Stephen Boyd a74f0f0a62 drm/msm: Avoid div-by-zero in dpu_crtc_atomic_check() ... [ Upstream commit 22f7609418 ] The cstate->num_mixers member is only set to a non-zero value once dpu_encoder_virt_mode_set() is called, but the atomic check function can be called by userspace before that. Let's avoid the div-by-zero here and inside _dpu_crtc_setup_lm_bounds() by skipping this part of the atomic check if dpu_encoder_virt_mode_set() hasn't been called yet. This fixes an UBSAN warning: UBSAN: Undefined behaviour in drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c:860:31 division by zero CPU: 7 PID: 409 Comm: frecon Tainted: G S 5.4.31 #128 Hardware name: Google Trogdor (rev0) (DT) Call trace: dump_backtrace+0x0/0x14c show_stack+0x20/0x2c dump_stack+0xa0/0xd8 __ubsan_handle_divrem_overflow+0xec/0x110 dpu_crtc_atomic_check+0x97c/0x9d4 drm_atomic_helper_check_planes+0x160/0x1c8 drm_atomic_helper_check+0x54/0xbc drm_atomic_check_only+0x6a8/0x880 drm_atomic_commit+0x20/0x5c drm_atomic_helper_set_config+0x98/0xa0 drm_mode_setcrtc+0x308/0x5dc drm_ioctl_kernel+0x9c/0x114 drm_ioctl+0x2ac/0x4b0 drm_compat_ioctl+0xe8/0x13c __arm64_compat_sys_ioctl+0x184/0x324 el0_svc_common+0xa4/0x154 el0_svc_compat_handler+0x Cc: Abhinav Kumar <abhinavk@codeaurora.org> Cc: Jeykumar Sankaran <jsanka@codeaurora.org> Cc: Jordan Crouse <jcrouse@codeaurora.org> Cc: Sean Paul <seanpaul@chromium.org> Fixes: 25fdd5933e ("drm/msm: Add SDM845 DPU support") Signed-off-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org> Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Signed-off-by: Rob Clark <robdclark@chromium.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2020-10-29 09:57:39 +01:00
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dpu1	drm/msm: Avoid div-by-zero in dpu_crtc_atomic_check()	2020-10-29 09:57:39 +01:00
mdp4	drm: msm: mdp4: Adjust indentation in mdp4_dsi_encoder_enable	2020-02-11 04:35:45 -08:00
mdp5	drm/msm/mdp5: Fix mdp5_init error path for failed mdp5_kms allocation	2020-06-24 17:50:29 +02:00
mdp_common.xml.h	drm/msm: update generated headers	2018-08-10 18:49:18 -04:00
mdp_format.c	drm/msm: remove unlikely() from WARN_ON() conditions	2019-09-04 08:42:45 -07:00
mdp_kms.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234	2019-06-19 17:09:07 +02:00
mdp_kms.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234	2019-06-19 17:09:07 +02:00