Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1595499 > unrolled thread

[PATCH RT 0/8] Linux 3.18.48-rt54-rc1

Back to article view | Back to linux.kernel

Contents

  [PATCH RT 0/8] Linux 3.18.48-rt54-rc1 Steven Rostedt <rostedt@goodmis.org> - 2017-03-08 21:40 +0100
    [PATCH RT 5/8] lockdep: Handle statically initialized PER_CPU locks proper Steven Rostedt <rostedt@goodmis.org> - 2017-03-08 21:40 +0100
    [PATCH RT 8/8] Linux 3.18.48-rt54-rc1 Steven Rostedt <rostedt@goodmis.org> - 2017-03-08 21:40 +0100
    [PATCH RT 7/8] lockdep: Fix compilation error for !CONFIG_MODULES and !CONFIG_SMP Steven Rostedt <rostedt@goodmis.org> - 2017-03-08 21:40 +0100

#1595499 — [PATCH RT 0/8] Linux 3.18.48-rt54-rc1

Dear RT Folks,

This is the RT stable review cycle of patch 3.18.48-rt54-rc1.

Please scream at me if I messed something up. Please test the patches too.

The -rc release will be uploaded to kernel.org and will be deleted when
the final release is out. This is just a review release (or release candidate).

The pre-releases will not be pushed to the git repository, only the
final release is.

If all goes well, this patch will be converted to the next main release
on 3/10/2017.

Enjoy,

-- Steve


To build 3.18.48-rt54-rc1 directly, the following patches should be applied:

  http://www.kernel.org/pub/linux/kernel/v3.x/linux-3.18.tar.xz

  http://www.kernel.org/pub/linux/kernel/v3.x/patch-3.18.48.xz

  http://www.kernel.org/pub/linux/kernel/projects/rt/3.18/patch-3.18.48-rt54-rc1.patch.xz

You can also build from 3.18.48-rt53 by applying the incremental patch:

http://www.kernel.org/pub/linux/kernel/projects/rt/3.18/incr/patch-3.18.48-rt53-rt54-rc1.patch.xz


Changes from 3.18.48-rt53:

---


Dan Murphy (1):
      lockdep: Fix compilation error for !CONFIG_MODULES and !CONFIG_SMP

John Ogness (1):
      x86/mm/cpa: avoid wbinvd() for PREEMPT

Julia Cartwright (1):
      pinctrl: qcom: Use raw spinlock variants

Sebastian Andrzej Siewior (3):
      radix-tree: use local locks
      rt: Drop mutex_disable() on !DEBUG configs and the GPL suffix from export symbol
      rt: Drop the removal of _GPL from rt_mutex_destroy()'s EXPORT_SYMBOL

Steven Rostedt (VMware) (1):
      Linux 3.18.48-rt54-rc1

Thomas Gleixner (1):
      lockdep: Handle statically initialized PER_CPU locks proper

----
 arch/x86/mm/pageattr.c             |  8 +++++++
 drivers/pinctrl/qcom/pinctrl-msm.c | 48 +++++++++++++++++++-------------------
 include/linux/module.h             |  6 +++++
 include/linux/mutex_rt.h           |  5 ++++
 include/linux/percpu.h             |  1 +
 include/linux/radix-tree.h         | 12 ++--------
 kernel/locking/lockdep.c           | 32 ++++++++++++++++++-------
 kernel/module.c                    | 36 ++++++++++++++++++----------
 lib/radix-tree.c                   | 23 +++++++++++-------
 localversion-rt                    |  2 +-
 mm/percpu.c                        | 37 ++++++++++++++++++-----------
 11 files changed, 131 insertions(+), 79 deletions(-)

[toc] | [next] | [standalone]

#1595507 — [PATCH RT 5/8] lockdep: Handle statically initialized PER_CPU locks proper

3.18.48-rt54-rc1 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Thomas Gleixner <tglx@linutronix.de>

If a PER_CPU struct which contains a spin_lock is statically initialized
via:

DEFINE_PER_CPU(struct foo, bla) = {
	.lock = __SPIN_LOCK_UNLOCKED(bla.lock)
};

then lockdep assigns a seperate key to each lock because the logic for
assigning a key to statically initialized locks is to use the address as
the key. With per CPU locks the address is obvioulsy different on each CPU.

That's wrong, because all locks should have the same key.

To solve this the following modifications are required:

 1) Extend the is_kernel/module_percpu_addr() functions to hand back the
    canonical address of the per CPU address, i.e. the per CPU address
    minus the per CPU offset.

 2) Check the lock address with these functions and if the per CPU check
    matches use the returned canonical address as the lock key, so all per
    CPU locks have the same key.

 3) Move the static_obj(key) check into look_up_lock_class() so this check
    can be avoided for statically initialized per CPU locks.  That's
    required because the canonical address fails the static_obj(key) check
    for obvious reasons.

