[PATCH] arm: kprobe: replace patch_lock to raw lock

[PATCH] arm: kprobe: replace patch_lock to raw lock

[Yang Shi]

When running kprobe on -rt kernel, the below bug is caught:

BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:931
in_atomic(): 1, irqs_disabled(): 128, pid: 14, name: migration/0
INFO: lockdep is turned off.
irq event stamp: 238
hardirqs last enabled at (237): [<80b5aecc>] _raw_spin_unlock_irqrestore+0x88/0x90
hardirqs last disabled at (238): [<80b56d88>] __schedule+0xec/0x94c
softirqs last enabled at (0): [<80225584>] copy_process.part.5+0x30c/0x1994
softirqs last disabled at (0): [< (null)>] (null)
Preemption disabled at:[<802f2b98>] cpu_stopper_thread+0xc0/0x140

CPU: 0 PID: 14 Comm: migration/0 Tainted: G O 4.8.3-rt2 #1
Hardware name: Freescale LS1021A
[<80212e7c>] (unwind_backtrace) from [<8020cd2c>] (show_stack+0x20/0x24)
[<8020cd2c>] (show_stack) from [<80689e14>] (dump_stack+0xa0/0xcc)
[<80689e14>] (dump_stack) from [<8025a43c>] (___might_sleep+0x1b8/0x2a4)
[<8025a43c>] (___might_sleep) from [<80b5b324>] (rt_spin_lock+0x34/0x74)
[<80b5b324>] (rt_spin_lock) from [<80b5c31c>] (__patch_text_real+0x70/0xe8)
[<80b5c31c>] (__patch_text_real) from [<80b5c3ac>] (patch_text_stop_machine+0x18/0x20)
[<80b5c3ac>] (patch_text_stop_machine) from [<802f2920>] (multi_cpu_stop+0xfc/0x134)
[<802f2920>] (multi_cpu_stop) from [<802f2ba0>] (cpu_stopper_thread+0xc8/0x140)
[<802f2ba0>] (cpu_stopper_thread) from [<802563a4>] (smpboot_thread_fn+0x1a4/0x354)
[<802563a4>] (smpboot_thread_fn) from [<80251d38>] (kthread+0x104/0x11c)
[<80251d38>] (kthread) from [<80207f70>] (ret_from_fork+0x14/0x24)

Since patch_text_stop_machine() is called in stop_machine() which disables IRQ,
sleepable lock should be not used in this atomic context, so replace patch_lock
to raw lock.

Signed-off-by: Yang Shi <yang.shi@linaro.org>
---
 arch/arm/kernel/patch.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/arm/kernel/patch.c b/arch/arm/kernel/patch.c
index 69bda1a..1f665ac 100644
--- a/arch/arm/kernel/patch.c
+++ b/arch/arm/kernel/patch.c
@@ -15,7 +15,7 @@ struct patch {
 	unsigned int insn;
 };
 
-static DEFINE_SPINLOCK(patch_lock);
+static DEFINE_RAW_SPINLOCK(patch_lock);
 
 static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags)
 	__acquires(&patch_lock)
@@ -32,7 +32,7 @@ static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags)
 		return addr;
 
 	if (flags)
-		spin_lock_irqsave(&patch_lock, *flags);
+		raw_spin_lock_irqsave(&patch_lock, *flags);
 	else
 		__acquire(&patch_lock);
 
@@ -47,7 +47,7 @@ static void __kprobes patch_unmap(int fixmap, unsigned long *flags)
 	clear_fixmap(fixmap);
 
 	if (flags)
-		spin_unlock_irqrestore(&patch_lock, *flags);
+		raw_spin_unlock_irqrestore(&patch_lock, *flags);
 	else
 		__release(&patch_lock);
 }
-- 
2.0.2

[PATCH] arm: kprobe: replace patch_lock to raw lock

[Sebastian Andrzej Siewior]

On 2016-11-10 16:17:55 [-0800], Yang Shi wrote:
> 
> Since patch_text_stop_machine() is called in stop_machine() which disables IRQ,
> sleepable lock should be not used in this atomic context, so replace patch_lock
> to raw lock.

