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 mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by smtp.lore.kernel.org (Postfix) with ESMTP id 228F4C433FE for ; Mon, 27 Dec 2021 15:54:03 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 83AE249E08; Mon, 27 Dec 2021 10:54:02 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@kernel.org Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id jnSWTbjgeaMm; Mon, 27 Dec 2021 10:54:01 -0500 (EST) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 6B41F40D23; Mon, 27 Dec 2021 10:54:01 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 88C604024F for ; Mon, 27 Dec 2021 10:54:00 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id NmXPsJESxaaD for ; Mon, 27 Dec 2021 10:53:59 -0500 (EST) Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 678AC40162 for ; Mon, 27 Dec 2021 10:53:59 -0500 (EST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 98A136104C; Mon, 27 Dec 2021 15:53:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0F10BC36AE7; Mon, 27 Dec 2021 15:53:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1640620438; bh=JfRjJBbke0t9wYrDsjzgGQyQfybfI1k8I701E5RWL4o=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=bRW3Glt/AiVN5Cj0LDfujV33Ts6ZRmBt9Zz9Q3HxK/3qs1kXf1/SaqYVrNVeVehqe b17VHwf0LUkVczPE0G8sMirI6G6ySw4L+d9vpGIvP8lFLwTeevSC9+qmmdhoyIijP2 DFxVgzmQoojf7cw5ZUEu//o7BO+K7wU6FrdWvrHInKay+nTjES6XKkXA3NqUwseBQR q++Q3RHmxQ56NJkPMNMSm0c8pZEyKmV4eCSIxUEY6w+CmlZSpT8HKwl/ElcQHi/GrK a0j3FoKJ7gH4VFBUC/zZl1cORVVclEIR4ztPG6tGTlNwrRYLKGZwc8KRntD7zXsAG1 GDErb8QuzeLzw== Received: from cfbb000407.r.cam.camfibre.uk ([185.219.108.64] helo=wait-a-minute.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1n1sJw-00Ea9t-5p; Mon, 27 Dec 2021 15:53:56 +0000 Date: Mon, 27 Dec 2021 15:53:55 +0000 Message-ID: <87pmpiyrfw.wl-maz@kernel.org> From: Marc Zyngier To: eric.auger@redhat.com Subject: Re: [PATCH v2 1/5] hw/arm/virt: Key enablement of highmem PCIe on highmem_ecam In-Reply-To: References: <20211003164605.3116450-1-maz@kernel.org> <20211003164605.3116450-2-maz@kernel.org> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: eric.auger@redhat.com, qemu-devel@nongnu.org, drjones@redhat.com, peter.maydell@linaro.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Cc: kvm@vger.kernel.org, qemu-devel@nongnu.org, kernel-team@android.com, kvmarm@lists.cs.columbia.edu X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu Hi Eric, Picking this up again after a stupidly long time... On Mon, 04 Oct 2021 13:00:21 +0100, Eric Auger wrote: > > Hi Marc, > > On 10/3/21 6:46 PM, Marc Zyngier wrote: > > Currently, the highmem PCIe region is oddly keyed on the highmem > > attribute instead of highmem_ecam. Move the enablement of this PCIe > > region over to highmem_ecam. > > > > Signed-off-by: Marc Zyngier > > --- > > hw/arm/virt-acpi-build.c | 10 ++++------ > > hw/arm/virt.c | 4 ++-- > > 2 files changed, 6 insertions(+), 8 deletions(-) > > > > diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c > > index 037cc1fd82..d7bef0e627 100644 > > --- a/hw/arm/virt-acpi-build.c > > +++ b/hw/arm/virt-acpi-build.c > > @@ -157,10 +157,9 @@ static void acpi_dsdt_add_virtio(Aml *scope, > > } > > > > static void acpi_dsdt_add_pci(Aml *scope, const MemMapEntry *memmap, > > - uint32_t irq, bool use_highmem, bool highmem_ecam, > > - VirtMachineState *vms) > > + uint32_t