kern/165475: commit references a PR

[dfilter service]

The following reply was made to PR kern/165475; it has been noted by GNATS.

From: dfilter at FreeBSD.ORG (dfilter service)
To: bug-followup at FreeBSD.org
Cc:  
Subject: Re: kern/165475: commit references a PR
Date: Sun, 26 Feb 2012 06:05:00 +0000 (UTC)

 Author: adrian
 Date: Sun Feb 26 06:04:44 2012
 New Revision: 232170
 URL: http://svn.freebsd.org/changeset/base/232170
 
 Log:
   Add in some debugging code to check whether the current rate table has
   been bait-and-switched from the rate control code.
   
   This will avoid the panic that I saw and will avoid sending invalid rates
   (eg 11a/11g OFDM rates when in 11b, on 11b-only NICs (AR5211)) where the
   rate table is not "big".
   
   It also will point out situations where this occurs for the 11n NICs
   which will have sufficiently large rate tables that "invalid rix" doesn't
   occur.
   
   I'll try to follow this up with a commit that adds a current operating mode
   check. The "rix" is only relevant to the current operating mode and rate
   table.
   
   PR:	kern/165475
 
 Modified:
   head/sys/dev/ath/ath_rate/sample/sample.c
   head/sys/dev/ath/ath_rate/sample/sample.h
 
 Modified: head/sys/dev/ath/ath_rate/sample/sample.c
 ==============================================================================
 --- head/sys/dev/ath/ath_rate/sample/sample.c	Sun Feb 26 02:24:40 2012	(r232169)
 +++ head/sys/dev/ath/ath_rate/sample/sample.c	Sun Feb 26 06:04:44 2012	(r232170)
 @@ -495,6 +495,14 @@ ath_rate_findrate(struct ath_softc *sc, 
  
  	ath_rate_update_static_rix(sc, &an->an_node);
  
 +	if (sn->currates != sc->sc_currates) {
 +		device_printf(sc->sc_dev, "%s: currates != sc_currates!\n",
 +		    __func__);
 +		rix = 0;
 +		*try0 = ATH_TXMAXTRY;
 +		goto done;
 +	}
 +
  	if (sn->static_rix != -1) {
  		rix = sn->static_rix;
  		*try0 = ATH_TXMAXTRY;
 @@ -621,6 +629,20 @@ ath_rate_findrate(struct ath_softc *sc, 
  	}
  	*try0 = mrr ? sn->sched[rix].t0 : ATH_TXMAXTRY;
  done:
 +
 +	/*
 +	 * This bug totally sucks and should be fixed.
 +	 *
 +	 * For now though, let's not panic, so we can start to figure
 +	 * out how to better reproduce it.
 +	 */
 +	if (rix < 0 || rix >= rt->rateCount) {
 +		printf("%s: ERROR: rix %d out of bounds (rateCount=%d)\n",
 +		    __func__,
 +		    rix,
 +		    rt->rateCount);
 +		    rix = 0;	/* XXX just default for now */
 +	}
  	KASSERT(rix >= 0 && rix < rt->rateCount, ("rix is %d", rix));
  
  	*rix0 = rix;
 @@ -1073,6 +1095,8 @@ ath_rate_ctl_reset(struct ath_softc *sc,
          sn->static_rix = -1;
  	ath_rate_update_static_rix(sc, ni);
  
 +	sn->currates = sc->sc_currates;
 +
  	/*
  	 * Construct a bitmask of usable rates.  This has all
  	 * negotiated rates minus those marked by the hal as
 
 Modified: head/sys/dev/ath/ath_rate/sample/sample.h
 ==============================================================================
 --- head/sys/dev/ath/ath_rate/sample/sample.h	Sun Feb 26 02:24:40 2012	(r232169)
 +++ head/sys/dev/ath/ath_rate/sample/sample.h	Sun Feb 26 06:04:44 2012	(r232170)
 @@ -86,6 +86,8 @@ struct sample_node {
  	uint32_t ratemask;		/* bit mask of valid rate indices */
  	const struct txschedule *sched;	/* tx schedule table */
  
 +	const HAL_RATE_TABLE *currates;
 +
  	struct rate_stats stats[NUM_PACKET_SIZE_BINS][SAMPLE_MAXRATES];
  	int last_sample_rix[NUM_PACKET_SIZE_BINS];
  
 _______________________________________________
 svn-src-all at freebsd.org mailing list
 http://lists.freebsd.org/mailman/listinfo/svn-src-all
 To unsubscribe, send any mail to "svn-src-all-unsubscribe at freebsd.org"