include/linux/cleanup.h | 41 +++++++++++++++++++++++++++++++++-------- 1 file changed, 33 insertions(+), 8 deletions(-)
Change scoped_guard() and scoped_cond_guard() macros to make reasoning
about them easier for static analysis tools (smatch, compiler
diagnostics), especially to enable them to tell if the given usage of
scoped_guard() is with a conditional lock class (interruptible-locks,
try-locks) or not (like simple mutex_lock()).
Add compile-time error if scoped_cond_guard() is used for non-conditional
lock class.
Beyond easier tooling and a little shrink reported by bloat-o-meter
this patch enables developer to write code like:
int foo(struct my_drv *adapter)
{
scoped_guard(spinlock, &adapter->some_spinlock)
return adapter->spinlock_protected_var;
}
Current scoped_guard() implementation does not support that,
due to compiler complaining:
error: control reaches end of non-void function [-Werror=return-type]
Technical stuff about the change:
scoped_guard() macro uses common idiom of using "for" statement to declare
a scoped variable. Unfortunately, current logic is too hard for compiler
diagnostics to be sure that there is exactly one loop step; fix that.
To make any loop so trivial that there is no above warning, it must not
depend on any non-const variable to tell if there are more steps. There is
no obvious solution for that in C, but one could use the compound
statement expression with "goto" jumping past the "loop", effectively
leaving only the subscope part of the loop semantics.
More impl details:
one more level of macro indirection is now needed to avoid duplicating
label names;
I didn't spot any other place that is using the
"for (...; goto label) if (0) label: break;" idiom, so it's not packed for
reuse beyond scoped_guard() family, what makes actual macros code cleaner.
There was also a need to introduce const true/false variable per lock
class, it is used to aid compiler diagnostics reasoning about "exactly
1 step" loops (note that converting that to function would undo the whole
benefit).
Big thanks to Andy Shevchenko for help on this patch, both internal and
public, ranging from whitespace/formatting, through commit message
clarifications, general improvements, ending with presenting alternative
approaches - all despite not even liking the idea.
Big thanks to Dmitry Torokhov for the idea of compile-time check for
scoped_cond_guard(), and general improvements for the patch.
Big thanks to David Lechner for idea to cover also scoped_cond_guard().
CC: David Lechner <dlechner@baylibre.com>
CC: Dan Carpenter <dan.carpenter@linaro.org>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Andy Shevchenko <andriy.shevchenko@intel.com>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
---
PATCH v3:
cover also scoped_cond_guard() to be able to return from them (David Lechner);
capitalize comment (Andy)
PATCH v2:
drop Andy's NACK,
(the reasons for NACK were in RFC v1; Peter backed up my idea for this
patch in PATCH v1 discussion, and Andy withdrawn the NACK);
whitespace/formatting/style issues - Andy;
additional code comments - Dmitry.
https://lore.kernel.org/netdev/20241009114446.14873-1-przemyslaw.kitszel@intel.com
PATCH v1:
changes thanks to Dmitry Torokhov:
better writeup in commit msg;
"__" prefix added to internal macros;
reorder "if (0)-else" and "for" to avoid goto jumping back;
compile-time check for scoped_cond_guard()
https://lore.kernel.org/netdev/20241003113906.750116-1-przemyslaw.kitszel@intel.com
RFC v2:
https://lore.kernel.org/netdev/20241001145718.8962-1-przemyslaw.kitszel@intel.com
remove ", 1" condition, as scoped_guard() could be used also for
conditional locks (try-lock, irq-lock, etc) - this was pointed out by
Dmitry Torokhov and Dan Carpenter;
reorder macros to have them defined prior to use - Markus Elfring.
RFC v1:
https://lore.kernel.org/netdev/20240926134347.19371-1-przemyslaw.kitszel@intel.com
---
include/linux/cleanup.h | 41 +++++++++++++++++++++++++++++++++--------
1 file changed, 33 insertions(+), 8 deletions(-)
diff --git a/include/linux/cleanup.h b/include/linux/cleanup.h
index a3d3e888cf1f..6069dd6237df 100644
--- a/include/linux/cleanup.h
+++ b/include/linux/cleanup.h
@@ -149,14 +149,21 @@ static inline class_##_name##_t class_##_name##ext##_constructor(_init_args) \
* similar to scoped_guard(), except it does fail when the lock
* acquire fails.
*
+ * Only for conditional locks.
+ *
*/
+#define __DEFINE_CLASS_IS_CONDITIONAL(_name, _is_cond) \
+static __maybe_unused const bool class_##_name##_is_conditional = _is_cond
+
#define DEFINE_GUARD(_name, _type, _lock, _unlock) \
+ __DEFINE_CLASS_IS_CONDITIONAL(_name, false); \
DEFINE_CLASS(_name, _type, if (_T) { _unlock; }, ({ _lock; _T; }), _type _T); \
static inline void * class_##_name##_lock_ptr(class_##_name##_t *_T) \
{ return *_T; }
#define DEFINE_GUARD_COND(_name, _ext, _condlock) \
+ __DEFINE_CLASS_IS_CONDITIONAL(_name##_ext, true); \
EXTEND_CLASS(_name, _ext, \
({ void *_t = _T; if (_T && !(_condlock)) _t = NULL; _t; }), \
class_##_name##_t _T) \
@@ -167,17 +174,32 @@ static inline class_##_name##_t class_##_name##ext##_constructor(_init_args) \
CLASS(_name, __UNIQUE_ID(guard))
#define __guard_ptr(_name) class_##_name##_lock_ptr
+#define __is_cond_ptr(_name) class_##_name##_is_conditional
-#define scoped_guard(_name, args...) \
- for (CLASS(_name, scope)(args), \
- *done = NULL; __guard_ptr(_name)(&scope) && !done; done = (void *)1)
+/*
+ * Helper macro for scoped_guard() and scoped_cond_guard().
