drm/i915/switcheroo: check for NULL before dereferencing

Both i915_switcheroo_set_state() and i915_switcheroo_can_switch() check
for i915 == NULL. Commit d2e184f8e16a ("drm/i915/switcheroo: pass
display to HAS_DISPLAY()") started dereferencing it before the NULL
check. Fix it.

Fixes: d2e184f8e16a ("drm/i915/switcheroo: pass display to HAS_DISPLAY()")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202508160035.hmzuKiww-lkp@intel.com/
Cc: Gustavo Sousa <gustavo.sousa@intel.com>
Reviewed-by: Gustavo Sousa <gustavo.sousa@intel.com>
Link: https://lore.kernel.org/r/20250818071605.2541523-1-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/i915_switcheroo.c b/drivers/gpu/drm/i915/i915_switcheroo.c
index 231d274977069d28777bd348324bf2bef9cd4172..3a95a55b2e87ab4580a2bdb9482a70c54048e72c 100644 (file)
--- a/drivers/gpu/drm/i915/i915_switcheroo.c
+++ b/drivers/gpu/drm/i915/i915_switcheroo.c
@@ -15,7 +15,7 @@ static void i915_switcheroo_set_state(struct pci_dev *pdev,
                                      enum vga_switcheroo_state state)
 {
        struct drm_i915_private *i915 = pdev_to_i915(pdev);
-       struct intel_display *display = i915->display;
+       struct intel_display *display = i915 ? i915->display : NULL;
        pm_message_t pmm = { .event = PM_EVENT_SUSPEND };
 
        if (!i915) {
@@ -45,7 +45,7 @@ static void i915_switcheroo_set_state(struct pci_dev *pdev,
 static bool i915_switcheroo_can_switch(struct pci_dev *pdev)
 {
        struct drm_i915_private *i915 = pdev_to_i915(pdev);
-       struct intel_display *display = i915->display;
+       struct intel_display *display = i915 ? i915->display : NULL;
 
        /*
         * FIXME: open_count is protected by drm_global_mutex but that would lead to