Xen project Mailing List

Re: [Xen-ia64-devel] [Patch][RFC] allocate all memory to dom0

To: Isaku Yamahata <yamahata@xxxxxxxxxxxxx>

From: Akio Takebe <takebe_akio@xxxxxxxxxxxxxx>

Date: Thu, 05 Oct 2006 21:03:55 +0900

Cc: Tristan Gingold <Tristan.Gingold@xxxxxxxx>, xen-ia64-devel@xxxxxxxxxxxxxxxxxxx

Delivery-date: Thu, 05 Oct 2006 09:26:17 -0700

List-id: Discussion of the ia64 port of Xen <xen-ia64-devel.lists.xensource.com>

Hi, Isaku and Tristan Thank you for your comments. > >On Thu, Oct 05, 2006 at 04:55:07PM +0900, Isaku Yamahata wrote: >> On Thu, Oct 05, 2006 at 04:00:20PM +0900, Akio Takebe wrote: >> > Hi, >> > >> > Also in the case of current Xen-ia64-unstable(cset:11721), >> > this panic is occured by specified dom0_mem=4G. >> > (without my patch) >> > >> > I think the following error message is hint of this bug. >> > (XEN) Warning: UC to WB for mpaddr=f9ff0000 >> > >> > I checked the arch/ia64/xen/mm.c >> > Why changing pteval2 from UC to WB is OK? >> > If pteval2 is WB and pteval is UC, should pteval2 be changed to UC? >> > >> >> Because it's RAM. not I/O. >> >From your log >> > (XEN) dom mem: type= 7, attr=0x0000000000000008, range= >> > [0x0000000080000000-0x00000000fe000000) (2016MB) >> Probably ioremap hypercall failed. >> Please check it by adding debug message assign_domain_same_page(). >> I suppose it should complain somehow. >> >> >> The warning message is the result of Linux tries to use the addresses >> for I/O which is RAM. >> Then the next question is why/how Linux decided to use the addresses >> to map I/O. >> iomem_resource manages those regions so that such a overlap >> shouldn't happen. > >This is wrong. Linux doesn't complain. >Dom0 builder assigns RAM which overlaps with PCI I/O so that >dom0Linux can't access PCI devices. >So far no one has assigned so much memory to dom0, >this wasn't an issue. Thank you for your infomation!. I checked Linux /proc/iomem. You are right. # cat /proc/iomem [snip..] f8e00000-f8efffff : 0000:06:02.1 f8fc0000-f8fcffff : 0000:06:02.0 f8fd0000-f8fdffff : 0000:06:02.0 f8fe0000-f8feffff : 0000:06:02.1 f8ff0000-f8ffffff : 0000:06:02.1 f9000000-fbffffff : PCI Bus 0000:00 <-----------this f9ff0000-f9ff03ff : 0000:00:1d.7 f9ff0000-f9ff03ff : ehci_hcd fa000000-fbffffff : PCI Bus #01 fa000000-faffffff : 0000:01:01.0 And the below is dom0 map at dom0_mem=2G and dom0_mem=4G. dom0_mem=4G (XEN) dom mem: type=13, attr=0x8000000000000008, range=[0x0000000000000000-0x0000000000001000) (4KB) (XEN) dom mem: type=10, attr=0x8000000000000008, range=[0x0000000000001000-0x0000000000002000) (4KB) (XEN) dom mem: type= 6, attr=0x8000000000000008, range=[0x0000000000002000-0x0000000000003000) (4KB) (XEN) dom mem: type= 7, attr=0x0000000000000009, range=[0x0000000000003000-0x0000000000007000) (16KB) (XEN) dom mem: type= 7, attr=0x0000000000000009, range=[0x0000000000007000-0x0000000000009000) (8KB) (XEN) dom mem: type= 7, attr=0x0000000000000009, range=[0x0000000000009000-0x0000000000082000) (484KB) (XEN) dom mem: type= 6, attr=0x8000000000000009, range=[0x0000000000082000-0x0000000000084000) (8KB) (XEN) dom mem: type= 7, attr=0x0000000000000009, range=[0x0000000000084000-0x0000000000085000) (4KB) (XEN) dom mem: type= 7, attr=0x0000000000000009, range=[0x0000000000085000-0x00000000000a0000) (108KB) (XEN) dom mem: type= 5, attr=0x8000000000000009, range=[0x00000000000c0000-0x0000000000100000) (256KB) (XEN) dom mem: type= 7, attr=0x0000000000000008, range=[0x0000000000100000-0x000000007f708000) (2038MB) (XEN) dom mem: type= 5, attr=0x8000000000000009, range=[0x000000007f70a000-0x000000007fb00000) (3MB) (XEN) dom mem: type= 7, attr=0x0000000000000008, range=[0x000000007fb00000-0x000000007fe00000) (3MB) (XEN) dom mem: type= 5, attr=0x8000000000000009, range=[0x000000007fe00000-0x000000007fe58000) (352KB) (XEN) dom mem: type= 7, attr=0x0000000000000008, range=[0x000000007fe58000-0x000000007feb8000) (384KB) (XEN) dom mem: type= 6, attr=0x8000000000000009, range=[0x000000007feba000-0x0000000080000000) (1MB) (XEN) dom mem: type= 7, attr=0x0000000000000008, range=[0x0000000080000000-0x00000000fe000000) (2016MB) (XEN) dom mem: type=11, attr=0x0000000000000001, range=[0x00000000fe000000-0x00000000ff000000) (16MB) (XEN) dom mem: type= 6, attr=0x8000000000000001, range=[0x00000000ff000000-0x0000000100000000) (16MB) (XEN) dom mem: type= 6, attr=0x8000000000000009, range=[0x00000001ffffe000-0x0000000200000000) (8KB) (XEN) dom