This is a note to let you know that I've just added the patch titled drm/simpledrm: Fix return type of simpledrm_simple_display_pipe_mode_valid() to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-simpledrm-fix-return-type-of-simpledrm_simple_display_pipe_mode_valid.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 0c09bc33aa8e9dc867300acaadc318c2f0d85a1e Mon Sep 17 00:00:00 2001 From: Nathan Chancellor <nathan@xxxxxxxxxx> Date: Mon, 25 Jul 2022 16:36:29 -0700 Subject: drm/simpledrm: Fix return type of simpledrm_simple_display_pipe_mode_valid() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Nathan Chancellor <nathan@xxxxxxxxxx> commit 0c09bc33aa8e9dc867300acaadc318c2f0d85a1e upstream. When booting a kernel compiled with clang's CFI protection (CONFIG_CFI_CLANG), there is a CFI failure in drm_simple_kms_crtc_mode_valid() when trying to call simpledrm_simple_display_pipe_mode_valid() through ->mode_valid(): [ 0.322802] CFI failure (target: simpledrm_simple_display_pipe_mode_valid+0x0/0x8): ... [ 0.324928] Call trace: [ 0.324969] __ubsan_handle_cfi_check_fail+0x58/0x60 [ 0.325053] __cfi_check_fail+0x3c/0x44 [ 0.325120] __cfi_slowpath_diag+0x178/0x200 [ 0.325192] drm_simple_kms_crtc_mode_valid+0x58/0x80 [ 0.325279] __drm_helper_update_and_validate+0x31c/0x464 ... The ->mode_valid() member in 'struct drm_simple_display_pipe_funcs' expects a return type of 'enum drm_mode_status', not 'int'. Correct it to fix the CFI failure. Cc: stable@xxxxxxxxxxxxxxx Fixes: 11e8f5fd223b ("drm: Add simpledrm driver") Link: https://github.com/ClangBuiltLinux/linux/issues/1647 Reported-by: Tomasz Paweł Gajc <tpgxyz@xxxxxxxxx> Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx> Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx> Reviewed-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20220725233629.223223-1-nathan@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/tiny/simpledrm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/gpu/drm/tiny/simpledrm.c +++ b/drivers/gpu/drm/tiny/simpledrm.c @@ -614,7 +614,7 @@ static const struct drm_connector_funcs .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, }; -static int +static enum drm_mode_status simpledrm_simple_display_pipe_mode_valid(struct drm_simple_display_pipe *pipe, const struct drm_display_mode *mode) { Patches currently in stable-queue which might be from nathan@xxxxxxxxxx are queue-5.15/drm-simpledrm-fix-return-type-of-simpledrm_simple_display_pipe_mode_valid.patch