From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoffer Dall Subject: Re: ARM: PCI devices emulation broken with KVM due to cache issue Date: Fri, 17 Apr 2015 16:06:48 +0200 Message-ID: <20150417140648.GJ6186@cbox> References: <552FDD13.4090006@redhat.com> <20150417092910.GI6186@cbox> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 609494CCD3 for ; Fri, 17 Apr 2015 09:58:41 -0400 (EDT) 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 gBYAIStglK2P for ; Fri, 17 Apr 2015 09:58:40 -0400 (EDT) Received: from mail-lb0-f181.google.com (mail-lb0-f181.google.com [209.85.217.181]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id D041B4CBD2 for ; Fri, 17 Apr 2015 09:58:39 -0400 (EDT) Received: by lbbzk7 with SMTP id zk7so83877268lbb.0 for ; Fri, 17 Apr 2015 07:06:36 -0700 (PDT) Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: =?iso-8859-1?B?Suly6W15IEZhbmd16GRl?= Cc: Paolo Bonzini , VirtualOpenSystems Technical Team , QEMU Developers , kvmarm@lists.cs.columbia.edu List-Id: kvmarm@lists.cs.columbia.edu T24gRnJpLCBBcHIgMTcsIDIwMTUgYXQgMDM6NDg6MzVQTSArMDIwMCwgSsOpcsOpbXkgRmFuZ3XD qGRlIHdyb3RlOgo+IE9uIEZyaSwgQXByIDE3LCAyMDE1IGF0IDExOjI5IEFNLCBDaHJpc3RvZmZl ciBEYWxsCj4gPGNocmlzdG9mZmVyLmRhbGxAbGluYXJvLm9yZz4gd3JvdGU6Cj4gPiBPbiBUaHUs IEFwciAxNiwgMjAxNSBhdCAwNjowMjoyN1BNICswMjAwLCBQYW9sbyBCb256aW5pIHdyb3RlOgo+ ID4+Cj4gPj4KPiA+PiBPbiAxNi8wNC8yMDE1IDE3OjU0LCBKw6lyw6lteSBGYW5ndcSNZGUgd3Jv dGU6Cj4gPj4gPiBUaGUgZ3Vlc3Qga2VybmVsIGRyaXZlciBvZiB0aGUgbHNpIGRldmljZSBmYWls cyB0byBlbmFibGUgaXQgY29ycmVjdGx5Cj4gPj4gPiB3aXRoIGEgY2FjaGUgZXJyb3I6Cj4gPj4g PiBbLi4uXQo+ID4+ID4gc3ltNTNjOHh4IDAwMDA6MDA6MDEuMDogZW5hYmxpbmcgZGV2aWNlICgw MTAwIC0+IDAxMDMpCj4gPj4gPiBzeW0wOiA8ODk1YT4gcmV2IDB4MCBhdCBwY2kgMDAwMDowMDow MS4wIGlycSA1NAo+ID4+ID4gc3ltMDogTm8gTlZSQU0sIElEIDcsIEZhc3QtNDAsIExWRCwgcGFy aXR5IGNoZWNraW5nCj4gPj4gPiBDQUNIRSBURVNUIEZBSUxFRDogY2hpcCB3cm90ZSAyLCBob3N0 IHJlYWQgMS4KPiA+PiA+IHN5bTA6IENBQ0hFIElOQ09SUkVDVExZIENPTkZJR1VSRUQuCj4gPj4g PiBzeW0wOiBnaXZpbmcgdXAgLi4uCj4gPj4gPiBbLi4uXQo+ID4+Cj4gPj4gTm90ZSB0aGF0IHRo aXMgaXMganVzdCBhIGZhaWx1cmUgaW4gdGhlIGRyaXZlciBzZWxmLXRlc3QuICBJdCBoYXMKPiA+ PiBub3RoaW5nIHRvIGRvIHdpdGggdGhlIHByb2Nlc3NvciBjYWNoZSAodGhvdWdoIHRoZXJlIGFy ZSBvdGhlciBwcm9ibGVtcwo+ID4+IHdpdGggUENJIGFuZCB0aGUgcHJvY2Vzc29yIGNhY2hlIGlu IEtWTSBtb2RlKS4KPiA+Pgo+ID4+IERvIG5vdCB1c2UgdGhpcyBRRU1VIGRldmljZS4gIFRoZSBl bXVsYXRpb24gaXMgaW5jb21wbGV0ZSBhbmQgaXQncyBzbG93Lgo+ID4+ICBVc2UgdmlydGlvLXNj c2kgb3IgbWVnYXNhcyBpbnN0ZWFkLiAgU3RpbGwsIEknbSBub3Qgc3VyZSB0aGF0IHdvdWxkCj4g Pj4gd29yayB3aXRoIEtWTTsgYXMgZmFyIGFzIEkga25vdywgbW9zdCB3b3JrIG9uIHRoZSBBUk0g UENJIGhvc3QgYnJpZGdlCj4gPj4gd2FzIGRvbmUgdXNpbmcgVUVGSSBmaXJtd2FyZS4KPiA+Pgo+ ID4gSSd2ZSBiZWVuIHJ1bm5pbmcgYSBudW1iZXIgb2YgdGVzdHMgbGF0ZWx5IHVzaW5nIHZpcnRp by1uZXQtcGNpIGFuZAo+ID4gdmlydGlvLWJsay1wY2kgb24gWEdlbmUgYXQgaXQgd29ya3MgbGlr ZSBhIGNoYXJtLgo+IAo+IEl0IHNob3VsZCBiZSBub3RlZCB0aGF0IGFsbCB0aGVzZSBkZXZpY2Vz IHdvcmsgZmluZSBvbiB4ODYgd2l0aCBLVk0KPiBlbmFibGVkLgo+IAo+IE9mIGNvdXJzZSwgbm90 IGFsbCBQQ0kgZGV2aWNlcyBhcmUgYWZmZWN0ZWQsIGUuZy4gdmlydGlvLSogZGV2aWNlcwo+IHdv cmsgZmluZSBmb3IgbWUgYWxzby4gSG93ZXZlciwgc2hvdWxkIHRoaXMgZmFpbHVyZSBiZSBjb25z aWRlcmVkCj4gbm9ybWFsIHdpdGggS1ZNIG9uIEFSTSwgd2hpbGUgaXQgd29ya3Mgb24geDg2Pwo+ IAo+IEZvciBpbnN0YW5jZSwgbGV0J3MgdGFrZSB0aGUgdXNlIGNhc2Ugd2hlcmUgdGhlcmUgaXMg bm8gdmlydGlvCj4gYWx0ZXJuYXRpdmU6IFVTQiBkZXZpY2VzIChwYXNzdGhyb3VnaCBvciBlbXVs YXRlZCkgYXR0YWNoZWQgdG8gYSBQQ0kKPiBVU0IgY29udHJvbGxlciwgaG93IGlzIHRoaXMgc3Vw cG9zZWQgdG8gd29yayB3aXRoIEtWTSBvbiBBUk0/Cj4gVGhlIG9ubHkgd2F5IHRvIG1ha2UgdXNi