panic: reassignbuf: dup lblk vp 0xffffffe0136df000 bp 0xffffffe00df730b0

[Antonio Huete Jimenez]

Hi Yonetani,

There was a correction on February 3th specifically for x86_64. I
don't know if that's related to the panic somehow or not, but
definitely for the rebalance issue you're having.

http://gitweb.dragonflybsd.org/dragonfly.git/commit/7a3eee88d3ffab887e1b2d812672f20071d39947

Cheers,
Antonio Huete

2011/2/9 YONETANI Tomokazu <y0n3t4n1 at gmail.com>:
> Hello.
> Caught this panic this morning during `hammer cleanup' on a Atom D510
> based system with 4G bytes of RAM installed and running x86_64 kernel.
> It was running pbulk at the same time.  The kernel was built from source
> s of 8d2576868.  The `insufficient buffers to rebalance the tree' warnings
> have been observed before the system panicked.  The global variable nbuf
> (which holds the value for vfs.nbuf sysctl node) contains 1475 in the kgdb
> session, which is much lower than the value seen on other systems running
> 32-bit kernel.
>
>                                :
>  Feb  9 05:05:09 atom64 kernel: hammer: System has insufficient buffers to rebalance the tree.  nbuf < 3969
>  Feb  9 05:19:01 atom64 kernel: hammer: System has insufficient buffers to rebalance the tree.  nbuf < 3969
>  Feb  9 05:27:23 atom64 syslogd: kernel boot file is /boot/kernel/kernel
>  Feb  9 05:27:23 atom64 kernel: panic: reassignbuf: dup lblk vp 0xffffffe0136df000 bp 0xffffffe00df730b0
>
> And the backtrace follows:
>
> #4  0xffffffff802a9c1e in panic (
>    fmt=0xffffffff80530140 "reassignbuf: dup lblk vp %p bp %p")
>    at /usr/src/sys/kern/kern_shutdown.c:799
> #5  0xffffffff8031262f in reassignbuf (bp=0xffffffe00df730b0)
>    at /usr/src/sys/kern/vfs_subr.c:1046
> #6  0xffffffff802fa526 in bundirty (bp=0xffffffe00df730b0)
>    at /usr/src/sys/kern/vfs_bio.c:1247
> #7  0xffffffff802fe705 in bawrite (bp=0xffffffe00df730b0)
>    at /usr/src/sys/kern/vfs_bio.c:1025
> #8  0xffffffff802fe98a in vfs_bio_awrite (bp=0xffffffe00df730b0)
>    at /usr/src/sys/kern/vfs_bio.c:1937
> #9  0xffffffff802fedae in flushbufqueues (q=BQUEUE_DIRTY)
>    at /usr/src/sys/kern/vfs_bio.c:2694
> #10 0xffffffff802ff041 in buf_daemon () at /usr/src/sys/kern/vfs_bio.c:2525
> #11 0xffffffff8029961e in suspend_kproc (td=0x0, timo=0)
>    at /usr/src/sys/kern/kern_kthread.c:189
> Backtrace stopped: previous frame inner to this frame (corrupt stack?)
> (kgdb) fr 5
> #5  0xffffffff8031262f in reassignbuf (bp=0xffffffe00df730b0)
>    at /usr/src/sys/kern/vfs_subr.c:1046
> 1046                                    panic("reassignbuf: dup lblk vp %p bp %p",
> (kgdb) l
> 1041                            buf_rb_tree_RB_REMOVE(&vp->v_rbdirty_tree, bp);
> 1042                            bp->b_flags &= ~B_VNDIRTY;
> 1043                    }
> 1044                    if ((bp->b_flags & B_VNCLEAN) == 0) {
> 1045                            if (buf_rb_tree_RB_INSERT(&vp->v_rbclean_tree, bp)) {
> 1046                                    panic("reassignbuf: dup lblk vp %p bp %p",
> 1047                                          vp, bp);
> 1048                            }
> 1049                            bp->b_flags |= B_VNCLEAN;
> 1050                    }
> (kgdb)
>
> Best Regards,
> YONETANI Tomokazu.
>