K 10
svn:author
V 6
emaste
K 8
svn:date
V 27
2007-02-20T18:10:13.000000Z
K 7
svn:log
V 459
Avoid writing uninitialized stack data into a thread's MMX/SSE state by
first getting the current state with td_thr_getxmmregs_p.  Without this,
debugging a threaded app that uses libthr resulted in kernel panics or
spurious SIGFPEs for me.

(As of revision 1.6, sys/i386/i386/ptrace_machdep.c masks off the
reserved bits in the mxcsr register, which prevents the kernel panics.)

Architectures without PT_GETXMMREGS are not affected.

MFC after:      1 week

END