drm: use "0" instead of "" for deprecated driver date

libdrm does not like the empty string for driver date. Use "0" instead,
which has been used by virtio previously.

Reported-by: Steven Price <steven.price@arm.com>
Closes: https://lore.kernel.org/r/9d0cff47-308e-4b11-a9f3-4157dc26b6fa@arm.com
Fixes: 7fb8af6798e8 ("drm: deprecate driver date")
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240510090951.3398882-1-jani.nikula@intel.com
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Steven Price <steven.price@arm.com>
Reviewed-by: Simon Ser <contact@emersion.fr>

diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
index 89feb7306e477e1f804da0969a2c11324048aa2e..51f39912866fc7c49f8ce7a2f601b3aa9d18d8ae 100644 (file)
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -530,9 +530,9 @@ int drm_version(struct drm_device *dev, void *data,
        err = drm_copy_field(version->name, &version->name_len,
                        dev->driver->name);
 
-       /* Driver date is deprecated. Return the empty string. */
+       /* Driver date is deprecated. Userspace expects a non-empty string. */
        if (!err)
-               err = drm_copy_field(version->date, &version->date_len, "");
+               err = drm_copy_field(version->date, &version->date_len, "0");
        if (!err)
                err = drm_copy_field(version->desc, &version->desc_len,
                                dev->driver->desc);