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Date: Wed, 17 Aug 2005 15:44:59 +0300
From: Giorgos Keramidas <keramida@freebsd.org>
To: Poul-Henning Kamp <phk@haven.freebsd.dk>
Message-ID: <20050817124459.GF1084@flame.pc>
References: <17182.1124270021@phk.freebsd.dk>
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Cc: current@freebsd.org
Subject: Re: Giant around fdfree() in exit1() ?
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On 2005-08-17 11:13, Poul-Henning Kamp <phk@haven.freebsd.dk> wrote:
>
> I'm seeing Giant held in a MNTK_MPSAFE devfs->close without this patch,
> any insight/comments ?

fdfree() releases POSIX locks the descriptor has.  Is it ok to call
VOP_ADVLOCK(..., F_UNLCK, ...) and free() without holding Giant?

> Index: kern/kern_exit.c
> ===================================================================
> RCS file: /home/ncvs/src/sys/kern/kern_exit.c,v
> retrieving revision 1.264
> diff -u -r1.264 kern_exit.c
> --- kern/kern_exit.c	18 Jul 2005 20:08:14 -0000	1.264
> +++ kern/kern_exit.c	17 Aug 2005 08:42:38 -0000
> @@ -229,13 +229,13 @@
>  	 */
>  	mtx_lock(&Giant);	/* XXX: not sure if needed */
>  	funsetownlst(&p->p_sigiolst);
> +	mtx_unlock(&Giant);	
>  
>  	/*
>  	 * Close open files and release open-file table.
>  	 * This may block!
>  	 */
>  	fdfree(td);
> -	mtx_unlock(&Giant);