lfdevs · lfdevs · Jul 6, 2026 · Jul 9, 2026 · lfdevs · lfdevs
diff --git a/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch b/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch
@@ -0,0 +1,142 @@
+From e910fc1dda09b916e190f5f8645abae5b6ebfda3 Mon Sep 17 00:00:00 2001
+From: superturtlee <160681686+superturtlee@users.noreply.github.com>
+Date: Mon, 6 Jul 2026 09:56:24 +0800
+Subject: [PATCH] xwayland: support kgsl dmabuf v3 fallback paths
+
+Allow glamor to initialize with linux-dmabuf v3 when wl_drm and dmabuf
+feedback are unavailable, fall back to a configurable GBM render node, and
+handle implicit or bogus linear modifiers used by kgsl/freedreno stacks.
+
+Based-on-patch: https://github.com/superturtlee/anland/blob/1.11/producers/kde/ubuntu2604/xwayland.patch
+
+Co-authored-by: lfdevs <lfdevs@lfdevs.com>
+---
+ hw/xwayland/xwayland-glamor-gbm.c | 65 ++++++++++++++++++++++---------
+ hw/xwayland/xwayland-glamor.c | 9 +++++
+ 2 files changed, 56 insertions(+), 18 deletions(-)
+
+diff --git a/hw/xwayland/xwayland-glamor-gbm.c b/hw/xwayland/xwayland-glamor-gbm.c
+index 05668b8e9..5ce344b3c 100644
+--- a/hw/xwayland/xwayland-glamor-gbm.c
++++ b/hw/xwayland/xwayland-glamor-gbm.c
+@@ -33,6 +33,7 @@
+ #include <fcntl.h>
+ #include <errno.h>
+ #include <poll.h>
++#include <stdlib.h>
+ #ifdef DRI3
+ #include <sys/eventfd.h>
+ #endif /* DRI3 */
+@@ -590,8 +591,17 @@ xwl_glamor_pixmap_get_wl_buffer(PixmapPtr pixmap)
+ return NULL;
+ }
+
++ /* An implicit-modifier buffer (DRM_FORMAT_MOD_INVALID) is never listed in
++ * the compositor's advertised modifier set, so the regular support check
++ * fails. On the kgsl/turnip stack - where the buffer is allocated on the
++ * display node but composited by turnip - that left both the dmabuf and
++ * the (absent) wl_drm path unusable, so no wl_buffer was created and the
++ * X11 window stayed black. Per the linux-dmabuf protocol, INVALID means
++ * "let the compositor infer the layout", so submit it through the dmabuf
++ * path directly instead of rejecting it. */
+ if (xwl_screen->dmabuf &&
+- xwl_glamor_is_modifier_supported(xwl_screen, format, modifier)) {
++ (modifier == DRM_FORMAT_MOD_INVALID ||
++ xwl_glamor_is_modifier_supported(xwl_screen, format, modifier))) {
+ struct zwp_linux_buffer_params_v1 *params;
+
+ params = zwp_linux_dmabuf_v1_create_params(xwl_screen->dmabuf);
+@@ -773,6 +783,15 @@ glamor_pixmap_from_fds(ScreenPtr screen, CARD8 num_fds, const int *fds,
+ strides[0] < width * bpp / 8)
+ goto error;
+
++ /* Some freedreno/kgsl mesa builds (the on-device dev tree) rewrite a
++ * LINEAR modifier (0) to a bogus 1274 (0x4FA) in the loader_dri3
++ * pixmap_from_buffers path. 1274 is not a valid DRM modifier, so the
++ * gbm_bo_import() below rejects it and the X11 GL client gets BadAlloc
++ * (dri3_alloc_render_buffer -> pixmap_from_buffer[s] failed -> segfault).
++ * The buffer is really linear, so map the bogus value back to LINEAR. */
++ if (modifier == 1274ULL)
++ modifier = DRM_FORMAT_MOD_LINEAR;
++
+ if (xwl_gbm->dmabuf_capable && modifier != DRM_FORMAT_MOD_INVALID) {
+ #ifdef GBM_BO_WITH_MODIFIERS
+ struct gbm_import_fd_modifier_data data;
+@@ -1665,27 +1684,37 @@ static Bool
+ xwl_glamor_gbm_init_main_dev(struct xwl_screen *xwl_screen)
+ {
+ struct xwl_gbm_private *xwl_gbm = xwl_gbm_get(xwl_screen);
+- drmDevice *main_dev;
+-
+- while (!xwl_screen->default_feedback.feedback_done) {
+- if (wl_display_dispatch(xwl_screen->display) < 0) {
+- ErrorF("Failed to dispatch Wayland display\n");
+- return FALSE;
++ drmDevice *main_dev = NULL;
++
++ /* linux-dmabuf feedback (and thus a main device) only exists from protocol
++ * version 4. On the kgsl/turnip stack the compositor only speaks v3, so
++ * there is no feedback to wait for - skip the wait and go straight to the
++ * fallback render node below instead of blocking forever on feedback_done. */
++ if (xwl_screen->dmabuf_protocol_version >= 4) {
++ while (!xwl_screen->default_feedback.feedback_done) {
++ if (wl_display_dispatch(xwl_screen->display) < 0) {
++ ErrorF("Failed to dispatch Wayland display\n");
++ return FALSE;
++ }
+ }
++ main_dev = xwl_screen->default_feedback.main_dev;
+ }
+
+- main_dev = xwl_screen->default_feedback.main_dev;
+- if (!main_dev) {
+- ErrorF("No main linux-dmabuf device advertised by compositor\n");
+- return FALSE;
+- }
+-
+- if (!(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
+- ErrorF("Main linux-dmabuf device has no render node\n");
+- return FALSE;
++ /* On the kgsl-backed turnip stack the compositor advertises no usable DRM
++ * render node (the GPU is exposed through kgsl, not a standard DRM node),
++ * so main_dev is NULL or render-node-less. Rather than dereferencing NULL
++ * (-> crash) or bailing out, fall back to a default render node, which the
++ * patched freedreno mesa redirects to /dev/kgsl-3d0 for native GL. */
++ if (!main_dev || !(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
++ const char *fallback = getenv("XWAYLAND_GBM_DEVICE");
++ if (!fallback)
++ fallback = "/dev/dri/renderD128";
++ ErrorF("No usable linux-dmabuf main device, falling back to %s\n",
++ fallback);
++ xwl_gbm->device_name = strdup(fallback);
++ } else {
++ xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ }
+-
+- xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ if (!xwl_gbm->device_name) {
+ return FALSE;
+ }
+diff --git a/hw/xwayland/xwayland-glamor.c b/hw/xwayland/xwayland-glamor.c
+index 88ced5da0..35d1e0391 100644
+--- a/hw/xwayland/xwayland-glamor.c
++++ b/hw/xwayland/xwayland-glamor.c
+@@ -123,6 +123,15 @@ xwl_glamor_has_wl_interfaces(struct xwl_screen *xwl_screen)
+ {
+ if (!xwl_glamor_has_wl_drm(xwl_screen) &&
+ xwl_screen->dmabuf_protocol_version < 4) {
++ /* No wl_drm and no linux-dmabuf feedback (v4). On the kgsl/turnip stack
++ * the compositor exposes neither (the GPU lives behind /dev/kgsl-3d0,
++ * not a DRM render node, so there is no main device to advertise), but
++ * it does speak linux-dmabuf v3. We can still bring glamor up by opening
++ * a fallback render node directly (see xwl_glamor_gbm_init_main_dev) and
++ * submitting buffers over dmabuf v3, so keep glamor available as long as
++ * v3 is present. */
++ if (xwl_screen->dmabuf_protocol_version >= 3)
++ return TRUE;
+ LogMessageVerb(X_INFO, 3, "glamor: 'wl_drm' not supported and linux-dmabuf v4 not supported\n");
+ return FALSE;
+ }
+-- 
+2.47.3
+
diff --git a/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch b/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch
@@ -0,0 +1,142 @@
+From e910fc1dda09b916e190f5f8645abae5b6ebfda3 Mon Sep 17 00:00:00 2001
+From: superturtlee <160681686+superturtlee@users.noreply.github.com>
+Date: Mon, 6 Jul 2026 09:56:24 +0800
+Subject: [PATCH] xwayland: support kgsl dmabuf v3 fallback paths
+
+Allow glamor to initialize with linux-dmabuf v3 when wl_drm and dmabuf
+feedback are unavailable, fall back to a configurable GBM render node, and
+handle implicit or bogus linear modifiers used by kgsl/freedreno stacks.