irq, VirtMachineState *vms) > > { > > - int ecam_id = VIRT_ECAM_ID(highmem_ecam); > > + int ecam_id = VIRT_ECAM_ID(vms->highmem_ecam); > > struct GPEXConfig cfg = { > > .mmio32 = memmap[VIRT_PCIE_MMIO], > > .pio = memmap[VIRT_PCIE_PIO], > > @@ -169,7 +168,7 @@ static void acpi_dsdt_add_pci(Aml *scope, const MemMapEntry *memmap, > > .bus = vms->bus, > > }; > > > > - if (use_highmem) { > > + if (vms->highmem_ecam) { > highmem_ecam is more restrictive than use_highmem: > vms->highmem_ecam &= vms->highmem && (!firmware_loaded || aarch64); > > If I remember correctly there was a problem using highmem ECAM with 32b > AAVMF FW. > > However 5125f9cd2532 ("hw/arm/virt: Add high MMIO PCI region, 512G in > size") introduced high MMIO PCI region without this constraint. Then I really don't understand the point of this highmem_ecam. We only register the highmem version if highmem_ecam is set (see the use of VIRT_ECAM_ID() to pick the right ECAM window). So keying this on highmem makes it expose a device that may not be there the first place since, as you pointed out that highmem_ecam can be false in cases where highmem is true. > So to me we should keep vms->highmem here I really must be missing how this is supposed to work. M. -- Without deviation from the norm, progress is not possible. _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 85955C433FE for ; Mon, 27 Dec 2021 15:55:43 +0000 (UTC) Received: from localhost ([::1]:38624 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1n1sLe-0003KT-8x for qemu-devel@archiver.kernel.org; Mon, 27 Dec 2021 10:55:42 -0500 Received: from eggs.gnu.org ([209.51.188.92]:52110) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n1sK9-0002X8-Pk for qemu-devel@nongnu.org; Mon, 27 Dec 2021 10:54:09 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:50804) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n1sK7-0000g3-Rt for qemu-devel@nongnu.org; Mon, 27 Dec 2021 10:54:09 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 98A136104C; Mon, 27 Dec 2021 15:53:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0F10BC36AE7; Mon, 27 Dec 2021 15:53:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1640620438; bh=JfRjJBbke0t9wYrDsjzgGQyQfybfI1k8I701E5RWL4o=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=bRW3Glt/AiVN5Cj0LDfujV33Ts6ZRmBt9Zz9Q3HxK/3qs1kXf1/SaqYVrNVeVehqe b17VHwf0LUkVczPE0G8sMirI6G6ySw4L+d9vpGIvP8lFLwTeevSC9+qmmdhoyIijP2 DFxVgzmQoojf7cw5ZUEu//o7BO+K7wU6FrdWvrHInKay+nTjES6XKkXA3NqUwseBQR q++Q3RHmxQ56NJkPMNMSm0c8pZEyKmV4eCSIxUEY6w+CmlZSpT8HKwl/ElcQHi/GrK a0j3FoKJ7gH4VFBUC/zZl1cORVVclEIR4ztPG6tGTlNwrRYLKGZwc8KRntD7zXsAG1 GDErb8QuzeLzw== Received: from cfbb000407.r.cam.camfibre.uk ([185.219.108.64] helo=wait-a-minute.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1n1sJw-00Ea9t-5p; Mon, 27 Dec 2021 15:53:56 +0000 Date: Mon, 27 Dec 2021 15:53:55 +0000 Message-ID: <87pmpiyrfw.wl-maz@kernel.org> From: Marc Zyngier To: eric.auger@redhat.com Subject: Re: [PATCH v2 1/5] hw/arm/virt: Key enablement of highmem PCIe on highmem_ecam In-Reply-To: References: <20211003164605.3116450-1-maz@kernel.org> <20211003164605.3116450-2-maz@kernel.org> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: eric.auger@redhat.com, qemu-devel@nongnu.org, drjones@redhat.com, peter.maydell@linaro.