[virglrenderer-devel] Strange graphical glitches under virgl.

[Lepton Wu]

FYI, I have a CL which is using another way to do copy and it seems it
fixes this bug for me also, but I still don't know the bug in  the
current copy_int code. Will continue to work on it.

This is my patch which "fix" this issue for me:

diff --git a/src/vrend_renderer.c b/src/vrend_renderer.c
index 5f8ff23..70b191b 100644
--- a/src/vrend_renderer.c
+++ b/src/vrend_renderer.c
@@ -6019,6 +6019,31 @@ void vrend_renderer_resource_copy_region(struct
vrend_context *ctx,

 }

+static void simple_copy(struct vrend_context *ctx,
+ struct vrend_resource *src_res,
+ struct vrend_resource *dst_res,
+ const struct pipe_blit_info* info) {
+   GLint read_fbo = 0;
+   glGetIntegerv(GL_READ_FRAMEBUFFER_BINDING, &read_fbo);
+   glBindFramebuffer(GL_READ_FRAMEBUFFER, ctx->sub->blit_fb_ids[0]);
+   glFramebufferTexture2DEXT(GL_READ_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT,
+             GL_TEXTURE_2D, 0, 0);
+   glFramebufferTexture2DEXT(GL_READ_FRAMEBUFFER,
GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, src_res->id, 0);
+   GLint current_2d = 0;
+   glGetIntegerv(GL_TEXTURE_BINDING_2D, &current_2d);
+   glBindTexture(GL_TEXTURE_2D, dst_res->id);
+   glCopyTexSubImage2D(GL_TEXTURE_2D, 0,
+   info->dst.box.x,
+   info->dst.box.y,
+   info->src.box.x,
+   info->src.box.y,
+   info->src.box.width,
+   info->src.box.height);
+    glBindTexture(GL_TEXTURE_2D, current_2d);
+    glFramebufferTexture2DEXT(GL_READ_FRAMEBUFFER,
GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
+    glBindFramebuffer(GL_READ_FRAMEBUFFER, read_fbo);
+}
+
 static void vrend_renderer_blit_int(struct vrend_context *ctx,
                                     struct vrend_resource *src_res,
                                     struct vrend_resource *dst_res,
@@ -6085,6 +6110,22 @@ static void vrend_renderer_blit_int(struct
vrend_context *ctx,
       return;
    }

+   if (filter == GL_NEAREST &&
+       src_res->base.format == dst_res->base.format &&
+       src_res->base.format == PIPE_FORMAT_B8G8R8A8_UNORM &&
+       info->mask == PIPE_MASK_RGBA &&
+       info->src.box.width == info->dst.box.width &&
+       info->src.box.height == info->dst.box.height &&
+       info->src.box.x == info->dst.box.x &&
+       info->src.box.y == info->dst.box.y &&
+       info->src.box.depth == info->dst.box.depth &&
+       info->src.box.depth == 1 &&
+       info->src.box.z == info->dst.box.z &&
+       info->src.box.z == 0 ) {
+     simple_copy(ctx, src_res, dst_res, info);
+     return;
+   }
+
    if (info->mask & PIPE_MASK_Z)
       glmask |= GL_DEPTH_BUFFER_BIT;
    if (info->mask & PIPE_MASK_S)


On Mon, Jul 23, 2018 at 2:13 PM Lepton Wu <lepton at chromium.org> wrote:
>
> Hi Gert,
> Thanks for trying to reproduce it. I really appreciate your help on this issue.
>
> FYI, I just tried on 2 different linux desktop with different host gpu
> and I can reproduce on both machines. Since you can't reproduce it,
> this could be
> something related with  my guest. Here is my setup:
>
> 1. Both desktop runs Debian stretch.
> 2. One desktop come with amd rx480 gpu and I install amd-gpu-pro
> driver on it. Another desktop just come with integrated intel gpu
> (intel G4600 CPU) and I am just using default
> mesa driver come with debian distribution.
> 3. I just install libepoxy-dev from debian official repo which is
> version 1.3.1-2
> 4. For virglrenderder, I just get code from git and then do this :
> "git checkout -b buggy be3b107", this is the last commit before the
> glCopyimagesubdata change.
> 5. For qemu, I compile it like this:
>     export PKG_CONFIG_PATH=$HOME/virgl/lib/pkgconfig
>      ./configure --target-list=x86_64-softmmu --disable-gtk
> --enable-virglrenderer --audio-drv-list=pa
> 6. For guest, as I said before, it's a chrome os guest. It can be get like this:
>     wget https://storage.googleapis.com/chrome_os_emulator/sysimg_67-10575.63.0.zip
>     unzip -x sysimg_67-10575.63.0.zip
>     qemu-img convert -O raw x86/userdata.img rawdata.img
>     cat x86/system.img rawdata.img x86/vendor.img > disk.img
>  7. I am running qemu with the following flags:
>      qemu-img create -f qcow2 -b disk.img disk.img.qcow2
>      x86_64-softmmu/qemu-system-x86_64 -soundhw hda -enable-kvm -m
> 4096 -net nic,model=virtio -net user,hostfwd=tcp:127.0.0.1:9222-:22
> -device virtio-vga -display sdl,gl=on -device usb-ehci -device
> usb-tablet -show-cursor -smp 4 disk.img.qcow2
>
>     At the login screen,  it will ask for gmail account,  I just skip
> this step by click "More options", and then click "Guest mode".
>
> On Sun, Jul 22, 2018 at 4:35 AM Gert Wollny <gert.wollny at collabora.com> wrote:
> >
> > Am Freitag, den 20.07.2018, 14:12 -0700 schrieb Lepton Wu:
> > > Hi,
> > >
> > > I have an issue which I recorded a video  to show the bug:
> > > https://youtu.be/ECGDCMAOTxs
> > > You can see, sometimes, there is a "wrong block" of rendering. It's
> > > always some kind of rectangle somewhere.
> > > A strange part is: I've never seen this kind of issue if I am running
> > > 3D android games under virgl. Games always
> > > running fine. But for Chrome, it sometimes come with this kind of
> > > weird graphics.
> >
> > I was not able to reproduce the issue.
> > I used the latest master of virglrenderer and mesa on an Intel Kabylake
> >  host, and disabled the copy_image copy path via
> >   MESA_EXTENSION_OVERRIDE=-GL_ARGB_copy_image
> > so that virglrenderer could not use this shortcut for copy-blits.
> >
> > Inside the guest I used Ubuntu bionic with the latest updates and a PPA
> >  kernel: Linux version 4.16.0-041600-generic (kernel at kathleen)
> > (4.16 is needed to support report host caps v2 to the guest).
> >
> > I tried both blackbox and a gnome-session with chromium-browser and I
> > didn't seen any of these artifacts. What is actually the desktop
> > environment that you were using?
> >
> > best,
> > Gert
> >
> >
> >
> >