+ *
+ * Note that the "__is_cond_ptr(_name)" part of the condition ensures that
+ * compiler would be sure that for the unconditional locks the body of the
+ * loop (caller-provided code glued to the else clause) could not be skipped.
+ * It is needed because the other part - "__guard_ptr(_name)(&scope)" - is too
+ * hard to deduce (even if could be proven true for unconditional locks).
+ */
+#define __scoped_guard(_name, _fail, _label, args...) \
+ for (CLASS(_name, scope)(args); true; ({ goto _label; })) \
+ if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
+ _fail; \
+_label: \
+ break; \
+ } else
-#define scoped_cond_guard(_name, _fail, args...) \
- for (CLASS(_name, scope)(args), \
- *done = NULL; !done; done = (void *)1) \
- if (!__guard_ptr(_name)(&scope)) _fail; \
- else
+#define scoped_guard(_name, args...) \
+ __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
+#define scoped_cond_guard(_name, _fail, args...) \
+ __scoped_guard(_name, \
+ BUILD_BUG_ON(!__is_cond_ptr(_name)); _fail, \
+ __UNIQUE_ID(label), args)
/*
* Additional helper macros for generating lock guards with types, either for
* locks that don't have a native type (eg. RCU, preempt) or those that need a
@@ -233,14 +255,17 @@ static inline class_##_name##_t class_##_name##_constructor(void) \
}
#define DEFINE_LOCK_GUARD_1(_name, _type, _lock, _unlock, ...) \
+__DEFINE_CLASS_IS_CONDITIONAL(_name, false); \
__DEFINE_UNLOCK_GUARD(_name, _type, _unlock, __VA_ARGS__) \
__DEFINE_LOCK_GUARD_1(_name, _type, _lock)
#define DEFINE_LOCK_GUARD_0(_name, _lock, _unlock, ...) \
+__DEFINE_CLASS_IS_CONDITIONAL(_name, false); \
__DEFINE_UNLOCK_GUARD(_name, void, _unlock, __VA_ARGS__) \
__DEFINE_LOCK_GUARD_0(_name, _lock)
#define DEFINE_LOCK_GUARD_1_COND(_name, _ext, _condlock) \
+ __DEFINE_CLASS_IS_CONDITIONAL(_name##_ext, true); \
EXTEND_CLASS(_name, _ext, \
({ class_##_name##_t _t = { .lock = l }, *_T = &_t;\
if (_T->lock && !(_condlock)) _T->lock = NULL; \
base-commit: 44badc908f2c85711cb18e45e13119c10ad3a05f
--
2.46.0Hi Przemek,
kernel test robot noticed the following build warnings:
[auto build test WARNING on 44badc908f2c85711cb18e45e13119c10ad3a05f]
url: https://github.com/intel-lab-lkp/linux/commits/Przemek-Kitszel/cleanup-adjust-scoped_guard-macros-to-avoid-potential-warning/20241011-201702
base: 44badc908f2c85711cb18e45e13119c10ad3a05f
patch link: https://lore.kernel.org/r/20241011121535.28049-1-przemyslaw.kitszel%40intel.com
patch subject: [PATCH v3] cleanup: adjust scoped_guard() macros to avoid potential warning
config: hexagon-randconfig-001-20241013 (https://download.01.org/0day-ci/archive/20241013/202410131247.7EWZ1WLP-lkp@intel.com/config)
compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 70e0a7e7e6a8541bcc46908c592eed561850e416)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241013/202410131247.7EWZ1WLP-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202410131247.7EWZ1WLP-lkp@intel.com/
All warnings (new ones prefixed by >>):
In file included from sound/core/pcm_native.c:8:
In file included from include/linux/mm.h:2213:
include/linux/vmstat.h:518:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
518 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
| ~~~~~~~~~~~ ^ ~~~
In file included from sound/core/pcm_native.c:15:
In file included from include/linux/io.h:14:
In file included from arch/hexagon/include/asm/io.h:328:
include/asm-generic/io.h:548:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
548 | val = __raw_readb(PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:561:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
561 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu'
37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
| ^
In file included from sound/core/pcm_native.c:15:
In file included from include/linux/io.h:14:
In file included from arch/hexagon/include/asm/io.h:328:
include/asm-generic/io.h:574:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
574 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu'
35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
| ^
In file included from sound/core/pcm_native.c:15:
In file included from include/linux/io.h:14:
In file included from arch/hexagon/include/asm/io.h:328:
include/asm-generic/io.h:585:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
585 | __raw_writeb(value, PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:595:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
595 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:605:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
605 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
>> sound/core/pcm_native.c:2277:2: warning: variable 'target_group' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
2277 | scoped_guard(pcm_stream_lock_irq, substream) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sound/core/pcm_native.c:2285:25: note: uninitialized use occurs here
2285 | snd_pcm_group_lock_irq(target_group, nonatomic);
| ^~~~~~~~~~~~
sound/core/pcm_native.c:2277:2: note: remove the 'if' if its condition is always false
2277 | scoped_guard(pcm_stream_lock_irq, substream) {
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
sound/core/pcm_native.c:2249:36: note: initialize the variable 'target_group' to silence this warning
2249 | struct snd_pcm_group *target_group;
| ^
| = NULL
>> sound/core/pcm_native.c:2993:2: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
2993 | scoped_guard(pcm_stream_lock_irq, substream) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sound/core/pcm_native.c:3001:9: note: uninitialized use occurs here
3001 | return ret;
| ^~~
sound/core/pcm_native.c:2993:2: note: remove the 'if' if its condition is always false
2993 | scoped_guard(pcm_stream_lock_irq, substream) {
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
sound/core/pcm_native.c:2988:23: note: initialize the variable 'ret' to silence this warning
2988 | snd_pcm_sframes_t ret;
| ^
| = 0
sound/core/pcm_native.c:3012:2: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
3012 | scoped_guard(pcm_stream_lock_irq, substream) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sound/core/pcm_native.c:3020:9: note: uninitialized use occurs here
3020 | return ret;
| ^~~
sound/core/pcm_native.c:3012:2: note: remove the 'if' if its condition is always false
3012 | scoped_guard(pcm_stream_lock_irq, substream) {
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
sound/core/pcm_native.c:3007:23: note: initialize the variable 'ret' to silence this warning
3007 | snd_pcm_sframes_t ret;
| ^
| = 0
>> sound/core/pcm_native.c:3028:2: warning: variable 'err' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
3028 | scoped_guard(pcm_stream_lock_irq, substream) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sound/core/pcm_native.c:3035:9: note: uninitialized use occurs here
3035 | return err;
| ^~~
sound/core/pcm_native.c:3028:2: note: remove the 'if' if its condition is always false
3028 | scoped_guard(pcm_stream_lock_irq, substream) {
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
sound/core/pcm_native.c:3026:9: note: initialize the variable 'err' to silence this warning
3026 | int err;
| ^
| = 0
11 warnings generated.
