Stefan Berger
2007-Sep-07 17:51 UTC
[Xen-devel] Xen linux error message: PCI-DMA: Out of SW-IOMMU space for 65536 bytes at device 0000:02:01.0
One one of my machines running the linux 2.6.18 changes 195, I see a lot of these errrors. Sep 7 13:14:22 test-11 kernel: PCI-DMA: Out of SW-IOMMU space for 65536 bytes at device 0000:02:01.0 Sep 7 13:14:22 test-11 last message repeated 10 times Sep 7 13:14:25 test-11 kernel: PCI-DMA: Out of SW-IOMMU space for 16384 bytes at device 0000:02:01.0 Sep 7 13:14:25 test-11 last message repeated 4 times Sep 7 13:14:25 ttest-11 kernel: PCI-DMA: Out of SW-IOMMU space for 24576 bytes at device 0000:02:01.0 Was this patch http://lists.xensource.com/archives/html/xen-devel/2007-07/msg00418.html supposed to solve this? Stefan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser
2007-Sep-07 18:42 UTC
Re: [Xen-devel] Xen linux error message: PCI-DMA: Out of SW-IOMMU space for 65536 bytes at device 0000:02:01.0
No, you simply don¹t have a big enough swiotlb. The default is 2MB for a machine with less than 2GB of RAM, or 64MB for >2GB systems. You can change to e.g., a 128MB swiotlb by putting swiotlb=128¹ on you dom0 cmdline. -- Keir On 7/9/07 18:51, "Stefan Berger" <stefanb@us.ibm.com> wrote:> > One one of my machines running the linux 2.6.18 changes 195, I see a lot of > these errrors. > > Sep 7 13:14:22 test-11 kernel: PCI-DMA: Out of SW-IOMMU space for 65536 bytes > at device 0000:02:01.0 > Sep 7 13:14:22 test-11 last message repeated 10 times > Sep 7 13:14:25 test-11 kernel: PCI-DMA: Out of SW-IOMMU space for 16384 bytes > at device 0000:02:01.0 > Sep 7 13:14:25 test-11 last message repeated 4 times > Sep 7 13:14:25 ttest-11 kernel: PCI-DMA: Out of SW-IOMMU space for 24576 > bytes at device 0000:02:01.0 > > Was this patch > > http://lists.xensource.com/archives/html/xen-devel/2007-07/msg00418.html > > supposed to solve this? > > Stefan > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Stefan Berger
2007-Sep-07 19:01 UTC
Re: [Xen-devel] Xen linux error message: PCI-DMA: Out of SW-IOMMU space for 65536 bytes at device 0000:02:01.0
xen-devel-bounces@lists.xensource.com wrote on 09/07/2007 02:42:29 PM:> No, you simply don?t have a big enough swiotlb. The default is 2MB > for a machine with less than 2GB of RAM, or 64MB for >2GB systems. > > You can change to e.g., a 128MB swiotlb by putting ?swiotlb=128? on > you dom0 cmdline.Not that I find this a good or intuitive solution, but at least now the error messages have disappeared. Couldn''t this swiotlb grow automatically when needed? Stefan> > -- Keir > > On 7/9/07 18:51, "Stefan Berger" <stefanb@us.ibm.com> wrote:> > One one of my machines running the linux 2.6.18 changes 195, I see a > lot of these errrors. > > Sep 7 13:14:22 test-11 kernel: PCI-DMA: Out of SW-IOMMU space for > 65536 bytes at device 0000:02:01.0 > Sep 7 13:14:22 test-11 last message repeated 10 times > Sep 7 13:14:25 test-11 kernel: PCI-DMA: Out of SW-IOMMU space for > 16384 bytes at device 0000:02:01.0 > Sep 7 13:14:25 test-11 last message repeated 4 times > Sep 7 13:14:25 ttest-11 kernel: PCI-DMA: Out of SW-IOMMU space for > 24576 bytes at device 0000:02:01.0 > > Was this patch > > http://lists.xensource.com/archives/html/xen-devel/2007-07/msg00418.html> > supposed to solve this? > > Stefan > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser
2007-Sep-08 08:57 UTC
Re: [Xen-devel] Xen linux error message: PCI-DMA: Out of SW-IOMMU space for 65536 bytes at device 0000:02:01.0
On 7/9/07 20:01, "Stefan Berger" <stefanb@us.ibm.com> wrote:>> > You can change to e.g., a 128MB swiotlb by putting swiotlb=128¹ on >> > you dom0 cmdline. > > Not that I find this a good or intuitive solution, but at least now the error > messages have disappeared. Couldn''t this swiotlb grow automatically when > needed?No, it is allocated at boot time, and creating a larger one by default would waste memory on most systems. -- Keir _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Muli Ben-Yehuda
2007-Sep-09 05:21 UTC
Re: [Xen-devel] Xen linux error message: PCI-DMA: Out of SW-IOMMU space for 65536 bytes at device 0000:02:01.0
On Sat, Sep 08, 2007 at 09:57:40AM +0100, Keir Fraser wrote:> On 7/9/07 20:01, "Stefan Berger" <stefanb@us.ibm.com> wrote: > > >> > You can change to e.g., a 128MB swiotlb by putting ?swiotlb=128¹ on > >> > you dom0 cmdline. > > > > Not that I find this a good or intuitive solution, but at least now the error > > messages have disappeared. Couldn''t this swiotlb grow automatically when > > needed? > > No, it is allocated at boot time, and creating a larger one by > default would waste memory on most systems.I''ve been toying with the idea of dynamically allocating the swiotlb aperture to handle cases like this, but the added run-time cost and complexity may not be worth it for what is supposed to be a slow-not-really-meant-to-be-used-path. Cheers, Muli _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel