From 4ea11e83083ae9c2fc650e4ffb352ea23c701b98 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Wed, 22 May 2024 17:12:59 +0200 Subject: [PATCH] 6.9-stable patches added patches: drm-amd-display-fix-division-by-zero-in-setup_dsc_config.patch --- ...division-by-zero-in-setup_dsc_config.patch | 61 +++++++++++++++++++ queue-6.9/series | 1 + 2 files changed, 62 insertions(+) create mode 100644 queue-6.9/drm-amd-display-fix-division-by-zero-in-setup_dsc_config.patch diff --git a/queue-6.9/drm-amd-display-fix-division-by-zero-in-setup_dsc_config.patch b/queue-6.9/drm-amd-display-fix-division-by-zero-in-setup_dsc_config.patch new file mode 100644 index 00000000000..82940b9c393 --- /dev/null +++ b/queue-6.9/drm-amd-display-fix-division-by-zero-in-setup_dsc_config.patch @@ -0,0 +1,61 @@ +From 130afc8a886183a94cf6eab7d24f300014ff87ba Mon Sep 17 00:00:00 2001 +From: Jose Fernandez +Date: Mon, 22 Apr 2024 08:35:44 -0600 +Subject: drm/amd/display: Fix division by zero in setup_dsc_config + +From: Jose Fernandez + +commit 130afc8a886183a94cf6eab7d24f300014ff87ba upstream. + +When slice_height is 0, the division by slice_height in the calculation +of the number of slices will cause a division by zero driver crash. This +leaves the kernel in a state that requires a reboot. This patch adds a +check to avoid the division by zero. + +The stack trace below is for the 6.8.4 Kernel. I reproduced the issue on +a Z16 Gen 2 Lenovo Thinkpad with a Apple Studio Display monitor +connected via Thunderbolt. The amdgpu driver crashed with this exception +when I rebooted the system with the monitor connected. + +kernel: ? die (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:434 arch/x86/kernel/dumpstack.c:447) +kernel: ? do_trap (arch/x86/kernel/traps.c:113 arch/x86/kernel/traps.c:154) +kernel: ? setup_dsc_config (drivers/gpu/drm/amd/amdgpu/../display/dc/dsc/dc_dsc.c:1053) amdgpu +kernel: ? do_error_trap (./arch/x86/include/asm/traps.h:58 arch/x86/kernel/traps.c:175) +kernel: ? setup_dsc_config (drivers/gpu/drm/amd/amdgpu/../display/dc/dsc/dc_dsc.c:1053) amdgpu +kernel: ? exc_divide_error (arch/x86/kernel/traps.c:194 (discriminator 2)) +kernel: ? setup_dsc_config (drivers/gpu/drm/amd/amdgpu/../display/dc/dsc/dc_dsc.c:1053) amdgpu +kernel: ? asm_exc_divide_error (./arch/x86/include/asm/idtentry.h:548) +kernel: ? setup_dsc_config (drivers/gpu/drm/amd/amdgpu/../display/dc/dsc/dc_dsc.c:1053) amdgpu +kernel: dc_dsc_compute_config (drivers/gpu/drm/amd/amdgpu/../display/dc/dsc/dc_dsc.c:1109) amdgpu + +After applying this patch, the driver no longer crashes when the monitor +is connected and the system is rebooted. I believe this is the same +issue reported for 3113. + +Reviewed-by: Rodrigo Siqueira +Signed-off-by: Jose Fernandez +Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3113 +Signed-off-by: Rodrigo Siqueira +Signed-off-by: Alex Deucher +Cc: "Limonciello, Mario" +Signed-off-by: Greg Kroah-Hartman +--- + drivers/gpu/drm/amd/display/dc/dsc/dc_dsc.c | 7 ++++++- + 1 file changed, 6 insertions(+), 1 deletion(-) + +--- a/drivers/gpu/drm/amd/display/dc/dsc/dc_dsc.c ++++ b/drivers/gpu/drm/amd/display/dc/dsc/dc_dsc.c +@@ -1055,7 +1055,12 @@ static bool setup_dsc_config( + if (!is_dsc_possible) + goto done; + +- dsc_cfg->num_slices_v = pic_height/slice_height; ++ if (slice_height > 0) { ++ dsc_cfg->num_slices_v = pic_height / slice_height; ++ } else { ++ is_dsc_possible = false; ++ goto done; ++ } + + if (target_bandwidth_kbps > 0) { + is_dsc_possible = decide_dsc_target_bpp_x16( diff --git a/queue-6.9/series b/queue-6.9/series index fa1d8a0a850..811dd41d717 100644 --- a/queue-6.9/series +++ b/queue-6.9/series @@ -1,3 +1,4 @@ bluetooth-btusb-fix-the-patch-for-mt7920-the-affected-to-mt7921.patch wifi-iwlwifi-use-request_module_nowait.patch cpufreq-amd-pstate-fix-the-highest-frequency-issue-which-limits-performance.patch +drm-amd-display-fix-division-by-zero-in-setup_dsc_config.patch -- 2.47.2