+
+Based-on-patch: https://github.com/superturtlee/anland/blob/1.11/producers/kde/ubuntu2604/xwayland.patch
+
+Co-authored-by: lfdevs <lfdevs@lfdevs.com>
+---
+ hw/xwayland/xwayland-glamor-gbm.c | 65 ++++++++++++++++++++++---------
+ hw/xwayland/xwayland-glamor.c | 9 +++++
+ 2 files changed, 56 insertions(+), 18 deletions(-)
+
+diff --git a/hw/xwayland/xwayland-glamor-gbm.c b/hw/xwayland/xwayland-glamor-gbm.c
+index 05668b8e9..5ce344b3c 100644
+--- a/hw/xwayland/xwayland-glamor-gbm.c
++++ b/hw/xwayland/xwayland-glamor-gbm.c
+@@ -33,6 +33,7 @@
+ #include <fcntl.h>
+ #include <errno.h>
+ #include <poll.h>
++#include <stdlib.h>
+ #ifdef DRI3
+ #include <sys/eventfd.h>
+ #endif /* DRI3 */
+@@ -590,8 +591,17 @@ xwl_glamor_pixmap_get_wl_buffer(PixmapPtr pixmap)
+ return NULL;
+ }
+
++ /* An implicit-modifier buffer (DRM_FORMAT_MOD_INVALID) is never listed in
++ * the compositor's advertised modifier set, so the regular support check
++ * fails. On the kgsl/turnip stack - where the buffer is allocated on the
++ * display node but composited by turnip - that left both the dmabuf and
++ * the (absent) wl_drm path unusable, so no wl_buffer was created and the
++ * X11 window stayed black. Per the linux-dmabuf protocol, INVALID means
++ * "let the compositor infer the layout", so submit it through the dmabuf
++ * path directly instead of rejecting it. */
+ if (xwl_screen->dmabuf &&
+- xwl_glamor_is_modifier_supported(xwl_screen, format, modifier)) {
++ (modifier == DRM_FORMAT_MOD_INVALID ||
++ xwl_glamor_is_modifier_supported(xwl_screen, format, modifier))) {
+ struct zwp_linux_buffer_params_v1 *params;
+
+ params = zwp_linux_dmabuf_v1_create_params(xwl_screen->dmabuf);
+@@ -773,6 +783,15 @@ glamor_pixmap_from_fds(ScreenPtr screen, CARD8 num_fds, const int *fds,
+ strides[0] < width * bpp / 8)
+ goto error;
+
++ /* Some freedreno/kgsl mesa builds (the on-device dev tree) rewrite a
++ * LINEAR modifier (0) to a bogus 1274 (0x4FA) in the loader_dri3
++ * pixmap_from_buffers path. 1274 is not a valid DRM modifier, so the
++ * gbm_bo_import() below rejects it and the X11 GL client gets BadAlloc
++ * (dri3_alloc_render_buffer -> pixmap_from_buffer[s] failed -> segfault).
++ * The buffer is really linear, so map the bogus value back to LINEAR. */
++ if (modifier == 1274ULL)
++ modifier = DRM_FORMAT_MOD_LINEAR;
++
+ if (xwl_gbm->dmabuf_capable && modifier != DRM_FORMAT_MOD_INVALID) {
+ #ifdef GBM_BO_WITH_MODIFIERS
+ struct gbm_import_fd_modifier_data data;
+@@ -1665,27 +1684,37 @@ static Bool
+ xwl_glamor_gbm_init_main_dev(struct xwl_screen *xwl_screen)
+ {
+ struct xwl_gbm_private *xwl_gbm = xwl_gbm_get(xwl_screen);
+- drmDevice *main_dev;
+-
+- while (!xwl_screen->default_feedback.feedback_done) {
+- if (wl_display_dispatch(xwl_screen->display) < 0) {
+- ErrorF("Failed to dispatch Wayland display\n");
+- return FALSE;
++ drmDevice *main_dev = NULL;
++
++ /* linux-dmabuf feedback (and thus a main device) only exists from protocol
++ * version 4. On the kgsl/turnip stack the compositor only speaks v3, so
++ * there is no feedback to wait for - skip the wait and go straight to the
++ * fallback render node below instead of blocking forever on feedback_done. */
++ if (xwl_screen->dmabuf_protocol_version >= 4) {
++ while (!xwl_screen->default_feedback.feedback_done) {
++ if (wl_display_dispatch(xwl_screen->display) < 0) {
++ ErrorF("Failed to dispatch Wayland display\n");
++ return FALSE;
++ }
+ }
++ main_dev = xwl_screen->default_feedback.main_dev;
+ }
+
+- main_dev = xwl_screen->default_feedback.main_dev;
+- if (!main_dev) {
+- ErrorF("No main linux-dmabuf device advertised by compositor\n");
+- return FALSE;
+- }
+-
+- if (!(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
+- ErrorF("Main linux-dmabuf device has no render node\n");
+- return FALSE;
++ /* On the kgsl-backed turnip stack the compositor advertises no usable DRM
++ * render node (the GPU is exposed through kgsl, not a standard DRM node),
++ * so main_dev is NULL or render-node-less. Rather than dereferencing NULL
++ * (-> crash) or bailing out, fall back to a default render node, which the
++ * patched freedreno mesa redirects to /dev/kgsl-3d0 for native GL. */
++ if (!main_dev || !(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
++ const char *fallback = getenv("XWAYLAND_GBM_DEVICE");
++ if (!fallback)
++ fallback = "/dev/dri/renderD128";
++ ErrorF("No usable linux-dmabuf main device, falling back to %s\n",
++ fallback);
++ xwl_gbm->device_name = strdup(fallback);
++ } else {
++ xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ }
+-
+- xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ if (!xwl_gbm->device_name) {
+ return FALSE;
+ }
+diff --git a/hw/xwayland/xwayland-glamor.c b/hw/xwayland/xwayland-glamor.c
+index 88ced5da0..35d1e0391 100644
+--- a/hw/xwayland/xwayland-glamor.c
++++ b/hw/xwayland/xwayland-glamor.c
+@@ -123,6 +123,15 @@ xwl_glamor_has_wl_interfaces(struct xwl_screen *xwl_screen)
+ {
+ if (!xwl_glamor_has_wl_drm(xwl_screen) &&
+ xwl_screen->dmabuf_protocol_version < 4) {
++ /* No wl_drm and no linux-dmabuf feedback (v4). On the kgsl/turnip stack
++ * the compositor exposes neither (the GPU lives behind /dev/kgsl-3d0,
++ * not a DRM render node, so there is no main device to advertise), but
++ * it does speak linux-dmabuf v3. We can still bring glamor up by opening
++ * a fallback render node directly (see xwl_glamor_gbm_init_main_dev) and
++ * submitting buffers over dmabuf v3, so keep glamor available as long as
++ * v3 is present. */
++ if (xwl_screen->dmabuf_protocol_version >= 3)
++ return TRUE;
+ LogMessageVerb(X_INFO, 3, "glamor: 'wl_drm' not supported and linux-dmabuf v4 not supported\n");
+ return FALSE;
+ }
+-- 
+2.47.3
+
diff --git a/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch b/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch
@@ -0,0 +1,142 @@
+From e910fc1dda09b916e190f5f8645abae5b6ebfda3 Mon Sep 17 00:00:00 2001
+From: superturtlee <160681686+superturtlee@users.noreply.github.com>
+Date: Mon, 6 Jul 2026 09:56:24 +0800
+Subject: [PATCH] xwayland: support kgsl dmabuf v3 fallback paths
+
+Allow glamor to initialize with linux-dmabuf v3 when wl_drm and dmabuf
+feedback are unavailable, fall back to a configurable GBM render node, and
+handle implicit or bogus linear modifiers used by kgsl/freedreno stacks.
