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Message-ID: <aea0fbb0d44748bb4419495d6d95485e585f65f0.camel@linux.ibm.com>
Subject: Re: [PATCH 1/1] s390/virtio_ccw: fix config change notifications
From: Eric Farman <farman@linux.ibm.com>
To: Halil Pasic <pasic@linux.ibm.com>, Cornelia Huck <cohuck@redhat.com>,
        Heiko Carstens <hca@linux.ibm.com>, Vasily Gorbik <gor@linux.ibm.com>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
        Christian Borntraeger
 <borntraeger@linux.ibm.com>,
        Sven Schnelle <svens@linux.ibm.com>, linux-s390@vger.kernel.org,
        virtualization@lists.linux.dev, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc: Boqiao Fu <bfu@redhat.com>, Sebastian Mitterle <smitterl@redhat.com>
Date: Thu, 13 Jun 2024 10:43:07 -0400
In-Reply-To: <20240611214716.1002781-1-pasic@linux.ibm.com>
References: <20240611214716.1002781-1-pasic@linux.ibm.com>
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On Tue, 2024-06-11 at 23:47 +0200, Halil Pasic wrote:
> Commit e3e9bda38e6d ("s390/virtio_ccw: use DMA handle from DMA API")
> broke configuration change notifications for virtio-ccw by putting
> the
> DMA address of *indicatorp directly into ccw->cda disregarding the
> fact
> that if !!(vcdev->is_thinint) then the function
> virtio_ccw_register_adapter_ind() will overwrite that ccw->cda value
> with the address of the virtio_thinint_area so it can actually set up
> the adapter interrupts via CCW_CMD_SET_IND_ADAPTER.=C2=A0 Thus we end up
> pointing to the wrong object for both CCW_CMD_SET_IND if setting up
> the
> adapter interrupts fails, and for CCW_CMD_SET_CONF_IND regardless
> whether it succeeds or fails.
>=20
> To fix this, let us save away the dma address of *indicatorp in a
> local
> variable, and copy it to ccw->cda after the "vcdev->is_thinint"
> branch.
>=20
> Reported-by: Boqiao Fu <bfu@redhat.com>
> Reported-by: Sebastian Mitterle <smitterl@redhat.com>
> Fixes: e3e9bda38e6d ("s390/virtio_ccw: use DMA handle from DMA API")
> Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
> ---
> I know that checkpatch.pl complains about a missing 'Closes' tag.
> Unfortunately I don't have an appropriate URL at hand. @Sebastian,
> @Boqiao: do you have any suggetions?
> ---
> =C2=A0drivers/s390/virtio/virtio_ccw.c | 4 +++-
> =C2=A01 file changed, 3 insertions(+), 1 deletion(-)

Reviewed-by: Eric Farman <farman@linux.ibm.com>