[PATCH] drm: use "0" instead of "" for deprecated driver date

[Jani Nikula]

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 at 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 at intel.com>
---
 drivers/gpu/drm/drm_ioctl.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
index 89feb7306e47..51f39912866f 100644
--- 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);
-- 
2.39.2