From 3f65b1e2f424f44585bd701024a3bfd0b1e0ade2 Mon Sep 17 00:00:00 2001 From: Kuogee Hsieh Date: Tue, 26 Apr 2022 14:12:14 -0700 Subject: drm/msm/dp: remove fail safe mode related code Current DP driver implementation has adding safe mode done at dp_hpd_plug_handle() which is expected to be executed under event thread context. However there is possible circular locking happen (see blow stack trace) after edp driver call dp_hpd_plug_handle() from dp_bridge_enable() which is executed under drm_thread context. After review all possibilities methods and as discussed on https://patchwork.freedesktop.org/patch/483155/, supporting EDID compliance tests in the driver is quite hacky. As seen with other vendor drivers, supporting these will be much easier with IGT. Hence removing all the related fail safe code for it so that no possibility of circular lock will happen. Reviewed-by: Stephen Boyd Reviewed-by: Douglas Anderson Reviewed-by: Dmitry Baryshkov ====================================================== WARNING: possible circular locking dependency detected 5.15.35-lockdep #6 Tainted: G W ------------------------------------------------------ frecon/429 is trying to acquire lock: ffffff808dc3c4e8 (&dev->mode_config.mutex){+.+.}-{3:3}, at: dp_panel_add_fail_safe_mode+0x4c/0xa0 but task is already holding lock: ffffff808dc441e0 (&kms->commit_lock[i]){+.+.}-{3:3}, at: lock_crtcs+0xb4/0x124 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&kms->commit_lock[i]){+.+.}-{3:3}: __mutex_lock_common+0x174/0x1a64 mutex_lock_nested+0x98/0xac lock_crtcs+0xb4/0x124 msm_atomic_commit_tail+0x330/0x748 commit_tail+0x19c/0x278 drm_atomic_helper_commit+0x1dc/0x1f0 drm_atomic_commit+0xc0/0xd8 drm_atomic_helper_set_config+0xb4/0x134 drm_mode_setcrtc+0x688/0x1248 drm_ioctl_kernel+0x1e4/0x338 drm_ioctl+0x3a4/0x684 __arm64_sys_ioctl+0x118/0x154 invoke_syscall+0x78/0x224 el0_svc_common+0x178/0x200 do_el0_svc+0x94/0x13c el0_svc+0x5c/0xec el0t_64_sync_handler+0x78/0x108 el0t_64_sync+0x1a4/0x1a8 -> #2 (crtc_ww_class_mutex){+.+.}-{3:3}: __mutex_lock_common+0x174/0x1a64 ww_mutex_lock+0xb8/0x278 modeset_lock+0x304/0x4ac drm_modeset_lock+0x4c/0x7c drmm_mode_config_init+0x4a8/0xc50 msm_drm_init+0x274/0xac0 msm_drm_bind+0x20/0x2c try_to_bring_up_master+0x3dc/0x470 __component_add+0x18c/0x3c0 component_add+0x1c/0x28 dp_display_probe+0x954/0xa98 platform_probe+0x124/0x15c really_probe+0x1b0/0x5f8 __driver_probe_device+0x174/0x20c driver_probe_device+0x70/0x134 __device_attach_driver+0x130/0x1d0 bus_for_each_drv+0xfc/0x14c __device_attach+0x1bc/0x2bc device_initial_probe+0x1c/0x28 bus_probe_device+0x94/0x178 deferred_probe_work_func+0x1a4/0x1f0 process_one_work+0x5d4/0x9dc worker_thread+0x898/0xccc kthread+0x2d4/0x3d4 ret_from_fork+0x10/0x20 -> #1 (crtc_ww_class_acquire){+.+.}-{0:0}: ww_acquire_init+0x1c4/0x2c8 drm_modeset_acquire_init+0x44/0xc8 drm_helper_probe_single_connector_modes+0xb0/0x12dc drm_mode_getconnector+0x5dc/0xfe8 drm_ioctl_kernel+0x1e4/0x338 drm_ioctl+0x3a4/0x684 __arm64_sys_ioctl+0x118/0x154 invoke_syscall+0x78/0x224 el0_svc_common+0x178/0x200 do_el0_svc+0x94/0x13c el0_svc+0x5c/0xec el0t_64_sync_handler+0x78/0x108 el0t_64_sync+0x1a4/0x1a8 -> #0 (&dev->mode_config.mutex){+.+.}-{3:3}: __lock_acquire+0x2650/0x672c lock_acquire+0x1b4/0x4ac __mutex_lock_common+0x174/0x1a64 mutex_lock_nested+0x98/0xac dp_panel_add_fail_safe_mode+0x4c/0xa0 dp_hpd_plug_handle+0x1f0/0x280 dp_bridge_enable+0x94/0x2b8 drm_atomic_bridge_chain_enable+0x11c/0x168 drm_atomic_helper_commit_modeset_enables+0x500/0x740 msm_atomic_commit_tail+0x3e4/0x748 commit_tail+0x19c/0x278 drm_atomic_helper_commit+0x1dc/0x1f0 drm_atomic_commit+0xc0/0xd8 drm_atomic_helper_set_config+0xb4/0x134 drm_mode_setcrtc+0x688/0x1248 drm_ioctl_kernel+0x1e4/0x338 drm_ioctl+0x3a4/0x684 __arm64_sys_ioctl+0x118/0x154 invoke_syscall+0x78/0x224 el0_svc_common+0x178/0x200 do_el0_svc+0x94/0x13c el0_svc+0x5c/0xec el0t_64_sync_handler+0x78/0x108 el0t_64_sync+0x1a4/0x1a8 Changes in v2: -- re text commit title -- remove all fail safe mode Changes in v3: -- remove dp_panel_add_fail_safe_mode() from dp_panel.h -- add Fixes Changes in v5: -- to=dianders@chromium.org Changes in v6: -- fix Fixes commit ID Fixes: 8b2c181e3dcf ("drm/msm/dp: add fail safe mode outside of event_mutex context") Reported-by: Douglas Anderson Signed-off-by: Kuogee Hsieh Link: https://lore.kernel.org/r/1651007534-31842-1-git-send-email-quic_khsieh@quicinc.com Signed-off-by: Rob Clark --- drivers/gpu/drm/msm/dp/dp_display.c | 6 ------ drivers/gpu/drm/msm/dp/dp_panel.c | 11 ----------- drivers/gpu/drm/msm/dp/dp_panel.h | 1 - 3 files changed, 18 deletions(-) diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c index a42732b67349..178b774a5fbd 100644 --- a/drivers/gpu/drm/msm/dp/dp_display.c +++ b/drivers/gpu/drm/msm/dp/dp_display.c @@ -580,12 +580,6 @@ static int dp_hpd_plug_handle(struct dp_display_private *dp, u32 data) dp->dp_display.connector_type, state); mutex_unlock(&dp->event_mutex); - /* - * add fail safe mode outside event_mutex scope - * to avoid potiential circular lock with drm thread - */ - dp_panel_add_fail_safe_mode(dp->dp_display.connector); - /* uevent will complete connection part */ return 0; }; diff --git a/drivers/gpu/drm/msm/dp/dp_panel.c b/drivers/gpu/drm/msm/dp/dp_panel.c index 26c3653c99ec..26f4b6959c31 100644 --- a/drivers/gpu/drm/msm/dp/dp_panel.c +++ b/drivers/gpu/drm/msm/dp/dp_panel.c @@ -151,15 +151,6 @@ static int dp_panel_update_modes(struct drm_connector *connector, return rc; } -void dp_panel_add_fail_safe_mode(struct drm_connector *connector) -{ - /* fail safe edid */ - mutex_lock(&connector->dev->mode_config.mutex); - if (drm_add_modes_noedid(connector, 640, 480)) - drm_set_preferred_mode(connector, 640, 480); - mutex_unlock(&connector->dev->mode_config.mutex); -} - int dp_panel_read_sink_caps(struct dp_panel *dp_panel, struct drm_connector *connector) { @@ -215,8 +206,6 @@ int dp_panel_read_sink_caps(struct dp_panel *dp_panel, rc = -ETIMEDOUT; goto end; } - - dp_panel_add_fail_safe_mode(connector); } if (panel->aux_cfg_update_done) { diff --git a/drivers/gpu/drm/msm/dp/dp_panel.h b/drivers/gpu/drm/msm/dp/dp_panel.h index 99739ea679a7..9023e5bb4b8b 100644 --- a/drivers/gpu/drm/msm/dp/dp_panel.h +++ b/drivers/gpu/drm/msm/dp/dp_panel.h @@ -59,7 +59,6 @@ int dp_panel_init_panel_info(struct dp_panel *dp_panel); int dp_panel_deinit(struct dp_panel *dp_panel); int dp_panel_timing_cfg(struct dp_panel *dp_panel); void dp_panel_dump_regs(struct dp_panel *dp_panel); -void dp_panel_add_fail_safe_mode(struct drm_connector *connector); int dp_panel_read_sink_caps(struct dp_panel *dp_panel, struct drm_connector *connector); u32 dp_panel_get_mode_bpp(struct dp_panel *dp_panel, u32 mode_max_bpp, -- cgit v1.2.3 From aafa025c76dcc7d1a8c8f0bdefcbe4eb480b2f6a Mon Sep 17 00:00:00 2001 From: Javier Martinez Canillas Date: Mon, 2 May 2022 15:50:14 +0200 Subject: fbdev: Make fb_release() return -ENODEV if fbdev was unregistered A reference to the framebuffer device struct fb_info is stored in the file private data, but this reference could no longer be valid and must not be accessed directly. Instead, the file_fb_info() accessor function must be used since it does sanity checking to make sure that the fb_info is valid. This can happen for example if the registered framebuffer device is for a driver that just uses a framebuffer provided by the system firmware. In that case, the fbdev core would unregister the framebuffer device when a real video driver is probed and ask to remove conflicting framebuffers. The bug has been present for a long time but commit 27599aacbaef ("fbdev: Hot-unplug firmware fb devices on forced removal") unmasked it since the fbdev core started unregistering the framebuffers' devices associated. Fixes: 27599aacbaef ("fbdev: Hot-unplug firmware fb devices on forced removal") Reported-by: Maxime Ripard Reported-by: Junxiao Chang Signed-off-by: Javier Martinez Canillas Reviewed-by: Thomas Zimmermann Link: https://patchwork.freedesktop.org/patch/msgid/20220502135014.377945-1-javierm@redhat.com --- drivers/video/fbdev/core/fbmem.