I am taking this one. Thank you.
We have jump_labels() deactivated on ARM because stop_machine() may
cause latencies at runtime. kprobe and kgdb is used by the user on
purpose (and not because he changed some sched setting) I think we are
fine. I am going to document this.

> Signed-off-by: Yang Shi <yang.shi@linaro.org>

Sebastian

[PATCH] arm: kprobe: replace patch_lock to raw lock

[Sebastian Andrzej Siewior]

On 2016-11-10 16:17:55 [-0800], Yang Shi wrote:
> 
> Since patch_text_stop_machine() is called in stop_machine() which disables IRQ,
> sleepable lock should be not used in this atomic context, so replace patch_lock
> to raw lock.
> 
> Signed-off-by: Yang Shi <yang.shi@linaro.org>

This can also go upstream.
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

Sebastian

[PATCH] arm: kprobe: replace patch_lock to raw lock

[Shi, Yang]

On 12/1/2016 6:13 AM, Sebastian Andrzej Siewior wrote:
> On 2016-11-10 16:17:55 [-0800], Yang Shi wrote:
>>
>> Since patch_text_stop_machine() is called in stop_machine() which disables IRQ,
>> sleepable lock should be not used in this atomic context, so replace patch_lock
>> to raw lock.
>>
>> Signed-off-by: Yang Shi <yang.shi@linaro.org>
>
> This can also go upstream.
> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

Yes, thanks for acking.

Russell,

Could you please consider this patch?

Thanks,
Yang

>
> Sebastian
>

[PATCH] arm: Convert arm boot_lock to raw

[Sebastian Andrzej Siewior]

From: Frank Rowand <frank.rowand@am.sony.com>

The arm boot_lock is used by the secondary processor startup code.  The locking
task is the idle thread, which has idle->sched_class == &idle_sched_class.
idle_sched_class->enqueue_task == NULL, so if the idle task blocks on the
lock, the attempt to wake it when the lock becomes available will fail:

try_to_wake_up()
   ...
      activate_task()
         enqueue_task()
            p->sched_class->enqueue_task(rq, p, flags)

Fix by converting boot_lock to a raw spin lock.

Cc: "Andreas F?rber" <afaerber@suse.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Wei Xu <xuwei5@hisilicon.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Andy Gross <andy.gross@linaro.org>
Cc: David Brown <david.brown@linaro.org>
Cc: Viresh Kumar <vireshk@kernel.org>
Cc: Shiraz Hashim <shiraz.linux.kernel@gmail.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-samsung-soc at vger.kernel.org
Cc: linux-omap at vger.kernel.org
Cc: linux-arm-msm at vger.kernel.org
Cc: linux-soc at vger.kernel.org
Signed-off-by: Frank Rowand <frank.rowand@am.sony.com>
Link: http://lkml.kernel.org/r/4E77B952.3010606 at am.sony.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bigeasy: added new boot_lock user]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 arch/arm/mach-actions/platsmp.c   |    6 +++---
 arch/arm/mach-exynos/platsmp.c    |   12 ++++++------
 arch/arm/mach-hisi/platmcpm.c     |   22 +++++++++++-----------
 arch/arm/mach-omap2/omap-smp.c    |   10 +++++-----
 arch/arm/mach-prima2/platsmp.c    |   10 +++++-----
 arch/arm/mach-qcom/platsmp.c      |   10 +++++-----
 arch/arm/mach-spear/platsmp.c     |   10 +++++-----
 arch/arm/mach-sti/platsmp.c       |   10 +++++-----
 arch/arm/mach-sunxi/mc_smp.c      |   20 ++++++++++----------
 arch/arm/plat-versatile/platsmp.c |   10 +++++-----
 10 files changed, 60 insertions(+), 60 deletions(-)

--- a/arch/arm/mach-actions/platsmp.c
+++ b/arch/arm/mach-actions/platsmp.c
@@ -39,7 +39,7 @@ static void __iomem *sps_base_addr;
 static void __iomem *timer_base_addr;
 static int ncores;
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 void owl_secondary_startup(void);
 
