Vivek Goyal <[EMAIL PROTECTED]> writes: > On Thu, Oct 12, 2006 at 06:47:08PM +0900, Magnus Damm wrote: >> Hi Vivek, >> >> This patch breaks kdump under Xen/dom0. This is because "Kernel code" >> isn't listed in /proc/iomem. The reason behind this is probably that >> the address where the kernel is loaded is in pseudo physical address >> space, and this space is not contiguously mapped 1:1 to machine >> addresses (real physical addresses in the Linux world). >> >> If we really want to pass physical addresses under Xen we need to pass >> the address of each and every page that maps the kernel. This sounds >> like a pretty redundant move IMO because the tool that parses Xen >> crash dumps needs to be (and is already) aware of this mapping anyhow. >> >> So the following (mangled) patch fixes this by warning instead of >> returning error: >> > > Magnus, I think this patch is problematic. This bypasses the > error checking mechanism in non-virtualized env. So due to some reason if > "Kernel Code" is not exported from /proc/iomem, kexec-tools will never > detect it and set the phyaddr to zero. And a kernel header will be created > with kernel virtual address X pointing to physical addr 0 which is wrong. > It should have been kernel virtual addr X pointing to physical addr 2MB > (Assuming kernel is loaded physically at 2MB addr). > > I think somehow we shall have to make kexec-tools Xen aware to take care > of Xen special cases.
Agreed. If we are running in a mode that is not fully virtualized anything running directly in that mode needs to understand that. Therefore kexec needs to understand that. If we understand we are running in a different mode we can take appropriate action. Eric _______________________________________________ fastboot mailing list [email protected] https://lists.osdl.org/mailman/listinfo/fastboot
