On Fri, May 10, 2013 at 10:44:05AM +0300, Ander Conselvan de Oliveira wrote: > On 05/08/2013 11:50 PM, Jonas Ådahl wrote: > >On Tue, Apr 23, 2013 at 3:54 PM, Ander Conselvan de Oliveira > ><ander.conselvan.de.olive...@intel.com> wrote: > >>Linux kernel 3.8 shipped with a bug in the prime fd passing code that > >>makes it unreliable. As of this writing, it seems unlikely that 3.9 > >>will contain the fix for the issue. > >> > >>This patch disable prime support when running on top of those kernels, > >>in order to prevent unexpected behavior when running a Wayland > >>compositor. > >> > >>Commit be8a42ae60addd8b6092535c11b42d099d6470ec in Linus tree introduces > >>the problem, which can be fixed by the patch below (not upstream yet): > >>http://lists.freedesktop.org/archives/dri-devel/2013-April/037716.html > >>--- > >> src/egl/drivers/dri2/egl_dri2.c | 36 > >> +++++++++++++++++++++++++++++++++++- > >> 1 file changed, 35 insertions(+), 1 deletion(-) > >> > >>diff --git a/src/egl/drivers/dri2/egl_dri2.c > >>b/src/egl/drivers/dri2/egl_dri2.c > >>index 06a21d7..13b9107 100644 > >>--- a/src/egl/drivers/dri2/egl_dri2.c > >>+++ b/src/egl/drivers/dri2/egl_dri2.c > >>@@ -38,6 +38,7 @@ > >> #include <GL/internal/dri_interface.h> > >> #include <sys/types.h> > >> #include <sys/stat.h> > >>+#include <sys/utsname.h> > >> > >> #include "egl_dri2.h" > >> > >>@@ -1557,6 +1558,38 @@ static struct wayland_drm_callbacks wl_drm_callbacks > >>= { > >> }; > >> > >> static EGLBoolean > >>+kernel_prime_support_not_buggy() > >>+{ > >>+ struct utsname un; > >>+ > >>+ /* Linux kernel 3.8 shipped with a bug in the prime fd passing code that > >>+ * makes it unreliable. As of this writing, it seems unlikely that 3.9 > >>+ * will contain the fix for the issue. Disable prime support when > >>running > >>+ * on top of those kernels, in order to prevent unexpected behavior when > >>+ * running a Wayland compositor. > >>+ * > >>+ * Commit be8a42ae60addd8b6092535c11b42d099d6470ec in Linus tree > >>introduces > >>+ * the problem, which can be fixed by the patch below (not upstream > >>yet): > >>+ * > >>http://lists.freedesktop.org/archives/dri-devel/2013-April/037716.html > >>+ */ > >>+ if (uname(&un) == -1) { > >>+ _eglLog(_EGL_INFO, > >>+ "DRI2: wayland prime support disabled: unknown kernel > >>version"); > >>+ return EGL_FALSE; > >>+ } > >>+ > >>+ if (strncmp(un.sysname, "Linux", strlen("Linux")) == 0 && > >>+ (strncmp(un.release, "3.8.", strlen("3.8.")) == 0 || > >>+ strncmp(un.release, "3.9.", strlen("3.9.")) == 0)) { > > > >I think if we should test against kernel releases we can disable for > >anything older than the first release that has the fix as it doesn't > >seem to work on older versions either. At least in my case I get what > >looks like the same issue when prime support enabled when running > >kernel version 3.5. > > Your distro probably picked up the patch that introduces the bug. > But anyway, I think this patch should just be dropped. It doesn't > really solve the issue. > > There's no Mesa release with prime support yet, so I guess we should > just disable it for now, until things are solved on the kernel side.
Things are solved on the kernel side now I think, and prime fixes are trickling down to all stable releases atm. So I don't think you need any workarounds and we can just enable prime buffer passing in the next mesa release. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
