> Hi Gerd,
> 
> I've been seeing a regression on Nouveau with recent linux-next releases
> and git bisect points at this commit as the first bad one. If I revert
> it (there's a tiny conflict with a patch that was merged subsequently),
> things are back to normal.
> 
> I think the reason for this issue is that Nouveau doesn't use GEM
> objects for all buffer objects,

That shouldn't be a problem ...

> and even when it uses GEM objects, the
> code will not initialize the GEM object until after the buffer objects
> and the backing TTM objects have been created.

... but the initialization order is.

ttm_bo_uses_embedded_gem_object() assumes gem gets initialized first.

drm_gem_object_init() init calling drm_vma_node_reset() again is
probably the root cause for the breakage.

> I tried to fix that by making sure drm_gem_object_init() gets called by
> Nouveau before ttm_bo_init(), but the changes are fairly involved and I
> was unable to get the GEM reference counting right. I can look into the
> proper fix some more, but it might be worth reverting this patch for
> now to get Nouveau working again.

Changing the order doesn't look hard.  Patch attached (untested, have no
test hardware).  But maybe I missed some detail ...

The other patch attached works around the issue with a flag, to avoid
drm_vma_node_reset() being called twice.

cheers,
  Gerd

>From af43f933533140e2df58176a68df0c60ba082273 Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kra...@redhat.com>
Date: Wed, 14 Aug 2019 07:23:31 +0200
Subject: [PATCH 1/2] try unbreak nouveau #1

---
 include/drm/drm_gem.h        | 11 +++++++++++
 drivers/gpu/drm/drm_gem.c    |  6 ++++--
 drivers/gpu/drm/ttm/ttm_bo.c |  3 ++-
 3 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h
index ae693c0666cd..24e8fc58a3e1 100644
--- a/include/drm/drm_gem.h
+++ b/include/drm/drm_gem.h
@@ -297,6 +297,17 @@ struct drm_gem_object {
         *
         */
        const struct drm_gem_object_funcs *funcs;
+
+       /**
+        * @ttm_init: indicate ttm has initialized _resv and vma_node fields.
+        *
+        * ttm_bo_uses_embedded_gem_object() assumes gem is
+        * initialized before ttm, nouveau does it the other way
+        * around though.
+        *
+        * This is a temporary stopgap to handle that case.
+        */
+       bool ttm_init;
 };
 
 /**
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index afc38cece3f5..0a75d8cf7ac7 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -159,11 +159,13 @@ void drm_gem_private_object_init(struct drm_device *dev,
        kref_init(&obj->refcount);
        obj->handle_count = 0;
        obj->size = size;
-       reservation_object_init(&obj->_resv);
        if (!obj->resv)
                obj->resv = &obj->_resv;
 
-       drm_vma_node_reset(&obj->vma_node);
+       if (!obj->ttm_init) {
+               reservation_object_init(&obj->_resv);
+               drm_vma_node_reset(&obj->vma_node);
+       }
 }
 EXPORT_SYMBOL(drm_gem_private_object_init);
 
diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 10a861a1690c..83b389fc117e 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -160,7 +160,7 @@ static void ttm_bo_release_list(struct kref *list_kref)
        ttm_tt_destroy(bo->ttm);
        atomic_dec(&bo->bdev->glob->bo_count);
        dma_fence_put(bo->moving);
-       if (!ttm_bo_uses_embedded_gem_object(bo))
+       if (bo->base.ttm_init)
                reservation_object_fini(&bo->base._resv);
        mutex_destroy(&bo->wu_mutex);
        bo->destroy(bo);
@@ -1344,6 +1344,7 @@ int ttm_bo_init_reserved(struct ttm_bo_device *bdev,
                 */
                reservation_object_init(&bo->base._resv);
                drm_vma_node_reset(&bo->base.vma_node);
+               bo->base.ttm_init = true;
        }
        atomic_inc(&bo->bdev->glob->bo_count);
 
-- 
2.18.1

>From 3e36d5819ed5330068340e78c7a1bf35451b1dad Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kra...@redhat.com>
Date: Wed, 14 Aug 2019 07:41:05 +0200
Subject: [PATCH 2/2] try unbreak nouveau #2

