Re: [Qemu-devel] [RFC] [PATCH 0/5] linux-user: refactor do_syscall()

[Richard Henderson <rth@twiddle.net>]

On 10/12/2012 11:24 AM, riku.voipio@linaro.org wrote:
> From: Riku Voipio <riku.voipio@linaro.org>
> 
> Currently linux-user handles system calls with a 3000+ line switch/case construct
> in do_syscall(). Some syscalls are implemented inline in the switch/case, others
> as separate functions, and the rest as mix of both.
> 
> As the first step of the cleanup, I'd like to move implementation of each syscall
> completely to their own functions. While at it, we define more standard interface between
> do_syscall() and the functions implementing the system calls: system call functions take
> parameter as raw abi_long, and leave the host to target errno conversion to do_syscall.

My only concern is leaving the host-to-target conversion to do_syscall.
I think the return value from do_foo should be the proper target return value.

My concern here are those handful of syscalls for which we have target-specific
error reporting mechanisms, and for which those reporting mechanisms are exploited
in some nefarious way.  E.g. sigprocmask and getpriority.


r~