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 2F70D40F724; Fri, 25 Sep 2026 06:14:15 +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=1790316857; cv=none; b=S1R6A3Yn3c6gd8gG7TIWQenwztLdKr8mAxpEt6pPNSzW1ODTzDft2Dj0O7+ucj4GAzgz6SjehSql57QAJg/EcIuNNLvuJUAll89+nLpjUllOLs0AqI0F2XFbclx4Oh/HDqZriCl7Pn7a7vt748v/gHQs+JNNmRMJREMxroQnq7A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790316857; c=relaxed/simple; bh=zJPVYut3caqV+BupQglYKFwx8NCPvWAjqyqRdOTUaHo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=sDDDV+zCdgr35DWNHPUxNwEkdidXmNBwUBbuz6wi/GDRb23fGrmXKpG5P8izsBWEQ8x/TvzrEqkgasydzjGOzEeFzVTH2narCXsroGqr9clOfS/GT6lYHAzJdE4OlJBQK6QDD4szTBAJdj0LSNOjyhHGPOfcQ7OooaCIUlwz6JM= 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=UL5H20c8; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=b648NJ06; 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="UL5H20c8"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="b648NJ06" Date: Fri, 25 Sep 2026 08:14:12 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1790316853; 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=+9t0kxTYJaraIMrfEqcVi2n0bhKkI1NpUKQYTTJwJiA=; b=UL5H20c8pe0C3qusv5XX1mo+I4zBXKKS320j1shCqc7ov+H8lDM7SXQ/4LMT10xrtAQxXX vO6BHJb1Qll7ZKK5bBFjD9HoNAMaeed8Z1PvImisuq5o8cobKA4WCJKqdQh8Bm8wfRsvKL SDhapMikKeY+ccjQUHKD8CyjCQtZ5GiJK/NBo1Az9zCuLh5RcFo9UqElTT2HPHepA7AC1W 8VQVxGg3DRSnOiEBjXrAYLeMC15NszklfuUjZg/xwkfZuRq6xKFbwZKZ0UjXHHJPqgO2aF pMga251v2F5bPbmTHOLVLQjph06IY9lSK50+YDVeim2pJLfX+eRL99x7cIQZ5g== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1790316853; 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=+9t0kxTYJaraIMrfEqcVi2n0bhKkI1NpUKQYTTJwJiA=; b=b648NJ069Sf+pwW33BuNO6uws6R1OlRZBUaKyGv3pPXp/Xt80RMmolfwQ0Uk8220YySjsf vFIGXzcHKp4EJ8AQ== From: Sebastian Andrzej Siewior To: Prashant Singh Cc: Ard Biesheuvel , "Luis Claudio R . Goncalves" , Steve McIntyre <93sam@debian.org>, Jeremy Kerr , Clark Williams , Steven Rostedt , linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, Jonathan Corbet , linux-doc@vger.kernel.org, linux-rt-devel@lists.linux.dev Subject: Re: [PATCH v2] efivarfs: add nostatfs mount option to skip QueryVariableInfo() Message-ID: <20260925061412.Ly5-sosB@linutronix.de> References: <20260919044124.8268-1-singhpra@juniper.net> <20260924111913.GN3447081@tack.einval.com> <0d23d4f2-b5b8-47c3-a676-f6ec72ecf45d@app.fastmail.com> <20260925014528.2015-1-singhpra@juniper.net> Precedence: bulk X-Mailing-List: linux-kernel@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: <20260925014528.2015-1-singhpra@juniper.net> On 2026-09-24 18:45:28 [-0700], Prashant Singh wrote: > On Thu, 24 Sep 2026, at 13:59, Ard Biesheuvel wrote: > > On Thu, 24 Sep 2026, at 13:36, Luis Claudio R. Goncalves wrote: > >> In this case, corroborating with Sashiko findings, it is necessary to > >> have a way to override that default in kernels with PREEMPT_RT enabled. > >> To be used where this is required for firmware updates. > > > > Indeed. > > Agreed -- and thanks Luis and Steve for catching the fwupd impact. > > For v3 I'll make the option a negatable flag: "nostatfs" skips > QueryVariableInfo() (and remains the default on PREEMPT_RT), while > "statfs" forces reporting back on. So on an RT kernel, mounting efivarfs > with -o statfs restores the free-space reporting that fwupd needs for > KEK/DB/DBX updates, while the default still avoids the preempt-disabled > firmware call. Having -o remount,statfs=on and remount,statfs=off working would probably improve the situation. > I'll send v3 with that change shortly. > > Thanks, > Prashant Sebastian