kern/72478: ata: dd destroy FreeBSD raid header

[Daisuke Takahashi]

>Number:         72478
>Category:       kern
>Synopsis:       ata: dd destroy FreeBSD raid header
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sun Oct 10 10:30:20 GMT 2004
>Closed-Date:
>Last-Modified:
>Originator:     Daisuke Takahashi
>Release:        FreeBSD 5.3-BETA7
>Organization:
personal
>Environment:
FreeBSD mika-l.lodaldomain 5.3-BETA7 FreeBSD 5.3-BETA7 #1: Sun Oct 10 17:42:06 JST 2004     root at mika-l.lodaldomain:/usr/src/sys/i386/compile/GENERIC  i386

- - -
Oct 10 16:33:58 mika-l kernel: ad1: 102MB <VMware Virtual IDE Hard Drive/00000001> [208/16/63] at ata0-slave UDMA33
Oct 10 16:33:58 mika-l kernel: ad3: 204MB <VMware Virtual IDE Hard Drive/00000001> [416/16/63] at ata1-slave UDMA33

>Description:
I created ar0 as follow.

  # atacontrol create SPAN ad1 ad3

syslog as follow
 Oct 10 16:36:31 mika-l kernel: ar0: 204MB <ATA SPAN array> [26/255/63] status: READY subdisks:
 Oct 10 16:36:31 mika-l kernel: disk0 READY on ad1 at ata0-slave
 Oct 10 16:36:31 mika-l kernel: disk1 READY on ad3 at ata1-slave


But when I use entire space of ar0, ar0 reports "ar0: ERROR - array broken" at next boot time.

 Oct 10 16:39:41 mika-l kernel: ar0: ERROR - array broken
 Oct 10 16:39:41 mika-l kernel: ar0: 204MB <ATA SPAN array> [26/255/63] status: BROKEN subdisks:
 Oct 10 16:39:41 mika-l kernel: disk0 DOWN no device found for this disk
 Oct 10 16:39:41 mika-l kernel: disk1 READY on ad3 at ata1-slave

>How-To-Repeat:
1. create ar0 as SPAN disk 
   # atacontrol create SPAN ad1 ad3

2. write '0' to entire ar0
   # dd if=/dev/zero of=/dev/ar0 bs=64k

3. reboot
>Fix:

--- ata-raid.c.orig     Tue Jan 27 14:53:19 2004
+++ ata-raid.c  Thu Sep 30 15:55:23 2004
@@ -556,9 +560,9 @@
        switch (rdp->flags & (AR_F_RAID0 | AR_F_RAID1 | AR_F_SPAN)) {
        case AR_F_SPAN:
            lba = blkno;
-           while (lba >= AD_SOFTC(rdp->disks[drv])->total_secs-rdp->reserved)
-               lba -= AD_SOFTC(rdp->disks[drv++])->total_secs-rdp->reserved;
-           chunk = min(AD_SOFTC(rdp->disks[drv])->total_secs-rdp->reserved-lba,
+           while (lba >= rdp->disks[drv].disk_sectors)
+               lba -= rdp->disks[drv++].disk_sectors;
+           chunk = min(rdp->disks[drv].disk_sectors-lba,
                        count);
            break;

@@ -670,9 +674,9 @@
        switch (rdp->flags & (AR_F_RAID0 | AR_F_RAID1 | AR_F_SPAN)) {
        case AR_F_SPAN:
            lba = blkno;
-           while (lba >= AD_SOFTC(rdp->disks[drv])->total_secs-rdp->reserved)
-               lba -= AD_SOFTC(rdp->disks[drv++])->total_secs-rdp->reserved;
-           chunk = min(AD_SOFTC(rdp->disks[drv])->total_secs-rdp->reserved-lba,
+           while (lba >= rdp->disks[drv].disk_sectors)
+               lba -= rdp->disks[drv++].disk_sectors;
+           chunk = min(rdp->disks[drv].disk_sectors-lba,
                        count);
            break;



>Release-Note:
>Audit-Trail:
>Unformatted: