On 24 February 2015 at 20:59, Richard W.M. Jones <rjones@xxxxxxxxxx> wrote: > > https://bugzilla.redhat.com/show_bug.cgi?id=1194366 > > Has anyone seen this KVM error? Or have suggestions how to debug it > further? > > kvm [2028]: load/store instruction decoding not implemented This is a fairly common thing to run into and google is bound to have references to past discussions. What has happened here is that the guest has attempted a "complex" load/store instruction to an area of RAM which is not mapped (ie not guest RAM). For this class of instructions the hardware doesn't provide syndrome information to allow us to figure out the address/size etc of the access, so we would have to actually decode the offending instruction and emulate it; this emulation isn't implemented. Complex insns are things like load-multiple (there's a complete list in the ARM ARM somewhere). Generally this indicates a guest bug because you really shouldn't be accessing devices with weird instructions like that (and you shouldn't be accessing unmapped memory at all). At some point we might actually implement the decoding, which will probably just mean your guest crashes inside the VM rather than outside it. > Qemu prints this before crashing: > > error: kvm run failed Function not implemented > (followed by a register dump) That's not a QEMU crash, it's QEMU exiting noisily. You can use the register dump info in combination with the kernel address map to find out exactly what was trying the access that failed. (Maybe we should add a line to that dump saying "this is not a QEMU crash" because it's kinda misleading :-)) -- PMM _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
