Freeze with 10.0 and VirtualBox {4.1.4|4.1.6|4.1.51r38464}

Andriy Gapon avg at
Sun Nov 27 08:41:31 UTC 2011

on 27/11/2011 03:36 Michael Butler said the following:
> On 11/26/11 11:33, Gleb Kurtsou wrote:
>> On (26/11/2011 14:44), Andriy Gapon wrote:
>>> vm_phys_alloc_contig implementation has been recently changed and now it seems
>>> to require that vm_page_queue_free_mtx is held.
>> Using new vm_page_alloc_contig() may be a better option here. Can't help
>> with patch, stuck with pre Nov 15 CURRENT myself.
> If I understand the change in locking semantics (post SVN r227568?), a good
> number of chunks of src/VBox/Runtime/r0drv/freebsd/memobj-r0drv-freebsd.c need
> updating to follow this :-(.
> It is now insufficient to hold only the queue lock when calling vm_page_unwire
> or vm_page_free (and maybe others). The page itself must now also be locked,

Not "also", but instead.  And only for managed pages.  For unmanaged pages a
caller doesn't have to acquire anything.
The relevant change in head has happened much much earlier than r227568.

And this is a totally different issue from the vm_phys_alloc_contig issue.
Let's not mix them.

Andriy Gapon

More information about the freebsd-current mailing list