---
 drivers/gpu/drm/nouveau/nouveau_bo.h    |  4 ++--
 drivers/gpu/drm/nouveau/dispnv04/crtc.c |  2 +-
 drivers/gpu/drm/nouveau/dispnv50/disp.c |  2 +-
 drivers/gpu/drm/nouveau/nouveau_bo.c    | 11 ++++++++++-
 drivers/gpu/drm/nouveau/nouveau_chan.c  |  2 +-
 drivers/gpu/drm/nouveau/nouveau_dmem.c  |  2 +-
 drivers/gpu/drm/nouveau/nouveau_gem.c   | 10 +---------
 drivers/gpu/drm/nouveau/nouveau_prime.c | 10 +---------
 drivers/gpu/drm/nouveau/nv17_fence.c    |  2 +-
 drivers/gpu/drm/nouveau/nv50_fence.c    |  2 +-
 drivers/gpu/drm/nouveau/nv84_fence.c    |  2 +-
 11 files changed, 21 insertions(+), 28 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.h 
b/drivers/gpu/drm/nouveau/nouveau_bo.h
index d675efe8e7f9..4c268f299226 100644
--- a/drivers/gpu/drm/nouveau/nouveau_bo.h
+++ b/drivers/gpu/drm/nouveau/nouveau_bo.h
@@ -73,7 +73,7 @@ extern struct ttm_bo_driver nouveau_bo_driver;
 void nouveau_bo_move_init(struct nouveau_drm *);
 int  nouveau_bo_new(struct nouveau_cli *, u64 size, int align, u32 flags,
                    u32 tile_mode, u32 tile_flags, struct sg_table *sg,
-                   struct reservation_object *robj,
+                   struct reservation_object *robj, bool gem_init,
                    struct nouveau_bo **);
 int  nouveau_bo_pin(struct nouveau_bo *, u32 flags, bool contig);
 int  nouveau_bo_unpin(struct nouveau_bo *);
@@ -115,7 +115,7 @@ nouveau_bo_new_pin_map(struct nouveau_cli *cli, u64 size, 
int align, u32 flags,
                       struct nouveau_bo **pnvbo)
 {
        int ret = nouveau_bo_new(cli, size, align, flags,
-                                0, 0, NULL, NULL, pnvbo);
+                                0, 0, NULL, NULL, false, pnvbo);
        if (ret == 0) {
                ret = nouveau_bo_pin(*pnvbo, flags, true);
                if (ret == 0) {
diff --git a/drivers/gpu/drm/nouveau/dispnv04/crtc.c 
b/drivers/gpu/drm/nouveau/dispnv04/crtc.c
index f22f01020625..5640f5e45c11 100644
--- a/drivers/gpu/drm/nouveau/dispnv04/crtc.c
+++ b/drivers/gpu/drm/nouveau/dispnv04/crtc.c
@@ -1366,7 +1366,7 @@ nv04_crtc_create(struct drm_device *dev, int crtc_num)
 
        ret = nouveau_bo_new(&nouveau_drm(dev)->client, 64*64*4, 0x100,
                             TTM_PL_FLAG_VRAM, 0, 0x0000, NULL, NULL,
-                            &nv_crtc->cursor.nvbo);
+                            false, &nv_crtc->cursor.nvbo);
        if (!ret) {
                ret = nouveau_bo_pin(nv_crtc->cursor.nvbo, TTM_PL_FLAG_VRAM, 
false);
                if (!ret) {
diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c 
b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index 8497768f1b41..047c0166f823 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -2319,7 +2319,7 @@ nv50_display_create(struct drm_device *dev)
 
        /* small shared memory area we use for notifiers and semaphores */
        ret = nouveau_bo_new(&drm->client, 4096, 0x1000, TTM_PL_FLAG_VRAM,
-                            0, 0x0000, NULL, NULL, &disp->sync);
+                            0, 0x0000, NULL, NULL, false, &disp->sync);
        if (!ret) {
                ret = nouveau_bo_pin(disp->sync, TTM_PL_FLAG_VRAM, true);
                if (!ret) {
diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c 
b/drivers/gpu/drm/nouveau/nouveau_bo.c
index 99e391be9370..b1b67a427a98 100644
--- a/drivers/gpu/drm/nouveau/nouveau_bo.c
+++ b/drivers/gpu/drm/nouveau/nouveau_bo.c
@@ -189,7 +189,7 @@ int
 nouveau_bo_new(struct nouveau_cli *cli, u64 size, int align,
               uint32_t flags, uint32_t tile_mode, uint32_t tile_flags,
               struct sg_table *sg, struct reservation_object *robj,
-              struct nouveau_bo **pnvbo)
+              bool gem_init, struct nouveau_bo **pnvbo)
 {
        struct nouveau_drm *drm = cli->drm;
        struct nouveau_bo *nvbo;
@@ -295,6 +295,15 @@ nouveau_bo_new(struct nouveau_cli *cli, u64 size, int 
align,
        acc_size = ttm_bo_dma_acc_size(&drm->ttm.bdev, size,
                                       sizeof(struct nouveau_bo));
 
