Commit 7e200490 authored by Mathieu Desnoyers's avatar Mathieu Desnoyers Committed by Guo Ren
Browse files

Revert "csky: Add support for restartable sequence" 

This reverts commit 9866d141.

The csky rseq support has been merged without ever notifying the rseq
maintainers, and without any of the required asssembler glue in the rseq
selftests, which means it is entirely untested.

It is also derived from a non-upstream riscv patch which has known bugs.

The assembly part of this revert should be carefully reviewed by the
architecture maintainer because it touches code which has changed since
the merge of the reverted patch.

The rseq selftests assembly glue should be introduced at the same time
as the architecture rseq support. Without the presence of any test, I
recommend reverting rseq support from csky for now.

Link: https://lore.kernel.org/lkml/1257037909.25426.1626705790861.JavaMail.zimbra@efficios.com/


Signed-off-by: default avatarMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: default avatarGuo Ren <guoren@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-csky@vger.kernel.org
parent c5e7ee72

arch/csky/Kconfig

+0 −1
Original line number Diff line number Diff line
@@ -94,7 +94,6 @@ config CSKY 
	select HAVE_PERF_USER_STACK_DUMP

	select HAVE_DMA_CONTIGUOUS

	select HAVE_REGS_AND_STACK_ACCESS_API

	select HAVE_RSEQ

	select HAVE_STACKPROTECTOR

	select HAVE_SYSCALL_TRACEPOINTS

	select MAY_HAVE_SPARSE_IRQ

arch/csky/kernel/entry.S

+0 −4
Original line number Diff line number Diff line
@@ -50,10 +50,6 @@ ENTRY(csky_systemcall) 
	SAVE_ALL TRAP0_SIZE

	zero_fp

	context_tracking

#ifdef CONFIG_RSEQ_DEBUG

	mov     a0, sp

	jbsr    rseq_syscall

#endif

	psrset  ee, ie



	lrw     r9, __NR_syscalls

arch/csky/kernel/signal.c

+0 −2
Original line number Diff line number Diff line
@@ -179,8 +179,6 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) 
	sigset_t *oldset = sigmask_to_save();

	int ret;



	rseq_signal_deliver(ksig, regs);



	/* Are we from a system call? */

	if (in_syscall(regs)) {

		/* Avoid additional syscall restarting via ret_from_exception */