[Crash-utility] Fwd: [PATCH] crash: unwind with LKCD_KERNTYPES

[Dave Anderson]

----- Forwarded Message -----
From: "Cliff Wickman" <cpw at sgi.com>
To: "Dave Anderson" <anderson at redhat.com>
Sent: Friday, January 23, 2009 10:30:49 AM GMT -05:00 US/Canada Eastern
Subject: Re: [PATCH] crash: unwind with LKCD_KERNTYPES

Hi Dave,

On Fri, Jan 23, 2009 at 10:09:30AM -0500, Dave Anderson wrote:
> 
> ----- "Cliff Wickman" <cpw at sgi.com> wrote:
> 
> > This patch enables stack unwind (on ia64) when using a kerntypes
> > file for a namelist.
> > 
> > When using a kerntypes file, we have just the address of variable unw
> > and the definition of an unw structure.
> > 
> > As you can see, I didn't change the indentation of the normal code.
> 
> Nicely segregated.  But instead of leaving the indentation screwed up,
> I just inserted a "goto verify" at the bottom of your if statement and
> put the label at the proper location.
> 
> > Simple to do, but I didn't want to clutter this patch for a first
> > pass.
> 
> With that in place, should I just take the patch for the next release,
> or did you have something else you want to add?

Sounds good.  I have nothing more to add.  Thanks.

-Cliff
> 
> Dave
>   
> 
> > 
> > ---
> >  unwind.c |   34 ++++++++++++++++++++++++++++++++++
> >  1 file changed, 34 insertions(+)
> > 
> > Index: crash-4.0-7.6.ia64/unwind.c
> > ===================================================================
> > --- crash-4.0-7.6.ia64.orig/unwind.c
> > +++ crash-4.0-7.6.ia64/unwind.c
> > @@ -1395,10 +1395,43 @@ unwind_init_v2(void)
> >  unwind_init_v3(void)
> >  #endif
> >  {
> > +	int len;
> >  	struct gnu_request request, *req;
> >  
> >  	req = &request;
> >  
> > +	if (LKCD_KERNTYPES()) {
> > +		if ((len = STRUCT_SIZE("unw")) == 0) {
> > +			error(WARNING,
> > +			"cannot determine unw.tables offset; no struct unw\n");
> > +			machdep->flags |= UNW_OUT_OF_SYNC;
> > +			return;
> > +		}
> > +		machdep->machspec->unw_tables_offset =
> > +			MEMBER_OFFSET("unw", "tables");
> > +		if (MEMBER_EXISTS("unw", "r0"))
> > +			machdep->flags |= UNW_R0;
> > +		/*
> > +		 * no verification of save_order, sw_off, preg_index as
> > +		 * we're purely depending on the structure definition.
> > +		 */
> > +        	if (MEMBER_EXISTS("unw", "pt_regs_offsets")) {
> > +			machdep->machspec->unw_pt_regs_offsets =
> > +				MEMBER_OFFSET("unw", "pt_regs_offsets") -
> > +				machdep->machspec->unw_tables_offset;
> > +			machdep->machspec->unw_kernel_table_offset =
> > +				MEMBER_OFFSET("unw", "kernel_table") -
> > +				machdep->machspec->unw_tables_offset;
> > +			machdep->flags |= UNW_PTREGS;
> > +		}
> > +		if (!load_unw_table(CLEAR_SCRIPT_CACHE)) {
> > +        		error(WARNING,
> > +				"unwind_init: cannot read kernel unw table\n");
> > +                	machdep->flags |= UNW_OUT_OF_SYNC;
> > +		}
> > +		machdep->machspec->unw = (void *)&unw;
> > +		/* fall to common structure size verifications */
> > +	} else {
> >          if (get_symbol_type("unw", "tables", req) == TYPE_CODE_UNDEF)
> > {
> >  		/*
> >  		 *  KLUDGE ALERT:
> > @@ -1449,6 +1482,7 @@ unwind_init_v3(void)
> >  
> >  		machdep->machspec->unw = (void *)&unw;
> >  	}
> > +	}
> >  
> >  	verify_common_struct("unw_frame_info", sizeof(struct
> > unw_frame_info));
> >  	verify_common_struct("unw_table", sizeof(struct unw_table));

-- 
Cliff Wickman
Silicon Graphics, Inc.
cpw at sgi.com
(651) 683-3824