From 913292c97d750fe4188b4f5aa770e5e0ca1e5a91 Mon Sep 17 00:00:00 2001 From: Madhuparna Bhowmik Date: Fri, 24 Jan 2020 10:29:08 +0530 Subject: sched.h: Annotate sighand_struct with __rcu This patch fixes the following sparse errors by annotating the sighand_struct with __rcu kernel/fork.c:1511:9: error: incompatible types in comparison expression kernel/exit.c:100:19: error: incompatible types in comparison expression kernel/signal.c:1370:27: error: incompatible types in comparison expression This fix introduces the following sparse error in signal.c due to checking the sighand pointer without rcu primitives: kernel/signal.c:1386:21: error: incompatible types in comparison expression This new sparse error is also fixed in this patch. Signed-off-by: Madhuparna Bhowmik Acked-by: Paul E. McKenney Link: https://lore.kernel.org/r/20200124045908.26389-1-madhuparnabhowmik10@gmail.com Signed-off-by: Christian Brauner --- include/linux/sched.h | 2 +- kernel/signal.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 467d26046416..ef60aa15097a 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -917,7 +917,7 @@ struct task_struct { /* Signal handlers: */ struct signal_struct *signal; - struct sighand_struct *sighand; + struct sighand_struct __rcu *sighand; sigset_t blocked; sigset_t real_blocked; /* Restored if set_restore_sigmask() was used: */ diff --git a/kernel/signal.c b/kernel/signal.c index bcd46f547db3..9ad8dea93dbb 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1383,7 +1383,7 @@ struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, * must see ->sighand == NULL. */ spin_lock_irqsave(&sighand->siglock, *flags); - if (likely(sighand == tsk->sighand)) + if (likely(sighand == rcu_access_pointer(tsk->sighand))) break; spin_unlock_irqrestore(&sighand->siglock, *flags); } -- cgit v1.2.3