+       if (gem_init) {
+               /* Initialize the embedded gem-object. */
+               ret = drm_gem_object_init(drm->dev, &nvbo->bo.base, size);
+               if (ret) {
+                       kfree(nvbo);
+                       return -ENOMEM;
+               }
+       }
+
        ret = ttm_bo_init(&drm->ttm.bdev, &nvbo->bo, size,
                          type, &nvbo->placement,
                          align >> PAGE_SHIFT, false, acc_size, sg,
diff --git a/drivers/gpu/drm/nouveau/nouveau_chan.c 
b/drivers/gpu/drm/nouveau/nouveau_chan.c
index 282fd90b65e1..fedf3239b2e4 100644
--- a/drivers/gpu/drm/nouveau/nouveau_chan.c
+++ b/drivers/gpu/drm/nouveau/nouveau_chan.c
@@ -144,7 +144,7 @@ nouveau_channel_prep(struct nouveau_drm *drm, struct 
nvif_device *device,
                target = TTM_PL_FLAG_VRAM;
 
        ret = nouveau_bo_new(cli, size, 0, target, 0, 0, NULL, NULL,
-                           &chan->push.buffer);
+                            false, &chan->push.buffer);
        if (ret == 0) {
                ret = nouveau_bo_pin(chan->push.buffer, target, false);
                if (ret == 0)
diff --git a/drivers/gpu/drm/nouveau/nouveau_dmem.c 
b/drivers/gpu/drm/nouveau/nouveau_dmem.c
index 1333220787a1..4090ba54bbdd 100644
--- a/drivers/gpu/drm/nouveau/nouveau_dmem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_dmem.c
@@ -314,7 +314,7 @@ nouveau_dmem_chunk_alloc(struct nouveau_drm *drm)
 
        ret = nouveau_bo_new(&drm->client, DMEM_CHUNK_SIZE, 0,
                             TTM_PL_FLAG_VRAM, 0, 0, NULL, NULL,
-                            &chunk->bo);
+                            false, &chunk->bo);
        if (ret)
                goto out;
 
diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c 
b/drivers/gpu/drm/nouveau/nouveau_gem.c
index c7368aa0bdec..1993f2c90e4c 100644
--- a/drivers/gpu/drm/nouveau/nouveau_gem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_gem.c
@@ -189,7 +189,7 @@ nouveau_gem_new(struct nouveau_cli *cli, u64 size, int 
align, uint32_t domain,
                flags |= TTM_PL_FLAG_UNCACHED;
 
        ret = nouveau_bo_new(cli, size, align, flags, tile_mode,
-                            tile_flags, NULL, NULL, pnvbo);
+                            tile_flags, NULL, NULL, true, pnvbo);
        if (ret)
                return ret;
        nvbo = *pnvbo;
@@ -203,14 +203,6 @@ nouveau_gem_new(struct nouveau_cli *cli, u64 size, int 
align, uint32_t domain,
        if (drm->client.device.info.family >= NV_DEVICE_INFO_V0_TESLA)
                nvbo->valid_domains &= domain;
 
