Patch "drm/vmwgfx: Fix two list_for_each loop exit tests" has been added to the 4.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    drm/vmwgfx: Fix two list_for_each loop exit tests

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-vmwgfx-fix-two-list_for_each-loop-exit-tests.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 6dcde46075c2037ddc0b97ecc162580e29cc430d
Author: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Date:   Fri Jun 26 13:39:59 2020 +0300

    drm/vmwgfx: Fix two list_for_each loop exit tests
    
    [ Upstream commit 4437c1152ce0e57ab8f401aa696ea6291cc07ab1 ]
    
    These if statements are supposed to be true if we ended the
    list_for_each_entry() loops without hitting a break statement but they
    don't work.
    
    In the first loop, we increment "i" after the "if (i == unit)" condition
    so we don't necessarily know that "i" is not equal to unit at the end of
    the loop.
    
    In the second loop we exit when mode is not pointing to a valid
    drm_display_mode struct so it doesn't make sense to check "mode->type".
    
    Fixes: a278724aa23c ("drm/vmwgfx: Implement fbdev on kms v2")
    Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
    Reviewed-by: Roland Scheidegger <sroland@xxxxxxxxxx>
    Signed-off-by: Roland Scheidegger <sroland@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
index 9b97f70fbb3df..0b7427d474feb 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -2086,7 +2086,7 @@ int vmw_kms_fbdev_init_data(struct vmw_private *dev_priv,
 		++i;
 	}
 
-	if (i != unit) {
+	if (&con->head == &dev_priv->dev->mode_config.connector_list) {
 		DRM_ERROR("Could not find initial display unit.\n");
 		return -EINVAL;
 	}
@@ -2108,13 +2108,13 @@ int vmw_kms_fbdev_init_data(struct vmw_private *dev_priv,
 			break;
 	}
 
-	if (mode->type & DRM_MODE_TYPE_PREFERRED)
-		*p_mode = mode;
-	else {
+	if (&mode->head == &con->modes) {
 		WARN_ONCE(true, "Could not find initial preferred mode.\n");
 		*p_mode = list_first_entry(&con->modes,
 					   struct drm_display_mode,
 					   head);
+	} else {
+		*p_mode = mode;
 	}
 
 	return 0;