From 0cf72e0ad352a3d9ec8e1b6822ab5601149caaaa Mon Sep 17 00:00:00 2001
From: Matthew Auld <matthew.auld@intel.com>
Date: Thu, 6 Jan 2022 17:49:08 +0000
Subject: drm/i915/ttm: only fault WILLNEED objects
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Git-commit: 03ee5956781b2245b1c77334ecdea6386fd3bfba
Patch-mainline: v5.17-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

Don't attempt to fault and re-populate purged objects. By some fluke
this passes the dontneed-after-mmap IGT, but for the wrong reasons.

Fixes: cf3e3e86d779 ("drm/i915: Use ttm mmap handling for ttm bo's.")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220106174910.280616-2-matthew.auld@intel.com
(cherry picked from commit f3cb4a2de5410147b53e53416a3af0ffe26b5f4e)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
index 923cc7ad8d70..8d61d4538a64 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
@@ -883,6 +883,11 @@ static vm_fault_t vm_fault_ttm(struct vm_fault *vmf)
 	if (ret)
 		return ret;
 
+	if (obj->mm.madv != I915_MADV_WILLNEED) {
+		dma_resv_unlock(bo->base.resv);
+		return VM_FAULT_SIGBUS;
+	}
+
 	if (drm_dev_enter(dev, &idx)) {
 		ret = ttm_bo_vm_fault_reserved(vmf, vmf->vma->vm_page_prot,
 					       TTM_BO_VM_NUM_PREFAULT);
-- 
2.38.1