----- Original Message ----- > > > > So my questions are: > > > > (1) Is it OK to use "/proc/kcore" instead of "/dev/mem" as a workaround? > > Is there any side-effect? > > As I read it, /proc/kcore is the kernel's virtual address space and > /dev/mem is the system's physical address space. It probably isn't wise > to debug the latter on any dom0 (whether nested in another > virtualization or not) except in very acute cases. It may explain the > problem you were having in the first place if VirtualBox affects whether > /dev/mem is a real physical memory view or if it doesn't then whether > VirtualBox itself affects those cases where, as I understand it, the > kernel has constant physical addresses for some things. Hi Dave, I'm not sure why /proc/kcore should be considered unwise? Even with a Xen dom0 kernel, if it works, it works. All that crash is doing is taking the physical address it normally would use for reading from /dev/mem (or /dev/crash), and turning it into a unity-mapped kernel virtual address that it reads from /proc/kcore. I might be missing something, but it would seem like the virtualization aspect would be a non-issue? /proc/kcore is a problem with 32-bit kernels, which cannot unity-map physical memory above 896MB, but even with those, the session still comes up, albeit slightly crippled. Dave -- Crash-utility mailing list Crash-utility@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/crash-utility