+
+Based-on-patch: https://github.com/superturtlee/anland/blob/1.11/producers/kde/ubuntu2604/xwayland.patch
+
+Co-authored-by: lfdevs <lfdevs@lfdevs.com>
+---
+ hw/xwayland/xwayland-glamor-gbm.c | 65 ++++++++++++++++++++++---------
+ hw/xwayland/xwayland-glamor.c | 9 +++++
+ 2 files changed, 56 insertions(+), 18 deletions(-)
+
+diff --git a/hw/xwayland/xwayland-glamor-gbm.c b/hw/xwayland/xwayland-glamor-gbm.c
+index 05668b8e9..5ce344b3c 100644
+--- a/hw/xwayland/xwayland-glamor-gbm.c
++++ b/hw/xwayland/xwayland-glamor-gbm.c
+@@ -33,6 +33,7 @@
+ #include <fcntl.h>
+ #include <errno.h>
+ #include <poll.h>
++#include <stdlib.h>
+ #ifdef DRI3
+ #include <sys/eventfd.h>
+ #endif /* DRI3 */
+@@ -590,8 +591,17 @@ xwl_glamor_pixmap_get_wl_buffer(PixmapPtr pixmap)
+ return NULL;
+ }
+
++ /* An implicit-modifier buffer (DRM_FORMAT_MOD_INVALID) is never listed in
++ * the compositor's advertised modifier set, so the regular support check
++ * fails. On the kgsl/turnip stack - where the buffer is allocated on the
++ * display node but composited by turnip - that left both the dmabuf and
++ * the (absent) wl_drm path unusable, so no wl_buffer was created and the
++ * X11 window stayed black. Per the linux-dmabuf protocol, INVALID means
++ * "let the compositor infer the layout", so submit it through the dmabuf
++ * path directly instead of rejecting it. */
+ if (xwl_screen->dmabuf &&
+- xwl_glamor_is_modifier_supported(xwl_screen, format, modifier)) {
++ (modifier == DRM_FORMAT_MOD_INVALID ||
++ xwl_glamor_is_modifier_supported(xwl_screen, format, modifier))) {
+ struct zwp_linux_buffer_params_v1 *params;
+
+ params = zwp_linux_dmabuf_v1_create_params(xwl_screen->dmabuf);
+@@ -773,6 +783,15 @@ glamor_pixmap_from_fds(ScreenPtr screen, CARD8 num_fds, const int *fds,
+ strides[0] < width * bpp / 8)
+ goto error;
+
++ /* Some freedreno/kgsl mesa builds (the on-device dev tree) rewrite a
++ * LINEAR modifier (0) to a bogus 1274 (0x4FA) in the loader_dri3
++ * pixmap_from_buffers path. 1274 is not a valid DRM modifier, so the
++ * gbm_bo_import() below rejects it and the X11 GL client gets BadAlloc
++ * (dri3_alloc_render_buffer -> pixmap_from_buffer[s] failed -> segfault).
++ * The buffer is really linear, so map the bogus value back to LINEAR. */
++ if (modifier == 1274ULL)
++ modifier = DRM_FORMAT_MOD_LINEAR;
++
+ if (xwl_gbm->dmabuf_capable && modifier != DRM_FORMAT_MOD_INVALID) {
+ #ifdef GBM_BO_WITH_MODIFIERS
+ struct gbm_import_fd_modifier_data data;
+@@ -1665,27 +1684,37 @@ static Bool
+ xwl_glamor_gbm_init_main_dev(struct xwl_screen *xwl_screen)
+ {
+ struct xwl_gbm_private *xwl_gbm = xwl_gbm_get(xwl_screen);
+- drmDevice *main_dev;
+-
+- while (!xwl_screen->default_feedback.feedback_done) {
+- if (wl_display_dispatch(xwl_screen->display) < 0) {
+- ErrorF("Failed to dispatch Wayland display\n");
+- return FALSE;
++ drmDevice *main_dev = NULL;
++
++ /* linux-dmabuf feedback (and thus a main device) only exists from protocol
++ * version 4. On the kgsl/turnip stack the compositor only speaks v3, so
++ * there is no feedback to wait for - skip the wait and go straight to the
++ * fallback render node below instead of blocking forever on feedback_done. */
++ if (xwl_screen->dmabuf_protocol_version >= 4) {
++ while (!xwl_screen->default_feedback.feedback_done) {
++ if (wl_display_dispatch(xwl_screen->display) < 0) {
++ ErrorF("Failed to dispatch Wayland display\n");
++ return FALSE;
++ }
+ }
++ main_dev = xwl_screen->default_feedback.main_dev;
+ }
+
+- main_dev = xwl_screen->default_feedback.main_dev;
+- if (!main_dev) {
+- ErrorF("No main linux-dmabuf device advertised by compositor\n");
+- return FALSE;
+- }
+-
+- if (!(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
+- ErrorF("Main linux-dmabuf device has no render node\n");
+- return FALSE;
++ /* On the kgsl-backed turnip stack the compositor advertises no usable DRM
++ * render node (the GPU is exposed through kgsl, not a standard DRM node),
++ * so main_dev is NULL or render-node-less. Rather than dereferencing NULL
++ * (-> crash) or bailing out, fall back to a default render node, which the
++ * patched freedreno mesa redirects to /dev/kgsl-3d0 for native GL. */
++ if (!main_dev || !(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
++ const char *fallback = getenv("XWAYLAND_GBM_DEVICE");
++ if (!fallback)
++ fallback = "/dev/dri/renderD128";
++ ErrorF("No usable linux-dmabuf main device, falling back to %s\n",
++ fallback);
++ xwl_gbm->device_name = strdup(fallback);
++ } else {
++ xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ }
+-
+- xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ if (!xwl_gbm->device_name) {
+ return FALSE;
+ }
+diff --git a/hw/xwayland/xwayland-glamor.c b/hw/xwayland/xwayland-glamor.c
+index 88ced5da0..35d1e0391 100644
+--- a/hw/xwayland/xwayland-glamor.c
++++ b/hw/xwayland/xwayland-glamor.c
+@@ -123,6 +123,15 @@ xwl_glamor_has_wl_interfaces(struct xwl_screen *xwl_screen)
+ {
+ if (!xwl_glamor_has_wl_drm(xwl_screen) &&
+ xwl_screen->dmabuf_protocol_version < 4) {
++ /* No wl_drm and no linux-dmabuf feedback (v4). On the kgsl/turnip stack
++ * the compositor exposes neither (the GPU lives behind /dev/kgsl-3d0,
++ * not a DRM render node, so there is no main device to advertise), but
++ * it does speak linux-dmabuf v3. We can still bring glamor up by opening
++ * a fallback render node directly (see xwl_glamor_gbm_init_main_dev) and
++ * submitting buffers over dmabuf v3, so keep glamor available as long as
++ * v3 is present. */
++ if (xwl_screen->dmabuf_protocol_version >= 3)
++ return TRUE;
+ LogMessageVerb(X_INFO, 3, "glamor: 'wl_drm' not supported and linux-dmabuf v4 not supported\n");
+ return FALSE;
+ }
+-- 
+2.47.3
+
diff --git a/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch b/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch
@@ -0,0 +1,142 @@
+From e910fc1dda09b916e190f5f8645abae5b6ebfda3 Mon Sep 17 00:00:00 2001
+From: superturtlee <160681686+superturtlee@users.noreply.github.com>
+Date: Mon, 6 Jul 2026 09:56:24 +0800
+Subject: [PATCH] xwayland: support kgsl dmabuf v3 fallback paths
+
+Allow glamor to initialize with linux-dmabuf v3 when wl_drm and dmabuf
+feedback are unavailable, fall back to a configurable GBM render node, and
+handle implicit or bogus linear modifiers used by kgsl/freedreno stacks.
