From: Paul Mackerras <paulus@ozlabs.org>
Date: Fri, 31 May 2019 06:36:52 +0000
Subject: Re: [PATCH] KVM: PPC: Book3S HV: XIVE: fix page offset when clearing ESB pages
Message-Id: <20190531063652.GF26651@blackberry>
List-Id: <kvm-ppc.vger.kernel.org>
References: <20190528211324.18656-1-clg@kaod.org>
In-Reply-To: <20190528211324.18656-1-clg@kaod.org>
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To: =?iso-8859-1?Q?C=E9dric?= Le Goater <clg@kaod.org>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>, David Gibson <david@gibson.dropbear.id.au>, Greg Kurz <groug@kaod.org>, kvm@vger.kernel.org, kvm-ppc@vger.kernel.org

On Tue, May 28, 2019 at 11:13:24PM +0200, C=E9dric Le Goater wrote:
> Under XIVE, the ESB pages of an interrupt are used for interrupt
> management (EOI) and triggering. They are made available to guests
> through a mapping of the XIVE KVM device.
>=20
> When a device is passed-through, the passthru_irq helpers,
> kvmppc_xive_set_mapped() and kvmppc_xive_clr_mapped(), clear the ESB
> pages of the guest IRQ number being mapped and let the VM fault
> handler repopulate with the correct page.
>=20
> The ESB pages are mapped at offset 4 (KVM_XIVE_ESB_PAGE_OFFSET) in the
> KVM device mapping. Unfortunately, this offset was not taken into
> account when clearing the pages. This lead to issues with the
> passthrough devices for which the interrupts were not functional under
> some guest configuration (tg3 and single CPU) or in any configuration
> (e1000e adapter).
>=20
> Signed-off-by: C=E9dric Le Goater <clg@kaod.org>

Thanks, patch applied to my kvm-ppc-fixes branch.

Paul.