panic: Trying sleep, but thread marked as sleeping prohibited

Hi,

I get the following panic now and then when trying to mount my external
usb drive.  The panic only occurs when the machine has been up for some
time.

FreeBSD serenity.local 7.0-CURRENT FreeBSD 7.0-CURRENT #8: Sun Feb 12
11:00:10 CET 2006     chris_at_serenity.local:/usr/obj/usr/src/sys/SERENITY
i386

panic: Trying sleep, but thread marked as sleeping prohibited
KDB: enter: panic
[thread pid 23 tid 100021 ]
Stopped at      kdb_enter+0x30: leave   
db> tr
Tracing pid 23 tid 100021 td 0xc344b820
kdb_enter(c07f8467,c086d160,c07fb33e,d564d8d4,100) at kdb_enter+0x30
panic(c07fb33e,1,c07fb2ba,111,2) at panic+0xd5
sleepq_add(cd7871c8,c0871320,c0811674,0,c0747a7d) at sleepq_add+0xb2
msleep(cd7871c8,c0871320,44,c0811674,0) at msleep+0x2a6
bwait(cd7871c8,44,c0811674,509,0) at bwait+0x60
swap_pager_putpages(c3dcb960,d564da10,1,1,d564d9c0) at swap_pager_putpages+0x497
default_pager_putpages(c3dcb960,d564da10,1,1,d564d9c0) at default_pager_putpages+0x2e
vm_pageout_flush(d564da10,1,1,60,c1900bd8) at vm_pageout_flush+0x172
vm_contig_launder_page(c1900b90,0,c081208a,1f6,ffffffff) at vm_contig_launder_page+0x239
vm_page_alloc_contig(10,0,0,ffffffff,1) at vm_page_alloc_contig+0x398
contigmalloc(10000,c0839c80,1,0,ffffffff) at contigmalloc+0xb5
bus_dmamem_alloc(c4fb4c80,c3fb2688,5,c3fb2684,ffffffff) at bus_dmamem_alloc+0xde
usb_block_allocmem(0,10000,1,c42a7f3c,c32e0448) at usb_block_allocmem+0x16e
usb_allocmem(c3649800,10000,0,c42a7f3c,d564db94) at usb_allocmem+0x57
ehci_allocm(c3649800,c42a7f3c,10000,c38e6400,d564dbc0) at ehci_allocm+0x27
usbd_transfer(c42a7f00,c4dccc80,c5218e00,d14c8000,10000) at usbd_transfer+0x61
umass_setup_transfer(c5218e00,c4dccc80,d14c8000,10000,4) at umass_setup_transfer+0x4f
umass_bbb_state(c365c100,c5218e00,0,0,0) at umass_bbb_state+0xeb
usb_transfer_complete(c365c100,1f,c39cf180) at usb_transfer_complete+0x193
ehci_idone(c365c100,c365c170,0,d564dc6c,c05211b2) at ehci_idone+0x137
ehci_check_intr(c3649800,c365c100,c05c0d55,26e,c3649800) at ehci_check_intr+0x8f
ehci_softintr(c3649800,d564dc9c,c0520f30,c3649800,298) at ehci_softintr+0x32
usb_schedsoftintr(c3649800,298,c07f52d6,d564dcb0,c365d080) at usb_schedsoftintr+0x12
ehci_intr1(c3649800,c365d080,c32e2580,d564dcd8,c058ce48) at ehci_intr1+0xc0
ehci_intr(c3649800,0,c07f52d6,295,1) at ehci_intr+0x8f
ithread_execute_handlers(c344a000,c32e2580,c07f52d6,2f9,c344b820) at ithread_execute_handlers+0x128
ithread_loop(c35f3e80,d564dd38,c07f50c8,31a,0) at ithread_loop+0x83
fork_exit(c058cf50,c35f3e80,d564dd38) at fork_exit+0xc3
fork_trampoline() at fork_trampoline+0x8
--- trap 0x1, eip = 0, esp = 0xd564dd6c, ebp = 0 ---


- Christian

-- 
Christian Brueffer	chris_at_unixpages.org	brueffer_at_FreeBSD.org
GPG Key:	 http://people.freebsd.org/~brueffer/brueffer.key.asc
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