--
>> sound/core/sound.c:152:2: warning: variable 'new_fops' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
152 | scoped_guard(mutex, &sound_mutex) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sound/core/sound.c:161:7: note: uninitialized use occurs here
161 | if (!new_fops)
| ^~~~~~~~
include/linux/compiler.h:55:47: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~
include/linux/compiler.h:57:52: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~
sound/core/sound.c:152:2: note: remove the 'if' if its condition is always false
152 | scoped_guard(mutex, &sound_mutex) {
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
sound/core/sound.c:147:40: note: initialize the variable 'new_fops' to silence this warning
147 | const struct file_operations *new_fops;
| ^
| = NULL
1 warning generated.
--
In file included from drivers/mailbox/arm_mhuv3.c:15:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:14:
In file included from arch/hexagon/include/asm/io.h:328:
include/asm-generic/io.h:548:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
548 | val = __raw_readb(PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:561:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
561 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu'
37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
| ^
In file included from drivers/mailbox/arm_mhuv3.c:15:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:14:
In file included from arch/hexagon/include/asm/io.h:328:
include/asm-generic/io.h:574:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
574 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu'
35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
| ^
In file included from drivers/mailbox/arm_mhuv3.c:15:
In file included from include/linux/interrupt.h:11:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:14:
In file included from arch/hexagon/include/asm/io.h:328:
include/asm-generic/io.h:585:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
585 | __raw_writeb(value, PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:595:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
595 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:605:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
605 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
>> drivers/mailbox/arm_mhuv3.c:642:3: warning: variable 'fired_dbs' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
642 | scoped_guard(spinlock_irqsave, &e->pending_lock) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/mailbox/arm_mhuv3.c:650:3: note: uninitialized use occurs here
650 | fired_dbs &= ~BIT(*db);
| ^~~~~~~~~
drivers/mailbox/arm_mhuv3.c:642:3: note: remove the 'if' if its condition is always false
642 | scoped_guard(spinlock_irqsave, &e->pending_lock) {
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
drivers/mailbox/arm_mhuv3.c:634:28: note: initialize the variable 'fired_dbs' to silence this warning
634 | u32 active_dbs, fired_dbs;
| ^
| = 0
7 warnings generated.
..
Kconfig warnings: (for reference only)
WARNING: unmet direct dependencies detected for GET_FREE_REGION
Depends on [n]: SPARSEMEM [=n]
Selected by [y]:
- RESOURCE_KUNIT_TEST [=y] && RUNTIME_TESTING_MENU [=y] && KUNIT [=y]
vim +2277 sound/core/pcm_native.c
^1da177e4c3f41 Linus Torvalds 2005-04-16 2240
^1da177e4c3f41 Linus Torvalds 2005-04-16 2241 /*
^1da177e4c3f41 Linus Torvalds 2005-04-16 2242 * PCM link handling
^1da177e4c3f41 Linus Torvalds 2005-04-16 2243 */
877211f5e1b119 Takashi Iwai 2005-11-17 2244 static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
^1da177e4c3f41 Linus Torvalds 2005-04-16 2245 {
877211f5e1b119 Takashi Iwai 2005-11-17 2246 struct snd_pcm_file *pcm_file;
877211f5e1b119 Takashi Iwai 2005-11-17 2247 struct snd_pcm_substream *substream1;
ae921398486419 Takashi Iwai 2024-02-22 2248 struct snd_pcm_group *group __free(kfree) = NULL;
ae921398486419 Takashi Iwai 2024-02-22 2249 struct snd_pcm_group *target_group;
f57f3df03a8e60 Takashi Iwai 2019-01-13 2250 bool nonatomic = substream->pcm->nonatomic;
d90950c6a2658e Takashi Iwai 2024-02-23 2251 CLASS(fd, f)(fd);
^1da177e4c3f41 Linus Torvalds 2005-04-16 2252
1da91ea87aefe2 Al Viro 2024-05-31 2253 if (!fd_file(f))
^1da177e4c3f41 Linus Torvalds 2005-04-16 2254 return -EBADFD;
1da91ea87aefe2 Al Viro 2024-05-31 2255 if (!is_pcm_file(fd_file(f)))
d90950c6a2658e Takashi Iwai 2024-02-23 2256 return -EBADFD;
ae921398486419 Takashi Iwai 2024-02-22 2257
1da91ea87aefe2 Al Viro 2024-05-31 2258 pcm_file = fd_file(f)->private_data;
^1da177e4c3f41 Linus Torvalds 2005-04-16 2259 substream1 = pcm_file->substream;
951e2736f4b11b Michał Mirosław 2020-06-08 2260
d90950c6a2658e Takashi Iwai 2024-02-23 2261 if (substream == substream1)
d90950c6a2658e Takashi Iwai 2024-02-23 2262 return -EINVAL;
951e2736f4b11b Michał Mirosław 2020-06-08 2263