+
+Based-on-patch: https://github.com/superturtlee/anland/blob/1.11/producers/kde/ubuntu2604/xwayland.patch
+
+Co-authored-by: lfdevs <lfdevs@lfdevs.com>
+---
+ hw/xwayland/xwayland-glamor-gbm.c | 65 ++++++++++++++++++++++---------
+ hw/xwayland/xwayland-glamor.c | 9 +++++
+ 2 files changed, 56 insertions(+), 18 deletions(-)
+
+diff --git a/hw/xwayland/xwayland-glamor-gbm.c b/hw/xwayland/xwayland-glamor-gbm.c
+index 05668b8e9..5ce344b3c 100644
+--- a/hw/xwayland/xwayland-glamor-gbm.c
++++ b/hw/xwayland/xwayland-glamor-gbm.c
+@@ -33,6 +33,7 @@
+ #include <fcntl.h>
+ #include <errno.h>
+ #include <poll.h>
++#include <stdlib.h>
+ #ifdef DRI3
+ #include <sys/eventfd.h>
+ #endif /* DRI3 */
+@@ -590,8 +591,17 @@ xwl_glamor_pixmap_get_wl_buffer(PixmapPtr pixmap)
+ return NULL;
+ }
+
++ /* An implicit-modifier buffer (DRM_FORMAT_MOD_INVALID) is never listed in
++ * the compositor's advertised modifier set, so the regular support check
++ * fails. On the kgsl/turnip stack - where the buffer is allocated on the
++ * display node but composited by turnip - that left both the dmabuf and
++ * the (absent) wl_drm path unusable, so no wl_buffer was created and the
++ * X11 window stayed black. Per the linux-dmabuf protocol, INVALID means
++ * "let the compositor infer the layout", so submit it through the dmabuf
++ * path directly instead of rejecting it. */
+ if (xwl_screen->dmabuf &&
+- xwl_glamor_is_modifier_supported(xwl_screen, format, modifier)) {
++ (modifier == DRM_FORMAT_MOD_INVALID ||
++ xwl_glamor_is_modifier_supported(xwl_screen, format, modifier))) {
+ struct zwp_linux_buffer_params_v1 *params;
+
+ params = zwp_linux_dmabuf_v1_create_params(xwl_screen->dmabuf);
+@@ -773,6 +783,15 @@ glamor_pixmap_from_fds(ScreenPtr screen, CARD8 num_fds, const int *fds,
+ strides[0] < width * bpp / 8)
+ goto error;
+
++ /* Some freedreno/kgsl mesa builds (the on-device dev tree) rewrite a
++ * LINEAR modifier (0) to a bogus 1274 (0x4FA) in the loader_dri3
++ * pixmap_from_buffers path. 1274 is not a valid DRM modifier, so the
++ * gbm_bo_import() below rejects it and the X11 GL client gets BadAlloc
++ * (dri3_alloc_render_buffer -> pixmap_from_buffer[s] failed -> segfault).
++ * The buffer is really linear, so map the bogus value back to LINEAR. */
++ if (modifier == 1274ULL)
++ modifier = DRM_FORMAT_MOD_LINEAR;
++
+ if (xwl_gbm->dmabuf_capable && modifier != DRM_FORMAT_MOD_INVALID) {
+ #ifdef GBM_BO_WITH_MODIFIERS
+ struct gbm_import_fd_modifier_data data;
+@@ -1665,27 +1684,37 @@ static Bool
+ xwl_glamor_gbm_init_main_dev(struct xwl_screen *xwl_screen)
+ {
+ struct xwl_gbm_private *xwl_gbm = xwl_gbm_get(xwl_screen);
+- drmDevice *main_dev;
+-
+- while (!xwl_screen->default_feedback.feedback_done) {
+- if (wl_display_dispatch(xwl_screen->display) < 0) {
+- ErrorF("Failed to dispatch Wayland display\n");
+- return FALSE;
++ drmDevice *main_dev = NULL;
++
++ /* linux-dmabuf feedback (and thus a main device) only exists from protocol
++ * version 4. On the kgsl/turnip stack the compositor only speaks v3, so
++ * there is no feedback to wait for - skip the wait and go straight to the
++ * fallback render node below instead of blocking forever on feedback_done. */
++ if (xwl_screen->dmabuf_protocol_version >= 4) {
++ while (!xwl_screen->default_feedback.feedback_done) {
++ if (wl_display_dispatch(xwl_screen->display) < 0) {
++ ErrorF("Failed to dispatch Wayland display\n");
++ return FALSE;
++ }
+ }
++ main_dev = xwl_screen->default_feedback.main_dev;
+ }
+
+- main_dev = xwl_screen->default_feedback.main_dev;
+- if (!main_dev) {
+- ErrorF("No main linux-dmabuf device advertised by compositor\n");
+- return FALSE;
+- }
+-
+- if (!(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
+- ErrorF("Main linux-dmabuf device has no render node\n");
+- return FALSE;
++ /* On the kgsl-backed turnip stack the compositor advertises no usable DRM
++ * render node (the GPU is exposed through kgsl, not a standard DRM node),
++ * so main_dev is NULL or render-node-less. Rather than dereferencing NULL
++ * (-> crash) or bailing out, fall back to a default render node, which the
++ * patched freedreno mesa redirects to /dev/kgsl-3d0 for native GL. */
++ if (!main_dev || !(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
++ const char *fallback = getenv("XWAYLAND_GBM_DEVICE");
++ if (!fallback)
++ fallback = "/dev/dri/renderD128";
++ ErrorF("No usable linux-dmabuf main device, falling back to %s\n",
++ fallback);
++ xwl_gbm->device_name = strdup(fallback);
++ } else {
++ xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ }
+-
+- xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ if (!xwl_gbm->device_name) {
+ return FALSE;
+ }
+diff --git a/hw/xwayland/xwayland-glamor.c b/hw/xwayland/xwayland-glamor.c
+index 88ced5da0..35d1e0391 100644
+--- a/hw/xwayland/xwayland-glamor.c
++++ b/hw/xwayland/xwayland-glamor.c
+@@ -123,6 +123,15 @@ xwl_glamor_has_wl_interfaces(struct xwl_screen *xwl_screen)
+ {
+ if (!xwl_glamor_has_wl_drm(xwl_screen) &&
+ xwl_screen->dmabuf_protocol_version < 4) {
++ /* No wl_drm and no linux-dmabuf feedback (v4). On the kgsl/turnip stack
++ * the compositor exposes neither (the GPU lives behind /dev/kgsl-3d0,
++ * not a DRM render node, so there is no main device to advertise), but
++ * it does speak linux-dmabuf v3. We can still bring glamor up by opening
++ * a fallback render node directly (see xwl_glamor_gbm_init_main_dev) and
++ * submitting buffers over dmabuf v3, so keep glamor available as long as
++ * v3 is present. */
++ if (xwl_screen->dmabuf_protocol_version >= 3)
++ return TRUE;
+ LogMessageVerb(X_INFO, 3, "glamor: 'wl_drm' not supported and linux-dmabuf v4 not supported\n");
+ return FALSE;
+ }
+-- 
+2.47.3
+
diff --git a/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch b/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch
@@ -0,0 +1,142 @@
+From e910fc1dda09b916e190f5f8645abae5b6ebfda3 Mon Sep 17 00:00:00 2001
+From: superturtlee <160681686+superturtlee@users.noreply.github.com>
+Date: Mon, 6 Jul 2026 09:56:24 +0800
+Subject: [PATCH] xwayland: support kgsl dmabuf v3 fallback paths
+
+Allow glamor to initialize with linux-dmabuf v3 when wl_drm and dmabuf
+feedback are unavailable, fall back to a configurable GBM render node, and
+handle implicit or bogus linear modifiers used by kgsl/freedreno stacks.
+
+Based-on-patch: https://github.com/superturtlee/anland/blob/1.11/producers/kde/ubuntu2604/xwayland.patch
+
+Co-authored-by: lfdevs <lfdevs@lfdevs.com>
+---
+ hw/xwayland/xwayland-glamor-gbm.c | 65 ++++++++++++++++++++++---------
+ hw/xwayland/xwayland-glamor.c | 9 +++++
+ 2 files changed, 56 insertions(+), 18 deletions(-)
+
+diff --git a/hw/xwayland/xwayland-glamor-gbm.c b/hw/xwayland/xwayland-glamor-gbm.c
+index 05668b8e9..5ce344b3c 100644
+--- a/hw/xwayland/xwayland-glamor-gbm.c
++++ b/hw/xwayland/xwayland-glamor-gbm.c
+@@ -33,6 +33,7 @@
+ #include <fcntl.h>
+ #include <errno.h>
+ #include <poll.h>
++#include <stdlib.h>
+ #ifdef DRI3
+ #include <sys/eventfd.h>
+ #endif /* DRI3 */
+@@ -590,8 +591,17 @@ xwl_glamor_pixmap_get_wl_buffer(PixmapPtr pixmap)
+ return NULL;
+ }
+
++ /* An implicit-modifier buffer (DRM_FORMAT_MOD_INVALID) is never listed in
++ * the compositor's advertised modifier set, so the regular support check
++ * fails. On the kgsl/turnip stack - where the buffer is allocated on the
++ * display node but composited by turnip - that left both the dmabuf and
++ * the (absent) wl_drm path unusable, so no wl_buffer was created and the
++ * X11 window stayed black. Per the linux-dmabuf protocol, INVALID means
++ * "let the compositor infer the layout", so submit it through the dmabuf
++ * path directly instead of rejecting it. */
+ if (xwl_screen->dmabuf &&
+- xwl_glamor_is_modifier_supported(xwl_screen, format, modifier)) {
++ (modifier == DRM_FORMAT_MOD_INVALID ||
++ xwl_glamor_is_modifier_supported(xwl_screen, format, modifier))) {
+ struct zwp_linux_buffer_params_v1 *params;
+
+ params = zwp_linux_dmabuf_v1_create_params(xwl_screen->dmabuf);
+@@ -773,6 +783,15 @@ glamor_pixmap_from_fds(ScreenPtr screen, CARD8 num_fds, const int *fds,
+ strides[0] < width * bpp / 8)
+ goto error;
+
++ /* Some freedreno/kgsl mesa builds (the on-device dev tree) rewrite a
++ * LINEAR modifier (0) to a bogus 1274 (0x4FA) in the loader_dri3
++ * pixmap_from_buffers path. 1274 is not a valid DRM modifier, so the
++ * gbm_bo_import() below rejects it and the X11 GL client gets BadAlloc
++ * (dri3_alloc_render_buffer -> pixmap_from_buffer[s] failed -> segfault).
++ * The buffer is really linear, so map the bogus value back to LINEAR. */
++ if (modifier == 1274ULL)
++ modifier = DRM_FORMAT_MOD_LINEAR;
++
+ if (xwl_gbm->dmabuf_capable && modifier != DRM_FORMAT_MOD_INVALID) {
+ #ifdef GBM_BO_WITH_MODIFIERS
+ struct gbm_import_fd_modifier_data data;
+@@ -1665,27 +1684,37 @@ static Bool
+ xwl_glamor_gbm_init_main_dev(struct xwl_screen *xwl_screen)
+ {
+ struct xwl_gbm_private *xwl_gbm = xwl_gbm_get(xwl_screen);
+- drmDevice *main_dev;
+-
+- while (!xwl_screen->default_feedback.feedback_done) {
+- if (wl_display_dispatch(xwl_screen->display) < 0) {
+- ErrorF("Failed to dispatch Wayland display\n");
+- return FALSE;
++ drmDevice *main_dev = NULL;
++
++ /* linux-dmabuf feedback (and thus a main device) only exists from protocol
++ * version 4. On the kgsl/turnip stack the compositor only speaks v3, so
++ * there is no feedback to wait for - skip the wait and go straight to the
++ * fallback render node below instead of blocking forever on feedback_done. */
++ if (xwl_screen->dmabuf_protocol_version >= 4) {
++ while (!xwl_screen->default_feedback.feedback_done) {
++ if (wl_display_dispatch(xwl_screen->display) < 0) {
++ ErrorF("Failed to dispatch Wayland display\n");
++ return FALSE;
++ }
+ }
++ main_dev = xwl_screen->default_feedback.main_dev;
+ }
+
+- main_dev = xwl_screen->default_feedback.main_dev;
+- if (!main_dev) {
+- ErrorF("No main linux-dmabuf device advertised by compositor\n");
+- return FALSE;
+- }
+-
+- if (!(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
+- ErrorF("Main linux-dmabuf device has no render node\n");
+- return FALSE;
++ /* On the kgsl-backed turnip stack the compositor advertises no usable DRM
++ * render node (the GPU is exposed through kgsl, not a standard DRM node),
++ * so main_dev is NULL or render-node-less. Rather than dereferencing NULL
++ * (-> crash) or bailing out, fall back to a default render node, which the
++ * patched freedreno mesa redirects to /dev/kgsl-3d0 for native GL. */
++ if (!main_dev || !(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
++ const char *fallback = getenv("XWAYLAND_GBM_DEVICE");
++ if (!fallback)
++ fallback = "/dev/dri/renderD128";
++ ErrorF("No usable linux-dmabuf main device, falling back to %s\n",
++ fallback);
++ xwl_gbm->device_name = strdup(fallback);
++ } else {
++ xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ }
+-
+- xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ if (!xwl_gbm->device_name) {
+ return FALSE;
+ }
+diff --git a/hw/xwayland/xwayland-glamor.c b/hw/xwayland/xwayland-glamor.c
+index 88ced5da0..35d1e0391 100644
+--- a/hw/xwayland/xwayland-glamor.c
++++ b/hw/xwayland/xwayland-glamor.c
+@@ -123,6 +123,15 @@ xwl_glamor_has_wl_interfaces(struct xwl_screen *xwl_screen)
+ {
+ if (!xwl_glamor_has_wl_drm(xwl_screen) &&
+ xwl_screen->dmabuf_protocol_version < 4) {
++ /* No wl_drm and no linux-dmabuf feedback (v4). On the kgsl/turnip stack
++ * the compositor exposes neither (the GPU lives behind /dev/kgsl-3d0,
++ * not a DRM render node, so there is no main device to advertise), but
++ * it does speak linux-dmabuf v3. We can still bring glamor up by opening
++ * a fallback render node directly (see xwl_glamor_gbm_init_main_dev) and
++ * submitting buffers over dmabuf v3, so keep glamor available as long as
++ * v3 is present. */
++ if (xwl_screen->dmabuf_protocol_version >= 3)
++ return TRUE;
+ LogMessageVerb(X_INFO, 3, "glamor: 'wl_drm' not supported and linux-dmabuf v4 not supported\n");
+ return FALSE;
+ }
+-- 
+2.47.3
+
diff --git a/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch b/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch
@@ -0,0 +1,142 @@
+From e910fc1dda09b916e190f5f8645abae5b6ebfda3 Mon Sep 17 00:00:00 2001
+From: superturtlee <160681686+superturtlee@users.noreply.github.com>
+Date: Mon, 6 Jul 2026 09:56:24 +0800
+Subject: [PATCH] xwayland: support kgsl dmabuf v3 fallback paths
+
+Allow glamor to initialize with linux-dmabuf v3 when wl_drm and dmabuf
+feedback are unavailable, fall back to a configurable GBM render node, and
+handle implicit or bogus linear modifiers used by kgsl/freedreno stacks.