-       /* Initialize the embedded gem-object. We return a single gem-reference
-        * to the caller, instead of a normal nouveau_bo ttm reference. */
-       ret = drm_gem_object_init(drm->dev, &nvbo->bo.base, nvbo->bo.mem.size);
-       if (ret) {
-               nouveau_bo_ref(NULL, pnvbo);
-               return -ENOMEM;
-       }
-
        nvbo->bo.persistent_swap_storage = nvbo->bo.base.filp;
        return 0;
 }
diff --git a/drivers/gpu/drm/nouveau/nouveau_prime.c 
b/drivers/gpu/drm/nouveau/nouveau_prime.c
index e86ad7ae622b..db1ec2d0d4c9 100644
--- a/drivers/gpu/drm/nouveau/nouveau_prime.c
+++ b/drivers/gpu/drm/nouveau/nouveau_prime.c
@@ -70,21 +70,13 @@ struct drm_gem_object 
*nouveau_gem_prime_import_sg_table(struct drm_device *dev,
 
        reservation_object_lock(robj, NULL);
        ret = nouveau_bo_new(&drm->client, attach->dmabuf->size, 0, flags, 0, 0,
-                            sg, robj, &nvbo);
+                            sg, robj, true, &nvbo);
        reservation_object_unlock(robj);
        if (ret)
                return ERR_PTR(ret);
 
        nvbo->valid_domains = NOUVEAU_GEM_DOMAIN_GART;
 
-       /* Initialize the embedded gem-object. We return a single gem-reference
-        * to the caller, instead of a normal nouveau_bo ttm reference. */
-       ret = drm_gem_object_init(dev, &nvbo->bo.base, nvbo->bo.mem.size);
-       if (ret) {
-               nouveau_bo_ref(NULL, &nvbo);
-               return ERR_PTR(-ENOMEM);
-       }
-
        return &nvbo->bo.base;
 }
 
diff --git a/drivers/gpu/drm/nouveau/nv17_fence.c 
b/drivers/gpu/drm/nouveau/nv17_fence.c
index 5d613d43b84d..6c589d0b847c 100644
--- a/drivers/gpu/drm/nouveau/nv17_fence.c
+++ b/drivers/gpu/drm/nouveau/nv17_fence.c
@@ -128,7 +128,7 @@ nv17_fence_create(struct nouveau_drm *drm)
        spin_lock_init(&priv->lock);
 
        ret = nouveau_bo_new(&drm->client, 4096, 0x1000, TTM_PL_FLAG_VRAM,
-                            0, 0x0000, NULL, NULL, &priv->bo);
+                            0, 0x0000, NULL, NULL, false, &priv->bo);
        if (!ret) {
                ret = nouveau_bo_pin(priv->bo, TTM_PL_FLAG_VRAM, false);
                if (!ret) {
diff --git a/drivers/gpu/drm/nouveau/nv50_fence.c 
b/drivers/gpu/drm/nouveau/nv50_fence.c
index a00ecc3de053..17910bfca099 100644
--- a/drivers/gpu/drm/nouveau/nv50_fence.c
+++ b/drivers/gpu/drm/nouveau/nv50_fence.c
@@ -81,7 +81,7 @@ nv50_fence_create(struct nouveau_drm *drm)
        spin_lock_init(&priv->lock);
 
        ret = nouveau_bo_new(&drm->client, 4096, 0x1000, TTM_PL_FLAG_VRAM,
-                            0, 0x0000, NULL, NULL, &priv->bo);
+                            0, 0x0000, NULL, NULL, false, &priv->bo);
        if (!ret) {
                ret = nouveau_bo_pin(priv->bo, TTM_PL_FLAG_VRAM, false);
                if (!ret) {
diff --git a/drivers/gpu/drm/nouveau/nv84_fence.c 
b/drivers/gpu/drm/nouveau/nv84_fence.c
index f07da00f285f..fecdb036521e 100644
--- a/drivers/gpu/drm/nouveau/nv84_fence.c
+++ b/drivers/gpu/drm/nouveau/nv84_fence.c
@@ -204,7 +204,7 @@ nv84_fence_create(struct nouveau_drm *drm)
                          */
                         TTM_PL_FLAG_TT | TTM_PL_FLAG_UNCACHED;
        ret = nouveau_bo_new(&drm->client, 16 * drm->chan.nr, 0,
-                            domain, 0, 0, NULL, NULL, &priv->bo);
+                            domain, 0, 0, NULL, NULL, false, &priv->bo);
        if (ret == 0) {
                ret = nouveau_bo_pin(priv->bo, domain, false);
                if (ret == 0) {
-- 
2.18.1

_______________________________________________
Spice-devel mailing list
Spice-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/spice-devel

Reply via email to