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Matt Macy 71d48dbda3 MFV/ZoL: Fix PANIC: metaslab_free_dva(): bad DVA X:Y:Z
commit 81edd3e834
Author: Peng <peng.hse@xtaotech.com>
Date:   Wed Jun 8 15:22:07 2016 +0800

    Fix PANIC: metaslab_free_dva(): bad DVA X:Y:Z

    The following scenario can result in garbage in the dn_spill field.
    The db->db_blkptr must be set to NULL when DNODE_FLAG_SPILL_BLKPTR
    is clear to ensure the dn_spill field is cleared.

    Current txg = A.
    * A new spill buffer is created. Its dbuf is initialized with
      db_blkptr = NULL and it's dirtied.

    Current txg = B.
    * The spill buffer is modified. It's marked as dirty in this txg.
    * Additional changes make the spill buffer unnecessary because the
      xattr fits into the bonus buffer, so it's removed. The dbuf is
      undirtied in this txg, but it's still referenced and cannot be
      destroyed.

    Current txg = C.
    * Starts syncing of txg A
    * dbuf_sync_leaf() is called for the spill buffer. Since db_blkptr
      is NULL, dbuf_check_blkptr() is called.
    * The dbuf starts being written and it reaches the ready state
      (not done yet).
    * A new change makes the spill buffer necessary again.
      sa_build_layouts() ends up calling dbuf_find() to locate the
      dbuf.  It finds the old dbuf because it has not been destroyed yet
      (it will be destroyed when the previous write is done and there
      are no more references). The old dbuf has db_blkptr != NULL.
    * txg A write is complete and the dbuf released. However it's still
      referenced, so it's not destroyed.

    Current txg = D.
    * Starts syncing of txg B
    * dbuf_sync_leaf() is called for the bonus buffer. Its contents are
      directly copied into the dnode, overwriting the blkptr area because,
      in txg B, the bonus buffer was big enough to hold the entire xattr.
    * At this point, the db_blkptr of the spill buffer used in txg C
      gets corrupted.

    Signed-off-by: Peng <peng.hse@xtaotech.com>
    Signed-off-by: Tim Chase <tim@chase2k.com>
    Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
    Closes #3937
2018-08-12 01:17:32 +00:00
bin ls(1): Enable colors with COLORTERM is set in the environment 2018-08-08 21:51:19 +00:00
cddl MFV/ZoL: Implement large_dnode pool feature 2018-08-12 00:45:53 +00:00
contrib Merge libbe(3)/bectl(8) from projects/bectl into head 2018-08-11 23:50:09 +00:00
crypto Merge upstream patch to unbreak tunnel forwarding. 2018-05-16 14:04:39 +00:00
etc Move all NTP related files to usr.sbin/ntp/ntpd. 2018-08-11 17:42:42 +00:00
gnu Update libstdc++ configuration. 2018-07-16 18:53:28 +00:00
include Bring in timespce_get form NetBSD. 2018-08-10 15:16:30 +00:00
kerberos5 krb5-config build: Remove gratuitous escaping 2018-08-12 00:06:21 +00:00
lib getopt_long(3): Document behavior of leading characters in optstring 2018-08-12 00:08:14 +00:00
libexec Remove pointless comment. 2018-08-03 10:59:05 +00:00
release Invoke the growfs rc script for each boot on GCE. 2018-08-09 23:43:10 +00:00
rescue
sbin bectl(8): Use strcmp, rather than trying to directly compare 2018-08-12 00:09:52 +00:00
secure Upgrade to OpenSSH 7.7p1. 2018-05-11 13:22:43 +00:00
share Merge libbe(3)/bectl(8) from projects/bectl into head 2018-08-11 23:50:09 +00:00
stand libi386: Fix typo in pxe.h 2018-08-09 03:45:47 +00:00
sys MFV/ZoL: Fix PANIC: metaslab_free_dva(): bad DVA X:Y:Z 2018-08-12 01:17:32 +00:00
targets Remove special cases for armeb in the build. 2018-07-17 23:23:54 +00:00
tests pf tests: Basic test for 'set skip in $groupname' 2018-08-11 16:41:07 +00:00
tools Make distribution now happens from top of source tree. 2018-08-10 06:28:25 +00:00
usr.bin fix top after arc accounting change 2018-08-11 22:11:12 +00:00
usr.sbin Move all NTP related files to usr.sbin/ntp/ntpd. 2018-08-11 17:42:42 +00:00
.arcconfig
.arclint
.gitattributes Remove spuriously added svn properties 2018-08-02 18:37:02 +00:00
.gitignore Ignore _.universe-toolchain file. 2018-07-01 13:50:37 +00:00
COPYRIGHT Remove 'All Rights Reserved' from the collection copyright and templates. 2018-05-09 02:02:49 +00:00
LOCKS LOCKS: update current locks 2018-06-09 03:08:04 +00:00
MAINTAINERS Add pointer to freebsd-numerics for libm. 2018-07-16 15:29:32 +00:00
Makefile As discussed several times on freebsd-arch, start to decommission armeb. 2018-07-17 23:23:34 +00:00
Makefile.inc1 libbe(3)/bectl(8): More SYSROOT/GCC build fixes 2018-08-11 22:45:39 +00:00
Makefile.libcompat Install the 32-bit compat sanitizer libraries. 2018-08-03 18:52:51 +00:00
Makefile.sys.inc
ObsoleteFiles.inc Add a few forgotten files to ObsoleteFiles.inc: 2018-07-25 17:14:05 +00:00
README README: add generic notes about GENERIC and NOTES 2018-06-17 19:44:24 +00:00
README.md README: add generic notes about GENERIC and NOTES 2018-06-17 19:44:24 +00:00
UPDATING Switch the default pager for most commands to less 2018-08-08 19:24:20 +00:00

FreeBSD Source:

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