[Dovecot] Fault in dovecot 2.1.17

[Adrian Stoica]

The system hang, linux from scratch.
I have changed the live kernel from linux-2.6.35.4 to linux-2.6.32.61 , 
to see if the fault still occurs.
The kernel 2.6.35.4 was working fine with all version up to dovecot 
2.1.12 , from which i made update to 2.1.17.

dovecot -n
# 2.1.17: /usr/dovecot21/etc/dovecot/dovecot.conf
# OS: Linux 2.6.32.61 i686
auth_cache_negative_ttl = 1 secs
auth_cache_size = 2 M
auth_failure_delay = 4 secs
auth_mechanisms = plain login digest-md5 cram-md5
auth_worker_max_count = 100
base_dir = /var/run/dovecot/
default_client_limit = 4096
default_internal_user = vmail
default_login_user = nobody
default_process_limit = 256
deliver_log_format = mail delivery from=%f subject=%s msgid=%m: %$
dict {
   acl = mysql:/usr/dovecot21/etc/dovecot/dovecot-dict-sql.conf.ext
}
disable_plaintext_auth = no
first_valid_uid = 1
lda_mailbox_autocreate = yes
lda_mailbox_autosubscribe = yes
listen = *
mail_location = maildir:~/Maildir
mail_plugins = " quota acl trash notify mail_log"
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope 
encoded-character vacation subaddress comparator-i;ascii-numeric 
relational regex imap4flags copy include variables body enotify 
environment mailbox date ihave
namespace {
   hidden = no
   list = children
   location = maildir:%%h/Maildir:INDEX=~/Maildir/shared/%%u
   prefix = shared/%%u/
   separator = /
   subscriptions = no
   type = shared
}
namespace inbox {
   inbox = yes
   list = yes
   location =
   mailbox Drafts {
     special_use = \Drafts
   }
   mailbox Junk {
     special_use = \Junk
   }
   mailbox Sent {
     special_use = \Sent
   }
   mailbox "Sent Messages" {
     special_use = \Sent
   }
   mailbox Trash {
     special_use = \Trash
   }
   prefix =
   separator = /
   subscriptions = yes
   type = private
}
passdb {
   args = /usr/dovecot21/etc/dovecot/dovecot-sql.conf.ext
   driver = sql
}
plugin {
   acl = vfile
   acl_defaults_from_inbox = yes
   acl_shared_dict = proxy::acl
   autocreate = Trash
   autocreate2 = Drafts
   autocreate3 = Sent
   autosubscribe = Trash
   autosubscribe2 = Drafts
   autosubscribe3 = INBOX
   autosubscribe4 = Sent
   mail_log_events = delete mailbox_delete mailbox_rename
   mail_log_fields = box subject from msgid size
   quota = maildir:User quota
   quota_warning = storage=95%% quota-warning 95 %u
   quota_warning2 = storage=95%% quota-warning 90 %u
   quota_warning3 = storage=85%% quota-warning 85 %u
   sieve = ~/.dovecot.sieve
   sieve_dir = ~/sieve
   sieve_max_redirects = 10
   trash = /usr/dovecot21/etc/dovecot/dovecot-trash.conf.ext
}
postmaster_address = postmaster at dacris.net
protocols = imap
quota_full_tempfail = yes
rejection_subject = Rejected: %s: %r
service auth {
   unix_listener auth-client {
     mode = 0666
     user = vmail
   }
   unix_listener auth-userdb {
     mode = 0666
     user = vmail
   }
}
service dict {
   unix_listener dict {
     user = vmail
   }
}
service imap-login {
   process_min_avail = 4
}
service imap-postlogin {
   executable = script-login /bin/imap.sh
   unix_listener imap-postlogin {
     mode = 01232
   }
}
service imap {
   executable = imap imap-postlogin
   process_limit = 1024
   vsz_limit = 1 G
}
service quota-warning {
   executable = script /bin/quota_warning.sh
   unix_listener quota-warning {
     user = vmail
   }
   user = vmail
}
ssl_cert = </etc/ssl/certs/dovecot.pem
ssl_key = </etc/ssl/private/dovecot.pem
userdb {
   args = /usr/dovecot21/etc/dovecot/dovecot-sql.conf.ext
   driver = sql
}
protocol lda {
   mail_plugins = " quota acl trash notify mail_log sieve autocreate"
}
protocol imap {
   imap_client_workarounds = delay-newmail
   mail_max_userip_connections = 20
   mail_plugins = " quota acl trash notify mail_log imap_quota imap_acl"
}