mem: type= 5, attr=0x8000000000000009, range=[0x00000002ffe14000-0x00000002ffe80000) (432KB) (XEN) dom mem: type= 6, attr=0x8000000000000009, range=[0x00000002fffb8000-0x0000000300000000) (288KB) (XEN) dom mem: type=11, attr=0x8000000000000001, range=[0x00000ffff8000000-0x00000ffffc000000) (64MB) (XEN) dom mem: type=12, attr=0x8000000000000001, range=[0x00000ffffc000000-0x0000100000000000) (64MB) dom0_mem=2G (XEN) dom mem: type=13, attr=0x8000000000000008, range=[0x0000000000000000-0x0000000000001000) (4KB) (XEN) dom mem: type=10, attr=0x8000000000000008, range=[0x0000000000001000-0x0000000000002000) (4KB) (XEN) dom mem: type= 6, attr=0x8000000000000008, range=[0x0000000000002000-0x0000000000003000) (4KB) (XEN) dom mem: type= 7, attr=0x0000000000000009, range=[0x0000000000003000-0x0000000000007000) (16KB) (XEN) dom mem: type= 7, attr=0x0000000000000009, range=[0x0000000000007000-0x0000000000009000) (8KB) (XEN) dom mem: type= 7, attr=0x0000000000000009, range=[0x0000000000009000-0x0000000000082000) (484KB) (XEN) dom mem: type= 6, attr=0x8000000000000009, range=[0x0000000000082000-0x0000000000084000) (8KB) (XEN) dom mem: type= 7, attr=0x0000000000000009, range=[0x0000000000084000-0x0000000000085000) (4KB) (XEN) dom mem: type= 7, attr=0x0000000000000009, range=[0x0000000000085000-0x00000000000a0000) (108KB) (XEN) dom mem: type= 5, attr=0x8000000000000009, range=[0x00000000000c0000-0x0000000000100000) (256KB) (XEN) dom mem: type= 7, attr=0x0000000000000008, range=[0x0000000000100000-0x000000007f708000) (2038MB) (XEN) dom mem: type= 5, attr=0x8000000000000009, range=[0x000000007f70a000-0x000000007fb00000) (3MB) (XEN) dom mem: type= 7, attr=0x0000000000000008, range=[0x000000007fb00000-0x000000007fe00000) (3MB) (XEN) dom mem: type= 5, attr=0x8000000000000009, range=[0x000000007fe00000-0x000000007fe58000) (352KB) (XEN) dom mem: type= 7, attr=0x0000000000000008, range=[0x000000007fe58000-0x000000007feb8000) (384KB) (XEN) dom mem: type= 6, attr=0x8000000000000009, range=[0x000000007feba000-0x0000000080000000) (1MB) (XEN) dom mem: type=11, attr=0x0000000000000001, range=[0x00000000fe000000-0x00000000ff000000) (16MB) (XEN) dom mem: type= 6, attr=0x8000000000000001, range=[0x00000000ff000000-0x0000000100000000) (16MB) (XEN) dom mem: type= 6, attr=0x8000000000000009, range=[0x00000001ffffe000-0x0000000200000000) (8KB) (XEN) dom mem: type= 5, attr=0x8000000000000009, range=[0x00000002ffe14000-0x00000002ffe80000) (432KB) (XEN) dom mem: type= 6, attr=0x8000000000000009, range=[0x00000002fffb8000-0x0000000300000000) (288KB) (XEN) dom mem: type=11, attr=0x8000000000000001, range=[0x00000ffff8000000-0x00000ffffc000000) (64MB) (XEN) dom mem: type=12, attr=0x8000000000000001, range=[0x00000ffffc000000-0x0000100000000000) (64MB) > >I think there are two right way. >A avoid overlap somehow > A.0 fake up ACPI table and assign pci somewhere. > A.1 detect pci bridge > To detect the region of pci bridge, it is necessary to parse > ACPI table. But xen doesn't have such a ACPI parser. > A.2 As a temporal work around, we can introduce xen boot option to > indicate pci io area. > A.3 assign RAM following the original MD. > This might be easy. > The current complete_dom0_memmap() seeks a gap and fill it > with RAM. modify it so that it only assigns RAM only when > a found gap is in baremetal's RAM. >B modify ioremap hypercall and linux ioremap somehow > to not use ram region. > Probably Linux ioremap() wouldn't return __IA64_UNCACHED_OFFSET|offset > so that iounmap() might need to be implemented. >C don't give so much memory to dom0 > The original motivation is to get modular vnif work. > Now xencomm has been merged, this isn't an issue anymore. > Akio, Is this right? > Yes, you are right. I have not tried to check modular vnif yet. But I have checked it with cset 11635 + Tristan's xen-xcom-[a-c]3.diffs. The results is good work. >Option C or A.3 is preferable. I don't think those are >ery good, though. Any ideas? > I also prefer A.3 to others. Best Regards, Akio Takebe _______________________________________________ Xen-ia64-devel mailing list Xen-ia64-devel@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-ia64-devel

©2013 Xen Project, A Linux Foundation Collaborative Project. All Rights Reserved.
Linux Foundation is a registered trademark of The Linux Foundation.
Xen Project is a trademark of The Linux Foundation.