@@ -93,7 +93,7 @@ static int s500_smp_boot_secondary(unsig
 
 	udelay(10);
 
-	spin_lock(&boot_lock);
+	raw_spin_lock(&boot_lock);
 
 	smp_send_reschedule(cpu);
 
@@ -106,7 +106,7 @@ static int s500_smp_boot_secondary(unsig
 	writel(0, timer_base_addr + OWL_CPU1_ADDR + (cpu - 1) * 4);
 	writel(0, timer_base_addr + OWL_CPU1_FLAG + (cpu - 1) * 4);
 
-	spin_unlock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 
 	return 0;
 }
--- a/arch/arm/mach-exynos/platsmp.c
+++ b/arch/arm/mach-exynos/platsmp.c
@@ -224,7 +224,7 @@ static void __iomem *scu_base_addr(void)
 	return (void __iomem *)(S5P_VA_SCU);
 }
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 static void exynos_secondary_init(unsigned int cpu)
 {
@@ -237,8 +237,8 @@ static void exynos_secondary_init(unsign
 	/*
 	 * Synchronise with the boot thread.
 	 */
-	spin_lock(&boot_lock);
-	spin_unlock(&boot_lock);
+	raw_spin_lock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 }
 
 int exynos_set_boot_addr(u32 core_id, unsigned long boot_addr)
@@ -302,7 +302,7 @@ static int exynos_boot_secondary(unsigne
 	 * Set synchronisation state between this boot processor
 	 * and the secondary one
 	 */
-	spin_lock(&boot_lock);
+	raw_spin_lock(&boot_lock);
 
 	/*
 	 * The secondary processor is waiting to be released from
@@ -329,7 +329,7 @@ static int exynos_boot_secondary(unsigne
 
 		if (timeout == 0) {
 			printk(KERN_ERR "cpu1 power enable failed");
-			spin_unlock(&boot_lock);
+			raw_spin_unlock(&boot_lock);
 			return -ETIMEDOUT;
 		}
 	}
@@ -375,7 +375,7 @@ static int exynos_boot_secondary(unsigne
 	 * calibrations, then wait for it to finish
 	 */
 fail:
-	spin_unlock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 
 	return pen_release != -1 ? ret : 0;
 }
--- a/arch/arm/mach-hisi/platmcpm.c
+++ b/arch/arm/mach-hisi/platmcpm.c
@@ -61,7 +61,7 @@
 
 static void __iomem *sysctrl, *fabric;
 static int hip04_cpu_table[HIP04_MAX_CLUSTERS][HIP04_MAX_CPUS_PER_CLUSTER];
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 static u32 fabric_phys_addr;
 /*
  * [0]: bootwrapper physical address
@@ -113,7 +113,7 @@ static int hip04_boot_secondary(unsigned
 	if (cluster >= HIP04_MAX_CLUSTERS || cpu >= HIP04_MAX_CPUS_PER_CLUSTER)
 		return -EINVAL;
 
-	spin_lock_irq(&boot_lock);
+	raw_spin_lock_irq(&boot_lock);
 
 	if (hip04_cpu_table[cluster][cpu])
 		goto out;
@@ -147,7 +147,7 @@ static int hip04_boot_secondary(unsigned
 
 out:
 	hip04_cpu_table[cluster][cpu]++;
-	spin_unlock_irq(&boot_lock);
+	raw_spin_unlock_irq(&boot_lock);
 
 	return 0;
 }
@@ -162,11 +162,11 @@ static void hip04_cpu_die(unsigned int l
 	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
 	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
 