LWVoY2kgd29ya2luZyB0aGF0IEkgYW0gYXdhcmUsIGlzCj4gd2l0aCB0aGlzIGNhY2hlIGhhY2su CgpBcyBQYW9sbyBzYWlkLCB3ZSBrbm93IHRoZXJlIGFyZSBjYWNoZSBpc3N1ZXMgb24gS1ZNL0FS TSBhbmQgd2UgYXJlCndvcmtpbmcgdGhyb3VnaC4gIFBhdGNoZXMgYXJlIGFzIGFsd2F5cyB3ZWxj b21lIDspCgotQ2hyaXN0b2ZmZXIKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX18Ka3ZtYXJtIG1haWxpbmcgbGlzdAprdm1hcm1AbGlzdHMuY3MuY29sdW1iaWEu ZWR1Cmh0dHBzOi8vbGlzdHMuY3MuY29sdW1iaWEuZWR1L21haWxtYW4vbGlzdGluZm8va3ZtYXJt Cg== From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54685) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yj6up-00078O-Cf for qemu-devel@nongnu.org; Fri, 17 Apr 2015 10:06:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Yj6uj-0004F4-Qq for qemu-devel@nongnu.org; Fri, 17 Apr 2015 10:06:43 -0400 Received: from mail-la0-f47.google.com ([209.85.215.47]:33509) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yj6uj-0004Ea-Hy for qemu-devel@nongnu.org; Fri, 17 Apr 2015 10:06:37 -0400 Received: by layy10 with SMTP id y10so81145885lay.0 for ; Fri, 17 Apr 2015 07:06:36 -0700 (PDT) Date: Fri, 17 Apr 2015 16:06:48 +0200 From: Christoffer Dall Message-ID: <20150417140648.GJ6186@cbox> References: <552FDD13.4090006@redhat.com> <20150417092910.GI6186@cbox> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Subject: Re: [Qemu-devel] ARM: PCI devices emulation broken with KVM due to cache issue List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?iso-8859-1?B?Suly6W15IEZhbmd16GRl?= Cc: Paolo Bonzini , VirtualOpenSystems Technical Team , QEMU Developers , kvmarm@lists.cs.columbia.edu On Fri, Apr 17, 2015 at 03:48:35PM +0200, Jérémy Fanguède wrote: > On Fri, Apr 17, 2015 at 11:29 AM, Christoffer Dall > wrote: > > On Thu, Apr 16, 2015 at 06:02:27PM +0200, Paolo Bonzini wrote: > >> > >> > >> On 16/04/2015 17:54, Jérémy Fangučde wrote: > >> > The guest kernel driver of the lsi device fails to enable it correctly > >> > with a cache error: > >> > [...] > >> > sym53c8xx 0000:00:01.0: enabling device (0100 -> 0103) > >> > sym0: <895a> rev 0x0 at pci 0000:00:01.0 irq 54 > >> > sym0: No NVRAM, ID 7, Fast-40, LVD, parity checking > >> > CACHE TEST FAILED: chip wrote 2, host read 1. > >> > sym0: CACHE INCORRECTLY CONFIGURED. > >> > sym0: giving up ... > >> > [...] > >> > >> Note that this is just a failure in the driver self-test. It has > >> nothing to do with the processor cache (though there are other problems > >> with PCI and the processor cache in KVM mode). > >> > >> Do not use this QEMU device. The emulation is incomplete and it's slow. > >> Use virtio-scsi or megasas instead. Still, I'm not sure that would > >> work with KVM; as far as I know, most work on the ARM PCI host bridge > >> was done using UEFI firmware. > >> > > I've been running a number of tests lately using virtio-net-pci and > > virtio-blk-pci on XGene at it works like a charm. > > It should be noted that all these devices work fine on x86 with KVM > enabled. > > Of course, not all PCI devices are affected, e.g. virtio-* devices > work fine for me also. However, should this failure be considered > normal with KVM on ARM, while it works on x86? > > For instance, let's take the use case where there is no virtio > alternative: USB devices (passthrough or emulated) attached to a PCI > USB controller, how is this supposed to work with KVM on ARM? > The only way to make usb-ehci working that I am aware, is > with this cache hack. As Paolo said, we know there are cache issues on KVM/ARM and we are working through. Patches are as always welcome ;) -Christoffer