73365cb10b280e Takashi Iwai 2019-01-13 2264 group = kzalloc(sizeof(*group), GFP_KERNEL);
d90950c6a2658e Takashi Iwai 2024-02-23 2265 if (!group)
d90950c6a2658e Takashi Iwai 2024-02-23 2266 return -ENOMEM;
73365cb10b280e Takashi Iwai 2019-01-13 2267 snd_pcm_group_init(group);
f57f3df03a8e60 Takashi Iwai 2019-01-13 2268
dd0da75b9a2768 Takashi Iwai 2024-02-27 2269 guard(rwsem_write)(&snd_pcm_link_rwsem);
f0061c18c169f0 Takashi Iwai 2022-09-26 2270 if (substream->runtime->state == SNDRV_PCM_STATE_OPEN ||
f0061c18c169f0 Takashi Iwai 2022-09-26 2271 substream->runtime->state != substream1->runtime->state ||
dd0da75b9a2768 Takashi Iwai 2024-02-27 2272 substream->pcm->nonatomic != substream1->pcm->nonatomic)
dd0da75b9a2768 Takashi Iwai 2024-02-27 2273 return -EBADFD;
dd0da75b9a2768 Takashi Iwai 2024-02-27 2274 if (snd_pcm_stream_linked(substream1))
dd0da75b9a2768 Takashi Iwai 2024-02-27 2275 return -EALREADY;
f57f3df03a8e60 Takashi Iwai 2019-01-13 2276
650224fe8d5f6d Takashi Iwai 2024-02-27 @2277 scoped_guard(pcm_stream_lock_irq, substream) {
^1da177e4c3f41 Linus Torvalds 2005-04-16 2278 if (!snd_pcm_stream_linked(substream)) {
a41c4cb913b53b Takashi Iwai 2019-01-13 2279 snd_pcm_group_assign(substream, group);
f57f3df03a8e60 Takashi Iwai 2019-01-13 2280 group = NULL; /* assigned, don't free this one below */
^1da177e4c3f41 Linus Torvalds 2005-04-16 2281 }
f57f3df03a8e60 Takashi Iwai 2019-01-13 2282 target_group = substream->group;
650224fe8d5f6d Takashi Iwai 2024-02-27 2283 }
f57f3df03a8e60 Takashi Iwai 2019-01-13 2284
f57f3df03a8e60 Takashi Iwai 2019-01-13 2285 snd_pcm_group_lock_irq(target_group, nonatomic);
e18035cf5cb3d2 Michał Mirosław 2020-06-08 2286 snd_pcm_stream_lock_nested(substream1);
f57f3df03a8e60 Takashi Iwai 2019-01-13 2287 snd_pcm_group_assign(substream1, target_group);
0e279dcea0ec89 Takashi Iwai 2019-07-19 2288 refcount_inc(&target_group->refs);
f57f3df03a8e60 Takashi Iwai 2019-01-13 2289 snd_pcm_stream_unlock(substream1);
f57f3df03a8e60 Takashi Iwai 2019-01-13 2290 snd_pcm_group_unlock_irq(target_group, nonatomic);
dd0da75b9a2768 Takashi Iwai 2024-02-27 2291 return 0;
^1da177e4c3f41 Linus Torvalds 2005-04-16 2292 }
^1da177e4c3f41 Linus Torvalds 2005-04-16 2293
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Przemek,
kernel test robot noticed the following build warnings:
[auto build test WARNING on 44badc908f2c85711cb18e45e13119c10ad3a05f]
url: https://github.com/intel-lab-lkp/linux/commits/Przemek-Kitszel/cleanup-adjust-scoped_guard-macros-to-avoid-potential-warning/20241011-201702
base: 44badc908f2c85711cb18e45e13119c10ad3a05f
patch link: https://lore.kernel.org/r/20241011121535.28049-1-przemyslaw.kitszel%40intel.com
patch subject: [PATCH v3] cleanup: adjust scoped_guard() macros to avoid potential warning
config: i386-buildonly-randconfig-005-20241013 (https://download.01.org/0day-ci/archive/20241013/202410131151.SBnGQot0-lkp@intel.com/config)
compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241013/202410131151.SBnGQot0-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202410131151.SBnGQot0-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/firewire/core-device.c:1041:2: warning: variable 'found' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
1041 | scoped_guard(rwsem_read, &fw_device_rwsem) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/firewire/core-device.c:1045:6: note: uninitialized use occurs here
1045 | if (found) {
| ^~~~~
include/linux/compiler.h:55:47: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~
include/linux/compiler.h:57:52: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~
drivers/firewire/core-device.c:1041:2: note: remove the 'if' if its condition is always false
1041 | scoped_guard(rwsem_read, &fw_device_rwsem) {
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
drivers/firewire/core-device.c:1008:22: note: initialize the variable 'found' to silence this warning
1008 | struct device *found;
| ^
| = NULL
1 warning generated.
--
>> drivers/firewire/core-transaction.c:912:2: warning: variable 'handler' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
912 | scoped_guard(rcu) {
| ^~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/firewire/core-transaction.c:921:7: note: uninitialized use occurs here
921 | if (!handler)
| ^~~~~~~
include/linux/compiler.h:55:47: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~
include/linux/compiler.h:57:52: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~
drivers/firewire/core-transaction.c:912:2: note: remove the 'if' if its condition is always false
912 | scoped_guard(rcu) {
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
drivers/firewire/core-transaction.c:903:36: note: initialize the variable 'handler' to silence this warning
903 | struct fw_address_handler *handler;
| ^
| = NULL
1 warning generated.
--
>> drivers/firewire/core-cdev.c:508:2: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
508 | scoped_guard(spinlock_irqsave, &client->lock) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/firewire/core-cdev.c:530:9: note: uninitialized use occurs here
530 | return ret < 0 ? ret : 0;
| ^~~
drivers/firewire/core-cdev.c:508:2: note: remove the 'if' if its condition is always false
508 | scoped_guard(spinlock_irqsave, &client->lock) {
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
drivers/firewire/core-cdev.c:506:9: note: initialize the variable 'ret' to silence this warning
506 | int ret;
| ^
| = 0
>> drivers/firewire/core-cdev.c:1327:2: warning: variable 'skip' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
1327 | scoped_guard(spinlock_irq, &client->lock) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/firewire/core-cdev.c:1346:6: note: uninitialized use occurs here
1346 | if (skip)
| ^~~~
include/linux/compiler.h:55:47: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~
include/linux/compiler.h:57:52: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~
drivers/firewire/core-cdev.c:1327:2: note: remove the 'if' if its condition is always false
1327 | scoped_guard(spinlock_irq, &client->lock) {
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
drivers/firewire/core-cdev.c:1325:11: note: initialize the variable 'skip' to silence this warning
1325 | bool skip, free, success;
| ^
| = 0
2 warnings generated.
--
>> drivers/gpio/gpio-sim.c:179:2: warning: variable 'direction' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
179 | scoped_guard(mutex, &chip->lock)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpio/gpio-sim.c:182:9: note: uninitialized use occurs here
182 | return direction ? GPIO_LINE_DIRECTION_IN : GPIO_LINE_DIRECTION_OUT;
| ^~~~~~~~~
drivers/gpio/gpio-sim.c:179:2: note: remove the 'if' if its condition is always false
179 | scoped_guard(mutex, &chip->lock)
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
drivers/gpio/gpio-sim.c:177:15: note: initialize the variable 'direction' to silence this warning
177 | int direction;
| ^
| = 0
>> drivers/gpio/gpio-sim.c:277:2: warning: variable 'val' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
277 | scoped_guard(mutex, &chip->lock)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpio/gpio-sim.c:280:33: note: uninitialized use occurs here
280 | return sysfs_emit(buf, "%d\n", val);
| ^~~
drivers/gpio/gpio-sim.c:277:2: note: remove the 'if' if its condition is always false
277 | scoped_guard(mutex, &chip->lock)
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
drivers/gpio/gpio-sim.c:275:9: note: initialize the variable 'val' to silence this warning
275 | int val;
| ^
| = 0
>> drivers/gpio/gpio-sim.c:307:2: warning: variable 'pull' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
307 | scoped_guard(mutex, &chip->lock)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpio/gpio-sim.c:310:61: note: uninitialized use occurs here
310 | return sysfs_emit(buf, "%s\n", gpio_sim_sysfs_pull_strings[pull]);
| ^~~~
drivers/gpio/gpio-sim.c:307:2: note: remove the 'if' if its condition is always false
307 | scoped_guard(mutex, &chip->lock)
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
drivers/gpio/gpio-sim.c:305:10: note: initialize the variable 'pull' to silence this warning
305 | int pull;
| ^
| = 0
>> drivers/gpio/gpio-sim.c:756:2: warning: variable 'live' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
756 | scoped_guard(mutex, &dev->lock)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpio/gpio-sim.c:759:31: note: uninitialized use occurs here
759 | return sprintf(page, "%c\n", live ? '1' : '0');
| ^~~~
drivers/gpio/gpio-sim.c:756:2: note: remove the 'if' if its condition is always false
756 | scoped_guard(mutex, &dev->lock)
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
drivers/gpio/gpio-sim.c:754:11: note: initialize the variable 'live' to silence this warning
754 | bool live;
| ^
| = 0
>> drivers/gpio/gpio-sim.c:1266:2: warning: variable 'dir' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
1266 | scoped_guard(mutex, &dev->lock)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:55:28: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpio/gpio-sim.c:1269:10: note: uninitialized use occurs here
1269 | switch (dir) {
| ^~~
drivers/gpio/gpio-sim.c:1266:2: note: remove the 'if' if its condition is always false
1266 | scoped_guard(mutex, &dev->lock)
| ^
include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
| ^
include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
| ^
include/linux/compiler.h:55:23: note: expanded from macro 'if'
55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
| ^
drivers/gpio/gpio-sim.c:1264:9: note: initialize the variable 'dir' to silence this warning
1264 | int dir;
| ^
| = 0
5 warnings generated.
..
vim +1041 drivers/firewire/core-device.c
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1002
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1003 static void fw_device_init(struct work_struct *work)
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1004 {
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1005 struct fw_device *device =
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1006 container_of(work, struct fw_device, work.work);
26b4950de174bc drivers/firewire/core-device.c Stefan Richter 2012-02-18 1007 struct fw_card *card = device->card;
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1008 struct device *found;
7e5a7725a0e403 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-12 1009 u32 minor;
7e5a7725a0e403 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-12 1010 int ret;
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1011
c781c06d119d04 drivers/firewire/fw-device.c Kristian Høgsberg 2007-05-07 1012 /*
c781c06d119d04 drivers/firewire/fw-device.c Kristian Høgsberg 2007-05-07 1013 * All failure paths here set node->data to NULL, so that we
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1014 * don't try to do device_for_each_child() on a kfree()'d
c781c06d119d04 drivers/firewire/fw-device.c Kristian Høgsberg 2007-05-07 1015 * device.
c781c06d119d04 drivers/firewire/fw-device.c Kristian Høgsberg 2007-05-07 1016 */
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1017
94fba9fbeac444 drivers/firewire/core-device.c Clemens Ladisch 2012-04-11 1018 ret = read_config_rom(device, device->generation);
94fba9fbeac444 drivers/firewire/core-device.c Clemens Ladisch 2012-04-11 1019 if (ret != RCODE_COMPLETE) {
855c603d61ede7 drivers/firewire/fw-device.c Stefan Richter 2008-02-27 1020 if (device->config_rom_retries < MAX_RETRIES &&
855c603d61ede7 drivers/firewire/fw-device.c Stefan Richter 2008-02-27 1021 atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1022 device->config_rom_retries++;
6ea9e7bbfc389a drivers/firewire/core-device.c Stefan Richter 2010-10-13 1023 fw_schedule_device_work(device, RETRY_DELAY);
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1024 } else {
115881d395959b drivers/firewire/core-device.c Stefan Richter 2011-03-15 1025 if (device->node->link_on)
94fba9fbeac444 drivers/firewire/core-device.c Clemens Ladisch 2012-04-11 1026 fw_notice(card, "giving up on node %x: reading config rom failed: %s\n",
94fba9fbeac444 drivers/firewire/core-device.c Clemens Ladisch 2012-04-11 1027 device->node_id,
94fba9fbeac444 drivers/firewire/core-device.c Clemens Ladisch 2012-04-11 1028 fw_rcode_string(ret));
26b4950de174bc drivers/firewire/core-device.c Stefan Richter 2012-02-18 1029 if (device->node == card->root_node)
26b4950de174bc drivers/firewire/core-device.c Stefan Richter 2012-02-18 1030 fw_schedule_bm_work(card, 0);
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1031 fw_device_release(&device->device);
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1032 }
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1033 return;
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1034 }
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1035
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1036 // If a device was pending for deletion because its node went away but its bus info block
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1037 // and root directory header matches that of a newly discovered device, revive the
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1038 // existing fw_device. The newly allocated fw_device becomes obsolete instead.
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1039 //
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1040 // serialize config_rom access.
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 @1041 scoped_guard(rwsem_read, &fw_device_rwsem) {
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1042 found = device_find_child(card->device, (void *)device->config_rom,
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1043 compare_configuration_rom);
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1044 }
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1045 if (found) {
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1046 struct fw_device *reused = fw_device(found);
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1047
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1048 if (atomic_cmpxchg(&reused->state,
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1049 FW_DEVICE_GONE,
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1050 FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1051 // serialize node access
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1052 scoped_guard(spinlock_irq, &card->lock) {
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1053 struct fw_node *current_node = device->node;
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1054 struct fw_node *obsolete_node = reused->node;
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1055
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1056 device->node = obsolete_node;
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1057 device->node->data = device;
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1058 reused->node = current_node;
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1059 reused->node->data = reused;
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1060
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1061 reused->max_speed = device->max_speed;
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1062 reused->node_id = current_node->node_id;
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1063 smp_wmb(); /* update node_id before generation */
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1064 reused->generation = card->generation;
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1065 reused->config_rom_retries = 0;
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1066 fw_notice(card, "rediscovered device %s\n",
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1067 dev_name(found));
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1068
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1069 reused->workfn = fw_device_update;
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1070 fw_schedule_device_work(reused, 0);
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1071
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1072 if (current_node == card->root_node)
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1073 fw_schedule_bm_work(card, 0);
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1074 }
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1075
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1076 put_device(found);
3d36a0df3b473f drivers/firewire/fw-device.c Stefan Richter 2009-01-17 1077 fw_device_release(&device->device);
3d36a0df3b473f drivers/firewire/fw-device.c Stefan Richter 2009-01-17 1078
3d36a0df3b473f drivers/firewire/fw-device.c Stefan Richter 2009-01-17 1079 return;
3d36a0df3b473f drivers/firewire/fw-device.c Stefan Richter 2009-01-17 1080 }
3d36a0df3b473f drivers/firewire/fw-device.c Stefan Richter 2009-01-17 1081
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1082 put_device(found);
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1083 }
e2c87f484190b1 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-20 1084
6230582320b721 drivers/firewire/fw-device.c Stefan Richter 2009-01-09 1085 device_initialize(&device->device);
96b19062e741b7 drivers/firewire/fw-device.c Stefan Richter 2008-02-02 1086
96b19062e741b7 drivers/firewire/fw-device.c Stefan Richter 2008-02-02 1087 fw_device_get(device);
7e5a7725a0e403 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-12 1088
7e5a7725a0e403 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-12 1089 // The index of allocated entry is used for minor identifier of device node.
7e5a7725a0e403 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-12 1090 ret = xa_alloc(&fw_device_xa, &minor, device, XA_LIMIT(0, MINORMASK), GFP_KERNEL);
7e5a7725a0e403 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-12 1091 if (ret < 0)
a3aca3dabbcf00 drivers/firewire/fw-device.c Kristian Høgsberg 2007-03-07 1092 goto error;
a3aca3dabbcf00 drivers/firewire/fw-device.c Kristian Høgsberg 2007-03-07 1093
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1094 device->device.bus = &fw_bus_type;
21351dbe4e6127 drivers/firewire/fw-device.c Kristian Høgsberg 2007-03-20 1095 device->device.type = &fw_device_type;
26b4950de174bc drivers/firewire/core-device.c Stefan Richter 2012-02-18 1096 device->device.parent = card->device;
a3aca3dabbcf00 drivers/firewire/fw-device.c Kristian Høgsberg 2007-03-07 1097 device->device.devt = MKDEV(fw_cdev_major, minor);
a1f64819fe9f13 drivers/firewire/fw-device.c Kay Sievers 2008-10-30 1098 dev_set_name(&device->device, "fw%d", minor);
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1099
e5333db9285e08 drivers/firewire/fw-device.c Stefan Richter 2009-05-22 1100 BUILD_BUG_ON(ARRAY_SIZE(device->attribute_group.attrs) <
e5333db9285e08 drivers/firewire/fw-device.c Stefan Richter 2009-05-22 1101 ARRAY_SIZE(fw_device_attributes) +
e5333db9285e08 drivers/firewire/fw-device.c Stefan Richter 2009-05-22 1102 ARRAY_SIZE(config_rom_attributes));
6f2e53d5135a86 drivers/firewire/fw-device.c Kristian Høgsberg 2007-03-27 1103 init_fw_attribute_group(&device->device,
6f2e53d5135a86 drivers/firewire/fw-device.c Kristian Høgsberg 2007-03-27 1104 fw_device_attributes,
6f2e53d5135a86 drivers/firewire/fw-device.c Kristian Høgsberg 2007-03-27 1105 &device->attribute_group);
e5333db9285e08 drivers/firewire/fw-device.c Stefan Richter 2009-05-22 1106
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1107 if (device_add(&device->device)) {
26b4950de174bc drivers/firewire/core-device.c Stefan Richter 2012-02-18 1108 fw_err(card, "failed to add device\n");
a3aca3dabbcf00 drivers/firewire/fw-device.c Kristian Høgsberg 2007-03-07 1109 goto error_with_cdev;
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1110 }
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1111
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1112 create_units(device);
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1113
c781c06d119d04 drivers/firewire/fw-device.c Kristian Høgsberg 2007-05-07 1114 /*
c781c06d119d04 drivers/firewire/fw-device.c Kristian Høgsberg 2007-05-07 1115 * Transition the device to running state. If it got pulled
183b8021fc0a5f drivers/firewire/core-device.c Masahiro Yamada 2017-02-27 1116 * out from under us while we did the initialization work, we
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1117 * have to shut down the device again here. Normally, though,
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1118 * fw_node_event will be responsible for shutting it down when
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1119 * necessary. We have to use the atomic cmpxchg here to avoid
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1120 * racing with the FW_NODE_DESTROYED case in
c781c06d119d04 drivers/firewire/fw-device.c Kristian Høgsberg 2007-05-07 1121 * fw_node_event().
c781c06d119d04 drivers/firewire/fw-device.c Kristian Høgsberg 2007-05-07 1122 */
641f8791f031d6 drivers/firewire/fw-device.c Stefan Richter 2007-01-27 1123 if (atomic_cmpxchg(&device->state,
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1124 FW_DEVICE_INITIALIZING,
3d36a0df3b473f drivers/firewire/fw-device.c Stefan Richter 2009-01-17 1125 FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
70044d71d31d69 drivers/firewire/core-device.c Tejun Heo 2014-03-07 1126 device->workfn = fw_device_shutdown;
6ea9e7bbfc389a drivers/firewire/core-device.c Stefan Richter 2010-10-13 1127 fw_schedule_device_work(device, SHUTDOWN_DELAY);
fa6e697b85d705 drivers/firewire/fw-device.c Stefan Richter 2008-02-03 1128 } else {
26b4950de174bc drivers/firewire/core-device.c Stefan Richter 2012-02-18 1129 fw_notice(card, "created device %s: GUID %08x%08x, S%d00\n",
a1f64819fe9f13 drivers/firewire/fw-device.c Kay Sievers 2008-10-30 1130 dev_name(&device->device),
fa6e697b85d705 drivers/firewire/fw-device.c Stefan Richter 2008-02-03 1131 device->config_rom[3], device->config_rom[4],
f1397490017e33 drivers/firewire/fw-device.c Stefan Richter 2007-06-10 1132 1 << device->max_speed);
c9755e14a01987 drivers/firewire/fw-device.c Stefan Richter 2008-03-24 1133 device->config_rom_retries = 0;
7889b60ee71eaf drivers/firewire/fw-device.c Stefan Richter 2009-03-10 1134
099d54143e49d4 drivers/firewire/core-device.c Stefan Richter 2009-06-06 1135 set_broadcast_channel(device, device->generation);
badfcb24891ccd drivers/firewire/core-device.c Clemens Ladisch 2012-08-13 1136
badfcb24891ccd drivers/firewire/core-device.c Clemens Ladisch 2012-08-13 1137 add_device_randomness(&device->config_rom[3], 8);
fa6e697b85d705 drivers/firewire/fw-device.c Stefan Richter 2008-02-03 1138 }
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1139
c781c06d119d04 drivers/firewire/fw-device.c Kristian Høgsberg 2007-05-07 1140 /*
c781c06d119d04 drivers/firewire/fw-device.c Kristian Høgsberg 2007-05-07 1141 * Reschedule the IRM work if we just finished reading the
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1142 * root node config rom. If this races with a bus reset we
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1143 * just end up running the IRM work a couple of extra times -
c781c06d119d04 drivers/firewire/fw-device.c Kristian Høgsberg 2007-05-07 1144 * pretty harmless.
c781c06d119d04 drivers/firewire/fw-device.c Kristian Høgsberg 2007-05-07 1145 */
26b4950de174bc drivers/firewire/core-device.c Stefan Richter 2012-02-18 1146 if (device->node == card->root_node)
26b4950de174bc drivers/firewire/core-device.c Stefan Richter 2012-02-18 1147 fw_schedule_bm_work(card, 0);
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1148
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1149 return;
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1150
a3aca3dabbcf00 drivers/firewire/fw-device.c Kristian Høgsberg 2007-03-07 1151 error_with_cdev:
7e5a7725a0e403 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-12 1152 xa_erase(&fw_device_xa, minor);
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1153 error:
7e5a7725a0e403 drivers/firewire/core-device.c Takashi Sakamoto 2024-08-12 1154 fw_device_put(device); // fw_device_xa's reference.
96b19062e741b7 drivers/firewire/fw-device.c Stefan Richter 2008-02-02 1155
96b19062e741b7 drivers/firewire/fw-device.c Stefan Richter 2008-02-02 1156 put_device(&device->device); /* our reference */
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1157 }
19a15b937b2663 drivers/firewire/fw-device.c Kristian Høgsberg 2006-12-19 1158
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
On Sun, Oct 13, 2024 at 12:01:24PM +0800, kernel test robot wrote:
> >> drivers/firewire/core-transaction.c:912:2: warning: variable 'handler' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
> 912 | scoped_guard(rcu) {
> | ^~~~~~~~~~~~~~~~~
> include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
> 197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
> 190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/compiler.h:55:28: note: expanded from macro 'if'
> 55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
> 57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/firewire/core-transaction.c:921:7: note: uninitialized use occurs here
> 921 | if (!handler)
> | ^~~~~~~
> include/linux/compiler.h:55:47: note: expanded from macro 'if'
> 55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
> | ^~~~
> include/linux/compiler.h:57:52: note: expanded from macro '__trace_if_var'
> 57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
> | ^~~~
> drivers/firewire/core-transaction.c:912:2: note: remove the 'if' if its condition is always false
> 912 | scoped_guard(rcu) {
> | ^
> include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
> 197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
> | ^
> include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
> 190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
> | ^
> include/linux/compiler.h:55:23: note: expanded from macro 'if'
> 55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
> | ^
> drivers/firewire/core-transaction.c:903:36: note: initialize the variable 'handler' to silence this warning
> 903 | struct fw_address_handler *handler;
> | ^
> | = NULL
> 1 warning generated.