+
+Based-on-patch: https://github.com/superturtlee/anland/blob/1.11/producers/kde/ubuntu2604/xwayland.patch
+
+Co-authored-by: lfdevs <lfdevs@lfdevs.com>
+---
+ hw/xwayland/xwayland-glamor-gbm.c | 65 ++++++++++++++++++++++---------
+ hw/xwayland/xwayland-glamor.c | 9 +++++
+ 2 files changed, 56 insertions(+), 18 deletions(-)
+
+diff --git a/hw/xwayland/xwayland-glamor-gbm.c b/hw/xwayland/xwayland-glamor-gbm.c
+index 05668b8e9..5ce344b3c 100644
+--- a/hw/xwayland/xwayland-glamor-gbm.c
++++ b/hw/xwayland/xwayland-glamor-gbm.c
+@@ -33,6 +33,7 @@
+ #include <fcntl.h>
+ #include <errno.h>
+ #include <poll.h>
++#include <stdlib.h>
+ #ifdef DRI3
+ #include <sys/eventfd.h>
+ #endif /* DRI3 */
+@@ -590,8 +591,17 @@ xwl_glamor_pixmap_get_wl_buffer(PixmapPtr pixmap)
+ return NULL;
+ }
+
++ /* An implicit-modifier buffer (DRM_FORMAT_MOD_INVALID) is never listed in
++ * the compositor's advertised modifier set, so the regular support check
++ * fails. On the kgsl/turnip stack - where the buffer is allocated on the
++ * display node but composited by turnip - that left both the dmabuf and
++ * the (absent) wl_drm path unusable, so no wl_buffer was created and the
++ * X11 window stayed black. Per the linux-dmabuf protocol, INVALID means
++ * "let the compositor infer the layout", so submit it through the dmabuf
++ * path directly instead of rejecting it. */
+ if (xwl_screen->dmabuf &&
+- xwl_glamor_is_modifier_supported(xwl_screen, format, modifier)) {
++ (modifier == DRM_FORMAT_MOD_INVALID ||
++ xwl_glamor_is_modifier_supported(xwl_screen, format, modifier))) {
+ struct zwp_linux_buffer_params_v1 *params;
+
+ params = zwp_linux_dmabuf_v1_create_params(xwl_screen->dmabuf);
+@@ -773,6 +783,15 @@ glamor_pixmap_from_fds(ScreenPtr screen, CARD8 num_fds, const int *fds,
+ strides[0] < width * bpp / 8)
+ goto error;
+
++ /* Some freedreno/kgsl mesa builds (the on-device dev tree) rewrite a
++ * LINEAR modifier (0) to a bogus 1274 (0x4FA) in the loader_dri3
++ * pixmap_from_buffers path. 1274 is not a valid DRM modifier, so the
++ * gbm_bo_import() below rejects it and the X11 GL client gets BadAlloc
++ * (dri3_alloc_render_buffer -> pixmap_from_buffer[s] failed -> segfault).
++ * The buffer is really linear, so map the bogus value back to LINEAR. */
++ if (modifier == 1274ULL)
++ modifier = DRM_FORMAT_MOD_LINEAR;
++
+ if (xwl_gbm->dmabuf_capable && modifier != DRM_FORMAT_MOD_INVALID) {
+ #ifdef GBM_BO_WITH_MODIFIERS
+ struct gbm_import_fd_modifier_data data;
+@@ -1665,27 +1684,37 @@ static Bool
+ xwl_glamor_gbm_init_main_dev(struct xwl_screen *xwl_screen)
+ {
+ struct xwl_gbm_private *xwl_gbm = xwl_gbm_get(xwl_screen);
+- drmDevice *main_dev;
+-
+- while (!xwl_screen->default_feedback.feedback_done) {
+- if (wl_display_dispatch(xwl_screen->display) < 0) {
+- ErrorF("Failed to dispatch Wayland display\n");
+- return FALSE;
++ drmDevice *main_dev = NULL;
++
++ /* linux-dmabuf feedback (and thus a main device) only exists from protocol
++ * version 4. On the kgsl/turnip stack the compositor only speaks v3, so
++ * there is no feedback to wait for - skip the wait and go straight to the
++ * fallback render node below instead of blocking forever on feedback_done. */
++ if (xwl_screen->dmabuf_protocol_version >= 4) {
++ while (!xwl_screen->default_feedback.feedback_done) {
++ if (wl_display_dispatch(xwl_screen->display) < 0) {
++ ErrorF("Failed to dispatch Wayland display\n");
++ return FALSE;
++ }
+ }
++ main_dev = xwl_screen->default_feedback.main_dev;
+ }
+
+- main_dev = xwl_screen->default_feedback.main_dev;
+- if (!main_dev) {
+- ErrorF("No main linux-dmabuf device advertised by compositor\n");
+- return FALSE;
+- }
+-
+- if (!(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
+- ErrorF("Main linux-dmabuf device has no render node\n");
+- return FALSE;
++ /* On the kgsl-backed turnip stack the compositor advertises no usable DRM
++ * render node (the GPU is exposed through kgsl, not a standard DRM node),
++ * so main_dev is NULL or render-node-less. Rather than dereferencing NULL
++ * (-> crash) or bailing out, fall back to a default render node, which the
++ * patched freedreno mesa redirects to /dev/kgsl-3d0 for native GL. */
++ if (!main_dev || !(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
++ const char *fallback = getenv("XWAYLAND_GBM_DEVICE");
++ if (!fallback)
++ fallback = "/dev/dri/renderD128";
++ ErrorF("No usable linux-dmabuf main device, falling back to %s\n",
++ fallback);
++ xwl_gbm->device_name = strdup(fallback);
++ } else {
++ xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ }
+-
+- xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ if (!xwl_gbm->device_name) {
+ return FALSE;
+ }
+diff --git a/hw/xwayland/xwayland-glamor.c b/hw/xwayland/xwayland-glamor.c
+index 88ced5da0..35d1e0391 100644
+--- a/hw/xwayland/xwayland-glamor.c
++++ b/hw/xwayland/xwayland-glamor.c
+@@ -123,6 +123,15 @@ xwl_glamor_has_wl_interfaces(struct xwl_screen *xwl_screen)
+ {
+ if (!xwl_glamor_has_wl_drm(xwl_screen) &&
+ xwl_screen->dmabuf_protocol_version < 4) {
++ /* No wl_drm and no linux-dmabuf feedback (v4). On the kgsl/turnip stack
++ * the compositor exposes neither (the GPU lives behind /dev/kgsl-3d0,
++ * not a DRM render node, so there is no main device to advertise), but
++ * it does speak linux-dmabuf v3. We can still bring glamor up by opening
++ * a fallback render node directly (see xwl_glamor_gbm_init_main_dev) and
++ * submitting buffers over dmabuf v3, so keep glamor available as long as
++ * v3 is present. */
++ if (xwl_screen->dmabuf_protocol_version >= 3)
++ return TRUE;
+ LogMessageVerb(X_INFO, 3, "glamor: 'wl_drm' not supported and linux-dmabuf v4 not supported\n");
+ return FALSE;
+ }
+-- 
+2.47.3
+
diff --git a/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch b/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch
@@ -0,0 +1,142 @@
+From e910fc1dda09b916e190f5f8645abae5b6ebfda3 Mon Sep 17 00:00:00 2001
+From: superturtlee <160681686+superturtlee@users.noreply.github.com>
+Date: Mon, 6 Jul 2026 09:56:24 +0800
+Subject: [PATCH] xwayland: support kgsl dmabuf v3 fallback paths
+
+Allow glamor to initialize with linux-dmabuf v3 when wl_drm and dmabuf
+feedback are unavailable, fall back to a configurable GBM render node, and
+handle implicit or bogus linear modifiers used by kgsl/freedreno stacks.
