Re: [PATCH v2] writeback: safer lock nesting
From: kbuild test robot
Date: Sat Apr 07 2018 - 15:04:32 EST
Hi Greg,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on linus/master]
[also build test WARNING on v4.16]
[cannot apply to next-20180406]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Greg-Thelen/writeback-safer-lock-nesting/20180407-122200
config: mips-db1xxx_defconfig (attached as .config)
compiler: mipsel-linux-gnu-gcc (Debian 7.2.0-11) 7.2.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=mips
Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings
All warnings (new ones prefixed by >>):
In file included from arch/mips/include/asm/atomic.h:17:0,
from include/linux/atomic.h:5,
from arch/mips/include/asm/processor.h:14,
from arch/mips/include/asm/thread_info.h:16,
from include/linux/thread_info.h:38,
from include/asm-generic/preempt.h:5,
from ./arch/mips/include/generated/asm/preempt.h:1,
from include/linux/preempt.h:81,
from include/linux/spinlock.h:51,
from mm/page-writeback.c:16:
mm/page-writeback.c: In function 'account_page_redirty':
>> include/linux/irqflags.h:80:3: warning: 'cookie.flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
arch_local_irq_restore(flags); \
^~~~~~~~~~~~~~~~~~~~~~
mm/page-writeback.c:2504:25: note: 'cookie.flags' was declared here
struct wb_lock_cookie cookie;
^~~~~~
In file included from arch/mips/include/asm/atomic.h:17:0,
from include/linux/atomic.h:5,
from arch/mips/include/asm/processor.h:14,
from arch/mips/include/asm/thread_info.h:16,
from include/linux/thread_info.h:38,
from include/asm-generic/preempt.h:5,
from ./arch/mips/include/generated/asm/preempt.h:1,
from include/linux/preempt.h:81,
from include/linux/spinlock.h:51,
from mm/page-writeback.c:16:
mm/page-writeback.c: In function '__cancel_dirty_page':
>> include/linux/irqflags.h:80:3: warning: 'cookie.flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
arch_local_irq_restore(flags); \
^~~~~~~~~~~~~~~~~~~~~~
mm/page-writeback.c:2616:25: note: 'cookie.flags' was declared here
struct wb_lock_cookie cookie;
^~~~~~
In file included from arch/mips/include/asm/atomic.h:17:0,
from include/linux/atomic.h:5,
from arch/mips/include/asm/processor.h:14,
from arch/mips/include/asm/thread_info.h:16,
from include/linux/thread_info.h:38,
from include/asm-generic/preempt.h:5,
from ./arch/mips/include/generated/asm/preempt.h:1,
from include/linux/preempt.h:81,
from include/linux/spinlock.h:51,
from mm/page-writeback.c:16:
mm/page-writeback.c: In function 'clear_page_dirty_for_io':
>> include/linux/irqflags.h:80:3: warning: 'cookie.flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
arch_local_irq_restore(flags); \
^~~~~~~~~~~~~~~~~~~~~~
mm/page-writeback.c:2656:25: note: 'cookie.flags' was declared here
struct wb_lock_cookie cookie;
^~~~~~
vim +80 include/linux/irqflags.h
81d68a96 Steven Rostedt 2008-05-12 66
df9ee292 David Howells 2010-10-07 67 /*
df9ee292 David Howells 2010-10-07 68 * Wrap the arch provided IRQ routines to provide appropriate checks.
df9ee292 David Howells 2010-10-07 69 */
df9ee292 David Howells 2010-10-07 70 #define raw_local_irq_disable() arch_local_irq_disable()
df9ee292 David Howells 2010-10-07 71 #define raw_local_irq_enable() arch_local_irq_enable()
df9ee292 David Howells 2010-10-07 72 #define raw_local_irq_save(flags) \
df9ee292 David Howells 2010-10-07 73 do { \
df9ee292 David Howells 2010-10-07 74 typecheck(unsigned long, flags); \
df9ee292 David Howells 2010-10-07 75 flags = arch_local_irq_save(); \
df9ee292 David Howells 2010-10-07 76 } while (0)
df9ee292 David Howells 2010-10-07 77 #define raw_local_irq_restore(flags) \
df9ee292 David Howells 2010-10-07 78 do { \
df9ee292 David Howells 2010-10-07 79 typecheck(unsigned long, flags); \
df9ee292 David Howells 2010-10-07 @80 arch_local_irq_restore(flags); \
df9ee292 David Howells 2010-10-07 81 } while (0)
df9ee292 David Howells 2010-10-07 82 #define raw_local_save_flags(flags) \
df9ee292 David Howells 2010-10-07 83 do { \
df9ee292 David Howells 2010-10-07 84 typecheck(unsigned long, flags); \
df9ee292 David Howells 2010-10-07 85 flags = arch_local_save_flags(); \
df9ee292 David Howells 2010-10-07 86 } while (0)
df9ee292 David Howells 2010-10-07 87 #define raw_irqs_disabled_flags(flags) \
df9ee292 David Howells 2010-10-07 88 ({ \
df9ee292 David Howells 2010-10-07 89 typecheck(unsigned long, flags); \
df9ee292 David Howells 2010-10-07 90 arch_irqs_disabled_flags(flags); \
df9ee292 David Howells 2010-10-07 91 })
df9ee292 David Howells 2010-10-07 92 #define raw_irqs_disabled() (arch_irqs_disabled())
df9ee292 David Howells 2010-10-07 93 #define raw_safe_halt() arch_safe_halt()
de30a2b3 Ingo Molnar 2006-07-03 94
:::::: The code at line 80 was first introduced by commit
:::::: df9ee29270c11dba7d0fe0b83ce47a4d8e8d2101 Fix IRQ flag handling naming
:::::: TO: David Howells <dhowells@xxxxxxxxxx>
:::::: CC: David Howells <dhowells@xxxxxxxxxx>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
Attachment:
.config.gz
Description: application/gzip