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 <stable@xxxxxxxxxxxxxxx> know about it. >From a273e95721e96885971a05f1b34cb6d093904d9d Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann <tzimmermann@xxxxxxx> 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 <tzimmermann@xxxxxxx> 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 <tzimmermann@xxxxxxx> Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx> Cc: Radhakrishna Sripada <radhakrishna.sripada@xxxxxxxxx> Cc: Lucas De Marchi <lucas.demarchi@xxxxxxxxx> Cc: José Roberto de Souza <jose.souza@xxxxxxxxx> Cc: Jani Nikula <jani.nikula@xxxxxxxxx> Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx> Cc: "Ville Syrjälä" <ville.syrjala@xxxxxxxxxxxxxxx> Cc: Manasi Navare <manasi.d.navare@xxxxxxxxx> Cc: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx> Cc: Imre Deak <imre.deak@xxxxxxxxx> Cc: "Jouni Högander" <jouni.hogander@xxxxxxxxx> Cc: Uma Shankar <uma.shankar@xxxxxxxxx> Cc: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx> Cc: "Jason A. Donenfeld" <Jason@xxxxxxxxx> Cc: Matt Roper <matthew.d.roper@xxxxxxxxx> Cc: Ramalingam C <ramalingam.c@xxxxxxxxx> Cc: Thomas Zimmermann <tzimmermann@xxxxxxx> Cc: Andi Shyti <andi.shyti@xxxxxxxxxxxxxxx> Cc: Andrzej Hajda <andrzej.hajda@xxxxxxxxx> Cc: "José Roberto de Souza" <jose.souza@xxxxxxxxx> Cc: Julia Lawall <Julia.Lawall@xxxxxxxx> Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx Cc: <stable@xxxxxxxxxxxxxxx> # v5.14+ Link: https://patchwork.freedesktop.org/patch/msgid/20230116115425.13484-2-tzimmermann@xxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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 tzimmermann@xxxxxxx are queue-6.1/drm-i915-allow-switching-away-via-vga-switcheroo-if-uninitialized.patch