[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Xen-devel] Re: [PATCH][HVM] Inject #GP for un-emulated instructions rather than crash guest
- To: "Cui, Dexuan" <dexuan.cui@xxxxxxxxx>, xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
- From: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>
- Date: Tue, 27 Nov 2007 07:55:16 +0000
- Delivery-date: Mon, 26 Nov 2007 23:49:58 -0800
- List-id: Xen developer discussion <xen-devel.lists.xensource.com>
- Thread-index: AcgwqGajcxL9lyZSSkG/2aFRcODxtwABFqOQAAeF6yc=
- Thread-topic: [PATCH][HVM] Inject #GP for un-emulated instructions rather than crash guest
Okay, but would #UD be a better exception to deliver in this case? Less
overloaded than #GP and more appropriate?
On 27/11/07 04:37, "Cui, Dexuan" <dexuan.cui@xxxxxxxxx> wrote:
> The CrashMe stress test (a process repeatedly forks child processes, and
> the child processes initialize a buffer with random numbers, then treat
> the buffer as code, and execute it) can crash 32-bit HVM RHEL5.1 guest
> easily; this is because we haven't emulated all the instructions in
> handle_mmio() yet.
> The CrashMe process runs with root rights, and can access MMIO space in
> an unknown way ("strace -f" shows the random codes running at CPL=3
> don't call mmap(), and don't open any special files in /dev/ "); the gpa
> may look like 0xa**** or 0xb****, or 0xfee0****.
> After running CrashMe for several hours, I have found 24 un-emulated
> instructions may be hit...
> This patch may serve as a workaround.
> Signed-off-by: Dexuan Cui <dexuan.cui@xxxxxxxxx>
Xen-devel mailing list