drm/i915: move intel_gvt_init() level higher

Both initialisation and removal of GVT happen at different abstraction
levels. Hence caller of i915_driver_hw_probe() has no way of knowing
status of intel_gvt_init(). This can lead to an unbalanced number of
calls of intel_gvt_init() and intel_gvt_driver_remove() since GVT error
path is currently handled in i915_driver_probe(). One such scenario has
been seen with i915_driver_hw_probe() fault injection, which caused
double entry deletion and list corruption.

Move intel_gvt_init() up to i915_driver_probe(). Add out_cleanup_gvt
error path for removing gvt. Trigger it only after intel_gvt_init()
succeeded.

In case intel_gvt_init() failed, theoretically we should follow err_msi
error path. That is actually impossible since call to intel_gvt_init()
unconditionally returns 0, although it claims to return negative error
code on failure. Thus follow standard out_cleanup_hw error path on a
hypothetical future intel_gvt_init() failure. Remove err_msi label from
i915_driver_hw_probe() since intel_gvt_init() was the only user of it.

Changelog:
v1->v2
- don't move err_msi error path from i915_driver_hw_probe (Jani)
- rewrite commit message

Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/15481
Signed-off-by: Michał Grzelak <michal.grzelak@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patch.msgid.link/20260129090129.2601661-2-michal.grzelak@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
index f8a1f10d487474f48b393c87fe8fc78b47e5be51..c01a35ecfa2fe6e43759c924f834831aed53002c 100644 (file)
--- a/drivers/gpu/drm/i915/i915_driver.c
+++ b/drivers/gpu/drm/i915/i915_driver.c
@@ -557,10 +557,6 @@ static int i915_driver_hw_probe(struct drm_i915_private *dev_priv)
                        drm_dbg(&dev_priv->drm, "can't enable MSI");
        }
 
-       ret = intel_gvt_init(dev_priv);
-       if (ret)
-               goto err_msi;
-
        intel_opregion_setup(display);
 
        ret = i915_pcode_init(dev_priv);
@@ -581,7 +577,6 @@ static int i915_driver_hw_probe(struct drm_i915_private *dev_priv)
 
 err_opregion:
        intel_opregion_cleanup(display);
-err_msi:
        if (pdev->msi_enabled)
                pci_disable_msi(pdev);
 err_mem_regions:
@@ -871,9 +866,13 @@ int i915_driver_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
        if (ret < 0)
                goto out_cleanup_mmio;
 
+       ret = intel_gvt_init(i915);
+       if (ret)
+               goto out_cleanup_hw;
+
        ret = intel_display_driver_probe_noirq(display);
        if (ret < 0)
-               goto out_cleanup_hw;
+               goto out_cleanup_gvt;
 
        ret = intel_irq_install(i915);
        if (ret)
@@ -922,6 +921,8 @@ out_cleanup_irq:
        intel_irq_uninstall(i915);
 out_cleanup_modeset:
        intel_display_driver_remove_nogem(display);
+out_cleanup_gvt:
+       intel_gvt_driver_remove(i915);
 out_cleanup_hw:
        i915_driver_hw_remove(i915);
        intel_memory_regions_driver_release(i915);
@@ -929,7 +930,6 @@ out_cleanup_hw:
        i915_gem_drain_freed_objects(i915);
        i915_ggtt_driver_late_release(i915);
 out_cleanup_mmio:
-       intel_gvt_driver_remove(i915);
        i915_driver_mmio_release(i915);
 out_runtime_pm_put:
        enable_rpm_wakeref_asserts(&i915->runtime_pm);