| Message ID | 20180906072850.11150-1-kraxel@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm: refuse ADDFB2 ioctl for broken bigendian drivers | expand |
On Thu, Sep 06, 2018 at 09:28:50AM +0200, Gerd Hoffmann wrote: > Drivers must set the quirk_addfb_prefer_host_byte_order quirk to make > the drm_mode_addfb() compat code work correctly on bigendian machines. > > If they don't they interpret pixel_format values incorrectly for bug > compatibility, which in turn implies the ADDFB2 ioctl does not work > correctly then. So block it to make userspace fallback to ADDFB. > > Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> > --- > drivers/gpu/drm/drm_ioctl.c | 25 ++++++++++++++++++++++++- > 1 file changed, 24 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c > index ea10e9a26a..08e48bda23 100644 > --- a/drivers/gpu/drm/drm_ioctl.c > +++ b/drivers/gpu/drm/drm_ioctl.c > @@ -469,6 +469,29 @@ static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value) > return 0; > } > > +static int drm_mode_addfb2_check(struct drm_device *dev, > + void *data, struct drm_file *file_priv) > +{ > +#ifdef __BIG_ENDIAN > + if (!dev->mode_config.quirk_addfb_prefer_host_byte_order) { > + /* > + * Drivers must set the > + * quirk_addfb_prefer_host_byte_order quirk to make > + * the drm_mode_addfb() compat code work correctly on > + * bigendian machines. > + * > + * If they don't they interpret pixel_format values > + * incorrectly for bug compatibility, which in turn > + * implies the ADDFB2 ioctl does not work correctly > + * then. So block it to make userspace fallback to > + * ADDFB. > + */ DRM_DEBUG_KMS would be good here I think, just to help userspace people figure out why they got an -EINVAL. > + return -EINVAL; > + } > +#endif > + return drm_mode_addfb2(dev, data, file_priv); I think it'd be better if we have all the addfb code in drm_framebuffer.c. So leave the function name, and extract the common code into __drm_mode_addfb2 helper. With these two nits addressed: Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> > +} > + > /* > * Get version information > * > @@ -645,7 +668,7 @@ static const struct drm_ioctl_desc drm_ioctls[] = { > DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_UNLOCKED), > DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_UNLOCKED), > DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, DRM_UNLOCKED), > - DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_UNLOCKED), > + DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_check, DRM_UNLOCKED), > DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, DRM_UNLOCKED), > DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_UNLOCKED), > DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_UNLOCKED), > -- > 2.9.3 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index ea10e9a26a..08e48bda23 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -469,6 +469,29 @@ static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value) return 0; } +static int drm_mode_addfb2_check(struct drm_device *dev, + void *data, struct drm_file *file_priv) +{ +#ifdef __BIG_ENDIAN + if (!dev->mode_config.quirk_addfb_prefer_host_byte_order) { + /* + * Drivers must set the + * quirk_addfb_prefer_host_byte_order quirk to make + * the drm_mode_addfb() compat code work correctly on + * bigendian machines. + * + * If they don't they interpret pixel_format values + * incorrectly for bug compatibility, which in turn + * implies the ADDFB2 ioctl does not work correctly + * then. So block it to make userspace fallback to + * ADDFB. + */ + return -EINVAL; + } +#endif + return drm_mode_addfb2(dev, data, file_priv); +} + /* * Get version information * @@ -645,7 +668,7 @@ static const struct drm_ioctl_desc drm_ioctls[] = { DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, DRM_UNLOCKED), - DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2, DRM_UNLOCKED), + DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_check, DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_UNLOCKED),
Drivers must set the quirk_addfb_prefer_host_byte_order quirk to make the drm_mode_addfb() compat code work correctly on bigendian machines. If they don't they interpret pixel_format values incorrectly for bug compatibility, which in turn implies the ADDFB2 ioctl does not work correctly then. So block it to make userspace fallback to ADDFB. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> --- drivers/gpu/drm/drm_ioctl.c | 25 ++++++++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-)