CPU mappings created before a device wedge can keep valid PTEs and continue accessing VRAM. Mapping new faults to a dummy page does not replace these existing mappings.
Use the common device I/O SRCU gate to wait for active CPU faults to finish. Then invalidate all tracked VRAM mappings. Faults starting after the wedge use the per-BO dummy page. This ensures userspace is notified only after existing VRAM mappings have been removed. Also invalidate existing VRAM CPU mappings during PCI error recovery. After setting in_reset and draining active faults, remove the mappings before disabling PCI. Later faults use the dummy page because device I/O is blocked. v2: - Drain active faults before invalidating VRAM mappings v3: - Use the common DRM device SRCU gate instead of a separate VRAM fault SRCU domain. - Invalidate existing VRAM CPU mappings before PCI disable during AER. (Sashiko) Cc: Matthew Brost <[email protected]> Cc: Thomas Hellström <[email protected]> Cc: Himal Prasad Ghimiray <[email protected]> Cc: Rodrigo Vivi <[email protected]> Assisted-by: LLM Signed-off-by: Arvind Yadav <[email protected]> --- drivers/gpu/drm/xe/xe_bo.c | 20 ++++++++++++++++++++ drivers/gpu/drm/xe/xe_bo.h | 1 + drivers/gpu/drm/xe/xe_device.c | 4 ++++ drivers/gpu/drm/xe/xe_pci_error.c | 4 ++++ 4 files changed, 29 insertions(+) diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c index 6efcf3f5dda8..2b3c000b7f94 100644 --- a/drivers/gpu/drm/xe/xe_bo.c +++ b/drivers/gpu/drm/xe/xe_bo.c @@ -4235,6 +4235,26 @@ void xe_bo_runtime_pm_release_mmap_offset(struct xe_bo *bo) list_del_init(&bo->vram_userfault_link); } +/** + * xe_bo_wedged_invalidate_mmaps - Invalidate CPU mappings backed by VRAM + * @xe: xe device instance + * + * The caller must drain the common device I/O gate before calling this + * function. Remove all tracked VRAM mappings so later faults map the + * per-BO dummy page. + */ +void xe_bo_wedged_invalidate_mmaps(struct xe_device *xe) +{ + struct xe_bo *bo, *next; + + mutex_lock(&xe->mem_access.vram_userfault.lock); + list_for_each_entry_safe(bo, next, + &xe->mem_access.vram_userfault.list, + vram_userfault_link) + xe_bo_runtime_pm_release_mmap_offset(bo); + mutex_unlock(&xe->mem_access.vram_userfault.lock); +} + #if IS_ENABLED(CONFIG_DRM_XE_KUNIT_TEST) #include "tests/xe_bo.c" #endif diff --git a/drivers/gpu/drm/xe/xe_bo.h b/drivers/gpu/drm/xe/xe_bo.h index 77b3a02e9b8e..3bd19866819c 100644 --- a/drivers/gpu/drm/xe/xe_bo.h +++ b/drivers/gpu/drm/xe/xe_bo.h @@ -453,6 +453,7 @@ int xe_gem_create_ioctl(struct drm_device *dev, void *data, int xe_gem_mmap_offset_ioctl(struct drm_device *dev, void *data, struct drm_file *file); void xe_bo_runtime_pm_release_mmap_offset(struct xe_bo *bo); +void xe_bo_wedged_invalidate_mmaps(struct xe_device *xe); int xe_bo_dumb_create(struct drm_file *file_priv, struct drm_device *dev, diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c index 4d4139fa1be4..fa025da253d5 100644 --- a/drivers/gpu/drm/xe/xe_device.c +++ b/drivers/gpu/drm/xe/xe_device.c @@ -936,6 +936,10 @@ static void xe_device_wedged_work(struct work_struct *work) unsigned long method; int err; + /* Drain active faults before invalidating VRAM mappings. */ + xe_device_io_drain(xe); + xe_bo_wedged_invalidate_mmaps(xe); + /* Report at most one recovery method per worker invocation. */ method = READ_ONCE(xe->wedged.method); if (method != READ_ONCE(xe->wedged.reported_method)) { diff --git a/drivers/gpu/drm/xe/xe_pci_error.c b/drivers/gpu/drm/xe/xe_pci_error.c index 6606e2457503..ea55ce8114fa 100644 --- a/drivers/gpu/drm/xe/xe_pci_error.c +++ b/drivers/gpu/drm/xe/xe_pci_error.c @@ -5,6 +5,7 @@ #include <linux/pci.h> +#include "xe_bo.h" #include "xe_device.h" #include "xe_ggtt.h" #include "xe_gt.h" @@ -40,6 +41,9 @@ static void prepare_device_for_reset(struct pci_dev *pdev) */ xe_device_io_drain(xe); + /* Remove existing VRAM CPU mappings before disabling PCI. */ + xe_bo_wedged_invalidate_mmaps(xe); + pci_disable_device(pdev); } -- 2.43.0