+
+Based-on-patch: https://github.com/superturtlee/anland/blob/1.11/producers/kde/ubuntu2604/xwayland.patch
+
+Co-authored-by: lfdevs <lfdevs@lfdevs.com>
+---
+ hw/xwayland/xwayland-glamor-gbm.c | 65 ++++++++++++++++++++++---------
+ hw/xwayland/xwayland-glamor.c | 9 +++++
+ 2 files changed, 56 insertions(+), 18 deletions(-)
+
+diff --git a/hw/xwayland/xwayland-glamor-gbm.c b/hw/xwayland/xwayland-glamor-gbm.c
+index 05668b8e9..5ce344b3c 100644
+--- a/hw/xwayland/xwayland-glamor-gbm.c
++++ b/hw/xwayland/xwayland-glamor-gbm.c
+@@ -33,6 +33,7 @@
+ #include <fcntl.h>
+ #include <errno.h>
+ #include <poll.h>
++#include <stdlib.h>
+ #ifdef DRI3
+ #include <sys/eventfd.h>
+ #endif /* DRI3 */
+@@ -590,8 +591,17 @@ xwl_glamor_pixmap_get_wl_buffer(PixmapPtr pixmap)
+ return NULL;
+ }
+
++ /* An implicit-modifier buffer (DRM_FORMAT_MOD_INVALID) is never listed in
++ * the compositor's advertised modifier set, so the regular support check
++ * fails. On the kgsl/turnip stack - where the buffer is allocated on the
++ * display node but composited by turnip - that left both the dmabuf and
++ * the (absent) wl_drm path unusable, so no wl_buffer was created and the
++ * X11 window stayed black. Per the linux-dmabuf protocol, INVALID means
++ * "let the compositor infer the layout", so submit it through the dmabuf
++ * path directly instead of rejecting it. */
+ if (xwl_screen->dmabuf &&
+- xwl_glamor_is_modifier_supported(xwl_screen, format, modifier)) {
++ (modifier == DRM_FORMAT_MOD_INVALID ||
++ xwl_glamor_is_modifier_supported(xwl_screen, format, modifier))) {
+ struct zwp_linux_buffer_params_v1 *params;
+
+ params = zwp_linux_dmabuf_v1_create_params(xwl_screen->dmabuf);
+@@ -773,6 +783,15 @@ glamor_pixmap_from_fds(ScreenPtr screen, CARD8 num_fds, const int *fds,
+ strides[0] < width * bpp / 8)
+ goto error;
+
++ /* Some freedreno/kgsl mesa builds (the on-device dev tree) rewrite a
++ * LINEAR modifier (0) to a bogus 1274 (0x4FA) in the loader_dri3
++ * pixmap_from_buffers path. 1274 is not a valid DRM modifier, so the
++ * gbm_bo_import() below rejects it and the X11 GL client gets BadAlloc
++ * (dri3_alloc_render_buffer -> pixmap_from_buffer[s] failed -> segfault).
++ * The buffer is really linear, so map the bogus value back to LINEAR. */
++ if (modifier == 1274ULL)
++ modifier = DRM_FORMAT_MOD_LINEAR;
++
+ if (xwl_gbm->dmabuf_capable && modifier != DRM_FORMAT_MOD_INVALID) {
+ #ifdef GBM_BO_WITH_MODIFIERS
+ struct gbm_import_fd_modifier_data data;
+@@ -1665,27 +1684,37 @@ static Bool
+ xwl_glamor_gbm_init_main_dev(struct xwl_screen *xwl_screen)
+ {
+ struct xwl_gbm_private *xwl_gbm = xwl_gbm_get(xwl_screen);
+- drmDevice *main_dev;
+-
+- while (!xwl_screen->default_feedback.feedback_done) {
+- if (wl_display_dispatch(xwl_screen->display) < 0) {
+- ErrorF("Failed to dispatch Wayland display\n");
+- return FALSE;
++ drmDevice *main_dev = NULL;
++
++ /* linux-dmabuf feedback (and thus a main device) only exists from protocol
++ * version 4. On the kgsl/turnip stack the compositor only speaks v3, so
++ * there is no feedback to wait for - skip the wait and go straight to the
++ * fallback render node below instead of blocking forever on feedback_done. */
++ if (xwl_screen->dmabuf_protocol_version >= 4) {
++ while (!xwl_screen->default_feedback.feedback_done) {
++ if (wl_display_dispatch(xwl_screen->display) < 0) {
++ ErrorF("Failed to dispatch Wayland display\n");
++ return FALSE;
++ }
+ }
++ main_dev = xwl_screen->default_feedback.main_dev;
+ }
+
+- main_dev = xwl_screen->default_feedback.main_dev;
+- if (!main_dev) {
+- ErrorF("No main linux-dmabuf device advertised by compositor\n");
+- return FALSE;
+- }
+-
+- if (!(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
+- ErrorF("Main linux-dmabuf device has no render node\n");
+- return FALSE;
++ /* On the kgsl-backed turnip stack the compositor advertises no usable DRM
++ * render node (the GPU is exposed through kgsl, not a standard DRM node),
++ * so main_dev is NULL or render-node-less. Rather than dereferencing NULL
++ * (-> crash) or bailing out, fall back to a default render node, which the
++ * patched freedreno mesa redirects to /dev/kgsl-3d0 for native GL. */
++ if (!main_dev || !(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
++ const char *fallback = getenv("XWAYLAND_GBM_DEVICE");
++ if (!fallback)
++ fallback = "/dev/dri/renderD128";
++ ErrorF("No usable linux-dmabuf main device, falling back to %s\n",
++ fallback);
++ xwl_gbm->device_name = strdup(fallback);
++ } else {
++ xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ }
+-
+- xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ if (!xwl_gbm->device_name) {
+ return FALSE;
+ }
+diff --git a/hw/xwayland/xwayland-glamor.c b/hw/xwayland/xwayland-glamor.c
+index 88ced5da0..35d1e0391 100644
+--- a/hw/xwayland/xwayland-glamor.c
++++ b/hw/xwayland/xwayland-glamor.c
+@@ -123,6 +123,15 @@ xwl_glamor_has_wl_interfaces(struct xwl_screen *xwl_screen)
+ {
+ if (!xwl_glamor_has_wl_drm(xwl_screen) &&
+ xwl_screen->dmabuf_protocol_version < 4) {
++ /* No wl_drm and no linux-dmabuf feedback (v4). On the kgsl/turnip stack
++ * the compositor exposes neither (the GPU lives behind /dev/kgsl-3d0,
++ * not a DRM render node, so there is no main device to advertise), but
++ * it does speak linux-dmabuf v3. We can still bring glamor up by opening
++ * a fallback render node directly (see xwl_glamor_gbm_init_main_dev) and
++ * submitting buffers over dmabuf v3, so keep glamor available as long as
++ * v3 is present. */
++ if (xwl_screen->dmabuf_protocol_version >= 3)
++ return TRUE;
+ LogMessageVerb(X_INFO, 3, "glamor: 'wl_drm' not supported and linux-dmabuf v4 not supported\n");
+ return FALSE;
+ }
+-- 
+2.47.3
+
diff --git a/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch b/x11-packages/xwayland/0001-xwayland-support-kgsl-dmabuf-v3-fallback-paths.patch
@@ -0,0 +1,142 @@
+From e910fc1dda09b916e190f5f8645abae5b6ebfda3 Mon Sep 17 00:00:00 2001
+From: superturtlee <160681686+superturtlee@users.noreply.github.com>
+Date: Mon, 6 Jul 2026 09:56:24 +0800
+Subject: [PATCH] xwayland: support kgsl dmabuf v3 fallback paths
+
+Allow glamor to initialize with linux-dmabuf v3 when wl_drm and dmabuf
+feedback are unavailable, fall back to a configurable GBM render node, and
+handle implicit or bogus linear modifiers used by kgsl/freedreno stacks.
