From 08e3ed3ae56bf235e46b8d5d2e36ef1712f14285 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 3 Feb 2020 13:34:08 +0000 Subject: [PATCH] drm/i915/audio: Skip the cdclk modeset if no pipes attached MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit If the display is not driving any pipes, we cannot change the bclk and doing so risks chasing NULL pointers: <6> [278.907105] snd_hda_intel 0000:00:0e.0: DSP detected with PCI class/subclass/prog-if info 0x040100 <6> [278.909936] snd_hda_intel 0000:00:0e.0: bound 0000:00:02.0 (ops i915_audio_component_bind_ops [i915]) <7> [278.910078] i915 0000:00:02.0: [drm:intel_power_well_enable [i915]] enabling power well 2 <1> [278.910228] BUG: kernel NULL pointer dereference, address: 0000000000000080 <1> [278.910243] #PF: supervisor read access in kernel mode <1> [278.910251] #PF: error_code(0x0000) - not-present page <6> [278.910260] PGD 0 P4D 0 <4> [278.910267] Oops: 0000 [#1] PREEMPT SMP PTI <4> [278.910276] CPU: 0 PID: 5 Comm: kworker/0:0 Tainted: G U 5.5.0-CI-CI_DRM_7853+ #1 <4> [278.910289] Hardware name: Intel Corp. Geminilake/GLK RVP2 LP4SD (07), BIOS GELKRVPA.X64.0062.B30.1708222146 08/22/2017 <4> [278.910312] Workqueue: events azx_probe_work [snd_hda_intel] <4> [278.910327] RIP: 0010:__ww_mutex_lock.constprop.15+0x5e/0x1090 <4> [278.910338] Code: 75 88 be a7 03 00 00 65 48 8b 04 25 28 00 00 00 48 89 45 c8 31 c0 4c 89 c3 e8 5e b3 6d ff 44 8b 3d 2f 24 37 02 45 85 ff 75 0a <4d> 3b 6d 58 0f 85 3f 07 00 00 48 85 db 74 22 49 8b 95 80 00 00 00 <4> [278.910362] RSP: 0018:ffffc9000008bc10 EFLAGS: 00010246 <4> [278.910371] RAX: 0000000000000246 RBX: ffffc9000008bd30 RCX: 0000000000000001 <4> [278.910382] RDX: 0000000000000000 RSI: ffffffff82647c60 RDI: ffff88817b27d848 <4> [278.910393] RBP: ffffc9000008bcc0 R08: 0000000000000000 R09: 0000000000000001 <4> [278.910404] R10: ffffc9000008bce0 R11: 0000000000000000 R12: ffffffff8168f0fc <4> [278.910414] R13: 0000000000000028 R14: ffffc9000008bd60 R15: 0000000000000000 <4> [278.910425] FS: 0000000000000000(0000) GS:ffff88817bc00000(0000) knlGS:0000000000000000 <4> [278.910437] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4> [278.910446] CR2: 0000000000000080 CR3: 00000001650da000 CR4: 0000000000340ef0 <4> [278.910456] Call Trace: <4> [278.910468] ? mark_held_locks+0x49/0x70 <4> [278.910479] ? ww_mutex_lock+0x39/0x70 <4> [278.910487] ww_mutex_lock+0x39/0x70 <4> [278.910497] drm_modeset_lock+0x6c/0x120 <4> [278.910575] glk_force_audio_cdclk+0x7d/0x140 [i915] <4> [278.910656] i915_audio_component_get_power+0xf2/0x110 [i915] <4> [278.910673] snd_hdac_display_power+0x7d/0x120 [snd_hda_core] <4> [278.910686] azx_probe_work+0x88/0x7e0 [snd_hda_intel] v2: Reorder glk_force_audio_cdclk() parameters to fit in with the norm. Closes: https://gitlab.freedesktop.org/drm/intel/issues/1095 Signed-off-by: Chris Wilson Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20200203133408.187493-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/display/intel_audio.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_audio.c b/drivers/gpu/drm/i915/display/intel_audio.c index 13833a7a8f27..30fb7c887ff0 100644 --- a/drivers/gpu/drm/i915/display/intel_audio.c +++ b/drivers/gpu/drm/i915/display/intel_audio.c @@ -811,15 +811,13 @@ void intel_init_audio_hooks(struct drm_i915_private *dev_priv) } static int glk_force_audio_cdclk_commit(struct intel_atomic_state *state, + struct intel_crtc *crtc, bool enable) { - struct drm_i915_private *dev_priv = to_i915(state->base.dev); struct intel_cdclk_state *cdclk_state; - struct intel_crtc *crtc; int ret; /* need to hold at least one crtc lock for the global state */ - crtc = intel_get_crtc_for_pipe(dev_priv, PIPE_A); ret = drm_modeset_lock(&crtc->base.mutex, state->base.acquire_ctx); if (ret) return ret; @@ -843,8 +841,13 @@ static void glk_force_audio_cdclk(struct drm_i915_private *dev_priv, { struct drm_modeset_acquire_ctx ctx; struct drm_atomic_state *state; + struct intel_crtc *crtc; int ret; + crtc = intel_get_crtc_for_pipe(dev_priv, PIPE_A); + if (!crtc) + return; + drm_modeset_acquire_init(&ctx, 0); state = drm_atomic_state_alloc(&dev_priv->drm); if (drm_WARN_ON(&dev_priv->drm, !state)) @@ -853,7 +856,8 @@ static void glk_force_audio_cdclk(struct drm_i915_private *dev_priv, state->acquire_ctx = &ctx; retry: - ret = glk_force_audio_cdclk_commit(to_intel_atomic_state(state), enable); + ret = glk_force_audio_cdclk_commit(to_intel_atomic_state(state), crtc, + enable); if (ret == -EDEADLK) { drm_atomic_state_clear(state); drm_modeset_backoff(&ctx); -- 2.30.2