diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2012-02-27 12:58:59 +0000 |
|---|---|---|
| committer | Arnd Bergmann <arnd@arndb.de> | 2012-02-27 12:59:03 +0000 |
| commit | d0cdd82c6e0944df733b28f5d4cbbe97298587e4 (patch) | |
| tree | 9de205625a4657fedbfae52c65ea017beb7509a8 /kernel/exit.c | |
| parent | 747303a383d59a4d4667152fb68293dd9ff06438 (diff) | |
| parent | 9418ba306688c0b77a8548b3281ba3d130036516 (diff) | |
Merge branch 'imx-fixes' of git://git.pengutronix.de/git/imx/linux-2.6 into next/fixes-non-critical
* 'imx-fixes' of git://git.pengutronix.de/git/imx/linux-2.6: (247 commits)
ARM: mach-imx: mx3: Fix section mismatch in imx3_init_l2x0()
ARM: imx_v4_v5_defconfig: Fix the selection of 32 bit flash support for iMX21ADS board
ARM: mach-pcm038: Fix field name of regulator_consumer_supply struct
Also includes an update to v3.3-rc3
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'kernel/exit.c')
| -rw-r--r-- | kernel/exit.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/kernel/exit.c b/kernel/exit.c index 294b1709170..4b4042f9bc6 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -1038,6 +1038,22 @@ void do_exit(long code) if (tsk->nr_dirtied) __this_cpu_add(dirty_throttle_leaks, tsk->nr_dirtied); exit_rcu(); + + /* + * The setting of TASK_RUNNING by try_to_wake_up() may be delayed + * when the following two conditions become true. + * - There is race condition of mmap_sem (It is acquired by + * exit_mm()), and + * - SMI occurs before setting TASK_RUNINNG. + * (or hypervisor of virtual machine switches to other guest) + * As a result, we may become TASK_RUNNING after becoming TASK_DEAD + * + * To avoid it, we have to wait for releasing tsk->pi_lock which + * is held by try_to_wake_up() + */ + smp_mb(); + raw_spin_unlock_wait(&tsk->pi_lock); + /* causes final put_task_struct in finish_task_switch(). */ tsk->state = TASK_DEAD; tsk->flags |= PF_NOFREEZE; /* tell freezer to ignore us */ |