From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4C421C71136 for ; Mon, 16 Jun 2025 20:08:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=RWf4U2IMgfXaKMSLGJUCrHvubnG0tLPF0JXW2PD8mi0=; b=FjB5pUeJpL/7mYN2CxLHmI7Hv7 5nCz+16HUynhkn2MJ6ca3j3tjll3tiMbtfxQAU+Juw12MhBozbPCqc+jC0qfkam2FAW4/G6w8szUV 8cvvLQtoQHfbCc1E6R8xQzqQZ6Am2ksg7A59MqMgvVUoxz/rJgBxf9CbYRbGeqcwaUuDNN8ssQoMh 0xVd3a5XGdcn4u5tUnRM+bgBTlIIyAKrm6iiEE6t1How5TXh71F+qVQFAPF1Gr0aculpA5Nx93grG g9ucl/Jwjp+EUx/BMh0pZePAUN4/9jtHcxJl4MLNjWSAsOf0swK9wmBboqjkTk4TeZKEg3OJmzIk9 2tU2MHmg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uRG8H-00000005R8r-0jY9; Mon, 16 Jun 2025 20:08:41 +0000 Received: from linux.microsoft.com ([13.77.154.182]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uRG63-00000005QyL-1EV2 for linux-arm-kernel@lists.infradead.org; Mon, 16 Jun 2025 20:06:24 +0000 Received: from [100.65.1.24] (unknown [20.236.11.42]) by linux.microsoft.com (Postfix) with ESMTPSA id A030C21176C6; Mon, 16 Jun 2025 13:06:20 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com A030C21176C6 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1750104381; bh=RWf4U2IMgfXaKMSLGJUCrHvubnG0tLPF0JXW2PD8mi0=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=MwygWuhajk7TGYV1hsriMnPH/Z615YS+VR6NW/7XY+ka4XNr/WLH2QUZibl6KRgys duta2oQez2pfYwZQIs/JdGdS7BHRSYlkI3IaA2ECLv+a5lZnTkfKCJiuOuMTv1PfU1 VHKF/NIqb+R7AbxYyEWJNa2pTcbblAVqovZtzrig= Message-ID: <38127f1a-3761-48c7-8e95-1f677d6bd7b3@linux.microsoft.com> Date: Mon, 16 Jun 2025 13:06:20 -0700 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/4] PCI: hv: Do not do vmbus initialization on baremetal To: Michael Kelley , "linux-hyperv@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "linux-pci@vger.kernel.org" Cc: "kys@microsoft.com" , "haiyangz@microsoft.com" , "wei.liu@kernel.org" , "decui@microsoft.com" , "catalin.marinas@arm.com" , "will@kernel.org" , "tglx@linutronix.de" , "mingo@redhat.com" , "bp@alien8.de" , "dave.hansen@linux.intel.com" , "hpa@zytor.com" , "lpieralisi@kernel.org" , "kw@linux.com" , "manivannan.sadhasivam@linaro.org" , "robh@kernel.org" , "bhelgaas@google.com" , "jinankjain@linux.microsoft.com" , "skinsburskii@linux.microsoft.com" , "mrathor@linux.microsoft.com" , "x86@kernel.org" References: <1749599526-19963-1-git-send-email-nunodasneves@linux.microsoft.com> <1749599526-19963-2-git-send-email-nunodasneves@linux.microsoft.com> Content-Language: en-US From: Nuno Das Neves In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250616_130623_389422_4E5E5313 X-CRM114-Status: GOOD ( 17.35 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 6/11/2025 4:06 PM, Michael Kelley wrote: > From: Nuno Das Neves Sent: Tuesday, June 10, 2025 4:52 PM >> >> From: Mukesh Rathor > > The patch Subject line is confusing to me. Perhaps this better captures > the intent: > > "PCI: hv: Don't load the driver for the root partition on a bare-metal hypervisor" > Thanks, that does make more sense. >> >> init_hv_pci_drv() is not relevant for root partition on baremetal as there >> is no vmbus. On nested (with a Windows L1 root), vmbus is present. > > This needs more precision. init_hv_pci_drv() isn't what is > "not relevant". It's the entire driver that doesn't need to be loaded > because the root partition on a bare-metal hypervisor doesn't use > VMBus. It's only when the root partition is running on a nested > hypervisor that it uses VMBus, and hence may need the Hyper-V > PCI driver to be loaded. > I'll update it so it is clearer, thanks. >> >> Signed-off-by: Mukesh Rathor >> Signed-off-by: Nuno Das Neves >> --- >> drivers/pci/controller/pci-hyperv.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c >> index b4f29ee75848..4d25754dfe2f 100644 >> --- a/drivers/pci/controller/pci-hyperv.c >> +++ b/drivers/pci/controller/pci-hyperv.c >> @@ -4150,6 +4150,9 @@ static int __init init_hv_pci_drv(void) >> if (!hv_is_hyperv_initialized()) >> return -ENODEV; >> >> + if (hv_root_partition() && !hv_nested) >> + return -ENODEV; >> + >> ret = hv_pci_irqchip_init(); >> if (ret) >> return ret; >> -- >> 2.34.1