arm64: syscall: Pass 'orig_x0' as first argument to native system call

syscall_get_arguments() returns 'regs->orig_x0' for the first system
call argument so as to avoid aliasing with the syscall return value in
'regs->regs[0]' on the return path, however the actual syscall
invocation passes 'regs->regs[0]' as the first parameter.

Although the two registers should be kept in sync during syscall entry
for native tasks, pass 'regs->orig_x0' as the first syscall parameter
for consistency with the syscall argument APIs. Compat tasks continue to
use 'regs->regs[0]' for compatibility with the behaviour of the 32-bit
kernel.

Suggested-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Will Deacon <will@kernel.org>

0 files changed, 0 insertions, 0 deletions