You mean intel_pxp_fini(i915) ? This is because mei_me_shutdown is called after i915_driver_shutdown in pci_device_shutdown sequence. If we don't close pxp in advance, it will cause
[ 295.584775] i915 0000:00:02.0: [drm] *ERROR* gt: MMIO unreliable (forcewake register returns 0xFFFFFFFF)! Since we disabled PCI_COMMAND_MEMORY in i915_driver_shutdown Thanks, Jia -----Original Message----- From: Ville Syrjälä <[email protected]> Sent: Tuesday, October 7, 2025 2:25 PM To: Yao, Jia <[email protected]> Cc: [email protected]; Zuo, Alex <[email protected]>; Lin, Shuicheng <[email protected]>; Askar Safin <[email protected]>; Pingfan Liu <[email protected]>; Chris Wilson <[email protected]> Subject: Re: [PATCH v2] drm/i915: Setting/clearing the memory access bit when en/disabling i915 On Tue, Oct 07, 2025 at 08:25:14PM +0000, Jia Yao wrote: > 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. > > v2: > - follow brace style > > 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 | 35 > +++++++++++++++++++++++++++--- > 1 file changed, 32 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_driver.c > b/drivers/gpu/drm/i915/i915_driver.c > index b46cb54ef5dc..766f85726b67 100644 > --- a/drivers/gpu/drm/i915/i915_driver.c > +++ b/drivers/gpu/drm/i915/i915_driver.c > @@ -118,6 +118,33 @@ > > 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; > +} NAK. If the pci code is broken then fix the problem there. Do not add ugly hacks into random drivers. > + > +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 +815,7 @@ 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 +823,7 @@ 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 +912,7 @@ 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 +1030,7 @@ void i915_driver_shutdown(struct > drm_i915_private *i915) > > intel_dmc_suspend(display); > > + intel_pxp_fini(i915); What is that doing in this patch? > i915_gem_suspend(i915); > > /* > @@ -1020,6 +1048,7 @@ 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 -- Ville Syrjälä Intel
