Re: [Qemu-devel] [PATCH 2/6] Move paio_cancel() to new infrastructure.

["Venkateswararao Jujjuri (JV)" <jvrao@linux.vnet.ibm.com>]

On 11/19/2010 2:07 AM, Stefan Hajnoczi wrote:
> On Thu, Nov 18, 2010 at 6:06 PM, Arun R Bharadwaj
> <arun@linux.vnet.ibm.com> wrote:
>> Move paio_cancel() to new infrastructure and introduce
>> the necessary APIs for this.
>>
>> Signed-off-by: Arun R Bharadwaj <arun@linux.vnet.ibm.com>
>> ---
>>  posix-aio-compat.c |   92 ++++++++++++++++++++++++++++++++++++++++++----------
>>  1 files changed, 74 insertions(+), 18 deletions(-)
> 
> This commit is not a safe step to make.  paio_cancel() is going to
> cause uninitialized threadlet structures to be accessed.
> 
> You split the patches up into smaller commits for easier review.
> Unfortunately this particular commit will result in a QEMU which
> builds successfully but has undefined behavior at runtime - it may
> crash or do random things.
> 
> That's a problem for git-bisect(1) and in general for anyone who
> assumes they can build QEMU at an arbitrary point in the commit
> history.  It's really important to preserve bisectability, because
> once commits get introduced that build bad QEMUs we can no longer have
> confidence in bisect!
> 
> Please split up commits so they introduce a new feature incrementally
> but work properly at each step in the series.

Arun, you may move this to later part of the series to take care of this bisect
issue.

Thanks,
JV

> 
> Stefan
>