From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 6C1AC271805; Wed, 12 Feb 2025 02:17:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739326651; cv=none; b=qKRJSS/81+4gBdFXWRk8aTIw3ZH7HHFzOHUGRN473I59RluNr54u6UCjwe1AOJTsRpBjhSRWqBScqzk+8Fu3q9c6Er9D5/8GPcooa0HfjLkjNvAqt7LnYGBT8Zc0MYW94Dud5lMSSeRAXxHIiId/tebhHDmDcmUxGeun6wcgA+w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739326651; c=relaxed/simple; bh=IfNzFSoFebDHVFD6C3un0hfHjr9AseBn27h5i77Vq+4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Pp/kVGDPY1AuAR0Ln9/hWzO/+83xKbJZlvVn2KHGJyp/czzw6Jq18znjh8zdn5ylcAgAEHujDrB91x0F7Ir1K3LjMkSA5BXhsjMAw51sDcpuCYl177R51NlVhH7y+f/+LH4Kxjz5D0K5kVR+oaJuvJ0NFN6FVekkzdB421MX1fs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gKeV1YZ0; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gKeV1YZ0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 86D68C4CEDD; Wed, 12 Feb 2025 02:17:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1739326650; bh=IfNzFSoFebDHVFD6C3un0hfHjr9AseBn27h5i77Vq+4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gKeV1YZ0Ve18A8Hic9PwaGOUW1qk6t7uDfTSjB62RfdLSvh0qBLZxHSJhB8h451l5 L+yVT0YG4EQTBjNfJqAj6U+K2OswjMnSDo6nXInbmLdvWIxEh9Jhbd72aHwpNpzU2i J96wlYe5lZUVyg2Vghq+EbHtjLI0r0mzG/QyE8SJLgF6IjykkaX1VqEnyeaPDmfc+V SrPVSI4F4lq0xA/XPFZae/tvBskaHyy3YJMNRErnmfJT5o/+GeRQ0U5ysS74pBlMvG qmGuuJZvKPNQ/b4R5L9q8wAkJRQATfh4DGz7kU1Geuj6tPikcodhsUekLimUVxB5IT wc4MRIx4h+baA== Date: Wed, 12 Feb 2025 02:17:29 +0000 From: Wei Liu To: Roman Kisel Cc: namjain@linux.microsoft.com, bp@alien8.de, dave.hansen@linux.intel.com, decui@microsoft.com, haiyangz@microsoft.com, kys@microsoft.com, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, mingo@redhat.com, ssengar@linux.microsoft.com, tglx@linutronix.de, wei.liu@kernel.org, x86@kernel.org Subject: Re: [PATCH] x86/hyperv/vtl: Stop kernel from probing VTL0 low memory Message-ID: References: <20250116061224.1701-1-namjain@linux.microsoft.com> <20250117170141.1351283-1-romank@linux.microsoft.com> 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=us-ascii Content-Disposition: inline In-Reply-To: <20250117170141.1351283-1-romank@linux.microsoft.com> On Fri, Jan 17, 2025 at 09:01:41AM -0800, Roman Kisel wrote: > > For Linux, running in Hyper-V VTL (Virtual Trust Level), kernel in VTL2 > > tries to access VTL0 low memory in probe_roms. This memory is not > > described in the e820 map. Initialize probe_roms call to no-ops > > during boot for VTL2 kernel to avoid this. The issue got identified > > in OpenVMM which detects invalid accesses initiated from kernel running > > in VTL2. > > > > Co-developed-by: Saurabh Sengar > > Signed-off-by: Saurabh Sengar > > Signed-off-by: Naman Jain > > --- > > arch/x86/hyperv/hv_vtl.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/arch/x86/hyperv/hv_vtl.c b/arch/x86/hyperv/hv_vtl.c > > index 4e1b1e3b5658..3f4e20d7b724 100644 > > --- a/arch/x86/hyperv/hv_vtl.c > > +++ b/arch/x86/hyperv/hv_vtl.c > > @@ -30,6 +30,7 @@ void __init hv_vtl_init_platform(void) > > x86_platform.realmode_init = x86_init_noop; > > x86_init.irqs.pre_vector_init = x86_init_noop; > > x86_init.timers.timer_init = x86_init_noop; > > + x86_init.resources.probe_roms = x86_init_noop; > > > > /* Avoid searching for BIOS MP tables */ > > x86_init.mpparse.find_mptable = x86_init_noop; > > > > base-commit: 37136bf5c3a6f6b686d74f41837a6406bec6b7bc > > -- > > 2.43.0 > > Thanks, Naman! > > Tested-by: Roman Kisel > Reviewed-by: Roman Kisel Applied to hyperv-fixes. Thanks.