qemu: fatal: Trying to execute code outside RAM or ROM; worked in 1.4.0, fails in 1.4.92

I'm using qemu to run and debug the EDK2 uEFI environment. OVMF is being built out of the EDK2 tree I've checked out (r14367).  (Reproducing all this could be tedious so I am available for debugging/testing.)

qemu 1.4.0 was able to execute this guest environment with no trouble, qemu 1.4.92 however issues an error message and aborts.  The command line I use to start qemu is:

$ /usr/local/bin/qemu-system-x86_64 -m 1024 -bios OVMF.fd -monitor stdio

1.4.92 gives the following register dump:

QEMU 1.4.92 monitor - type 'help' for more information
(qemu) qemu: fatal: Trying to execute code outside RAM or ROM at 0x0000000100000000

RAX=000000003e084da8 RBX=000000003e084868 RCX=0000000000000000 RDX=000000003e084f00
RSI=0000000000000001 RDI=000000003e085000 RBP=000000003e084708 RSP=000000003fac8510
R8 =0000000000000000 R9 =000000003e14c3e3 R10=0000000000000033 R11=00000000000000d3
R12=000000003e0848a0 R13=0000000000000000 R14=0000000000000000 R15=0000000000000000
RIP=00000000ffffffe4 RFL=00000046 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=0
ES =0008 0000000000000000 ffffffff 00cf9300 DPL=0 DS   [-WA]
CS =0028 0000000000000000 ffffffff 00af9b00 DPL=0 CS64 [-RA]
SS =0008 0000000000000000 ffffffff 00cf9300 DPL=0 DS   [-WA]
DS =0008 0000000000000000 ffffffff 00cf9300 DPL=0 DS   [-WA]
FS =0008 0000000000000000 ffffffff 00cf9300 DPL=0 DS   [-WA]
GS =0008 0000000000000000 ffffffff 00cf9300 DPL=0 DS   [-WA]
LDT=0000 0000000000000000 0000ffff 00008200 DPL=0 LDT
TR =0000 0000000000000000 0000ffff 00008b00 DPL=0 TSS64-busy
GDT=     000000003fa50e98 0000003f
IDT=     000000003f9d6e20 00000fff
CR0=80000033 CR2=0000000000000000 CR3=000000003fa67000 CR4=00000668
...


Questions:
1) Is this problem relevant?  (is full backward compatability to be supported?)
2) Are there new guest execution controls in 1.4.9x that might cause this?
3) If #2, can they be disabled by a qemu command line switch?
4) If not #2, in what qemu source file specifically can I find the logic causing the abort? (help me help you :)
5) If guest memory is corrupted or improperly mapped, how can I keep qemu alive to examime/dump guest memory?