-	spin_lock(&boot_lock);
+	raw_spin_lock(&boot_lock);
 	hip04_cpu_table[cluster][cpu]--;
 	if (hip04_cpu_table[cluster][cpu] == 1) {
 		/* A power_up request went ahead of us. */
-		spin_unlock(&boot_lock);
+		raw_spin_unlock(&boot_lock);
 		return;
 	} else if (hip04_cpu_table[cluster][cpu] > 1) {
 		pr_err("Cluster %d CPU%d boots multiple times\n", cluster, cpu);
@@ -174,7 +174,7 @@ static void hip04_cpu_die(unsigned int l
 	}
 
 	last_man = hip04_cluster_is_down(cluster);
-	spin_unlock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 	if (last_man) {
 		/* Since it's Cortex A15, disable L2 prefetching. */
 		asm volatile(
@@ -203,7 +203,7 @@ static int hip04_cpu_kill(unsigned int l
 	       cpu >= HIP04_MAX_CPUS_PER_CLUSTER);
 
 	count = TIMEOUT_MSEC / POLL_MSEC;
-	spin_lock_irq(&boot_lock);
+	raw_spin_lock_irq(&boot_lock);
 	for (tries = 0; tries < count; tries++) {
 		if (hip04_cpu_table[cluster][cpu])
 			goto err;
@@ -211,10 +211,10 @@ static int hip04_cpu_kill(unsigned int l
 		data = readl_relaxed(sysctrl + SC_CPU_RESET_STATUS(cluster));
 		if (data & CORE_WFI_STATUS(cpu))
 			break;
-		spin_unlock_irq(&boot_lock);
+		raw_spin_unlock_irq(&boot_lock);
 		/* Wait for clean L2 when the whole cluster is down. */
 		msleep(POLL_MSEC);
-		spin_lock_irq(&boot_lock);
+		raw_spin_lock_irq(&boot_lock);
 	}
 	if (tries >= count)
 		goto err;
@@ -231,10 +231,10 @@ static int hip04_cpu_kill(unsigned int l
 		goto err;
 	if (hip04_cluster_is_down(cluster))
 		hip04_set_snoop_filter(cluster, 0);
-	spin_unlock_irq(&boot_lock);
+	raw_spin_unlock_irq(&boot_lock);
 	return 1;
 err:
-	spin_unlock_irq(&boot_lock);
+	raw_spin_unlock_irq(&boot_lock);
 	return 0;
 }
 #endif
--- a/arch/arm/mach-omap2/omap-smp.c
+++ b/arch/arm/mach-omap2/omap-smp.c
@@ -69,7 +69,7 @@ static const struct omap_smp_config omap
 	.startup_addr = omap5_secondary_startup,
 };
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 void __iomem *omap4_get_scu_base(void)
 {
@@ -136,8 +136,8 @@ static void omap4_secondary_init(unsigne
 	/*
 	 * Synchronise with the boot thread.
 	 */
-	spin_lock(&boot_lock);
-	spin_unlock(&boot_lock);
+	raw_spin_lock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 }
 
 static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
@@ -150,7 +150,7 @@ static int omap4_boot_secondary(unsigned
 	 * Set synchronisation state between this boot processor
 	 * and the secondary one
 	 */
-	spin_lock(&boot_lock);
+	raw_spin_lock(&boot_lock);
 
 	/*
 	 * Update the AuxCoreBoot0 with boot state for secondary core.
@@ -229,7 +229,7 @@ static int omap4_boot_secondary(unsigned
 	 * Now the secondary core is starting up let it run its
 	 * calibrations, then wait for it to finish
 	 */
-	spin_unlock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 
 	return 0;
 }
--- a/arch/arm/mach-prima2/platsmp.c
+++ b/arch/arm/mach-prima2/platsmp.c
@@ -22,7 +22,7 @@
 
 static void __iomem *clk_base;
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 static void sirfsoc_secondary_init(unsigned int cpu)
 {
@@ -36,8 +36,8 @@ static void sirfsoc_secondary_init(unsig
 	/*
 	 * Synchronise with the boot thread.
 	 */
-	spin_lock(&boot_lock);
-	spin_unlock(&boot_lock);
+	raw_spin_lock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 }
 
 static const struct of_device_id clk_ids[]  = {
@@ -75,7 +75,7 @@ static int sirfsoc_boot_secondary(unsign
 	/* make sure write buffer is drained */
 	mb();
 
-	spin_lock(&boot_lock);
+	raw_spin_lock(&boot_lock);
 
 	/*
 	 * The secondary processor is waiting to be released from
@@ -107,7 +107,7 @@ static int sirfsoc_boot_secondary(unsign
 	 * now the secondary core is starting up let it run its
 	 * calibrations, then wait for it to finish
 	 */
-	spin_unlock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 
 	return pen_release != -1 ? -ENOSYS : 0;
 }
--- a/arch/arm/mach-qcom/platsmp.c
+++ b/arch/arm/mach-qcom/platsmp.c
@@ -46,7 +46,7 @@
 
 extern void secondary_startup_arm(void);
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 #ifdef CONFIG_HOTPLUG_CPU
 static void qcom_cpu_die(unsigned int cpu)
@@ -60,8 +60,8 @@ static void qcom_secondary_init(unsigned
 	/*
 	 * Synchronise with the boot thread.
 	 */
-	spin_lock(&boot_lock);
-	spin_unlock(&boot_lock);
+	raw_spin_lock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 }
 
 static int scss_release_secondary(unsigned int cpu)
@@ -284,7 +284,7 @@ static int qcom_boot_secondary(unsigned
 	 * set synchronisation state between this boot processor
 	 * and the secondary one
 	 */
-	spin_lock(&boot_lock);
+	raw_spin_lock(&boot_lock);
 
 	/*
 	 * Send the secondary CPU a soft interrupt, thereby causing
@@ -297,7 +297,7 @@ static int qcom_boot_secondary(unsigned
 	 * now the secondary core is starting up let it run its
 	 * calibrations, then wait for it to finish
 	 */
-	spin_unlock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 
 	return ret;
 }
--- a/arch/arm/mach-spear/platsmp.c
+++ b/arch/arm/mach-spear/platsmp.c
@@ -32,7 +32,7 @@ static void write_pen_release(int val)
 	sync_cache_w(&pen_release);
 }
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 static void __iomem *scu_base = IOMEM(VA_SCU_BASE);
 
@@ -47,8 +47,8 @@ static void spear13xx_secondary_init(uns
 	/*
 	 * Synchronise with the boot thread.
 	 */
-	spin_lock(&boot_lock);
-	spin_unlock(&boot_lock);
+	raw_spin_lock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 }
 
 static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle)
@@ -59,7 +59,7 @@ static int spear13xx_boot_secondary(unsi
 	 * set synchronisation state between this boot processor
 	 * and the secondary one
 	 */
-	spin_lock(&boot_lock);
+	raw_spin_lock(&boot_lock);
 
 	/*
 	 * The secondary processor is waiting to be released from
@@ -84,7 +84,7 @@ static int spear13xx_boot_secondary(unsi
 	 * now the secondary core is starting up let it run its
 	 * calibrations, then wait for it to finish
 	 */
-	spin_unlock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 
 	return pen_release != -1 ? -ENOSYS : 0;
 }
--- a/arch/arm/mach-sti/platsmp.c
+++ b/arch/arm/mach-sti/platsmp.c
@@ -35,7 +35,7 @@ static void write_pen_release(int val)
 	sync_cache_w(&pen_release);
 }
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 static void sti_secondary_init(unsigned int cpu)
 {
@@ -48,8 +48,8 @@ static void sti_secondary_init(unsigned
 	/*
 	 * Synchronise with the boot thread.
 	 */
-	spin_lock(&boot_lock);
-	spin_unlock(&boot_lock);
+	raw_spin_lock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 }
 
 static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle)
@@ -60,7 +60,7 @@ static int sti_boot_secondary(unsigned i
 	 * set synchronisation state between this boot processor
 	 * and the secondary one
 	 */
-	spin_lock(&boot_lock);
+	raw_spin_lock(&boot_lock);
 
 	/*
 	 * The secondary processor is waiting to be released from
@@ -91,7 +91,7 @@ static int sti_boot_secondary(unsigned i
 	 * now the secondary core is starting up let it run its
 	 * calibrations, then wait for it to finish
 	 */
-	spin_unlock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 
 	return pen_release != -1 ? -ENOSYS : 0;
 }
--- a/arch/arm/mach-sunxi/mc_smp.c
+++ b/arch/arm/mach-sunxi/mc_smp.c
@@ -369,7 +369,7 @@ static void __naked sunxi_mc_smp_seconda
 	);
 }
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 static bool sunxi_mc_smp_cluster_is_down(unsigned int cluster)
 {
@@ -401,7 +401,7 @@ static int sunxi_mc_smp_boot_secondary(u
 	if (cluster >= SUNXI_NR_CLUSTERS || cpu >= SUNXI_CPUS_PER_CLUSTER)
 		return -EINVAL;
 
