From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id ADB18EFB81C for ; Tue, 24 Feb 2026 16:59:09 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A9AFB10E5EA; Tue, 24 Feb 2026 16:59:07 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; secure) header.d=linutronix.de header.i=@linutronix.de header.b="lnzJEWV5"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="J7lyvhNv"; dkim-atps=neutral Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0B97810E5E8; Tue, 24 Feb 2026 16:59:06 +0000 (UTC) Date: Tue, 24 Feb 2026 17:59:03 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1771952344; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6Iy7ZEO55Jhhl31ZvbYVjantUPH52WNb/3cgiUFVx5I=; b=lnzJEWV5mu7cDRXITe5q4AvyphtfzSvJwT/0379YgIYtVOvqpoqd7Drhqi3PJJKkeK9r9p FtGyKAlqeE7Dpv6Xo2LvTPY0BwjWYaao4ydd78DQiJsEafcbG+4pi5pxVcFwjrDUmA4T4B EVIYGp5Vt68qmKUbXupmVdss2frhTQwu52Becc+agtFWApgYqjhlX0EVJTZ3VzLn+a8MES dgJCQMGyWiILwHz9xdxfJnJsW0jTGSqKtKP8WVHM/VqwQXlmJE1I+wNV7CxTw+GcNF7XK1 xnRIr+HKgxjdmPkmwpWRN/wnEF2QiW8TWNs3ty5UlhhLY+c6bKeqA3qk0a9Smg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1771952344; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6Iy7ZEO55Jhhl31ZvbYVjantUPH52WNb/3cgiUFVx5I=; b=J7lyvhNvXOl1NGoA1Ee/0QYdZ0Coz4zSeS0uPmrfAKFwb+apDoDo8nxc/z1RpKhqRODlf2 +qM+3vQ7i/Dp9+Dg== From: Sebastian Andrzej Siewior To: Maarten Lankhorst Cc: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-rt-devel@lists.linux.dev, dri-devel@lists.freedesktop.org Subject: Re: [i915-rt v6 00/24] drm/i915/display: All patches to make PREEMPT_RT work on i915 + xe. Message-ID: <20260224165903.2mn24oQy@linutronix.de> References: <20260220083657.28815-26-dev@lankhorst.se> <20260224162703.Q_taYjEC@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <20260224162703.Q_taYjEC@linutronix.de> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On 2026-02-24 17:27:03 [+0100], To Maarten Lankhorst wrote: >=20 > There is nothing else, that popped up. So far no objections from my side > ;) Thank you. different HW. | i915 0000:00:02.0: [drm] *ERROR* [CRTC:170:pipe A] flip_done timed out | rcu: INFO: rcu_preempt self-detected stall on CPU | rcu: 7-....: (1 GPs behind) idle=3Dbc04/1/0x4000000000000000 softirq=3D= 0/0 fqs=3D3084 rcuc=3D6502 jiffies(starved) | rcu: (t=3D6500 jiffies g=3D46813 q=3D13322 ncpus=3D8) | CPU: 7 UID: 0 PID: 12616 Comm: irq/182-i915 Tainted: G U E = 7.0.0-rc1-lockdep+ #2 PREEMPT_{RT,(lazy)} | Tainted: [U]=3DUSER, [E]=3DUNSIGNED_MODULE | Hardware name: LENOVO 20TD00GLGE/20TD00GLGE, BIOS R1EET64W(1.64 ) 03/18/= 2025 | RIP: 0010:intel_context_remove_breadcrumbs+0x14a/0x1a0 [i915] | Code: 00 00 48 8b 50 70 b8 ff ff ff ff f0 41 0f c1 06 83 f8 01 74 58 85 = c0 7f 11 be 03 00 00 00 4c 89 f7 e8 fa 65 db e7 eb 02 f3 90 <41> 8b 84 24 a= 0 00 00 00 85 c0 75 f2 48 83 c4 08 5b 5d 41 5c 41 5d | RSP: 0018:ffffd2aa007d7c48 EFLAGS: 00000202 | RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000000001 | RDX: ffffffffc282ab20 RSI: ffffffffab33e33f RDI: 00000000ffffffff | RBP: ffff8f1247401680 R08: 0000000000000001 R09: 0000000000000000 | R10: 0000000000000000 R11: 0000000000000000 R12: ffff8f104f3b6200 | R13: ffff8f12474017e0 R14: ffff8f1247401798 R15: ffff8f119e89e3a8 | FS: 0000000000000000(0000) GS:ffff8f140318b000(0000) knlGS:000000000000= 0000 | CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 | CR2: 00007f5409dc6000 CR3: 000000029ea56006 CR4: 0000000000f72ef0 | PKRU: 55555554 | Call Trace: | | __execlists_schedule_out+0x1a6/0x340 [i915] | execlists_submission_tasklet+0x178/0x1bb0 [i915] | tasklet_action_common+0x1e9/0x410 | handle_softirqs.isra.0+0xbd/0x3f0 | __local_bh_enable_ip+0xe0/0x170 | irq_forced_thread_fn+0x41/0x50 | irq_thread+0x20d/0x360 | kthread+0x103/0x140 | ret_from_fork+0x34d/0x480 | ret_from_fork_asm+0x1a/0x30 | It seems to be always stuck in intel_context_remove_breadcrumbs. and top shows | 42 root 20 0 0 0 0 R 100,0 0,0 3:21.62 kso= ftirqd/2 | 12616 root -51 0 0 0 0 R 100,0 0,0 3:34.61 irq= /182-i915 seems busy. The NMI backtrace reports always intel_context_remove_breadcrumbs() on CPU, don't see the irq handler. This one I can reproduce while opening a browser and surfing a bit. Let me try step by step without lockdep, without RT and maybe just play v7.0-rc1 to figure out where this is from=E2=80=A6 Sebastian