>Number:         24745
>Category:       kern
>Synopsis:       kernel prompts for a root device when using md_root
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Mar 11 14:03:00 UTC 2004
>Closed-Date:
>Last-Modified:
>Originator:     Jared Momose
>Release:        NetBSD-current
>Organization:
none
>Environment:
NetBSD kiwi.ams.apc.com 1.6ZF NetBSD 1.6ZF (CC405EP) #204: Thu Mar 11 03:47:22 EST 2004  jmomose@jaredlap.rrg.ams.apc.com:/usr/src-13NOV03/sys/arch/evbppc/compile/CC405EP evbppc
>Description:
When md is used as the root device, the kernel always prompts the console user to specify a root device. This is a bit annoying as it prevents the kernel from booting completely without user interaction.

This problem occurs because the RB_ASKNAME flag for boothowto is set when the function finddevice:kern_subr.c fails to find the correct device.
>How-To-Repeat:
1. Compile a kernel with space/configured for md as root
2. mdsetimage a ramdisk.fs into the kernel
3. Boot and observe that the kernel prompts for a root device

>Fix:
My solution was to add a small section of code in kern_subr.c that, if the kernel option MEMORY_DISK_IS_ROOT is set, will allow finddevice:kern_subr.c to search the list of md devices (fakemdrootdev) for a match before it searches the list of auto detected devices (alldevs). This change is nearly identitical to that made for RAID. See my patch below:


-------------------- CUT HERE - patch-md-root ---------------------
Index: src/sys/kern/kern_subr.c
===================================================================
RCS file: /cvsroot/src/sys/kern/kern_subr.c,v
retrieving revision 1.107
diff -u -r1.107 kern_subr.c
--- src/sys/kern/kern_subr.c	2003/10/31 03:28:14	1.107
+++ src/sys/kern/kern_subr.c	2003/12/19 20:27:46
@@ -716,6 +716,10 @@
 static struct device fakemdrootdev[NMD];
 #endif
 
+#ifdef MEMORY_DISK_IS_ROOT
+#define BOOT_FROM_MEMORY_HOOKS 1
+#endif
+
 #include "raid.h"
 #if NRAID == 1
 #define BOOT_FROM_RAID_HOOKS 1 
@@ -1061,16 +1065,30 @@
 	const char *name;
 {
 	struct device *dv;
+#ifdef BOOT_FROM_MEMORY_HOOKS
+	int i;
+#endif /* BOOT_FROM_MEMORY_HOOKS */
 #ifdef BOOT_FROM_RAID_HOOKS
 	int j;
+#endif /* BOOT_FROM_RAID_HOOKS */
 
+#ifdef BOOT_FROM_RAID_HOOKS
 	for (j = 0; j < numraid; j++) {
 		if (strcmp(name, raidrootdev[j].dv_xname) == 0) {
 			dv = &raidrootdev[j];
 			return (dv);
 		}
 	}
-#endif
+#endif /* BOOT_FROM_RAID_HOOKS */
+
+#ifdef BOOT_FROM_MEMORY_HOOKS
+	for (i = 0; i < NMD; i++) {
+		if (strcmp(name, fakemdrootdev[i].dv_xname) == 0) {
+			dv = &fakemdrootdev[i];
+			return (dv);
+		}
+	}
+#endif /* BOOT_FROM_MEMORY_HOOKS */
 
 	for (dv = TAILQ_FIRST(&alldevs); dv != NULL;
 	    dv = TAILQ_NEXT(dv, dv_list))
--------------------------- END ---------------------------------


>Release-Note:
>Audit-Trail:
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