On Thu, Aug 06, 2015 at 03:35:59PM +0200, Paolo Bonzini wrote:
> This is the first step towards having fine-grained critical sections in
> dataplane threads, which resolves lock ordering problems between
> address_space_* functions (which need the BQL when doing MMIO, even
> after we complete RCU-based dispatch) and the AioContext.
>
> Because AioContext does not use contention callbacks anymore, the
> unit test has to be changed.
>
> Previously applied as a0710f7995f914e3044e5899bd8ff6c43c62f916 and
> then reverted.
commit da5e1de95bb235330d7724316e7a29239d1359d5
Author: Stefan Hajnoczi <stefa...@redhat.com>
Date: Wed Jun 3 10:15:33 2015 +0100
Revert "iothread: release iothread around aio_poll"
This reverts commit a0710f7995f914e3044e5899bd8ff6c43c62f916.
In qemu-devel email message <556dbf87.2020...@de.ibm.com>, Christian
Borntraeger writes:
Having many guests all with a kernel/ramdisk (via -kernel) and
several null block devices will result in hangs. All hanging
guests are in partition detection code waiting for an I/O to return
so very early maybe even the first I/O.
Reverting that commit "fixes" the hangs.
Reverting this commit for the 2.4 release. More time is needed to
investigate and correct this patch.
Did we ever find the root cause for hangs caused by this patch?
