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Date: Sat, 13 Jan 1996 23:28:56 -0500 (EST)
From: Sujal Patel <smpatel@wam.umd.edu>
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To: current@freebsd.org
Subject: ktrace causes vm_page_free: freeing busy page
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I think this was discussed a few months ago, but I'm pretty sure that 
this was fixed pretty quickly last time...  Well it's back :)

ktrace works for some things, but the following will panic the kernel in 
about 10-15 seconds (for me).  I'm running -current from a few days ago.

[smpatel:sl-015] [0:~]> cat panicme.c 
#include <stdio.h>
#include <fcntl.h>
main () {
        int f = open ("/etc/motd", O_RDONLY);
        while (1)
                lseek (f, 0, SEEK_SET);
}
[smpatel:sl-015] [0:~]> cc panicme.c 
[smpatel:sl-015] [0:~]> ktrace ./a.out

panic: vm_page_free: freeing busy page


Sujal