Bug 434760 - F-9 pv_ops: recursive locking warning during x86_32 DomU boot
Summary: F-9 pv_ops: recursive locking warning during x86_32 DomU boot
Keywords:
Status: CLOSED NOTABUG
Alias: None
Product: Fedora
Classification: Fedora
Component: kernel-xen-2.6
Version: rawhide
Hardware: All
OS: Linux
low
low
Target Milestone: ---
Assignee: Xen Maintainance List
QA Contact: Fedora Extras Quality Assurance
URL:
Whiteboard:
: 438707 (view as bug list)
Depends On:
Blocks: PvOpsTracker
TreeView+ depends on / blocked
 
Reported: 2008-02-25 10:54 UTC by Mark McLoughlin
Modified: 2008-03-25 17:28 UTC (History)
3 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed: 2008-03-25 17:28:12 UTC
Type: ---
Embargoed:


Attachments (Terms of Use)

Description Mark McLoughlin 2008-02-25 10:54:06 UTC
Seeing this with kernel-xen-2.6.24-23.7.pv_ops during DomU boot:

Red Hat nash version 6.0.29 starting
Mounting proc filesystem
Mounting sysfs filesystem
Creating /dev
Creating initial device nodes
Setting up hotplug.

=============================================
[ INFO: possible recursive locking detected ]
2.6.24-23.7.pv_ops.fc9xen #1
---------------------------------------------
init/1 is trying to acquire lock:
 (__pte_lockptr(new)){--..}, at: [<c10047c4>] pin_page+0x6c/0x12d

but task is already holding lock:
 (__pte_lockptr(new)){--..}, at: [<c10047c4>] pin_page+0x6c/0x12d

other info that might help us debug this:
4 locks held by init/1:
 #0:  (&mm->mmap_sem){----}, at: [<c10336c7>] copy_process+0xa7f/0x1306
 #1:  (&mm->mmap_sem/1){--..}, at: [<c10336dd>] copy_process+0xa95/0x1306
 #2:  (&mm->page_table_lock){--..}, at: [<c1004998>] xen_dup_mmap+0x11/0x24
 #3:  (__pte_lockptr(new)){--..}, at: [<c10047c4>] pin_page+0x6c/0x12d

stack backtrace:
Pid: 1, comm: init Not tainted 2.6.24-23.7.pv_ops.fc9xen #1
 [<c100bb70>] show_trace+0x1a/0x32
 [<c1255813>] _etext+0x6c/0x72
 [<c105290f>] __lock_acquire+0x8fe/0xc5b
 [<c1052ce7>] lock_acquire+0x7b/0x9e
 [<c12518a6>] _spin_lock+0x2e/0x58
 [<c10047c4>] pin_page+0x6c/0x12d
 [<c1003a94>] pgd_walk+0x119/0x162
 [<c10048c7>] xen_pgd_pin+0x42/0x102
 [<c10049a0>] xen_dup_mmap+0x19/0x24
 [<c10338af>] copy_process+0xc67/0x1306
 [<c1033f77>] do_fork+0x29/0x19e
 [<c100778b>] sys_clone+0x2f/0x31
 [<c100917a>] syscall_call+0x7/0xb
 =======================
Creating block device nodes.
Loading ehci-hcd module

Comment 1 Mark McLoughlin 2008-03-25 08:21:56 UTC
*** Bug 438707 has been marked as a duplicate of this bug. ***

Comment 2 Mark McLoughlin 2008-03-25 16:01:11 UTC
Note, this is only visible on x86_32

Comment 3 Mark McLoughlin 2008-03-25 17:28:12 UTC
Seems this is a harmless warning:

  http://lkml.org/lkml/2008/3/20/273

Hopefully upstream will figure out a way to avoid the warning, but there's no
point in keeping this bug open to track the issue.


Note You need to log in before you can comment on or make changes to this bug.