-	spin_lock_irq(&boot_lock);
+	raw_spin_lock_irq(&boot_lock);
 
 	if (sunxi_mc_smp_cpu_table[cluster][cpu])
 		goto out;
@@ -419,7 +419,7 @@ static int sunxi_mc_smp_boot_secondary(u
 
 out:
 	sunxi_mc_smp_cpu_table[cluster][cpu]++;
-	spin_unlock_irq(&boot_lock);
+	raw_spin_unlock_irq(&boot_lock);
 
 	return 0;
 }
@@ -450,13 +450,13 @@ static void sunxi_mc_smp_cpu_die(unsigne
 	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
 	pr_debug("%s: cluster %u cpu %u\n", __func__, cluster, cpu);
 
-	spin_lock(&boot_lock);
+	raw_spin_lock(&boot_lock);
 	sunxi_mc_smp_cpu_table[cluster][cpu]--;
 	if (sunxi_mc_smp_cpu_table[cluster][cpu] == 1) {
 		/* A power_up request went ahead of us. */
 		pr_debug("%s: aborting due to a power up request\n",
 			 __func__);
-		spin_unlock(&boot_lock);
+		raw_spin_unlock(&boot_lock);
 		return;
 	} else if (sunxi_mc_smp_cpu_table[cluster][cpu] > 1) {
 		pr_err("Cluster %d CPU%d boots multiple times\n",
@@ -465,7 +465,7 @@ static void sunxi_mc_smp_cpu_die(unsigne
 	}
 
 	last_man = sunxi_mc_smp_cluster_is_down(cluster);
-	spin_unlock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 
 	gic_cpu_if_down(0);
 	if (last_man)
@@ -541,11 +541,11 @@ static int sunxi_mc_smp_cpu_kill(unsigne
 
 	/* wait for CPU core to die and enter WFI */
 	count = TIMEOUT_USEC / POLL_USEC;
-	spin_lock_irq(&boot_lock);
+	raw_spin_lock_irq(&boot_lock);
 	for (tries = 0; tries < count; tries++) {
-		spin_unlock_irq(&boot_lock);
+		raw_spin_unlock_irq(&boot_lock);
 		usleep_range(POLL_USEC / 2, POLL_USEC);
-		spin_lock_irq(&boot_lock);
+		raw_spin_lock_irq(&boot_lock);
 
 		/*
 		 * If the user turns off a bunch of cores@the same
@@ -592,7 +592,7 @@ static int sunxi_mc_smp_cpu_kill(unsigne
 	sunxi_cluster_powerdown(cluster);
 
 out:
-	spin_unlock_irq(&boot_lock);
+	raw_spin_unlock_irq(&boot_lock);
 	pr_debug("%s: cluster %u cpu %u powerdown: %d\n",
 		 __func__, cluster, cpu, ret);
 	return !ret;
--- a/arch/arm/plat-versatile/platsmp.c
+++ b/arch/arm/plat-versatile/platsmp.c
@@ -32,7 +32,7 @@ static void write_pen_release(int val)
 	sync_cache_w(&pen_release);
 }
 
-static DEFINE_SPINLOCK(boot_lock);
+static DEFINE_RAW_SPINLOCK(boot_lock);
 
 void versatile_secondary_init(unsigned int cpu)
 {
@@ -45,8 +45,8 @@ void versatile_secondary_init(unsigned i
 	/*
 	 * Synchronise with the boot thread.
 	 */
-	spin_lock(&boot_lock);
-	spin_unlock(&boot_lock);
+	raw_spin_lock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 }
 
 int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle)
@@ -57,7 +57,7 @@ int versatile_boot_secondary(unsigned in
 	 * Set synchronisation state between this boot processor
 	 * and the secondary one
 	 */
-	spin_lock(&boot_lock);
+	raw_spin_lock(&boot_lock);
 