Log from kernel:
Jul 11 10:14:01 mail kernel: BUG: Bad page map in process imap-login  
pte:c926b025 pmd:4597c067
Jul 11 10:14:01 mail kernel: page:c2f2ed60 count:1 mapcount:-1 
mapping:ec5a03a0 index:0x4ab
Jul 11 10:14:01 mail kernel: page flags: 
0x80020068(uptodate|lru|active|mappedtodisk)
Jul 11 10:14:01 mail kernel: addr:b73f4000 vm_flags:08000075 
anon_vma:(null) mapping:e289ec88 index:7b
Jul 11 10:14:01 mail kernel: vma->vm_ops->fault: filemap_fault+0x0/0x2fa
Jul 11 10:14:01 mail kernel: vma->vm_file->f_op->mmap: 
ext4_file_mmap+0x0/0x39
Jul 11 10:14:01 mail kernel: Pid: 22889, comm: imap-login Not tainted 
2.6.35.4 #2
Jul 11 10:14:01 mail kernel: Call Trace:
Jul 11 10:14:01 mail kernel:  [<c1078901>] ? print_bad_pte+0x13a/0x14b
Jul 11 10:14:01 mail kernel:  [<c107b206>] ? unmap_vmas+0x33b/0x62d
Jul 11 10:14:01 mail kernel:  [<c10272cc>] ? try_to_wake_up+0x206/0x210
Jul 11 10:14:01 mail kernel:  [<c107ccc7>] ? exit_mmap+0x8c/0x107
Jul 11 10:14:01 mail kernel:  [<c102976f>] ? mmput+0x1c/0x8c
Jul 11 10:14:01 mail kernel:  [<c102c850>] ? exit_mm+0xdc/0xe4
Jul 11 10:14:01 mail kernel:  [<c103da3c>] ? hrtimer_try_to_cancel+0x55/0x5b
Jul 11 10:14:01 mail kernel:  [<c104dd0d>] ? acct_collect+0x77/0x126
Jul 11 10:14:01 mail kernel:  [<c102dccb>] ? do_exit+0x1c8/0x5bc
Jul 11 10:14:01 mail kernel:  [<c109fd4d>] ? mntput_no_expire+0x15/0xad
Jul 11 10:14:01 mail kernel:  [<c102e119>] ? do_group_exit+0x5a/0x7d
Jul 11 10:14:01 mail kernel:  [<c102e14d>] ? sys_exit_group+0x11/0x14
Jul 11 10:14:01 mail kernel:  [<c100254c>] ? sysenter_do_call+0x12/0x22
Jul 11 10:14:01 mail kernel: Disabling lock debugging due to kernel taint
Jul 11 10:14:01 mail kernel: BUG: Bad page state in process imap-login  
pfn:c926b
Jul 11 10:14:01 mail kernel: page:c2f2ed60 count:0 mapcount:-1 
mapping:ec5a03a0 index:0x4ab
Jul 11 10:14:01 mail kernel: page flags: 0x80020008(uptodate|mappedtodisk)
Jul 11 10:14:01 mail kernel: Pid: 22889, comm: imap-login Tainted: G    
B       2.6.35.4 #2
Jul 11 10:14:01 mail kernel: Call Trace:
Jul 11 10:14:01 mail kernel:  [<c106c916>] ? bad_page+0x9c/0xae
Jul 11 10:14:01 mail kernel:  [<c106d4dc>] ? free_pages_prepare+0x55/0xc5
Jul 11 10:14:01 mail kernel:  [<c106d5f0>] ? free_hot_cold_page+0x20/0xef
Jul 11 10:14:01 mail kernel:  [<c106d739>] ? __pagevec_free+0x1a/0x21
Jul 11 10:14:01 mail kernel:  [<c106fb3a>] ? release_pages+0x165/0x16d
Jul 11 10:14:01 mail kernel:  [<c1083302>] ? 
free_pages_and_swap_cache+0x68/0x74
Jul 11 10:14:01 mail kernel:  [<c107b251>] ? unmap_vmas+0x386/0x62d
Jul 11 10:14:01 mail kernel:  [<c10272cc>] ? try_to_wake_up+0x206/0x210
Jul 11 10:14:01 mail kernel:  [<c107ccc7>] ? exit_mmap+0x8c/0x107
Jul 11 10:14:01 mail kernel:  [<c102976f>] ? mmput+0x1c/0x8c
Jul 11 10:14:01 mail kernel:  [<c102c850>] ? exit_mm+0xdc/0xe4
Jul 11 10:14:01 mail kernel:  [<c103da3c>] ? hrtimer_try_to_cancel+0x55/0x5b
Jul 11 10:14:01 mail kernel:  [<c104dd0d>] ? acct_collect+0x77/0x126
Jul 11 10:14:01 mail kernel:  [<c102dccb>] ? do_exit+0x1c8/0x5bc
Jul 11 10:14:01 mail kernel:  [<c109fd4d>] ? mntput_no_expire+0x15/0xad
Jul 11 10:14:01 mail kernel:  [<c102e119>] ? do_group_exit+0x5a/0x7d
Jul 11 10:14:01 mail kernel:  [<c102e14d>] ? sys_exit_group+0x11/0x14
Jul 11 10:14:01 mail kernel:  [<c100254c>] ? sysenter_do_call+0x12/0x22