The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 951df98024f7272f85df5044eca7374f5b5b24ef # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '167820549723129@kroah.com' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
951df98024f7 ("drm/gud: Fix UBSAN warning") edbe262acf92 ("drm/format-helper: Merge drm_fb_memcpy() and drm_fb_memcpy_toio()") 71bf55872cbe ("drm/format-helper: Provide drm_fb_blit()") de40c281fe0b ("drm/simpledrm: Convert to atomic helpers") c25b69604fc4 ("drm/simpledrm: Inline device-init helpers") 03d38605cee7 ("drm/simpledrm: Remove mem field from device structure") f9929f69de94 ("drm/simpledrm: Fix return type of simpledrm_simple_display_pipe_mode_valid()") 4f4dc37e374c ("drm/mgag200: Reorganize before dropping simple-KMS helpers") 475e2b970cc3 ("drm/mgag200: Split up connector's mode_valid helper") 69340e529a06 ("drm/mgag200: Test memory requirements in drm_mode_config_funcs.mode_valid") 8219f11fdaf5 ("drm/mgag200: Remove struct mga_connector") b279df242972 ("drm/mgag200: Switch I2C code to managed cleanup") 16f1456466c2 ("drm/mgag200: Implement connector's get_modes with helper") d50f74790bbb ("drm/mgag200: Fail on I2C initialization errors") 5913ab941d6e ("drm/mgag200: Acquire I/O lock while reading EDID") c48a36301634 ("drm/mgag200: Optimize damage clips") 931e3f3a0e99 ("drm/mgag200: Protect concurrent access to I/O registers with lock") 41fd6f0a6dd6 ("drm/format-helper: Implement drm_fb_swab() with per-line helpers") d7442505de92 ("drm/simpledrm: Use fbdev defaults for shadow buffering") e08a99d00558 ("drm/format-helper: Add RGB565-to-XRGB8888 conversion")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 951df98024f7272f85df5044eca7374f5b5b24ef Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= noralf@tronnes.org Date: Wed, 30 Nov 2022 20:26:49 +0100 Subject: [PATCH] drm/gud: Fix UBSAN warning MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit
UBSAN complains about invalid value for bool:
[ 101.165172] [drm] Initialized gud 1.0.0 20200422 for 2-3.2:1.0 on minor 1 [ 101.213360] gud 2-3.2:1.0: [drm] fb1: guddrmfb frame buffer device [ 101.213426] usbcore: registered new interface driver gud [ 101.989431] ================================================================================ [ 101.989441] UBSAN: invalid-load in linux/include/linux/iosys-map.h:253:9 [ 101.989447] load of value 121 is not a valid value for type '_Bool' [ 101.989451] CPU: 1 PID: 455 Comm: kworker/1:6 Not tainted 5.18.0-rc5-gud-5.18-rc5 #3 [ 101.989456] Hardware name: Hewlett-Packard HP EliteBook 820 G1/1991, BIOS L71 Ver. 01.44 04/12/2018 [ 101.989459] Workqueue: events_long gud_flush_work [gud] [ 101.989471] Call Trace: [ 101.989474] <TASK> [ 101.989479] dump_stack_lvl+0x49/0x5f [ 101.989488] dump_stack+0x10/0x12 [ 101.989493] ubsan_epilogue+0x9/0x3b [ 101.989498] __ubsan_handle_load_invalid_value.cold+0x44/0x49 [ 101.989504] dma_buf_vmap.cold+0x38/0x3d [ 101.989511] ? find_busiest_group+0x48/0x300 [ 101.989520] drm_gem_shmem_vmap+0x76/0x1b0 [drm_shmem_helper] [ 101.989528] drm_gem_shmem_object_vmap+0x9/0xb [drm_shmem_helper] [ 101.989535] drm_gem_vmap+0x26/0x60 [drm] [ 101.989594] drm_gem_fb_vmap+0x47/0x150 [drm_kms_helper] [ 101.989630] gud_prep_flush+0xc1/0x710 [gud] [ 101.989639] ? _raw_spin_lock+0x17/0x40 [ 101.989648] gud_flush_work+0x1e0/0x430 [gud] [ 101.989653] ? __switch_to+0x11d/0x470 [ 101.989664] process_one_work+0x21f/0x3f0 [ 101.989673] worker_thread+0x200/0x3e0 [ 101.989679] ? rescuer_thread+0x390/0x390 [ 101.989684] kthread+0xfd/0x130 [ 101.989690] ? kthread_complete_and_exit+0x20/0x20 [ 101.989696] ret_from_fork+0x22/0x30 [ 101.989706] </TASK> [ 101.989708] ================================================================================
The source of this warning is in iosys_map_clear() called from dma_buf_vmap(). It conditionally sets values based on map->is_iomem. The iosys_map variables are allocated uninitialized on the stack leading to ->is_iomem having all kinds of values and not only 0/1.
Fix this by zeroing the iosys_map variables.
Fixes: 40e1a70b4aed ("drm: Add GUD USB Display driver") Cc: stable@vger.kernel.org # v5.18+ Reviewed-by: Javier Martinez Canillas javierm@redhat.com Reviewed-by: Thomas Zimmermann tzimmermann@suse.de Signed-off-by: Noralf Trønnes noralf@tronnes.org Link: https://patchwork.freedesktop.org/patch/msgid/20221122-gud-shadow-plane-v2-1...
diff --git a/drivers/gpu/drm/gud/gud_pipe.c b/drivers/gpu/drm/gud/gud_pipe.c index 7c6dc2bcd14a..61f4abaf1811 100644 --- a/drivers/gpu/drm/gud/gud_pipe.c +++ b/drivers/gpu/drm/gud/gud_pipe.c @@ -157,8 +157,8 @@ static int gud_prep_flush(struct gud_device *gdrm, struct drm_framebuffer *fb, { struct dma_buf_attachment *import_attach = fb->obj[0]->import_attach; u8 compression = gdrm->compression; - struct iosys_map map[DRM_FORMAT_MAX_PLANES]; - struct iosys_map map_data[DRM_FORMAT_MAX_PLANES]; + struct iosys_map map[DRM_FORMAT_MAX_PLANES] = { }; + struct iosys_map map_data[DRM_FORMAT_MAX_PLANES] = { }; struct iosys_map dst; void *vaddr, *buf; size_t pitch, len;