Why are %fs and %gs set back to default (_udata_sel) when posting

I am planning on using %fs for TSD/KSD and want it to be valid
in signal handlers.

A test program is at:


Compile it with -DDEBUG on an unpatched kernel to show more

This following seems to fix it.  Any reason it would cause

Index: machdep.c
RCS file: /opt/FreeBSD/cvs/src/sys/i386/i386/machdep.c,v
retrieving revision 1.447
diff -u -r1.447 machdep.c
--- machdep.c   2001/04/27 19:28:19     1.447
+++ machdep.c   2001/05/01 22:20:52
@@ -745,8 +745,6 @@
        regs->tf_cs = _ucodesel;
        regs->tf_ds = _udatasel;
        regs->tf_es = _udatasel;
-       regs->tf_fs = _udatasel;
-       load_gs(_udatasel);
        regs->tf_ss = _udatasel;

Dan Eischen

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