From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 407DB1400C; Mon, 2 Feb 2026 16:56:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770051378; cv=none; b=dOraOS1BFvZl5/0/t5Dfneeirsx4q2zsKkqBgCdO51kajJxFG73HxNwsU3W1mU3w5SL9ePefN5HI1SWu+N0by392yvJBZxNCMjGTrzHB7kHEcaaJ4xK8yaRorIHElkiFylvpBkty3h1laIzZvaBTfVHZCGe//aHu7f/3tsblAeI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770051378; c=relaxed/simple; bh=YHzu/3DnCsZpFhSOf4RIi1l/kwpWFH5GlblRo6zpXN4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=QIQTrWAxyWjvhfKmJvZpDDnhQwOHrG+uA598Fx50TjvZH7Drm+zmueQeeYx8Qv/LckW4mq+l6BKzOcV7/kKMAk5TOVFq4ZQiXbTziJaXHX6vW5oB+lhNOUA+EjL0KwqoP4hZ3SCV5IBqRMDcYWujgTS4DuULiL4AMPsclR/cXu4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=Kz5lkvHo; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="Kz5lkvHo" Received: from [192.168.0.105] (unknown [49.205.250.63]) by linux.microsoft.com (Postfix) with ESMTPSA id E30AB20B7168; Mon, 2 Feb 2026 08:56:14 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com E30AB20B7168 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1770051377; bh=DeZSj6Zj/3RidThgBmwdnPrrjVo2bvT3MWr1TnZnhTM=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=Kz5lkvHoZ1DsxYPp2MVHtI6Gq4u6bu3vKWuUSMw/6bxd2eRfXSo3xR38Vd0orxO38 RaVxeNUbdkGLl4mKPUqdl4uWT50mV4JdQ3WXwx6x3EedyY5rx6kUo38JIv6wSycZEw PfXYroPLmqs9+EPW7l62q11LygRKp6vvkz6apqIc= Message-ID: <26bdf7a9-91ea-4236-a5a6-d7f8571ab87b@linux.microsoft.com> Date: Mon, 2 Feb 2026 22:26:10 +0530 Precedence: bulk X-Mailing-List: linux-hyperv@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] mshv: Make MSHV mutually exclusive with KEXEC To: Stanislav Kinsburskii , kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com Cc: linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org References: <176920684805.250171.6817228088359793537.stgit@skinsburskii-cloud-desktop.internal.cloudapp.net> Content-Language: en-US From: Naman Jain In-Reply-To: <176920684805.250171.6817228088359793537.stgit@skinsburskii-cloud-desktop.internal.cloudapp.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 1/24/2026 3:50 AM, Stanislav Kinsburskii wrote: > The MSHV driver deposits kernel-allocated pages to the hypervisor during > runtime and never withdraws them. This creates a fundamental incompatibility > with KEXEC, as these deposited pages remain unavailable to the new kernel > loaded via KEXEC, leading to potential system crashes upon kernel accessing > hypervisor deposited pages. > > Make MSHV mutually exclusive with KEXEC until proper page lifecycle > management is implemented. > I have not gone through entire conversation that has happened already on this, but if you send a next version for this, please change commit msg and subject to include MSHV_ROOT instead of MSHV, to avoid confusion. Regards, Naman > Signed-off-by: Stanislav Kinsburskii > --- > drivers/hv/Kconfig | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/hv/Kconfig b/drivers/hv/Kconfig > index 7937ac0cbd0f..cfd4501db0fa 100644 > --- a/drivers/hv/Kconfig > +++ b/drivers/hv/Kconfig > @@ -74,6 +74,7 @@ config MSHV_ROOT > # e.g. When withdrawing memory, the hypervisor gives back 4k pages in > # no particular order, making it impossible to reassemble larger pages > depends on PAGE_SIZE_4KB > + depends on !KEXEC > select EVENTFD > select VIRT_XFER_TO_GUEST_WORK > select HMM_MIRROR > >