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index a6bb0e438216..97eb0dee411c 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1434,7 +1434,10 @@ fb_release(struct inode *inode, struct file *file) __acquires(&info->lock) __releases(&info->lock) { - struct fb_info * const info = file->private_data; + struct fb_info * const info = file_fb_info(file); + + if (!info) + return -ENODEV; lock_fb_info(info); if (info->fbops->fb_release) -- cgit v1.2.3 From 841e512ffb64898db6322c0619f6bbc41266d86f Mon Sep 17 00:00:00 2001 From: Fabien Parent Date: Tue, 26 Apr 2022 16:15:36 +0200 Subject: drm/bridge: ite-it6505: add missing Kconfig option select The IT6505 is using functions provided by the DRM_DP_HELPER driver. In order to avoid having the bridge enabled but the helper disabled, let's add a select in order to be sure that the DP helper functions are always available. Fixes: b5c84a9edcd4 ("drm/bridge: add it6505 driver") Signed-off-by: Fabien Parent Reviewed-by: Neil Armstrong Signed-off-by: Neil Armstrong Link: https://patchwork.freedesktop.org/patch/msgid/20220426141536.274727-1-fparent@baylibre.com --- drivers/gpu/drm/bridge/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig index 007e5a282f67..2145b08f9534 100644 --- a/drivers/gpu/drm/bridge/Kconfig +++ b/drivers/gpu/drm/bridge/Kconfig @@ -78,6 +78,7 @@ config DRM_ITE_IT6505 tristate "ITE IT6505 DisplayPort bridge" depends on OF select DRM_KMS_HELPER + select DRM_DP_HELPER select EXTCON help ITE IT6505 DisplayPort bridge chip driver. -- cgit v1.2.3 From 19965d8259fdabc6806da92adda49684f5bcbec5 Mon Sep 17 00:00:00 2001 From: Marek Marczykowski-Górecki Date: Wed, 27 Apr 2022 01:57:15 +0200 Subject: drm/amdgpu: do not use passthrough mode in Xen dom0 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit While technically Xen dom0 is a virtual machine too, it does have access to most of the hardware so it doesn't need to be considered a "passthrough". Commit b818a5d37454 ("drm/amdgpu/gmc: use PCI BARs for APUs in passthrough") changed how FB is accessed based on passthrough mode. This breaks amdgpu in Xen dom0 with message like this: [drm:dc_dmub_srv_wait_idle [amdgpu]] *ERROR* Error waiting for DMUB idle: status=3 While the reason for this failure is unclear, the passthrough mode is not really necessary in Xen dom0 anyway. So, to unbreak booting affected kernels, disable passthrough mode in this case. Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1985 Fixes: b818a5d37454 ("drm/amdgpu/gmc: use PCI BARs for APUs in passthrough") Signed-off-by: Marek Marczykowski-Górecki Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c index a025f080aa6a..5e3756643da3 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c @@ -24,6 +24,7 @@ #include #include +#include #include "amdgpu.h" #include "amdgpu_ras.h" @@ -710,7 +711,8 @@ void amdgpu_detect_virtualization(struct amdgpu_device *adev) adev->virt.caps |= AMDGPU_SRIOV_CAPS_ENABLE_IOV; if (!reg) { - if (is_virtual_machine()) /* passthrough mode exclus sriov mod */ + /* passthrough mode exclus sriov mod */ + if (is_virtual_machine() && !xen_initial_domain()) adev->virt.caps |= AMDGPU_PASSTHROUGH_MODE; } -- cgit v1.2.3 From 3dfe85fa87b2a26bdbd292b66653bba065cf9941 Mon Sep 17 00:00:00 2001 From: Harry Wentland Date: Tue, 19 Apr 2022 13:03:12 -0400 Subject: drm/amd/display: Avoid reading audio pattern past AUDIO_CHANNELS_COUNT A faulty receiver might report an erroneous channel count. We should guard against reading beyond AUDIO_CHANNELS_COUNT as that would overflow the dpcd_pattern_period array. Signed-off-by: Harry Wentland Reviewed-by: Alex Deucher Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org --- drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c index 22dabe596dfc..95b5b5bfa1ff 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c @@ -4440,7 +4440,7 @@ static void dp_test_get_audio_test_data(struct dc_link *link, bool disable_video &dpcd_pattern_type.value, sizeof(dpcd_pattern_type)); - channel_count = dpcd_test_mode.bits.channel_count + 1; + channel_count = min(dpcd_test_mode.bits.channel_count + 1, AUDIO_CHANNELS_COUNT); // read pattern periods for requested channels when sawTooth pattern is requested if (dpcd_pattern_type.value == AUDIO_TEST_PATTERN_SAWTOOTH || -- cgit v1.2.3