RE: [PATCH 1/6] Drivers: hv: vmbus: Perform device register in the per-channel work element

KY Srinivasan
2015-03-17T04:50:47Z

> -----Original Message-----
> From: Greg KH [mailto:gregkh@linuxfoundation.org]
> Sent: Monday, March 16, 2015 1:22 PM
> To: KY Srinivasan
> Cc: apw@canonical.com; devel@linuxdriverproject.org; olaf@aepfle.de;
> linux-kernel@vger.kernel.org
> Subject: Re: [PATCH 1/6] Drivers: hv: vmbus: Perform device register in the
> per-channel work element
>
> On Thu, Mar 12, 2015 at 02:16:23PM +0000, KY Srinivasan wrote:
> >
> >
> > > -----Original Message-----
> > > From: Greg KH [mailto:gregkh@linuxfoundation.org]
> > > Sent: Thursday, March 12, 2015 6:29 AM
> > > To: KY Srinivasan
> > > Cc: apw@canonical.com; devel@linuxdriverproject.org; olaf@aepfle.de;
> > > linux-kernel@vger.kernel.org
> > > Subject: Re: [PATCH 1/6] Drivers: hv: vmbus: Perform device register
> > > in the per-channel work element
> > >
> > > On Thu, Mar 12, 2015 at 01:12:29PM +0000, KY Srinivasan wrote:
> > > >
> > > >
> > > > > -----Original Message-----
> > > > > From: Greg KH [mailto:gregkh@linuxfoundation.org]
> > > > > Sent: Thursday, March 12, 2015 2:03 AM
> > > > > To: KY Srinivasan
> > > > > Cc: linux-kernel@vger.kernel.org; devel@linuxdriverproject.org;
> > > > > olaf@aepfle.de; apw@canonical.com; vkuznets@redhat.com
> > > > > Subject: Re: [PATCH 1/6] Drivers: hv: vmbus: Perform device
> > > > > register in the per-channel work element
> > > > >
> > > > > On Thu, Mar 12, 2015 at 10:02:24AM +0100, Greg KH wrote:
> > > > > > On Wed, Mar 11, 2015 at 06:56:54PM -0700, K. Y. Srinivasan wrote:
> > > > > > > This patch is a continuation of the rescind handling cleanup work.
> > > > > > > We cannot block in the global message handling work context
> > > > > > > especially if we are blocking waiting for the host to wake
> > > > > > > us up. I would like to thank Dexuan Cui
> > > > > > > <decui@microsoft.com> for observing
> > > > > this problem.
> > > > > > >
> > > > > > > The current Linux 4.0 RC3 tree is broken and this patch
> > > > > > > fixes the
> > > problem.
> > > > > > >
> > > > > > > Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
> > > > > > > ---
> > > > > > > drivers/hv/channel_mgmt.c | 143
> > > > > +++++++++++++++++++++++++++++++-------------
> > > > > > > drivers/hv/connection.c | 6 ++-
> > > > > > > drivers/hv/hyperv_vmbus.h | 2 +-
> > > > > > > 3 files changed, 107 insertions(+), 44 deletions(-)
> > > > > >
> > > > > > This is a very big patch so late in the -rc cycle. Is there
> > > > > > some patch that got merged in 4.0-rc1 that I should be
> > > > > > reverting instead to fix things up?
> > > > >
> > > > > Make that, "this is a very large patch set", not just one patch.
> > > > > I can't take all of these this late, sorry. Please just tell me what to
> revert.
> > > >
> > > > Greg,
> > > >
> > > > Would it be possible to pick up two patches. I could prune this
> > > > down to two. The two I want you to pick up are (in the order of
> importance):
> > > >
> > > > [PATCH 1/6] Drivers: hv: vmbus: Perform device register in the
> > > > per-channel work element [PATCH 2/6] Drivers: hv: hv_balloon: keep
> > > > locks balanced on add_memory() failure
> > > >
> > > > If you could pickup an additional patch that would be:
> > > >
> > > > [PATCH 6/6] Drivers: hv: vmbus: Fix a bug in rescind processing in
> > > > vmbus_close_internal()
> > > >
> > > > The first one is the most important one and if you can only pickup
> > > > one, the
> > > first one is the one I want you to pick up.
> > >
> > > You aren't answering my question, what happened that caused these to
> > > become an error and break the 4.0-rc tree? Shouldn't I just revert
> > > a recent change here? Or has things always been broken and no one
> > > has noticed it before?
> >
> > commit 2dd37cb81580dce6dfb8c5a7d5c37b904a188ae7
> >
> > introduced the bug (committed on Feb 28th). This patch cleaned up the
> > rescind handling code.
> >
> > The patches I sent a few days later:
> >
> > Drivers: hv: vmbus: Perform device register in the per-channel work
> > element fixed it.
> >
> > Drivers: hv: vmbus: Fix a bug in rescind processing in
> > vmbus_close_internal()
> >
> > Fixed the bugs.
>
> Ok, commit 2dd37cb81580dce6dfb8c5a7d5c37b904a188ae7 is on my char-
> misc-next branch, and has nothing to do with 4.0-final. So why do you think
> anything needs to be done for 4.0?
>
> Please take a look at my tree, at Linus's tree, and figure out exactly what
> needs to be fixed where, and resend me patches that explicitly says which
> branch for me to apply them to (char-linus for patches that need to go for
> 4.0-final, char-next for patches that need to go into
> 4.1-rc1.)

You are right, the offending commit is NOT in 4.0-rc4 tree that
I looked at earlier this afternoon.

>
> I'm again dropping all of your pending patches in my to-apply queue, as it's all
> just too confusing here and no one seems to know what is going on (myself
> included.)

Sorry about the confusion. My mistake; last week I looked at a test tree that had the
offending commit and I was told that the tree was the 4.0-rc3 tree.

I will resend the patches that need to go into 4.1-rc1.

Regards,

K. Y