Hi Jeff,

We really like the *WithMRs functions and there is no plan to get rid of them. Support for the syscall stub generator using them was removed here (https://github.com/seL4/seL4/commit/5271925ba54639b849261e652e73ab56ee243fb2).

Not being able to get error information after doing an invocation is unacceptable as a default. I suppose if you have an application where you *know* you won't need the error information then you might want to re-enable this.

Ideally we come up with some better stub generation that doesn't throw away the errors.

Adrian

On Thu 27-Oct-2016 10:14 AM, Jeff Waugh wrote:

Hi all,

Last night I opened two pull requests to begin fixing the CallWithMRs code path on x86_64 and aarch32.

syscall_stub_gen.py couldn't generate x86_64 stubs for the CallWithMRs / non-IPCBuffer path. That didn't surprise me too much, as x86_64 support is relatively new.

Then I discovered that libsel4 *always* [1] uses the IPCBuffer path. Hrm.

Changing that prompted a quick fix to aarch32's apparently unused, long since even built CallWithMRs. (Similar fixes might be needed in some of the other functions.)

The test suite failed with it on aarch32, which I could poke at in more depth, but it worked fine for x86_64.

So… what's the status of the *WithMRs functions? Based on my understanding of the source (particularly the new helper functions) and assembly output, they're destined for the chopping block, right?

Thanks,

Jeff

[1] hard coded --buffer parameter to syscall_stub_gen.py in libsel4/Makefile, since late 2015
_______________________________________________
Devel mailing list
Devel@sel4.systems
https://sel4.systems/lists/listinfo/devel