[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: [PATCH] xen: introduce xen_vring_use_dma
- To: Stefano Stabellini <sstabellini@xxxxxxxxxx>
- From: Peng Fan <peng.fan@xxxxxxx>
- Date: Tue, 30 Jun 2020 01:40:04 +0000
- Accept-language: en-US
- Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nxp.com; dmarc=pass action=none header.from=nxp.com; dkim=pass header.d=nxp.com; arc=none
- Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=Os/L3ofogs4QnE3I4j6ChyfYRUtY/PkOePGOECaI4Rw=; b=XS0p9SIQbUw2hbz3kgfL9boi2YDEnv4ZfgFcS19SDOU+JTI063UY7mYWCOQ/FAcLo8BYBspe5l3UIDapVXdmjL3V1gxynbJoYaHjxpT4HPExuBh93QVsfsE8bwdc2VoNsEGLzQOsC7h0WcEjPtFqzU33ciheDrRfOX76BjEH01uHMvzkXwBBsvuc217oIF7KdlAKQh32TmpnGxykvPo9BkbHEDZtmpSK0fCSZsNRAEtouSjrM5mqjPuPCjeGpg3GlhblLkQLuAhhGtdRP9w+HNto3NRcVmx2riYUW7geRqfzP36F5qrxjOuiW6iyJa0rsHk6rJqVonGgP4q8KFjz0Q==
- Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=lwdYoXgJsqF/Ba6f9pApxpysKoUGdA2aLQE10N31TJ6BUeJLPvHuwOeW7KUYM61WLVknYhH/LXLDFaIkem4FsW30dBiw48r0n5Y08mhgKazIGmUIvepqFQ8q+prHd6cvWf5YpKmIZ/6dY5ckrdkDG+Cb9x3knOnWo62GMscpCpBvyCqmlq72UZE9lGgPRYO9vLvQpt6n6ZBRcvsWw/2PABBkN6uiOgCxK+yOD6XEeu2zf/hUqD12BcIBRlZ6MHN0psOWifZ0MYHWJZTVIAYfqnKQxtv38Tt18LQWQU7j5kF4pZydRkoxYiQG68D6Wct3Uc1Af/IwT6zkWby26Odf9g==
- Authentication-results: kernel.org; dkim=none (message not signed) header.d=none;kernel.org; dmarc=none action=none header.from=nxp.com;
- Cc: "jgross@xxxxxxxx" <jgross@xxxxxxxx>, "konrad.wilk@xxxxxxxxxx" <konrad.wilk@xxxxxxxxxx>, "jasowang@xxxxxxxxxx" <jasowang@xxxxxxxxxx>, "x86@xxxxxxxxxx" <x86@xxxxxxxxxx>, "linux-kernel@xxxxxxxxxxxxxxx" <linux-kernel@xxxxxxxxxxxxxxx>, "virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx" <virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx>, "iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx" <iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx>, "Michael S. Tsirkin" <mst@xxxxxxxxxx>, dl-linux-imx <linux-imx@xxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxxx>, "boris.ostrovsky@xxxxxxxxxx" <boris.ostrovsky@xxxxxxxxxx>, "linux-arm-kernel@xxxxxxxxxxxxxxxxxxx" <linux-arm-kernel@xxxxxxxxxxxxxxxxxxx>
- Delivery-date: Tue, 30 Jun 2020 01:40:33 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
- Thread-index: AQHWSgTusARd8c8cRkWwDit233DtZajneYoAgACU6oCAAC7QAIAAEpoAgAAGSwCAAUK2gIABcSaAgAPk6cCAAVzJgIAAHp3A
- Thread-topic: [PATCH] xen: introduce xen_vring_use_dma
> Subject: RE: [PATCH] xen: introduce xen_vring_use_dma
>
> On Mon, 29 Jun 2020, Peng Fan wrote:
> > > > If that is the case, how is it possible that virtio breaks on ARM
> > > > using the default dma_ops? The breakage is not Xen related (except
> > > > that Xen turns dma_ops on). The original message from Peng was:
> > > >
> > > > vring_map_one_sg -> vring_use_dma_api
> > > > -> dma_map_page
> > > > -> __swiotlb_map_page
> > > > ->swiotlb_map_page
> > > >
> > > > ->__dma_map_area(phys_to_virt(dma_to_phys(dev,
> > > dev_addr)), size, dir);
> > > > However we are using per device dma area for rpmsg, phys_to_virt
> > > > could not return a correct virtual address for virtual address in
> > > > vmalloc area. Then kernel panic.
> > > >
> > > > I must be missing something. Maybe it is because it has to do with
> RPMesg?
> > >
> > > I think it's an RPMesg bug, yes
> >
> > rpmsg bug is another issue, it should not use dma_alloc_coherent for
> > reserved area, and use vmalloc_to_page.
> >
> > Anyway here using dma api will also trigger issue.
>
> Is the stack trace above for the RPMesg issue or for the Trusty issue?
The stack trace you pasted is rpmsg issue.
> If it is the stack trace for RPMesg, can you also post the Trusty stack
> trace? Or
> are they indentical?
There is no stack dump here. It successfully using swiotlb to do a map,
but we actually no need swiotlb in domu to do the map.
Thanks,
Peng.
|
