From owner-freebsd-hackers@FreeBSD.ORG  Sun Mar  4 09:39:42 2007
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Date: Sun, 4 Mar 2007 10:39:40 +0100
From: Divacky Roman <xdivac02@stud.fit.vutbr.cz>
To: hackers@freebsd.org
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Subject: inconsistency in using vn_fullpath1()
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hi

I noticed that kern___getcwd() calls vn_fullpath1() with Giant held like this:

	mtx_lock(&Giant);
	FILEDESC_LOCK(fdp);
        error = vn_fullpath1(td, fdp->fd_cdir, fdp->fd_rdir, tmpbuf,
            &bp, buflen);
        FILEDESC_UNLOCK(fdp);
        mtx_unlock(&Giant);

on the other hand vn_fullpath() calls it without Giant held like this:

	FILEDESC_LOCK(fdp);
        error = vn_fullpath1(td, vn, fdp->fd_rdir, buf, retbuf, MAXPATHLEN);
        FILEDESC_UNLOCK(fdp);

I dont see much difference in the callings so I wonder if holding Giant is necessary
when calling vn_fullpath1(). Because we either - do one unecessary locking operation
or unsufficiently lock it.

thnx for explaining to me and possibly fixing it.

roman