Microsoft KB Archive/328468

= Infinite loop occurs when the serial port is unexpectedly removed on a Windows 2000-based computer =

Article ID: 328468

Article Last Modified on 2/20/2007

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APPLIES TO


 * Microsoft Windows 2000 Server
 * Microsoft Windows 2000 Professional Edition
 * Microsoft Windows 2000 Advanced Server

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This article was previously published under Q328468





SYMPTOMS
If you disconnect a serial port while the serial port driver is reading data from a universal asynchronous receiver-transmitter (UART)-based serial device, the standard Microsoft serial port driver can enter an infinite loop in its interrupt service routine on a Microsoft Windows 2000-based computer.

You may receive the following Stop error:

- 1: kd> .bugcheck Bugcheck code 000000CA Arguments 00000003 8b06c670 e25933c8 00000001 1: kd> k ChildEBP RetAddr f6853c2c 80424be6 nt!IopProcessNewDeviceNode+0x89 f6853c3c 804b7da4 nt!IopProcessNewChildren+0x22 f6853c60 804b7b8f nt!IopEnumerateDevice+0x20a f6853c9c 804b798a nt!IopStartAndEnumerateDevice+0x1c3 f6853cbc 804be655 nt!IopProcessStartDevicesWorker+0x72 f6853ccc 804b796d nt!IopForAllChildDeviceNodes+0x1f f6853cf0 804b78bb nt!IopProcessStartDevicesWorker+0x55 f6853d0c 804b7860 nt!IopProcessStartDevices+0x43 f6853d30 80424a8f nt!IopBusCheck+0x78 f6853d78 80416f53 nt!IopDeviceActionWorker+0x40f f6853da8 80454fde nt!ExpWorkerThread+0xaf f6853ddc 8046a302 nt!PspSystemThreadStartup+0x54 00000000 00000000 nt!KiThreadStartup+0x16



CAUSE
This problem occurs when a serial port is removed from the computer while the computer is running. The serial port driver performs a test loop until the Line Status Register clears its Read bit.



Hotfix information
A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that this article describes. Apply it only to systems that are experiencing this specific problem.

To resolve this problem, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/contactus/?ws=support

Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

Prerequisites
No prerequisites are required.

Restart requirement
You do not have to restart your computer after you apply this hotfix.

Hotfix replacement information
This hotfix does not replace any other hotfixes.

File information
The English version of this hotfix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel. Date        Time   Version            Size    File name -- 21-Sep-2003 00:36  5.0.2195.6824      14,160  Serenum.sys 21-Sep-2003 00:35  5.0.2195.6824      60,880  Serial.sys



STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the &quot;Applies to&quot; section of this article.



MORE INFORMATION
For additional information, click the following article numbers to view the articles in the Microsoft Knowledge Base:

816915 New file naming schema for Microsoft Windows software update packages

824684 Description of the standard terminology that is used to describe Microsoft software updates

Additional query words: serial port

Keywords: kbhotfixserver kbqfe kbbug kbfix kbqfe kbwin2000presp5fix KB328468

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