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 0C97B446060 for ; Tue, 25 Aug 2026 12:44:58 +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=1787661902; cv=none; b=S6Iv0arBZM/U/WG0BLk7rEKNsb7xBf7eq/TfCR/zUIVoJPu4DSaMrLhGNRd6cQ5UCMoW2AabsGNW3rEOihX/TLWCxRfcPsR0YJ5J+igPwX3d3dRYfuN4PIHsM2S1K2R2DrLkPWUcbBHb9BXjKb95B0ZrEzRsAsoA9N/uIFxYWqo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787661902; c=relaxed/simple; bh=2WBa5yL+7vSgKX+cxpFmOw86WRi1VKisk1YblekmpM4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QHPffxXe9xLPpwyPEKFKQMHWDaesgXBU7kqk9BCx/oJB8sIubLC19eXMuxiLY02KyFPSqZSDol34R76ZxgH+0gZFTwD8ozQ7EtVZzC4hJbhmIblTmQCKXmnC41mCOPLuuNsC2Vb5cwfjaOMb4EOKAvw/KvyUr1U+ajN5tqOxtm0= 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=TqyaP5H5; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=/Q+SsUnk; 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="TqyaP5H5"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="/Q+SsUnk" Date: Tue, 25 Aug 2026 14:44:53 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1787661894; 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=hL0wB/AdivBKbKIpjc5ZJrroaiZ2UbAuMgPZt+oESDg=; b=TqyaP5H5MiRq5LvtqGxqBP2Dy6EKxCnx+uGxoHY2PZ4NBLuTm2nA7bEbVRhOK3mpxK8gLg JJDMDJiRiUeOpJ6gwWba/e2CdoHYbNYuq5Lvj0oWp1SdB/CPqMHb2G9C1EJ1dag6KBSPnL xrTG+Q90KrgHyC4yNcp8gmiHlmmftIk560UvNPPxQ+25EsliTFBB2zM0L5tfnT4wE0Yi7H n+JO9w2556IAEtUvp7fnP5K+NuIWy4Bg+aPGK/gt20tl2rqyQzcWXpITO1TDLci06Bg2nE WZ7IAG77gRgRxiAjA7aTuFDikj1BzUG6CSnWig68/ZUaBxn6OKeEk5f44+K+WA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1787661894; 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=hL0wB/AdivBKbKIpjc5ZJrroaiZ2UbAuMgPZt+oESDg=; b=/Q+SsUnk/JXO93T3zPJW1z6hTQdhNB3qPad/8fQnH8sJ653ch9QCk+dhWy01lrrsacDyBW 0VHUWw4Hv4XmKcDw== From: Sebastian Andrzej Siewior To: Chris Packham , Mike Schanne Cc: "gregkh@linuxfoundation.org" , LKML , "linux-rt-devel@lists.linux.dev" , linux-rt-users , Thomas Gleixner , Steven Rostedt , Todd Leitzel Subject: Re: [PATCH] uio: eliminate extraneous irq thread under CONFIG_PREEMPT_RT Message-ID: <20260825124453.INbPSgYf@linutronix.de> References: <20260819150611.xWELTqJ-@linutronix.de> <5943e7e5-9578-42a1-b693-d79f9eef88f0@alliedtelesis.co.nz> <20260820141222.gPkfKLpT@linutronix.de> Precedence: bulk X-Mailing-List: linux-rt-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20260820141222.gPkfKLpT@linutronix.de> On 2026-08-20 16:12:22 [+0200], To Chris Packham wrote: > > If so, you realize that uio_interrupt_handler() isn't called at all? Mike could you please post a patch which reverts f8a27dfa4b82d ("uio: use threaded interrupts") because - it breaks the threadirqs case including PREEMPT_RT - I doubt that it solved the reported problem because it does not invoke the primary handler of UIO at all because it gets overwritten to irq_nested_primary_handler(). As for the Chris case, I would suggest to check the IRQ for irq_settings_is_nested_thread() and then use request_threaded_irq(). Sebastian