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Received-SPF: pass client-ip=139.178.84.217; envelope-from=maz@kernel.org; helo=dfw.source.kernel.org X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.575, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Maydell , Andrew Jones , kvm@vger.kernel.org, qemu-devel@nongnu.org, kernel-team@android.com, kvmarm@lists.cs.columbia.edu Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Hi Eric, Picking this up again after a stupidly long time... On Mon, 04 Oct 2021 13:00:21 +0100, Eric Auger wrote: > > Hi Marc, > > On 10/3/21 6:46 PM, Marc Zyngier wrote: > > Currently, the highmem PCIe region is oddly keyed on the highmem > > attribute instead of highmem_ecam. Move the enablement of this PCIe > > region over to highmem_ecam. > > > > Signed-off-by: Marc Zyngier > > --- > > hw/arm/virt-acpi-build.c | 10 ++++------ > > hw/arm/virt.c | 4 ++-- > > 2 files changed, 6 insertions(+), 8 deletions(-) > > > > diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c > > index 037cc1fd82..d7bef0e627 100644 > > --- a/hw/arm/virt-acpi-build.c > > +++ b/hw/arm/virt-acpi-build.c > > @@ -157,10 +157,9 @@ static void acpi_dsdt_add_virtio(Aml *scope, > > } > > > > static void acpi_dsdt_add_pci(Aml *scope, const MemMapEntry *memmap, > > - uint32_t irq, bool use_highmem, bool highmem_ecam, > > - VirtMachineState *vms) > > + uint32_t irq, VirtMachineState *vms) > > { > > - int ecam_id = VIRT_ECAM_ID(highmem_ecam); > > + int ecam_id = VIRT_ECAM_ID(vms->highmem_ecam); > > struct GPEXConfig cfg = { > > .mmio32 = memmap[VIRT_PCIE_MMIO], > > .pio = memmap[VIRT_PCIE_PIO], > > @@ -169,7 +168,7 @@ static void acpi_dsdt_add_pci(Aml *scope, const MemMapEntry *memmap, > > .bus = vms->bus, > > }; > > > > - if (use_highmem) { > > + if (vms->highmem_ecam) { > highmem_ecam is more restrictive than use_highmem: > vms->highmem_ecam &= vms->highmem && (!firmware_loaded || aarch64); > > If I remember correctly there was a problem using highmem ECAM with 32b > AAVMF FW. > > However 5125f9cd2532 ("hw/arm/virt: Add high MMIO PCI region, 512G in > size") introduced high MMIO PCI region without this constraint. Then I really don't understand the point of this highmem_ecam. We only register the highmem version if highmem_ecam is set (see the use of VIRT_ECAM_ID() to pick the right ECAM window). So keying this on highmem makes it expose a device that may not be there the first place since, as you pointed out that highmem_ecam can be false in cases where highmem is true. > So to me we should keep vms->highmem here I really must be missing how this is supposed to work. M. -- Without deviation from the norm, progress is not possible. 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 477D5C43217 for ; Mon, 27 Dec 2021 15:55:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241135AbhL0Pzp (ORCPT ); Mon, 27 Dec 2021 10:55:45 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:49258 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240838AbhL0Px7 (ORCPT ); Mon, 27 Dec 2021 10:53:59 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A9C4861052 for ; Mon, 27 Dec 2021 15:53:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0F10BC36AE7; Mon, 27 Dec 2021 15:53:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1640620438; bh=JfRjJBbke0t9wYrDsjzgGQyQfybfI1k8I701E5RWL4o=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=bRW3Glt/AiVN5Cj0LDfujV33Ts6ZRmBt9Zz9Q3HxK/3qs1kXf1/SaqYVrNVeVehqe b17VHwf0LUkVczPE0G8sMirI6G6ySw4L+d9vpGIvP8lFLwTeevSC9+qmmdhoyIijP2 DFxVgzmQoojf7cw5ZUEu//o7BO+K7wU6FrdWvrHInKay+nTjES6XKkXA3NqUwseBQR q++Q3RHmxQ56NJkPMNMSm0c8pZEyKmV4eCSIxUEY6w+CmlZSpT8HKwl/ElcQHi/GrK a0j3FoKJ7gH4VFBUC/zZl1cORVVclEIR4ztPG6tGTlNwrRYLKGZwc8KRntD7zXsAG1 GDErb8QuzeLzw== Received: from cfbb000407.r.cam.camfibre.uk ([185.219.108.64] helo=wait-a-minute.