From b48ccb095a0c9257241261ec2bd1cbb1bdabc48b Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 23 Apr 2009 09:36:52 +0200 Subject: locking: clarify kernel-taint warning message Andi Kleen reported this message triggering on non-lockdep kernels: Disabling lockdep due to kernel taint Clarify the message to say 'lock debugging' - debug_locks_off() turns off all things lock debugging, not just lockdep. [ Impact: change kernel warning message text ] Reported-by: Andi Kleen Cc: Peter Zijlstra Cc: Andrew Morton Signed-off-by: Ingo Molnar --- kernel/panic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/panic.c') diff --git a/kernel/panic.c b/kernel/panic.c index 934fb377f4b3..3dcaa1661357 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -221,7 +221,7 @@ void add_taint(unsigned flag) * post-warning case. */ if (flag != TAINT_CRAP && flag != TAINT_WARN && __debug_locks_off()) - printk(KERN_WARNING "Disabling lockdep due to kernel taint\n"); + printk(KERN_WARNING "Disabling lock debugging due to kernel taint\n"); set_bit(flag, &tainted_mask); } -- cgit v1.2.2 From 57adc4d2dbf968fdbe516359688094eef4d46581 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 6 May 2009 16:02:53 -0700 Subject: Eliminate thousands of warnings with gcc 3.2 build When building with gcc 3.2 I get thousands of warnings such as include/linux/gfp.h: In function `allocflags_to_migratetype': include/linux/gfp.h:105: warning: null format string due to passing a NULL format string to warn_slowpath() in #define __WARN() warn_slowpath(__FILE__, __LINE__, NULL) Split this case out into a separate call. This also shrinks the kernel slightly: text data bss dec hex filename 4802274 707668 712704 6222646 5ef336 vmlinux text data bss dec hex filename 4799027 703572 712704 6215303 5ed687 vmlinux due to removeing one argument from the commonly-called __WARN(). [akpm@linux-foundation.org: reduce scope of `empty'] Acked-by: Jesper Nilsson Acked-by: Johannes Weiner Acked-by: Arjan van de Ven Signed-off-by: Andi Kleen Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/panic.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'kernel/panic.c') diff --git a/kernel/panic.c b/kernel/panic.c index 3dcaa1661357..874ecf1307ae 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -340,7 +340,7 @@ void oops_exit(void) } #ifdef WANT_WARN_ON_SLOWPATH -void warn_slowpath(const char *file, int line, const char *fmt, ...) +void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...) { va_list args; char function[KSYM_SYMBOL_LEN]; @@ -356,7 +356,7 @@ void warn_slowpath(const char *file, int line, const char *fmt, ...) if (board) printk(KERN_WARNING "Hardware name: %s\n", board); - if (fmt) { + if (*fmt) { va_start(args, fmt); vprintk(fmt, args); va_end(args); @@ -367,7 +367,14 @@ void warn_slowpath(const char *file, int line, const char *fmt, ...) print_oops_end_marker(); add_taint(TAINT_WARN); } -EXPORT_SYMBOL(warn_slowpath); +EXPORT_SYMBOL(warn_slowpath_fmt); + +void warn_slowpath_null(const char *file, int line) +{ + static const char *empty = ""; + warn_slowpath_fmt(file, line, empty); +} +EXPORT_SYMBOL(warn_slowpath_null); #endif #ifdef CONFIG_CC_STACKPROTECTOR -- cgit v1.2.2 From 0f6f49a8cd0163fdb1723ed29f01fc65177108dc Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 May 2009 13:41:28 -0700 Subject: Fix caller information for warn_slowpath_null Ian Campbell noticed that since "Eliminate thousands of warnings with gcc 3.2 build" (commit 57adc4d2dbf968fdbe516359688094eef4d46581) all WARN_ON()'s currently appear to come from warn_slowpath_null(), eg: WARNING: at kernel/softirq.c:143 warn_slowpath_null+0x1c/0x20() because now that warn_slowpath_null() is in the call path, the __builtin_return_address(0) returns that, rather than the place that caused the warning. Fix this by splitting up the warn_slowpath_null/fmt cases differently, using a common helper function, and getting the return address in the right place. This also happens to avoid the unnecessary stack usage for the non-stdargs case, and just generally cleans things up. Make the function name printout use %pS while at it. Cc: Ian Campbell Cc: Jesper Nilsson Cc: Johannes Weiner Cc: Arjan van de Ven Cc: Andi Kleen Cc: Hugh Dickins Cc: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/panic.c | 35 ++++++++++++++++++++--------------- 1 file changed, 20 insertions(+), 15 deletions(-) (limited to 'kernel/panic.c') diff --git a/kernel/panic.c b/kernel/panic.c index 874ecf1307ae..984b3ecbd72c 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -340,39 +340,44 @@ void oops_exit(void) } #ifdef WANT_WARN_ON_SLOWPATH -void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...) -{ +struct slowpath_args { + const char *fmt; va_list args; - char function[KSYM_SYMBOL_LEN]; - unsigned long caller = (unsigned long)__builtin_return_address(0); - const char *board; +}; - sprint_symbol(function, caller); +static void warn_slowpath_common(const char *file, int line, void *caller, struct slowpath_args *args) +{ + const char *board; printk(KERN_WARNING "------------[ cut here ]------------\n"); - printk(KERN_WARNING "WARNING: at %s:%d %s()\n", file, - line, function); + printk(KERN_WARNING "WARNING: at %s:%d %pS()\n", file, line, caller); board = dmi_get_system_info(DMI_PRODUCT_NAME); if (board) printk(KERN_WARNING "Hardware name: %s\n", board); - if (*fmt) { - va_start(args, fmt); - vprintk(fmt, args); - va_end(args); - } + if (args) + vprintk(args->fmt, args->args); print_modules(); dump_stack(); print_oops_end_marker(); add_taint(TAINT_WARN); } + +void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...) +{ + struct slowpath_args args; + + args.fmt = fmt; + va_start(args.args, fmt); + warn_slowpath_common(file, line, __builtin_return_address(0), &args); + va_end(args.args); +} EXPORT_SYMBOL(warn_slowpath_fmt); void warn_slowpath_null(const char *file, int line) { - static const char *empty = ""; - warn_slowpath_fmt(file, line, empty); + warn_slowpath_common(file, line, __builtin_return_address(0), NULL); } EXPORT_SYMBOL(warn_slowpath_null); #endif -- cgit v1.2.2