Red Hat Bugzilla – Bug 434760
F-9 pv_ops: recursive locking warning during x86_32 DomU boot
Last modified: 2008-03-25 13:28:12 EDT
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
*** Bug 438707 has been marked as a duplicate of this bug. ***
Note, this is only visible on x86_32
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.