From mboxrd@z Thu Jan 1 00:00:00 1970 From: Woody Suwalski Subject: Re: [PATCH] 4.15 vmgfx boot warning Date: Fri, 15 Dec 2017 19:01:34 -0500 Message-ID: <1d88409f-23c4-6706-7111-00f2d13f3351@gmail.com> References: <20171213212522.GC16788@promb-2n-dhcp36.eng.vmware.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20171213212522.GC16788@promb-2n-dhcp36.eng.vmware.com> Sender: linux-kernel-owner@vger.kernel.org To: Sinclair Yeh Cc: DRI mailing list , LKML , Dave Airlie , Daniel Vetter List-Id: dri-devel@lists.freedesktop.org Sinclair Yeh wrote: > Hi Woody, > > On Wed, Nov 22, 2017 at 04:05:50PM -0500, Woody Suwalski wrote: >> The 4.15 vmwgfx driver shows a warning during boot (32 bit x86) >> It is caused by a mismatch between the result of vmw_enable_vblank() and >> what the drm_atomic_helper expects: >>    /... >>    ret = drm_crtc_vblank_get(crtc); >>    WARN_ONCE(ret != -EINVAL, "driver forgot to call >> drm_crtc_vblank_off()\n"); > This doesn't apply to us because we don't have vblank support, and so > -ENOSYS seems to be the right error. > > In the commit message for 84014b0a39ee, it does state a check for this > condition, but the check itself is based on dev->irq_enabled. > > Is there another way to check for vblank support? > > > >>    /... >> >> Signed-off by: Woody Suwalski >> >> --- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c    2017-11-22 15:29:46.511674079 >> -0500 >> +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c    2017-11-22 15:30:35.344559592 >> -0500 >> @@ -1869,7 +1869,7 @@ u32 vmw_get_vblank_counter(struct drm_de >>   */ >>  int vmw_enable_vblank(struct drm_device *dev, unsigned int pipe) >>  { >> -    return -ENOSYS; >> +    return -EINVAL; >>  } >> >>  /** >> Sinclair, it is a valid stand, so I guess it is time to ask Daniel... Would it be OK to convert the WARN_ONCE statement in drm_atomic_helper to recognize ENOSYS as a valid error? Something like WARN_ONCE((ret != -EINVAL && ret != _ENOSYS), "driver forgot to call drm_crtc_vblank_off()\n"); Thanks, Woody