Re: kern/48849: root mirror raid fails on shutdown

[Patrick Welche <prlw1%cam.ac.uk@localhost>]

The following reply was made to PR kern/48849; it has been noted by GNATS.

From: Patrick Welche <prlw1%cam.ac.uk@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
        netbsd-bugs%netbsd.org@localhost
Subject: Re: kern/48849: root mirror raid fails on shutdown
Date: Fri, 30 May 2014 19:33:11 +0100

 With your patch, I no longer see any forceful unmounts, however the
 computer doesn't shut down either. I sprinkled a few printfs in dounmount(),
 and see:
 
 Entering dounmount /var (/dev/raid7e)...
 VFS_SYNC(/var) = 0
 VFS_UNMOUNT(/var) = 0 
 called vfs_hooks_unmount(/var)
 Successfully exiting dounmount /var (/dev/raid7e)...
 unmounting 0xfffffe811e883008 / (/dev/raid7a)...
 Entering dounmount / (/dev/raid7a)...
 VFS_SYNC(/) = 0
 VFS_UNMOUNT(/) = 16 
 unmounting 0xfffffe811e883008 / (/dev/raid7a)...
 Entering dounmount / (/dev/raid7a)...
 VFS_SYNC(/) = 0
 VFS_UNMOUNT(/) = 16 
 cd0: detached
 atapibus0: detached
 [other detached snipped]
 raid6: detached
 raid5: detached
 raid5: detached
 -- and this is where we hang
 
 Note there is no "exiting dounmount" for raid7a
 
 Breaking into ddb at this point
 
 Stopped in pid 0.5 (system) at  netbsd:breakpoint+0x5:  leave
 db{0}> bt
 breakpoint() at netbsd:breakpoint+0x5
 comintr() at netbsd:comintr+0x529
 Xintr_ioapic_edge1() at netbsd:Xintr_ioapic_edge1+0xea
 --- interrupt ---
 _kernel_lock() at netbsd:_kernel_lock+0x165
 intr_biglock_wrapper() at netbsd:intr_biglock_wrapper+0x12
 Xintr_ioapic_level3() at netbsd:Xintr_ioapic_level3+0xf2
 --- interrupt ---
 _kernel_lock() at netbsd:_kernel_lock+0x165
 frag6_fasttimo() at netbsd:frag6_fasttimo+0x1a
 pffasttimo() at netbsd:pffasttimo+0x31
 callout_softclock() at netbsd:callout_softclock+0x1d0
 softint_dispatch() at netbsd:softint_dispatch+0xd3
 DDB lost frame for netbsd:Xsoftintr+0x4f, trying 0xfffffe80cd845ff0
 Xsoftintr() at netbsd:Xsoftintr+0x4f
 --- interrupt ---
 0: