[PATCH] h8300: fix syscall restarting

From: Mark Rutland
Date: Mon Sep 19 2016 - 06:33:42 EST


Back in commit f56141e3e2d9aabf ("all arches, signal: move restart_block
to struct task_struct"), all architectures and core code were changed to
use task_struct::restart_block. However, when h8300 support was
subsequently restored in v4.2, it was not updated to account for this,
and maintains thread_info::restart_block, which is not kept in sync.

This patch drops the redundant restart_block from thread_info, and moves
h8300 to the common one in task_struct, ensuring that syscall restarting
always works as expected.

Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v4.2+
---
arch/h8300/include/asm/thread_info.h | 4 ----
arch/h8300/kernel/signal.c | 2 +-
2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/h8300/include/asm/thread_info.h b/arch/h8300/include/asm/thread_info.h
index b408fe6..3cef068 100644
--- a/arch/h8300/include/asm/thread_info.h
+++ b/arch/h8300/include/asm/thread_info.h
@@ -31,7 +31,6 @@ struct thread_info {
int cpu; /* cpu we're on */
int preempt_count; /* 0 => preemptable, <0 => BUG */
mm_segment_t addr_limit;
- struct restart_block restart_block;
};

/*
@@ -44,9 +43,6 @@ struct thread_info {
.cpu = 0, \
.preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
- .restart_block = { \
- .fn = do_no_restart_syscall, \
- }, \
}

#define init_thread_info (init_thread_union.thread_info)
diff --git a/arch/h8300/kernel/signal.c b/arch/h8300/kernel/signal.c
index ad1f81f..7138303 100644
--- a/arch/h8300/kernel/signal.c
+++ b/arch/h8300/kernel/signal.c
@@ -79,7 +79,7 @@ restore_sigcontext(struct sigcontext *usc, int *pd0)
unsigned int er0;

/* Always make any pending restarted system calls return -EINTR */
- current_thread_info()->restart_block.fn = do_no_restart_syscall;
+ current->restart_block.fn = do_no_restart_syscall;

/* restore passed registers */
#define COPY(r) do { err |= get_user(regs->r, &usc->sc_##r); } while (0)
--
1.9.1