Make i915's PCI device management more robust by always setting/clearing the memory access bit when enabling/disabling the device, and by consolidating this logic into helper functions.
It fixes kexec reboot issue by disabling memory access before shutting down the device, which can block unsafe and unwanted access from DMA. Link: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14598 Cc: Alex Zuo <[email protected]> Cc: Shuicheng Lin <[email protected]> Cc: Askar Safin <[email protected]> Cc: Pingfan Liu <[email protected]> Suggested-by: Chris Wilson <[email protected]> Signed-off-by: Jia Yao <[email protected]> --- drivers/gpu/drm/i915/i915_driver.c | 33 +++++++++++++++++++++++++++--- 1 file changed, 30 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c index b46cb54ef5dc..0120742e68d7 100644 --- a/drivers/gpu/drm/i915/i915_driver.c +++ b/drivers/gpu/drm/i915/i915_driver.c @@ -118,6 +118,31 @@ static const struct drm_driver i915_drm_driver; +static int i915_enable_device(struct pci_dev *pdev) { + u32 cmd; + int ret; + + ret = pci_enable_device(pdev); + if (ret) + return ret; + + pci_read_config_dword(pdev, PCI_COMMAND, &cmd); + if (!(cmd & PCI_COMMAND_MEMORY)) + pci_write_config_dword(pdev, PCI_COMMAND, cmd | PCI_COMMAND_MEMORY); + + return 0; +} + +static void i915_disable_device(struct pci_dev *pdev) { + u32 cmd; + + pci_read_config_dword(pdev, PCI_COMMAND, &cmd); + if (cmd & PCI_COMMAND_MEMORY) + pci_write_config_dword(pdev, PCI_COMMAND, cmd & ~PCI_COMMAND_MEMORY); + + pci_disable_device(pdev); +} + static int i915_workqueues_init(struct drm_i915_private *dev_priv) { /* @@ -788,7 +813,7 @@ int i915_driver_probe(struct pci_dev *pdev, const struct pci_device_id *ent) struct intel_display *display; int ret; - ret = pci_enable_device(pdev); + ret = i915_enable_device(pdev); if (ret) { pr_err("Failed to enable graphics device: %pe\n", ERR_PTR(ret)); return ret; @@ -796,7 +821,7 @@ int i915_driver_probe(struct pci_dev *pdev, const struct pci_device_id *ent) i915 = i915_driver_create(pdev, ent); if (IS_ERR(i915)) { - pci_disable_device(pdev); + i915_disable_device(pdev); return PTR_ERR(i915); } @@ -885,7 +910,7 @@ int i915_driver_probe(struct pci_dev *pdev, const struct pci_device_id *ent) enable_rpm_wakeref_asserts(&i915->runtime_pm); i915_driver_late_release(i915); out_pci_disable: - pci_disable_device(pdev); + i915_disable_device(pdev); i915_probe_error(i915, "Device initialization failed (%d)\n", ret); return ret; } @@ -1003,6 +1028,7 @@ void i915_driver_shutdown(struct drm_i915_private *i915) intel_dmc_suspend(display); + intel_pxp_fini(i915); i915_gem_suspend(i915); /* @@ -1020,6 +1046,7 @@ void i915_driver_shutdown(struct drm_i915_private *i915) enable_rpm_wakeref_asserts(&i915->runtime_pm); intel_runtime_pm_driver_last_release(&i915->runtime_pm); + i915_disable_device(to_pci_dev(i915->drm.dev)); } static bool suspend_to_idle(struct drm_i915_private *dev_priv) -- 2.34.1
