Laurent Vivier wrote: > This patch corrects some errors appearing when we have an emulation failure > on an operation using REP prefix. > > When x86_emulate_insn() fails, saving EIP and ECX is not enough as emulation > should have modified other registers like RSI or RDI. Moreover, the emulation > can fail on the writeback, and in this case we are not able to restore > registers. > > This patch takes another approach: at the beginning of x86_emulate_insn() we > restore state we have at end of x86_decode_insn(). To do that, we store EIP in > a new field in decode_cache, decode_eip. This field store the EIP as it is at > the end of x86_decode_insn(); and at beginning of x86_emulate_insn(), we > restore > all registers as they are in vcpu. We can do that, because the > x86_decode_insn() > doesn't modify registers (except EIP). >
How about doing it slightly differently: keep c->eip at its current meaning, and add c->eip_orig to revert to? That will make the patch smaller and reduce the changes of something being missed. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