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1n1sJw-00Ea9t-5p; Mon, 27 Dec 2021 15:53:56 +0000 Date: Mon, 27 Dec 2021 15:53:55 +0000 Message-ID: <87pmpiyrfw.wl-maz@kernel.org> From: Marc Zyngier To: eric.auger@redhat.com Cc: qemu-devel@nongnu.org, Andrew Jones , Peter Maydell , kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, kernel-team@android.com Subject: Re: [PATCH v2 1/5] hw/arm/virt: Key enablement of highmem PCIe on highmem_ecam In-Reply-To: References: <20211003164605.3116450-1-maz@kernel.org> <20211003164605.3116450-2-maz@kernel.org> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: eric.auger@redhat.com, qemu-devel@nongnu.org, drjones@redhat.com, peter.maydell@linaro.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi Eric, Picking this up again after a stupidly long time... On Mon, 04 Oct 2021 13:00:21 +0100, Eric Auger wrote: > > Hi Marc, > > On 10/3/21 6:46 PM, Marc Zyngier wrote: > > Currently, the highmem PCIe region is oddly keyed on the highmem > > attribute instead of highmem_ecam. Move the enablement of this PCIe > > region over to highmem_ecam. > > > > Signed-off-by: Marc Zyngier > > --- > > hw/arm/virt-acpi-build.c | 10 ++++------ > > hw/arm/virt.c | 4 ++-- > > 2 files changed, 6 insertions(+), 8 deletions(-) > > > > diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c > > index 037cc1fd82..d7bef0e627 100644 > > --- a/hw/arm/virt-acpi-build.c > > +++ b/hw/arm/virt-acpi-build.c > > @@ -157,10 +157,9 @@ static void acpi_dsdt_add_virtio(Aml *scope, > > } > > > > static void acpi_dsdt_add_pci(Aml *scope, const MemMapEntry *memmap, > > - uint32_t irq, bool use_highmem, bool highmem_ecam, > > - VirtMachineState *vms) > > + uint32_t irq, VirtMachineState *vms) > > { > > - int ecam_id = VIRT_ECAM_ID(highmem_ecam); > > + int ecam_id = VIRT_ECAM_ID(vms->highmem_ecam); > > struct GPEXConfig cfg = { > > .mmio32 = memmap[VIRT_PCIE_MMIO], > > .pio = memmap[VIRT_PCIE_PIO], > > @@ -169,7 +168,7 @@ static void acpi_dsdt_add_pci(Aml *scope, const MemMapEntry *memmap, > > .bus = vms->bus, > > }; > > > > - if (use_highmem) { > > + if (vms->highmem_ecam) { > highmem_ecam is more restrictive than use_highmem: > vms->highmem_ecam &= vms->highmem && (!firmware_loaded || aarch64); > > If I remember correctly there was a problem using highmem ECAM with 32b > AAVMF FW. > > However 5125f9cd2532 ("hw/arm/virt: Add high MMIO PCI region, 512G in > size") introduced high MMIO PCI region without this constraint. Then I really don't understand the point of this highmem_ecam. We only register the highmem version if highmem_ecam is set (see the use of VIRT_ECAM_ID() to pick the right ECAM window). So keying this on highmem makes it expose a device that may not be there the first place since, as you pointed out that highmem_ecam can be false in cases where highmem is true. > So to me we should keep vms->highmem here I really must be missing how this is supposed to work. M. -- Without deviation from the norm, progress is not possible.