So this goes away when we do:
--- a/include/linux/cleanup.h
+++ b/include/linux/cleanup.h
@@ -323,7 +323,7 @@ static __maybe_unused const bool class_#
*/
#define __scoped_guard(_name, _fail, _label, args...) \
for (CLASS(_name, scope)(args); true; ({ goto _label; })) \
- if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
+ if (__is_cond_ptr(_name) && !__guard_ptr(_name)(&scope)) { \
_fail; \
_label: \
break; \
On 10/18/24 12:50, Peter Zijlstra wrote:
> On Sun, Oct 13, 2024 at 12:01:24PM +0800, kernel test robot wrote:
>>>> drivers/firewire/core-transaction.c:912:2: warning: variable 'handler' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
>> 912 | scoped_guard(rcu) {
>> | ^~~~~~~~~~~~~~~~~
>> include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
>> 197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
>> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
>> 190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
>> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> include/linux/compiler.h:55:28: note: expanded from macro 'if'
>> 55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
>> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> include/linux/compiler.h:57:30: note: expanded from macro '__trace_if_var'
>> 57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
>> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> drivers/firewire/core-transaction.c:921:7: note: uninitialized use occurs here
>> 921 | if (!handler)
>> | ^~~~~~~
>> include/linux/compiler.h:55:47: note: expanded from macro 'if'
>> 55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
>> | ^~~~
>> include/linux/compiler.h:57:52: note: expanded from macro '__trace_if_var'
>> 57 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond))
>> | ^~~~
>> drivers/firewire/core-transaction.c:912:2: note: remove the 'if' if its condition is always false
>> 912 | scoped_guard(rcu) {
>> | ^
>> include/linux/cleanup.h:197:2: note: expanded from macro 'scoped_guard'
>> 197 | __scoped_guard(_name, /* empty */, __UNIQUE_ID(label), args)
>> | ^
>> include/linux/cleanup.h:190:3: note: expanded from macro '__scoped_guard'
>> 190 | if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
>> | ^
>> include/linux/compiler.h:55:23: note: expanded from macro 'if'
>> 55 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
>> | ^
>> drivers/firewire/core-transaction.c:903:36: note: initialize the variable 'handler' to silence this warning
>> 903 | struct fw_address_handler *handler;
>> | ^
>> | = NULL
>> 1 warning generated.
>
> So this goes away when we do:
>
> --- a/include/linux/cleanup.h
> +++ b/include/linux/cleanup.h
> @@ -323,7 +323,7 @@ static __maybe_unused const bool class_#
> */
> #define __scoped_guard(_name, _fail, _label, args...) \
> for (CLASS(_name, scope)(args); true; ({ goto _label; })) \
> - if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
> + if (__is_cond_ptr(_name) && !__guard_ptr(_name)(&scope)) { \
but this will purge the attempt to call __guard_ptr(), and thus newer
lock ;) good that there is at least some comment above
FTR, I have resolved this via v4
https://lore.kernel.org/netdev/20241018113823.171256-1-przemyslaw.kitszel@intel.com/T/
> _fail; \
> _label: \
> break; \
On Wed, Oct 23, 2024 at 03:43:22PM +0200, Przemek Kitszel wrote:
> On 10/18/24 12:50, Peter Zijlstra wrote:
> > On Sun, Oct 13, 2024 at 12:01:24PM +0800, kernel test robot wrote:
> > --- a/include/linux/cleanup.h
> > +++ b/include/linux/cleanup.h
> > @@ -323,7 +323,7 @@ static __maybe_unused const bool class_#
> > */
> > #define __scoped_guard(_name, _fail, _label, args...) \
> > for (CLASS(_name, scope)(args); true; ({ goto _label; })) \
> > - if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
> > + if (__is_cond_ptr(_name) && !__guard_ptr(_name)(&scope)) { \
>
> but this will purge the attempt to call __guard_ptr(), and thus newer
> lock ;) good that there is at least some comment above
No, __guard_ptr() will only return a pointer, it has no action. The lock
callback is in CLASS(_name, scope)(args).
On 10/23/24 16:32, Peter Zijlstra wrote:
> On Wed, Oct 23, 2024 at 03:43:22PM +0200, Przemek Kitszel wrote:
>> On 10/18/24 12:50, Peter Zijlstra wrote:
>>> On Sun, Oct 13, 2024 at 12:01:24PM +0800, kernel test robot wrote:
>
>>> --- a/include/linux/cleanup.h
>>> +++ b/include/linux/cleanup.h
>>> @@ -323,7 +323,7 @@ static __maybe_unused const bool class_#
>>> */
>>> #define __scoped_guard(_name, _fail, _label, args...) \
>>> for (CLASS(_name, scope)(args); true; ({ goto _label; })) \
>>> - if (!__guard_ptr(_name)(&scope) && __is_cond_ptr(_name)) { \
>>> + if (__is_cond_ptr(_name) && !__guard_ptr(_name)(&scope)) { \
>>
>> but this will purge the attempt to call __guard_ptr(), and thus newer
>> lock ;) good that there is at least some comment above
>
> No, __guard_ptr() will only return a pointer, it has no action. The lock
> callback is in CLASS(_name, scope)(args).
Ach, true! Thanks again for taking a look at my series!
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