+
+Based-on-patch: https://github.com/superturtlee/anland/blob/1.11/producers/kde/ubuntu2604/xwayland.patch
+
+Co-authored-by: lfdevs <lfdevs@lfdevs.com>
+---
+ hw/xwayland/xwayland-glamor-gbm.c | 65 ++++++++++++++++++++++---------
+ hw/xwayland/xwayland-glamor.c | 9 +++++
+ 2 files changed, 56 insertions(+), 18 deletions(-)
+
+diff --git a/hw/xwayland/xwayland-glamor-gbm.c b/hw/xwayland/xwayland-glamor-gbm.c
+index 05668b8e9..5ce344b3c 100644
+--- a/hw/xwayland/xwayland-glamor-gbm.c
++++ b/hw/xwayland/xwayland-glamor-gbm.c
+@@ -33,6 +33,7 @@
+ #include <fcntl.h>
+ #include <errno.h>
+ #include <poll.h>
++#include <stdlib.h>
+ #ifdef DRI3
+ #include <sys/eventfd.h>
+ #endif /* DRI3 */
+@@ -590,8 +591,17 @@ xwl_glamor_pixmap_get_wl_buffer(PixmapPtr pixmap)
+ return NULL;
+ }
+
++ /* An implicit-modifier buffer (DRM_FORMAT_MOD_INVALID) is never listed in
++ * the compositor's advertised modifier set, so the regular support check
++ * fails. On the kgsl/turnip stack - where the buffer is allocated on the
++ * display node but composited by turnip - that left both the dmabuf and
++ * the (absent) wl_drm path unusable, so no wl_buffer was created and the
++ * X11 window stayed black. Per the linux-dmabuf protocol, INVALID means
++ * "let the compositor infer the layout", so submit it through the dmabuf
++ * path directly instead of rejecting it. */
+ if (xwl_screen->dmabuf &&
+- xwl_glamor_is_modifier_supported(xwl_screen, format, modifier)) {
++ (modifier == DRM_FORMAT_MOD_INVALID ||
++ xwl_glamor_is_modifier_supported(xwl_screen, format, modifier))) {
+ struct zwp_linux_buffer_params_v1 *params;
+
+ params = zwp_linux_dmabuf_v1_create_params(xwl_screen->dmabuf);
+@@ -773,6 +783,15 @@ glamor_pixmap_from_fds(ScreenPtr screen, CARD8 num_fds, const int *fds,
+ strides[0] < width * bpp / 8)
+ goto error;
+
++ /* Some freedreno/kgsl mesa builds (the on-device dev tree) rewrite a
++ * LINEAR modifier (0) to a bogus 1274 (0x4FA) in the loader_dri3
++ * pixmap_from_buffers path. 1274 is not a valid DRM modifier, so the
++ * gbm_bo_import() below rejects it and the X11 GL client gets BadAlloc
++ * (dri3_alloc_render_buffer -> pixmap_from_buffer[s] failed -> segfault).
++ * The buffer is really linear, so map the bogus value back to LINEAR. */
++ if (modifier == 1274ULL)
++ modifier = DRM_FORMAT_MOD_LINEAR;
++
+ if (xwl_gbm->dmabuf_capable && modifier != DRM_FORMAT_MOD_INVALID) {
+ #ifdef GBM_BO_WITH_MODIFIERS
+ struct gbm_import_fd_modifier_data data;
+@@ -1665,27 +1684,37 @@ static Bool
+ xwl_glamor_gbm_init_main_dev(struct xwl_screen *xwl_screen)
+ {
+ struct xwl_gbm_private *xwl_gbm = xwl_gbm_get(xwl_screen);
+- drmDevice *main_dev;
+-
+- while (!xwl_screen->default_feedback.feedback_done) {
+- if (wl_display_dispatch(xwl_screen->display) < 0) {
+- ErrorF("Failed to dispatch Wayland display\n");
+- return FALSE;
++ drmDevice *main_dev = NULL;
++
++ /* linux-dmabuf feedback (and thus a main device) only exists from protocol
++ * version 4. On the kgsl/turnip stack the compositor only speaks v3, so
++ * there is no feedback to wait for - skip the wait and go straight to the
++ * fallback render node below instead of blocking forever on feedback_done. */
++ if (xwl_screen->dmabuf_protocol_version >= 4) {
++ while (!xwl_screen->default_feedback.feedback_done) {
++ if (wl_display_dispatch(xwl_screen->display) < 0) {
++ ErrorF("Failed to dispatch Wayland display\n");
++ return FALSE;
++ }
+ }
++ main_dev = xwl_screen->default_feedback.main_dev;
+ }
+
+- main_dev = xwl_screen->default_feedback.main_dev;
+- if (!main_dev) {
+- ErrorF("No main linux-dmabuf device advertised by compositor\n");
+- return FALSE;
+- }
+-
+- if (!(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
+- ErrorF("Main linux-dmabuf device has no render node\n");
+- return FALSE;
++ /* On the kgsl-backed turnip stack the compositor advertises no usable DRM
++ * render node (the GPU is exposed through kgsl, not a standard DRM node),
++ * so main_dev is NULL or render-node-less. Rather than dereferencing NULL
++ * (-> crash) or bailing out, fall back to a default render node, which the
++ * patched freedreno mesa redirects to /dev/kgsl-3d0 for native GL. */
++ if (!main_dev || !(main_dev->available_nodes & (1 << DRM_NODE_RENDER))) {
++ const char *fallback = getenv("XWAYLAND_GBM_DEVICE");
++ if (!fallback)
++ fallback = "/dev/dri/renderD128";
++ ErrorF("No usable linux-dmabuf main device, falling back to %s\n",
++ fallback);
++ xwl_gbm->device_name = strdup(fallback);
++ } else {
++ xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ }
+-
+- xwl_gbm->device_name = strdup(main_dev->nodes[DRM_NODE_RENDER]);
+ if (!xwl_gbm->device_name) {
+ return FALSE;
+ }
+diff --git a/hw/xwayland/xwayland-glamor.c b/hw/xwayland/xwayland-glamor.c
+index 88ced5da0..35d1e0391 100644
+--- a/hw/xwayland/xwayland-glamor.c
++++ b/hw/xwayland/xwayland-glamor.c
+@@ -123,6 +123,15 @@ xwl_glamor_has_wl_interfaces(struct xwl_screen *xwl_screen)
+ {
+ if (!xwl_glamor_has_wl_drm(xwl_screen) &&
+ xwl_screen->dmabuf_protocol_version < 4) {
++ /* No wl_drm and no linux-dmabuf feedback (v4). On the kgsl/turnip stack
++ * the compositor exposes neither (the GPU lives behind /dev/kgsl-3d0,
++ * not a DRM render node, so there is no main device to advertise), but
++ * it does speak linux-dmabuf v3. We can still bring glamor up by opening
++ * a fallback render node directly (see xwl_glamor_gbm_init_main_dev) and
++ * submitting buffers over dmabuf v3, so keep glamor available as long as
++ * v3 is present. */
++ if (xwl_screen->dmabuf_protocol_version >= 3)
++ return TRUE;
+ LogMessageVerb(X_INFO, 3, "glamor: 'wl_drm' not supported and linux-dmabuf v4 not supported\n");
+ return FALSE;
+ }
+-- 
+2.47.3
+