On 08/05/13 15:02, Borislav Petkov wrote: > On Mon, Aug 05, 2013 at 01:27:16PM +0200, Laszlo Ersek wrote: >>> --- before 2013-07-31 22:20:52.316039492 +0200 >>> +++ after 2013-07-31 22:21:30.960731706 +0200 >>> @@ -9,7 +9,7 @@ efi: mem07: type=2, attr=0xf, range=[0x0 >>> efi: mem08: type=7, attr=0xf, range=[0x0000000040000000-0x000000007c000000) (960MB) >>> efi: mem09: type=4, attr=0xf, range=[0x000000007c000000-0x000000007c020000) (0MB) >>> efi: mem10: type=7, attr=0xf, range=[0x000000007c020000-0x000000007e0ad000) (32MB) >>> -efi: mem11: type=4, attr=0xf, range=[0x000000007e0ad000-0x000000007e0cc000) (0MB) >>> +efi: mem11: type=4, attr=0xf, range=[0x000000007e0ad000-0x000000007e0ad000) (0MB) >> >> (type 4 is EfiBootServicesData) > > Yes. > >>> efi: mem12: type=7, attr=0xf, range=[0x000000007e0cc000-0x000000007e0cd000) (0MB) >>> efi: mem13: type=4, attr=0xf, range=[0x000000007e0cd000-0x000000007e55d000) (4MB) >>> efi: mem14: type=3, attr=0xf, range=[0x000000007e55d000-0x000000007e59c000) (0MB) >>> >>> That second boundary of region mem11 suddenly changes *before* we merge >>> the regions. edk2 bug? >> >> I take it you mean this change (ie. appearance of the zero-sized range) >> occurs when you enable KVM acceleration in qemu? > > Right. And I'm booting with qemu -enable-kvm so KVM acceleration is > enabled?? Or do you mean something else. My question was: is my understanding correct that you only see this problem with "-enable-kvm"? Because, On 08/01/13 18:49, Borislav Petkov wrote: > so I'm seeing this funny thing where an EFI region changes when we > enter efi_enter_virtual_mode when booting with edk2 on kvm. Here's > the diff: You said "on kvm", and provided a diff. I think (hope) I understand the environment you've denoted with "after", but what's your "before"? The absence of "-enable-kvm", or something else? > >> If so, please locate "gEfiMdePkgTokenSpaceGuid.PcdDebugPrintErrorLevel" >> in OvmfPkg/OvmfPkgX64.dsc, and set the following bit in its value: >> >> # DEBUG_GCD 0x00100000 Global Coherency Database changes >> >> Then please rebuild OVMF, and capture the debug port output of qemu >> ("-debugcon file:debug.log -global isa-debugcon.iobase=0x402") both with >> and without KVM. >> >> DEBUG_GCD should produce messages related to CoreAllocateSpace(), and >> might help us find the spot the difference is introduced. > > Ok, I'll try to get this thing done before my vacation. If not, we'll > deal with it afterwards but I won't forget, I promise! :-) > >> BTW does this have anything to do with the NX bit report of yours, or >> have you noticed this independently? > > Independently, while testing my runtime services mapping patchset. What's the purpose of that series? Can you please provide a link (if you posted versions of it already)? > I was > getting an empty region and was wondering whether to discard it from the > mapping or not and then I looked at why I get it in the first place. > > Basically, I get this empty region which appears at some point. It is > there when we enter efi_enter_virtual_mode in the kernel to setup the > runtime mappings: > > [ 0.005012] efi: efi_enter_virtual_mode: enter > [ 0.006004] efi: mem00: type=7, attr=0xf, range=[0x0000000000000000-0x000000000009f000) (0MB) > [ 0.007004] efi: mem01: type=2, attr=0xf, range=[0x000000000009f000-0x00000000000a0000) (0MB) > [ 0.008003] efi: mem02: type=7, attr=0xf, range=[0x0000000000100000-0x0000000000800000) (7MB) > [ 0.009004] efi: mem03: type=4, attr=0xf, range=[0x0000000000800000-0x0000000001000000) (8MB) > [ 0.010004] efi: mem04: type=7, attr=0xf, range=[0x0000000001000000-0x0000000002000000) (16MB) > [ 0.011004] efi: mem05: type=2, attr=0xf, range=[0x0000000002000000-0x00000000036e3000) (22MB) > [ 0.012004] efi: mem06: type=7, attr=0xf, range=[0x00000000036e3000-0x000000003fffb000) (969MB) > [ 0.013003] efi: mem07: type=2, attr=0xf, range=[0x000000003fffb000-0x0000000040000000) (0MB) > [ 0.014004] efi: mem08: type=7, attr=0xf, range=[0x0000000040000000-0x000000007c000000) (960MB) > [ 0.015004] efi: mem09: type=4, attr=0xf, range=[0x000000007c000000-0x000000007c020000) (0MB) > [ 0.016004] efi: mem10: type=7, attr=0xf, range=[0x000000007c020000-0x000000007e0ad000) (32MB) > [ 0.017004] efi: mem11: type=4, attr=0xf, range=[0x000000007e0ad000-0x000000007e0ad000) (0MB) > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > [ 0.018003] efi: mem12: type=7, attr=0xf, range=[0x000000007e0cc000-0x000000007e0cd000) (0MB) > > When we dump the EFI regions initially, it is ok. > > [ 0.000000] efi: mem10: type=7, attr=0xf, range=[0x000000007c020000-0x000000007e0ad000) (32MB) > [ 0.000000] efi: mem11: type=4, attr=0xf, range=[0x000000007e0ad000-0x000000007e0cc000) (0MB) > [ 0.000000] efi: mem12: type=7, attr=0xf, range=[0x000000007e0cc000-0x000000007e0cd000) (0MB) > > So what basically happens is the end boundary of the region becomes the > start, practically turning it into a 0-size one. ... and you guys suspect that some firmware code is responsible, code that runs between the initial memory map dump, and efi_enter_virtual_mode(): https://lkml.org/lkml/2013/7/31/550 > Thanks for looking into it. Hopefully DEBUG_GCD will tell us something. Thanks Laszlo -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html