 	/*
 	 * This is really belt and braces; we hold unintended secondary
@@ -87,7 +87,7 @@ int versatile_boot_secondary(unsigned in
 	 * now the secondary core is starting up let it run its
 	 * calibrations, then wait for it to finish
 	 */
-	spin_unlock(&boot_lock);
+	raw_spin_unlock(&boot_lock);
 
 	return pen_release != -1 ? -ENOSYS : 0;
 }

[PATCH] arm: kprobe: replace patch_lock to raw lock

[Sebastian Andrzej Siewior]

From: Yang Shi <yang.shi@linaro.org>

When running kprobe on -rt kernel, the below bug is caught:

BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:931
in_atomic(): 1, irqs_disabled(): 128, pid: 14, name: migration/0
INFO: lockdep is turned off.
irq event stamp: 238
hardirqs last enabled at (237): [<80b5aecc>] _raw_spin_unlock_irqrestore+0x88/0x90
hardirqs last disabled at (238): [<80b56d88>] __schedule+0xec/0x94c
softirqs last enabled at (0): [<80225584>] copy_process.part.5+0x30c/0x1994
softirqs last disabled at (0): [< (null)>] (null)
Preemption disabled at:[<802f2b98>] cpu_stopper_thread+0xc0/0x140

CPU: 0 PID: 14 Comm: migration/0 Tainted: G O 4.8.3-rt2 #1
Hardware name: Freescale LS1021A
[<80212e7c>] (unwind_backtrace) from [<8020cd2c>] (show_stack+0x20/0x24)
[<8020cd2c>] (show_stack) from [<80689e14>] (dump_stack+0xa0/0xcc)
[<80689e14>] (dump_stack) from [<8025a43c>] (___might_sleep+0x1b8/0x2a4)
[<8025a43c>] (___might_sleep) from [<80b5b324>] (rt_spin_lock+0x34/0x74)
[<80b5b324>] (rt_spin_lock) from [<80b5c31c>] (__patch_text_real+0x70/0xe8)
[<80b5c31c>] (__patch_text_real) from [<80b5c3ac>] (patch_text_stop_machine+0x18/0x20)
[<80b5c3ac>] (patch_text_stop_machine) from [<802f2920>] (multi_cpu_stop+0xfc/0x134)
[<802f2920>] (multi_cpu_stop) from [<802f2ba0>] (cpu_stopper_thread+0xc8/0x140)
[<802f2ba0>] (cpu_stopper_thread) from [<802563a4>] (smpboot_thread_fn+0x1a4/0x354)
[<802563a4>] (smpboot_thread_fn) from [<80251d38>] (kthread+0x104/0x11c)
[<80251d38>] (kthread) from [<80207f70>] (ret_from_fork+0x14/0x24)

Since patch_text_stop_machine() is called in stop_machine() which disables IRQ,
sleepable lock should be not used in this atomic context, so replace patch_lock
to raw lock.

Cc: Russell King <linux@armlinux.org.uk> 
Signed-off-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 arch/arm/kernel/patch.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/arch/arm/kernel/patch.c
+++ b/arch/arm/kernel/patch.c
@@ -16,7 +16,7 @@ struct patch {
 	unsigned int insn;
 };
 
-static DEFINE_SPINLOCK(patch_lock);
+static DEFINE_RAW_SPINLOCK(patch_lock);
 
 static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags)
 	__acquires(&patch_lock)
@@ -33,7 +33,7 @@ static void __kprobes *patch_map(void *a
 		return addr;
 
 	if (flags)
-		spin_lock_irqsave(&patch_lock, *flags);
+		raw_spin_lock_irqsave(&patch_lock, *flags);
 	else
 		__acquire(&patch_lock);
 
@@ -48,7 +48,7 @@ static void __kprobes patch_unmap(int fi
 	clear_fixmap(fixmap);
 
 	if (flags)
-		spin_unlock_irqrestore(&patch_lock, *flags);
+		raw_spin_unlock_irqrestore(&patch_lock, *flags);
 	else
 		__release(&patch_lock);
 }