[PULL,0/1] i386: Don't automatically enable FEAT_KVM_HINTS bits

Message ID 20180416163953.31188-1-ehabkost@redhat.com
State New
Headers show

Pull-request

git://github.com/ehabkost/qemu.git tags/x86-next-pull-request

Message

Eduardo Habkost April 16, 2018, 4:39 p.m.
Last remaining fix for -rc4.

The following changes since commit 042f6a31af3d38eefc6ec995cce1d762c41d4515:

  Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2018-04-16' into staging (2018-04-16 15:30:54 +0100)

are available in the Git repository at:

  git://github.com/ehabkost/qemu.git tags/x86-next-pull-request

for you to fetch changes up to 0d914f39a77954bf5472b16130aeefe573a068f5:

  i386: Don't automatically enable FEAT_KVM_HINTS bits (2018-04-16 13:36:52 -0300)

----------------------------------------------------------------
i386: Don't automatically enable FEAT_KVM_HINTS bits

Bug fix for "-cpu host" with newer kernels.

----------------------------------------------------------------

Eduardo Habkost (1):
  i386: Don't automatically enable FEAT_KVM_HINTS bits

 target/i386/cpu.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

Comments

Peter Maydell April 16, 2018, 4:57 p.m. | #1
On 16 April 2018 at 17:39, Eduardo Habkost <ehabkost@redhat.com> wrote:
> Last remaining fix for -rc4.
>
> The following changes since commit 042f6a31af3d38eefc6ec995cce1d762c41d4515:
>
>   Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2018-04-16' into staging (2018-04-16 15:30:54 +0100)
>
> are available in the Git repository at:
>
>   git://github.com/ehabkost/qemu.git tags/x86-next-pull-request
>
> for you to fetch changes up to 0d914f39a77954bf5472b16130aeefe573a068f5:
>
>   i386: Don't automatically enable FEAT_KVM_HINTS bits (2018-04-16 13:36:52 -0300)
>
> ----------------------------------------------------------------
> i386: Don't automatically enable FEAT_KVM_HINTS bits
>
> Bug fix for "-cpu host" with newer kernels.
>
> ----------------------------------------------------------------

Is this a regression since 2.11 ?

thanks
-- PMM
Eduardo Habkost April 16, 2018, 5:42 p.m. | #2
On Mon, Apr 16, 2018 at 05:57:35PM +0100, Peter Maydell wrote:
> On 16 April 2018 at 17:39, Eduardo Habkost <ehabkost@redhat.com> wrote:
> > Last remaining fix for -rc4.
> >
> > The following changes since commit 042f6a31af3d38eefc6ec995cce1d762c41d4515:
> >
> >   Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2018-04-16' into staging (2018-04-16 15:30:54 +0100)
> >
> > are available in the Git repository at:
> >
> >   git://github.com/ehabkost/qemu.git tags/x86-next-pull-request
> >
> > for you to fetch changes up to 0d914f39a77954bf5472b16130aeefe573a068f5:
> >
> >   i386: Don't automatically enable FEAT_KVM_HINTS bits (2018-04-16 13:36:52 -0300)
> >
> > ----------------------------------------------------------------
> > i386: Don't automatically enable FEAT_KVM_HINTS bits
> >
> > Bug fix for "-cpu host" with newer kernels.
> >
> > ----------------------------------------------------------------
> 
> Is this a regression since 2.11 ?

Yes.
Eduardo Habkost April 16, 2018, 5:46 p.m. | #3
On Mon, Apr 16, 2018 at 02:42:52PM -0300, Eduardo Habkost wrote:
> On Mon, Apr 16, 2018 at 05:57:35PM +0100, Peter Maydell wrote:
> > On 16 April 2018 at 17:39, Eduardo Habkost <ehabkost@redhat.com> wrote:
> > > Last remaining fix for -rc4.
> > >
> > > The following changes since commit 042f6a31af3d38eefc6ec995cce1d762c41d4515:
> > >
> > >   Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2018-04-16' into staging (2018-04-16 15:30:54 +0100)
> > >
> > > are available in the Git repository at:
> > >
> > >   git://github.com/ehabkost/qemu.git tags/x86-next-pull-request
> > >
> > > for you to fetch changes up to 0d914f39a77954bf5472b16130aeefe573a068f5:
> > >
> > >   i386: Don't automatically enable FEAT_KVM_HINTS bits (2018-04-16 13:36:52 -0300)
> > >
> > > ----------------------------------------------------------------
> > > i386: Don't automatically enable FEAT_KVM_HINTS bits
> > >
> > > Bug fix for "-cpu host" with newer kernels.
> > >
> > > ----------------------------------------------------------------
> > 
> > Is this a regression since 2.11 ?
> 
> Yes.

