From: Anton Vorontsov <anton.vorontsov@linaro.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Greg KH <gregkh@linuxfoundation.org>,
KOSAKI Motohiro <kosaki.motohiro@gmail.com>,
"Eric W. Biederman" <ebiederm@xmission.com>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Paul Mundt <lethal@linux-sh.org>,
Russell King <linux@arm.linux.org.uk>,
Mike Frysinger <vapier@gentoo.org>,
Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Richard Weinberger <richard@nod.at>,
linux-kernel@vger.kernel.org
Subject: [PATCH 7/8] um: Should hold tasklist_lock while traversing processes
Date: Tue, 7 Feb 2012 10:51:20 +0400 [thread overview]
Message-ID: <20120207065120.GG1496@oksana.dev.rtsoft.ru> (raw)
In-Reply-To: <20120207064809.GA29061@oksana.dev.rtsoft.ru>
Traversing the tasks requires holding tasklist_lock, otherwise it
is unsafe.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
---
p.s. However, I'm not sure that calling os_kill_ptraced_process()
in the 'atomic' context is correct. It seem to work, but please
take a closer look.
arch/um/kernel/reboot.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/arch/um/kernel/reboot.c b/arch/um/kernel/reboot.c
index 4d93dff..66d754c 100644
--- a/arch/um/kernel/reboot.c
+++ b/arch/um/kernel/reboot.c
@@ -4,6 +4,7 @@
*/
#include "linux/sched.h"
+#include "linux/spinlock.h"
#include "linux/slab.h"
#include "kern_util.h"
#include "os.h"
@@ -22,6 +23,7 @@ static void kill_off_processes(void)
struct task_struct *p;
int pid;
+ read_lock(&tasklist_lock);
for_each_process(p) {
if (p->mm == NULL)
continue;
@@ -29,6 +31,7 @@ static void kill_off_processes(void)
pid = p->mm->context.id.u.pid;
os_kill_ptraced_process(pid, 1);
}
+ read_unlock(&tasklist_lock);
}
}
--
1.7.7.6
next prev parent reply other threads:[~2012-02-07 6:51 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-07 6:48 [PATCH 0/8] Fixes for common mistakes w/ for_each_process and task->mm Anton Vorontsov
2012-02-07 6:49 ` [PATCH 1/8] sysrq: Fix possible race with exiting task Anton Vorontsov
2012-02-09 1:47 ` David Rientjes
2012-02-07 6:49 ` [PATCH 2/8] sysrq: Properly check for kernel threads Anton Vorontsov
2012-02-09 1:46 ` David Rientjes
2012-02-07 6:50 ` [PATCH 3/8] arm: Fix possible race on task->mm Anton Vorontsov
2012-02-08 16:08 ` Oleg Nesterov
2012-02-09 15:33 ` Anton Vorontsov
2012-02-09 15:43 ` Anton Vorontsov
2012-02-10 20:21 ` Oleg Nesterov
2012-02-09 1:46 ` David Rientjes
2012-02-07 6:50 ` [PATCH 4/8] powerpc/mm: " Anton Vorontsov
2012-02-07 6:50 ` [PATCH 5/8] sh: " Anton Vorontsov
2012-02-07 6:50 ` [PATCH 6/8] blackfin: " Anton Vorontsov
2012-02-08 16:20 ` Oleg Nesterov
2012-02-07 6:51 ` Anton Vorontsov [this message]
2012-02-07 6:51 ` [PATCH 8/8] um: " Anton Vorontsov
2012-02-08 15:59 ` [PATCH 0/8] Fixes for common mistakes w/ for_each_process and task->mm Oleg Nesterov
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