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

    drm/i915: Allow switching away via vga-switcheroo if uninitialized

to the 6.1-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-i915-allow-switching-away-via-vga-switcheroo-if-uninitialized.patch
and it can be found in the queue-6.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From a273e95721e96885971a05f1b34cb6d093904d9d Mon Sep 17 00:00:00 2001
From: Thomas Zimmermann <[email protected]>
Date: Mon, 16 Jan 2023 12:54:23 +0100
Subject: drm/i915: Allow switching away via vga-switcheroo if uninitialized
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Thomas Zimmermann <[email protected]>

commit a273e95721e96885971a05f1b34cb6d093904d9d upstream.

Always allow switching away via vga-switcheroo if the display is
uninitalized. Instead prevent switching to i915 if the device has
not been initialized.

This issue was introduced by commit 5df7bd130818 ("drm/i915: skip
display initialization when there is no display") protected, which
protects code paths from being executed on uninitialized devices.
In the case of vga-switcheroo, we want to allow a switch away from
i915's device. So run vga_switcheroo_process_delayed_switch() and
test in the switcheroo callbacks if the i915 device is available.

Fixes: 5df7bd130818 ("drm/i915: skip display initialization when there is no 
display")
Signed-off-by: Thomas Zimmermann <[email protected]>
Reviewed-by: Alex Deucher <[email protected]>
Cc: Radhakrishna Sripada <[email protected]>
Cc: Lucas De Marchi <[email protected]>
Cc: José Roberto de Souza <[email protected]>
Cc: Jani Nikula <[email protected]>
Cc: Ville Syrjälä <[email protected]>
Cc: Jani Nikula <[email protected]>
Cc: Joonas Lahtinen <[email protected]>
Cc: Rodrigo Vivi <[email protected]>
Cc: Tvrtko Ursulin <[email protected]>
Cc: "Ville Syrjälä" <[email protected]>
Cc: Manasi Navare <[email protected]>
Cc: Stanislav Lisovskiy <[email protected]>
Cc: Imre Deak <[email protected]>
Cc: "Jouni Högander" <[email protected]>
Cc: Uma Shankar <[email protected]>
Cc: Ankit Nautiyal <[email protected]>
Cc: "Jason A. Donenfeld" <[email protected]>
Cc: Matt Roper <[email protected]>
Cc: Ramalingam C <[email protected]>
Cc: Thomas Zimmermann <[email protected]>
Cc: Andi Shyti <[email protected]>
Cc: Andrzej Hajda <[email protected]>
Cc: "José Roberto de Souza" <[email protected]>
Cc: Julia Lawall <[email protected]>
Cc: [email protected]
Cc: <[email protected]> # v5.14+
Link: 
https://patchwork.freedesktop.org/patch/msgid/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 drivers/gpu/drm/i915/i915_driver.c     |    5 +----
 drivers/gpu/drm/i915/i915_switcheroo.c |    6 +++++-
 2 files changed, 6 insertions(+), 5 deletions(-)

--- a/drivers/gpu/drm/i915/i915_driver.c
+++ b/drivers/gpu/drm/i915/i915_driver.c
@@ -1070,12 +1070,9 @@ static int i915_driver_open(struct drm_d
  */
 static void i915_driver_lastclose(struct drm_device *dev)
 {
-       struct drm_i915_private *i915 = to_i915(dev);
-
        intel_fbdev_restore_mode(dev);
 
-       if (HAS_DISPLAY(i915))
-               vga_switcheroo_process_delayed_switch();
+       vga_switcheroo_process_delayed_switch();
 }
 
 static void i915_driver_postclose(struct drm_device *dev, struct drm_file 
*file)
--- a/drivers/gpu/drm/i915/i915_switcheroo.c
+++ b/drivers/gpu/drm/i915/i915_switcheroo.c
@@ -19,6 +19,10 @@ static void i915_switcheroo_set_state(st
                dev_err(&pdev->dev, "DRM not initialized, aborting switch.\n");
                return;
        }
+       if (!HAS_DISPLAY(i915)) {
+               dev_err(&pdev->dev, "Device state not initialized, aborting 
switch.\n");
+               return;
+       }
 
        if (state == VGA_SWITCHEROO_ON) {
                drm_info(&i915->drm, "switched on\n");
@@ -44,7 +48,7 @@ static bool i915_switcheroo_can_switch(s
         * locking inversion with the driver load path. And the access here is
         * completely racy anyway. So don't bother with locking for now.
         */
-       return i915 && atomic_read(&i915->drm.open_count) == 0;
+       return i915 && HAS_DISPLAY(i915) && atomic_read(&i915->drm.open_count) 
== 0;
 }
 
 static const struct vga_switcheroo_client_ops i915_switcheroo_ops = {


Patches currently in stable-queue which might be from [email protected] are

queue-6.1/drm-i915-allow-switching-away-via-vga-switcheroo-if-uninitialized.patch

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