Re: [syzbot] [PATCH] test divide error in drm_mode_debug_printmodeline

[syzbot]

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Subject: [PATCH] test divide error in drm_mode_debug_printmodeline
Author: lizhi.xu@xxxxxxxxxxxxx

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git ac347a0655db

diff --git a/include/drm/drm_modes.h b/include/drm/drm_modes.h
index c613f0abe9dc..19e37e92dfaf 100644
--- a/include/drm/drm_modes.h
+++ b/include/drm/drm_modes.h
@@ -422,7 +422,7 @@ struct drm_display_mode {
 /**
  * DRM_MODE_FMT - printf string for &struct drm_display_mode
  */
-#define DRM_MODE_FMT    "\"%s\": %d %d %d %d %d %d %d %d %d %d 0x%x 0x%x"
+#define DRM_MODE_FMT    "\"%s\": %llu %d %d %d %d %d %d %d %d %d 0x%x 0x%x"
 
 /**
  * DRM_MODE_ARG - printf arguments for &struct drm_display_mode
@@ -526,7 +526,7 @@ static inline int of_get_drm_panel_display_mode(struct device_node *np,
 #endif
 
 void drm_mode_set_name(struct drm_display_mode *mode);
-int drm_mode_vrefresh(const struct drm_display_mode *mode);
+long drm_mode_vrefresh(const struct drm_display_mode *mode);
 void drm_mode_get_hv_timing(const struct drm_display_mode *mode,
 			    int *hdisplay, int *vdisplay);
 
diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index ac9a406250c5..6f376001728c 100644
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -1283,9 +1283,9 @@ EXPORT_SYMBOL(drm_mode_set_name);
  * @modes's vrefresh rate in Hz, rounded to the nearest integer. Calculates the
  * value first if it is not yet set.
  */
-int drm_mode_vrefresh(const struct drm_display_mode *mode)
+long drm_mode_vrefresh(const struct drm_display_mode *mode)
 {
-	unsigned int num, den;
+	unsigned long num, den;
 
 	if (mode->htotal == 0 || mode->vtotal == 0)
 		return 0;