Date: Fri, 12 Mar 2010 15:16:22 GMT From: Uniballer <nobody@igetenoughspamthanku.org> To: freebsd-gnats-submit@FreeBSD.org Subject: misc/144696: tcdrain(3) does not work right with uart(4) driver Message-ID: <201003121516.o2CFGMKu002632@www.freebsd.org> Resent-Message-ID: <201003121520.o2CFK1mF029956@freefall.freebsd.org>
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>Number: 144696 >Category: misc >Synopsis: tcdrain(3) does not work right with uart(4) driver >Confidential: no >Severity: serious >Priority: high >Responsible: freebsd-bugs >State: open >Quarter: >Keywords: >Date-Required: >Class: sw-bug >Submitter-Id: current-users >Arrival-Date: Fri Mar 12 15:20:01 UTC 2010 >Closed-Date: >Last-Modified: >Originator: Uniballer >Release: 8.0-RELEASE-p2 >Organization: >Environment: FreeBSD ????.xxxx.com 8.0-RELEASE-p2 FreeBSD 8.0-RELEASE-p2 #0: Tue Jan 5 16:02:27 UTC 2010 root@i386-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC i386 >Description: tcdrain(3) does not wait for serial output to complete when used with the uart(4) driver. This worked correctly on 6.4 and 7.x with the sio(4) driver. >How-To-Repeat: Loop back a serial port, write a long buffer to it, then call tcdrain(3) to wait for output to complete, and call tcflush(3) to get rid of the data. A subsequent read will show that part of the data is in the receive buffer, probably because it was received after tcflush(3) was called because tcdrain(3) was called early. See http://forums.freebsd.org/showthread.php?t=12154 for more info and sample code. >Fix: >Release-Note: >Audit-Trail: >Unformatted:
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