From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 729D42EC57C for ; Mon, 8 Dec 2025 15:58:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765209496; cv=none; b=VzhLR6bjL3GdeP5D81YQ3LN5O6SBVdwtCR8zr/0APeq1KURxSKrI2Zl0gBOSTvgDmQQnrOI7Drz3yhQeJX4eVXdIxk9OSpwyjJSexNo5hqk9iTVCiAwbA4LiysxCHbyNw6g74Cppuk9CKkHprCBK6qrYN2SlU+qB+JnpI4S++Ro= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765209496; c=relaxed/simple; bh=JGggKbleudk8lA+aNo1n/Ix7aeL+ih6dJN61Aky6LOQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=DFQIG4duyHpcjz4hroO5X0iZnQGtguqXLPQB91HU9YupnR8o8yGWnDiRiQ5mEVUlTA6OhWpLasjbxCgZkywNUCiCOATHgel7ZNcg4mGGoPLZ39Wvy40FdNELCKwGl45rxEk/aNDclS9gGNCzkrnwPVttyOfDbFvbWQHEjz4lDkU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=WEse7F2R; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=89+upyCI; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="WEse7F2R"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="89+upyCI" Date: Mon, 8 Dec 2025 16:58:11 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1765209492; 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: in-reply-to:in-reply-to:references:references; bh=wWpRDQ+aJBoo+jjV3aArFLZnIZH47Ly+oWJzHnx6VvQ=; b=WEse7F2RWv3dVLtQfUAXFhWV7nWfrXi1t1nCKMw3Bdbc0T8FfjI2yMuudlaIi9MtfSLdgS uOcOs6qikKzy/cuQ2drVPhh9yIOw6x83runoTqr9lgVJZrGYeK3E8CbJl63Nijz9FiJYh6 OlGS572vQ2o+p/1ihL7wpHmXCo3SSaKWICe8Z5EJQhfJjS9k+qixRbkenS+az38jAr72N0 tQJTL7/cQE6GJSRz04NKyFGRI7ZJ/il67MHC///Rl7EXblg5vxKAGfev3Yfe8BTStfCKMC +F7GqotNWY+GtwoAQQV7plko/Zk0SfwWBDcw28pjc2ClHfwQNbtypDR6kYPRAg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1765209492; 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: in-reply-to:in-reply-to:references:references; bh=wWpRDQ+aJBoo+jjV3aArFLZnIZH47Ly+oWJzHnx6VvQ=; b=89+upyCIhYXdVmjIuKhRYRIU7U4Rxfsm/R6xRE+/fRse3rP9PXfnysBw2IQ/U8Ov7YQ8oo LDzHiYrOc3iqawAA== From: Sebastian Andrzej Siewior To: Michael Schanne Cc: linux-rt-users@vger.kernel.org Subject: Re: Random lockups with i915 driver enabled Message-ID: <20251208155811.Gb4m8Z9J@linutronix.de> References: Precedence: bulk X-Mailing-List: linux-rt-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On 2025-12-03 16:23:01 [-0500], Michael Schanne wrote: > Hi, Hi, > Can anyone suggest any debug techniques to nail down root cause when > the next lockup occurs? Or are there any potential i915 fixes I could > try out? An 8250-UART would be probably help. Does lockdep (CONFIG_PROVE_LOCKING) and/ or CONFIG_DEBUG_ATOMIC_SLEEP complain? Can you setup pstore and use it for locking? Does your BIOS reset your memory on reset? If not, and you can force a reset in the lockup case, you could try to stuff some information into the tracing buffer. See https://docs.kernel.org/trace/debugging.html#persistent-buffers-across-boots Can you try to use the XE driver instead of i915? > Hardware: Intel i5-6500TE quad core CPU (Skylake), 16 GB RAM > > Thanks, > Mike Sebastian