For reference, it was introduced by:

commit be7773268d98176489483a315d3e2323cb0615b9
Author: Wanpeng Li <wanpengli@tencent.com>
Date:   Fri Feb 9 06:15:25 2018 -0800

    target-i386: add KVM_HINTS_DEDICATED performance hint
    
    Add KVM_HINTS_DEDICATED performance hint, guest checks this feature bit
    to determine if they run on dedicated vCPUs, allowing optimizations such
    as usage of qspinlocks.

Sorry for not including a "Fixes:" tag in the commit message.  If
you think it's worth it, I can redo the pull request with it.
Peter Maydell April 16, 2018, 5:49 p.m. | #4
On 16 April 2018 at 18:46, Eduardo Habkost <ehabkost@redhat.com> wrote:
> On Mon, Apr 16, 2018 at 02:42:52PM -0300, Eduardo Habkost wrote:
>> On Mon, Apr 16, 2018 at 05:57:35PM +0100, Peter Maydell wrote:
>> > On 16 April 2018 at 17:39, Eduardo Habkost <ehabkost@redhat.com> wrote:
>> > > Last remaining fix for -rc4.
>> > >
>> > > The following changes since commit 042f6a31af3d38eefc6ec995cce1d762c41d4515:
>> > >
>> > >   Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2018-04-16' into staging (2018-04-16 15:30:54 +0100)
>> > >
>> > > are available in the Git repository at:
>> > >
>> > >   git://github.com/ehabkost/qemu.git tags/x86-next-pull-request
>> > >
>> > > for you to fetch changes up to 0d914f39a77954bf5472b16130aeefe573a068f5:
>> > >
>> > >   i386: Don't automatically enable FEAT_KVM_HINTS bits (2018-04-16 13:36:52 -0300)
>> > >
>> > > ----------------------------------------------------------------
>> > > i386: Don't automatically enable FEAT_KVM_HINTS bits
>> > >
>> > > Bug fix for "-cpu host" with newer kernels.
>> > >
>> > > ----------------------------------------------------------------
>> >
>> > Is this a regression since 2.11 ?
>>
>> Yes.
>
> For reference, it was introduced by:
>
> commit be7773268d98176489483a315d3e2323cb0615b9
> Author: Wanpeng Li <wanpengli@tencent.com>
> Date:   Fri Feb 9 06:15:25 2018 -0800
>
>     target-i386: add KVM_HINTS_DEDICATED performance hint
>
>     Add KVM_HINTS_DEDICATED performance hint, guest checks this feature bit
>     to determine if they run on dedicated vCPUs, allowing optimizations such
>     as usage of qspinlocks.
>
> Sorry for not including a "Fixes:" tag in the commit message.  If
> you think it's worth it, I can redo the pull request with it.

No, that's fine. I'm just checking that we're all on the same page
about the level of fix that goes into a late-stage rc. Particularly
as we get past rc2 or so, it's definitely helpful to me if pull
request cover letters include justifications for why the changes
should go in.

thanks
-- PMM
Peter Maydell April 17, 2018, 11:03 a.m. | #5
On 16 April 2018 at 17:39, Eduardo Habkost <ehabkost@redhat.com> wrote:
> Last remaining fix for -rc4.
>
> The following changes since commit 042f6a31af3d38eefc6ec995cce1d762c41d4515:
>
>   Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2018-04-16' into staging (2018-04-16 15:30:54 +0100)
>
> are available in the Git repository at:
>
>   git://github.com/ehabkost/qemu.git tags/x86-next-pull-request
>
> for you to fetch changes up to 0d914f39a77954bf5472b16130aeefe573a068f5:
>
>   i386: Don't automatically enable FEAT_KVM_HINTS bits (2018-04-16 13:36:52 -0300)
>
> ----------------------------------------------------------------
> i386: Don't automatically enable FEAT_KVM_HINTS bits
>
> Bug fix for "-cpu host" with newer kernels.
>
> ----------------------------------------------------------------
>
> Eduardo Habkost (1):
>   i386: Don't automatically enable FEAT_KVM_HINTS bits
>

Applied, thanks.

-- PMM