diff options
| author | Richard Weinberger <rw@linutronix.de> | 2011-12-12 14:35:56 +0100 |
|---|---|---|
| committer | Clark Williams <williams@redhat.com> | 2012-01-16 13:00:34 -0600 |
| commit | aa6e4bffa4838c1829adbd82a58f72f1bb0ddcf2 (patch) | |
| tree | 1d84a52ddb7dc4e4f4d4bfeefe4f80916ed799f3 | |
| parent | d88ae76dca0ebba795c25a536116096a31195fba (diff) | |
printk: Disable migration instead of preemption
There is no need do disable preemption in vprintk(), disable_migrate()
is sufficient. This fixes the following bug in -rt:
[ 14.759233] BUG: sleeping function called from invalid context
at /home/rw/linux-rt/kernel/rtmutex.c:645
[ 14.759235] in_atomic(): 1, irqs_disabled(): 0, pid: 547, name: bash
[ 14.759244] Pid: 547, comm: bash Not tainted 3.0.12-rt29+ #3
[ 14.759246] Call Trace:
[ 14.759301] [<ffffffff8106fade>] __might_sleep+0xeb/0xf0
[ 14.759318] [<ffffffff810ad784>] rt_spin_lock_fastlock.constprop.9+0x21/0x43
[ 14.759336] [<ffffffff8161fef0>] rt_spin_lock+0xe/0x10
[ 14.759354] [<ffffffff81347ad1>] serial8250_console_write+0x81/0x121
[ 14.759366] [<ffffffff8107ecd3>] __call_console_drivers+0x7c/0x93
[ 14.759369] [<ffffffff8107ef31>] _call_console_drivers+0x5c/0x60
[ 14.759372] [<ffffffff8107f7e5>] console_unlock+0x147/0x1a2
[ 14.759374] [<ffffffff8107fd33>] vprintk+0x3ea/0x462
[ 14.759383] [<ffffffff816160e0>] printk+0x51/0x53
[ 14.759399] [<ffffffff811974e4>] ? proc_reg_poll+0x9a/0x9a
[ 14.759403] [<ffffffff81335b42>] __handle_sysrq+0x50/0x14d
[ 14.759406] [<ffffffff81335c8a>] write_sysrq_trigger+0x4b/0x53
[ 14.759408] [<ffffffff81335c3f>] ? __handle_sysrq+0x14d/0x14d
[ 14.759410] [<ffffffff81197583>] proc_reg_write+0x9f/0xbe
[ 14.759426] [<ffffffff811497ec>] vfs_write+0xac/0xf3
[ 14.759429] [<ffffffff8114a9b3>] ? fget_light+0x3a/0x9b
[ 14.759431] [<ffffffff811499db>] sys_write+0x4a/0x6e
[ 14.759438] [<ffffffff81625d52>] system_call_fastpath+0x16/0x1b
Signed-off-by: Richard Weinberger <rw@linutronix.de>
Link: http://lkml.kernel.org/r/1323696956-11445-1-git-send-email-rw@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | kernel/printk.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/printk.c b/kernel/printk.c index fad23c88bf6e..13ea6a9a7ce6 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -901,7 +901,7 @@ asmlinkage int vprintk(const char *fmt, va_list args) boot_delay_msec(); printk_delay(); - preempt_disable(); + migrate_disable(); /* This stops the holder of console_sem just where we want him */ raw_local_irq_save(flags); this_cpu = smp_processor_id(); @@ -1032,7 +1032,7 @@ asmlinkage int vprintk(const char *fmt, va_list args) out_restore_irqs: raw_local_irq_restore(flags); - preempt_enable(); + migrate_enable(); return printed_len; } EXPORT_SYMBOL(printk); |