From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender4-of-o52.zoho.com (sender4-of-o52.zoho.com [136.143.188.52]) (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 3304A3FF892; Wed, 13 May 2026 12:15:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.52 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778674506; cv=pass; b=mMzOM0rJQ/e2LVa50Wgxi3ZFZDm7q17bN9xH+CcalOiyIFVhNMU6v0NQjR3Reg/xKwjBp9BvpofWVsR+Oa6IFfFBcHlnrUbANEreB2yazcU70LrtOmN6GVNMLBakN+XLgHEghmRyOXsX6JJSnQGZ742qHs0Zw+6/WERi9/3gdYU= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778674506; c=relaxed/simple; bh=suKrZx9WF1Eqg/NdqIGSgk1jONz+zU2yuOt46M6v/Oo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=YyFNcf/BqmPdCKgT1Rckso+sBy7HqzRrpcJQPeCvma6sDDaxav5WJiFvjJ0QHh0m7ayKovXp/PAfdj8Mnavux1PAxwXckt/SaXdi5x+7y1bh77p6sBdJbKQqEluW6SJZDTTzIodZKYHNYaujHpm6/u+7VUu0n/TslYNOplNoEYw= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=anirudhrb.com; spf=pass smtp.mailfrom=anirudhrb.com; dkim=pass (1024-bit key) header.d=anirudhrb.com header.i=anirudh@anirudhrb.com header.b=gFh9Mutg; arc=pass smtp.client-ip=136.143.188.52 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=anirudhrb.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=anirudhrb.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=anirudhrb.com header.i=anirudh@anirudhrb.com header.b="gFh9Mutg" ARC-Seal: i=1; a=rsa-sha256; t=1778674498; cv=none; d=zohomail.com; s=zohoarc; b=SwKmkQFRlm+csYrgQktKylPjF6I8SYZoRUYr8Ah/m8Y1lyHcQtrC32pC61/gJpjRkHedD2FGq9Xv4EQuiT9PGZawNzzFdDSV2XVSjmw9Dn+MmI7i9feNQQd9c4aJo4qsVS+J8750cY3DfT994lo9USLdohFNbRyQnXdpsEH0EOA= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1778674498; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=suKrZx9WF1Eqg/NdqIGSgk1jONz+zU2yuOt46M6v/Oo=; b=OuBqvGoDp7XumKlJFXkiIUo74FDbhoyxGfqvWBmFXeipKi8CNWNVoP0XX+bstA1ZmBOolrqMy1QSQiFTj1MLDL9/zSc/tHJNijWXdU0jxvI6hA5e6qYyngy5yH0Xdrm57qV2spLcTQr8+8P4gVGXs+lhZGJafLjMDS6kLy6o4yQ= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=anirudhrb.com; spf=pass smtp.mailfrom=anirudh@anirudhrb.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1778674498; s=zoho; d=anirudhrb.com; i=anirudh@anirudhrb.com; h=Date:Date:From:From:To:To:Cc:Cc:Subject:Subject:Message-ID:References:MIME-Version:Content-Type:Content-Transfer-Encoding:In-Reply-To:Message-Id:Reply-To; bh=suKrZx9WF1Eqg/NdqIGSgk1jONz+zU2yuOt46M6v/Oo=; b=gFh9MutgbeLM0FjJn71jM4Gt4nv2Kx22DB9y3TukHOtmhOuPK1gZd3bSVnX42lN5 Mld+So2vS2YFUFsIqSPX4lqIdCnVGAHipNq87Gv5iSDfd31AlAPJdkbv3V9j1NzxAs/ v3Ah/PWXKArddNiCcWTJOZwJyPOXqKkF5V6jbshE= Received: by mx.zohomail.com with SMTPS id 1778674495350171.1089952125758; Wed, 13 May 2026 05:14:55 -0700 (PDT) Date: Wed, 13 May 2026 12:14:49 +0000 From: Anirudh Rayabharam To: Stanislav Kinsburskii Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 08/18] mshv: Fix level-triggered check on uninitialized data Message-ID: <20260513-omniscient-enchanted-otter-dfd602@anirudhrb> References: <177816592843.21765.4364464279247150355.stgit@skinsburskii-cloud-desktop.internal.cloudapp.net> <177816862362.21765.11809618639989414561.stgit@skinsburskii-cloud-desktop.internal.cloudapp.net> Precedence: bulk X-Mailing-List: linux-hyperv@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <177816862362.21765.11809618639989414561.stgit@skinsburskii-cloud-desktop.internal.cloudapp.net> X-ZohoMailClient: External On Thu, May 07, 2026 at 03:43:43PM +0000, Stanislav Kinsburskii wrote: > In mshv_irqfd_assign(), the level-triggered validation for resample > irqfds checks irqfd_lapic_irq.lapic_control.level_triggered before > mshv_irqfd_update() has populated the field. Since the irqfd struct is > zero-allocated, level_triggered is always 0 at that point, causing the > check to always reject resample irqfds with -EINVAL. This makes > level-triggered interrupt resampling — used to avoid interrupt storms > with assigned devices — completely non-functional. What bugs would this manifest as? Why haven't we seen any such bugs so far? Thanks, Anirudh.