Reported-by: Mike Galbraith <efault@gmx.de>
Cc: stable-rt@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 include/linux/module.h   |  1 +
 include/linux/percpu.h   |  1 +
 kernel/locking/lockdep.c | 32 +++++++++++++++++++++++---------
 kernel/module.c          | 31 +++++++++++++++++++------------
 mm/percpu.c              | 37 +++++++++++++++++++++++--------------
 5 files changed, 67 insertions(+), 35 deletions(-)

diff --git a/include/linux/module.h b/include/linux/module.h
index 6fc269ce701c..9ec8a28c65bb 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -394,6 +394,7 @@ static inline int module_is_live(struct module *mod)
 struct module *__module_text_address(unsigned long addr);
 struct module *__module_address(unsigned long addr);
 bool is_module_address(unsigned long addr);
+bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr);
 bool is_module_percpu_address(unsigned long addr);
 bool is_module_text_address(unsigned long addr);
 
diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 208d86d80cba..a3a446c2901b 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -144,6 +144,7 @@ extern int __init pcpu_page_first_chunk(size_t reserved_size,
 #endif
 
 extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
+extern bool __is_kernel_percpu_address(unsigned long addr, unsigned long *can_addr);
 extern bool is_kernel_percpu_address(unsigned long addr);
 
 #if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index fce6f6f69aad..d4a4d8ea55d6 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -654,6 +654,7 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)
 	struct lockdep_subclass_key *key;
 	struct list_head *hash_head;
 	struct lock_class *class;
+	bool is_static = false;
 
 #ifdef CONFIG_DEBUG_LOCKDEP
 	/*
@@ -681,10 +682,23 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)
 
 	/*
 	 * Static locks do not have their class-keys yet - for them the key
-	 * is the lock object itself:
+	 * is the lock object itself. If the lock is in the per cpu area,
+	 * the canonical address of the lock (per cpu offset removed) is
+	 * used.
 	 */
-	if (unlikely(!lock->key))
-		lock->key = (void *)lock;
+	if (unlikely(!lock->key)) {
+		unsigned long can_addr, addr = (unsigned long)lock;
+
+		if (__is_kernel_percpu_address(addr, &can_addr))
+			lock->key = (void *)can_addr;
+		else if (__is_module_percpu_address(addr, &can_addr))
+			lock->key = (void *)can_addr;
+		else if (static_obj(lock))
+			lock->key = (void *)lock;
+		else
+			return ERR_PTR(-EINVAL);
+		is_static = true;
+	}
 
 	/*
 	 * NOTE: the class-key must be unique. For dynamic locks, a static
@@ -714,7 +728,7 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)
 		}
 	}
 
-	return NULL;
+	return is_static || static_obj(lock->key) ? NULL : ERR_PTR(-EINVAL);
 }
 
 /*
@@ -731,13 +745,13 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)
 	unsigned long flags;
 
 	class = look_up_lock_class(lock, subclass);
-	if (likely(class))
+	if (likely(!IS_ERR_OR_NULL(class)))
 		goto out_set_class_cache;
 
 	/*
 	 * Debug-check: all keys must be persistent!
- 	 */
-	if (!static_obj(lock->key)) {
+	 */
+	if (IS_ERR(class)) {
 		debug_locks_off();
 		printk("INFO: trying to register non-static key.\n");
 		printk("the code is fine but needs lockdep annotation.\n");
@@ -3276,7 +3290,7 @@ static int match_held_lock(struct held_lock *hlock, struct lockdep_map *lock)
 		 * Clearly if the lock hasn't been acquired _ever_, we're not
 		 * holding it either, so report failure.
 		 */
-		if (!class)
+		if (IS_ERR_OR_NULL(class))
 			return 0;
 
 		/*
@@ -3938,7 +3952,7 @@ void lockdep_reset_lock(struct lockdep_map *lock)
 		 * If the class exists we look it up and zap it:
 		 */
 		class = look_up_lock_class(lock, j);
-		if (class)
+		if (!IS_ERR_OR_NULL(class))
 			zap_class(class);
 	}
 	/*
diff --git a/kernel/module.c b/kernel/module.c
index 737d53099360..377f52a286a8 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -526,16 +526,7 @@ static void percpu_modcopy(struct module *mod,
 		memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
 }
 
-/**
- * is_module_percpu_address - test whether address is from module static percpu
- * @addr: address to test
- *
- * Test whether @addr belongs to module static percpu area.
- *
- * RETURNS:
- * %true if @addr is from module static percpu area
- */
-bool is_module_percpu_address(unsigned long addr)
+bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
 {
 	struct module *mod;
 	unsigned int cpu;
@@ -549,9 +540,11 @@ bool is_module_percpu_address(unsigned long addr)
 			continue;
 		for_each_possible_cpu(cpu) {
 			void *start = per_cpu_ptr(mod->percpu, cpu);
+			void *va = (void *)addr;
 
-			if ((void *)addr >= start &&
-			    (void *)addr < start + mod->percpu_size) {
+			if (va >= start && va < start + mod->percpu_size) {
+				if (can_addr)
+					*can_addr = (unsigned long) (va - start);
 				preempt_enable();
 				return true;
 			}
@@ -562,6 +555,20 @@ bool is_module_percpu_address(unsigned long addr)
 	return false;
 }
 
