RISC-V: Add support for restartable sequence

Add calls to rseq_signal_deliver() and rseq_syscall() to introduce RSEQ
support.

1. Call the rseq_signal_deliver() function to fixup on the pre-signal
   frame when a signal is delivered on top of a restartable sequence
   critical section.

2. Check that system calls are not invoked from within rseq critical
   sections by invoking rseq_signal() from ret_from_syscall(). With
   CONFIG_DEBUG_RSEQ, such behavior results in termination of the
   process with SIGSEGV.

Signed-off-by: Vincent Chen <[email protected]>
Reviewed-by: Mathieu Desnoyers <[email protected]>
Signed-off-by: Palmer Dabbelt <[email protected]>

0 files changed, 0 insertions, 0 deletions