entirely different.

*** This bug has been marked as a duplicate of 156705 ***

Comment 2 Red Hat Bugzilla 2005-10-05 13:10:18 UTC

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