+/**
+ * is_module_percpu_address - test whether address is from module static percpu
+ * @addr: address to test
+ *
+ * Test whether @addr belongs to module static percpu area.
+ *
+ * RETURNS:
+ * %true if @addr is from module static percpu area
+ */
+bool is_module_percpu_address(unsigned long addr)
+{
+	return __is_module_percpu_address(addr, NULL);
+}
+
 #else /* ... !CONFIG_SMP */
 
 static inline void __percpu *mod_percpu(struct module *mod)
diff --git a/mm/percpu.c b/mm/percpu.c
index 5ae6e0284967..d270e8077f52 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -1282,18 +1282,7 @@ void free_percpu(void __percpu *ptr)
 }
 EXPORT_SYMBOL_GPL(free_percpu);
 
-/**
- * is_kernel_percpu_address - test whether address is from static percpu area
- * @addr: address to test
- *
- * Test whether @addr belongs to in-kernel static percpu area.  Module
- * static percpu areas are not considered.  For those, use
- * is_module_percpu_address().
- *
- * RETURNS:
- * %true if @addr is from in-kernel static percpu area, %false otherwise.
- */
-bool is_kernel_percpu_address(unsigned long addr)
+bool __is_kernel_percpu_address(unsigned long addr, unsigned long *can_addr)
 {
 #ifdef CONFIG_SMP
 	const size_t static_size = __per_cpu_end - __per_cpu_start;
@@ -1302,16 +1291,36 @@ bool is_kernel_percpu_address(unsigned long addr)
 
 	for_each_possible_cpu(cpu) {
 		void *start = per_cpu_ptr(base, cpu);
+		void *va = (void *)addr;
 
-		if ((void *)addr >= start && (void *)addr < start + static_size)
+		if (va >= start && va < start + static_size) {
+			if (can_addr)
+				*can_addr = (unsigned long) (va - start);
 			return true;
-        }
+		}
+	}
 #endif
 	/* on UP, can't distinguish from other static vars, always false */
 	return false;
 }
 
 /**
+ * is_kernel_percpu_address - test whether address is from static percpu area
+ * @addr: address to test
+ *
+ * Test whether @addr belongs to in-kernel static percpu area.  Module
+ * static percpu areas are not considered.  For those, use
+ * is_module_percpu_address().
+ *
+ * RETURNS:
+ * %true if @addr is from in-kernel static percpu area, %false otherwise.
+ */
+bool is_kernel_percpu_address(unsigned long addr)
+{
+	return __is_kernel_percpu_address(addr, NULL);
+}
+
+/**
  * per_cpu_ptr_to_phys - convert translated percpu address to physical address
  * @addr: the address to be converted to physical address
  *
-- 
2.10.2

[toc] | [prev] | [next] | [standalone]

#1595509 — [PATCH RT 8/8] Linux 3.18.48-rt54-rc1

3.18.48-rt54-rc1 stable review patch.
If anyone has any objections, please let me know.

------------------

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

---
 localversion-rt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/localversion-rt b/localversion-rt
index e6c0dc6a54cd..cc1bfc08848a 100644
--- a/localversion-rt
+++ b/localversion-rt
@@ -1 +1 @@
--rt53
+-rt54-rc1
-- 
2.10.2

[toc] | [prev] | [next] | [standalone]

#1595510 — [PATCH RT 7/8] lockdep: Fix compilation error for !CONFIG_MODULES and !CONFIG_SMP

3.18.48-rt54-rc1 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Dan Murphy <dmurphy@ti.com>

When CONFIG_MODULES is not set then it fails to compile in lockdep:

|kernel/locking/lockdep.c: In function 'look_up_lock_class':
|kernel/locking/lockdep.c:684:12: error: implicit declaration of function
| '__is_module_percpu_address' [-Werror=implicit-function-declaration]

If CONFIG_MODULES is set but CONFIG_SMP is not, then it compiles but
fails link at the end:

|kernel/locking/lockdep.c:684: undefined reference to `__is_module_percpu_address'
|kernel/built-in.o:(.debug_addr+0x1e674): undefined reference to `__is_module_percpu_address'

This patch adds the function for both cases.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
[bigeasy: merge the two patches from Dan into one, adapt changelog]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 include/linux/module.h | 5 +++++
 kernel/module.c        | 5 +++++
 2 files changed, 10 insertions(+)

diff --git a/include/linux/module.h b/include/linux/module.h
index 9ec8a28c65bb..208518a81281 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -547,6 +547,11 @@ static inline bool is_module_percpu_address(unsigned long addr)
 	return false;
 }
 
+static inline bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
+{
+	return false;
+}
+
 static inline bool is_module_text_address(unsigned long addr)
 {
 	return false;
diff --git a/kernel/module.c b/kernel/module.c
index 377f52a286a8..ab5169e72289 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -600,6 +600,11 @@ bool is_module_percpu_address(unsigned long addr)
 	return false;
 }
 
+bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
+{
+	return false;
+}
+
 #endif /* CONFIG_SMP */
 
 #define MODINFO_ATTR(field)	\
-- 
2.10.2

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web