From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga12.intel.com ([192.55.52.136]:27883 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727030AbeJDR1R (ORCPT ); Thu, 4 Oct 2018 13:27:17 -0400 Date: Thu, 4 Oct 2018 13:34:22 +0300 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Eugeniy Paltsev Cc: dri-devel@lists.freedesktop.org, David Airlie , Alexey Brodkin , linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux-snps-arc@lists.infradead.org, Sean Paul Subject: Re: [PATCH v2] drm: fb-helper: Reject all pixel format changing requests Message-ID: <20181004103422.GL9144@intel.com> References: <20181003164538.5534-1-Eugeniy.Paltsev@synopsys.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20181003164538.5534-1-Eugeniy.Paltsev@synopsys.com> Sender: stable-owner@vger.kernel.org List-ID: On Wed, Oct 03, 2018 at 07:45:38PM +0300, Eugeniy Paltsev wrote: > drm fbdev emulation doesn't support changing the pixel format at all, > so reject all pixel format changing requests. > > Cc: stable@vger.kernel.org > Signed-off-by: Eugeniy Paltsev > --- > Changes v1->v2: > * Reject all pixel format changing request, not just the invalid ones. > > drivers/gpu/drm/drm_fb_helper.c | 91 ++++++++++++----------------------------- > 1 file changed, 26 insertions(+), 65 deletions(-) > > diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c > index 16ec93b75dbf..48598d7f673f 100644 > --- a/drivers/gpu/drm/drm_fb_helper.c > +++ b/drivers/gpu/drm/drm_fb_helper.c > @@ -1580,6 +1580,25 @@ int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd, > } > EXPORT_SYMBOL(drm_fb_helper_ioctl); > > +static bool drm_fb_pixel_format_equal(const struct fb_var_screeninfo *var_1, > + const struct fb_var_screeninfo *var_2) > +{ > + return var_1->bits_per_pixel == var_2->bits_per_pixel && > + var_1->grayscale == var_2->grayscale && > + var_1->red.offset == var_2->red.offset && > + var_1->red.length == var_2->red.length && > + var_1->red.msb_right == var_2->red.msb_right && > + var_1->green.offset == var_2->green.offset && > + var_1->green.length == var_2->green.length && > + var_1->green.msb_right == var_2->green.msb_right && > + var_1->blue.offset == var_2->blue.offset && > + var_1->blue.length == var_2->blue.length && > + var_1->blue.msb_right == var_2->blue.msb_right && > + var_1->transp.offset == var_2->transp.offset && > + var_1->transp.length == var_2->transp.length && > + var_1->transp.msb_right == var_2->transp.msb_right; > +} Could have shortened a bit with memcmp() but this works too. Reviewed-by: Ville Syrj�l� I suppose we really should be doing the same for most of the rest of var_screeninfo as we don't allow changing the timings/etc. either. > + > /** > * drm_fb_helper_check_var - implementation for &fb_ops.fb_check_var > * @var: screeninfo to check > @@ -1590,7 +1609,6 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var, > { > struct drm_fb_helper *fb_helper = info->par; > struct drm_framebuffer *fb = fb_helper->fb; > - int depth; > > if (var->pixclock != 0 || in_dbg_master()) > return -EINVAL; > @@ -1610,72 +1628,15 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var, > return -EINVAL; > } > > - switch (var->bits_per_pixel) { > - case 16: > - depth = (var->green.length == 6) ? 16 : 15; > - break; > - case 32: > - depth = (var->transp.length > 0) ? 32 : 24; > - break; > - default: > - depth = var->bits_per_pixel; > - break; > - } > - > - switch (depth) { > - case 8: > - var->red.offset = 0; > - var->green.offset = 0; > - var->blue.offset = 0; > - var->red.length = 8; > - var->green.length = 8; > - var->blue.length = 8; > - var->transp.length = 0; > - var->transp.offset = 0; > - break; > - case 15: > - var->red.offset = 10; > - var->green.offset = 5; > - var->blue.offset = 0; > - var->red.length = 5; > - var->green.length = 5; > - var->blue.length = 5; > - var->transp.length = 1; > - var->transp.offset = 15; > - break; > - case 16: > - var->red.offset = 11; > - var->green.offset = 5; > - var->blue.offset = 0; > - var->red.length = 5; > - var->green.length = 6; > - var->blue.length = 5; > - var->transp.length = 0; > - var->transp.offset = 0; > - break; > - case 24: > - var->red.offset = 16; > - var->green.offset = 8; > - var->blue.offset = 0; > - var->red.length = 8; > - var->green.length = 8; > - var->blue.length = 8; > - var->transp.length = 0; > - var->transp.offset = 0; > - break; > - case 32: > - var->red.offset = 16; > - var->green.offset = 8; > - var->blue.offset = 0; > - var->red.length = 8; > - var->green.length = 8; > - var->blue.length = 8; > - var->transp.length = 8; > - var->transp.offset = 24; > - break; > - default: > + /* > + * drm fbdev emulation doesn't support changing the pixel format at all, > + * so reject all pixel format changing requests. > + */ > + if (!drm_fb_pixel_format_equal(var, &info->var)) { > + DRM_DEBUG("fbdev emulation doesn't support changing the pixel format\n"); > return -EINVAL; > } > + > return 0; > } > EXPORT_SYMBOL(drm_fb_helper_check_var); > -- > 2.14.4 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Ville Syrj�l� Intel