panic: Allow warnings to set different taint flags

WARN() is used in some places to report firmware or hardware bugs that
are then worked-around.  These bugs do not affect the stability of the
kernel and should not set the flag for TAINT_WARN.  To allow for this,
add WARN_TAINT() and WARN_TAINT_ONCE() macros that take a taint number
as argument.

Architectures that implement warnings using trap instructions instead
of calls to warn_slowpath_*() now implement __WARN_TAINT(taint)
instead of __WARN().

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Helge Deller <deller@gmx.de>
Tested-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This commit is contained in:
Ben Hutchings 2010-04-03 19:34:56 +01:00 committed by David Woodhouse
parent 8954da1f82
commit b2be05273a
8 changed files with 67 additions and 20 deletions

View File

@ -256,6 +256,7 @@ characters, each representing a particular tainted value.
9: 'A' if the ACPI table has been overridden.
10: 'W' if a warning has previously been issued by the kernel.
(Though some warnings may set more specific taint flags.)
11: 'C' if a staging driver has been loaded.

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@ -44,7 +44,7 @@
#endif
#ifdef CONFIG_DEBUG_BUGVERBOSE
#define __WARN() \
#define __WARN_TAINT(taint) \
do { \
asm volatile("\n" \
"1:\t" PARISC_BUG_BREAK_ASM "\n" \
@ -54,11 +54,11 @@
"\t.org 2b+%c3\n" \
"\t.popsection" \
: : "i" (__FILE__), "i" (__LINE__), \
"i" (BUGFLAG_WARNING), \
"i" (BUGFLAG_TAINT(taint)), \
"i" (sizeof(struct bug_entry)) ); \
} while(0)
#else
#define __WARN() \
#define __WARN_TAINT(taint) \
do { \
asm volatile("\n" \
"1:\t" PARISC_BUG_BREAK_ASM "\n" \
@ -67,7 +67,7 @@
"\t.short %c0\n" \
"\t.org 2b+%c1\n" \
"\t.popsection" \
: : "i" (BUGFLAG_WARNING), \
: : "i" (BUGFLAG_TAINT(taint)), \
"i" (sizeof(struct bug_entry)) ); \
} while(0)
#endif

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@ -85,12 +85,12 @@
} \
} while (0)
#define __WARN() do { \
#define __WARN_TAINT(taint) do { \
__asm__ __volatile__( \
"1: twi 31,0,0\n" \
_EMIT_BUG_ENTRY \
: : "i" (__FILE__), "i" (__LINE__), \
"i" (BUGFLAG_WARNING), \
"i" (BUGFLAG_TAINT(taint)), \
"i" (sizeof(struct bug_entry))); \
} while (0)
@ -104,7 +104,7 @@
"1: "PPC_TLNEI" %4,0\n" \
_EMIT_BUG_ENTRY \
: : "i" (__FILE__), "i" (__LINE__), \
"i" (BUGFLAG_WARNING), \
"i" (BUGFLAG_TAINT(TAINT_WARN)), \
"i" (sizeof(struct bug_entry)), \
"r" (__ret_warn_on)); \
} \

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@ -46,18 +46,18 @@
unreachable(); \
} while (0)
#define __WARN() do { \
__EMIT_BUG(BUGFLAG_WARNING); \
#define __WARN_TAINT(taint) do { \
__EMIT_BUG(BUGFLAG_TAINT(taint)); \
} while (0)
#define WARN_ON(x) ({ \
int __ret_warn_on = !!(x); \
if (__builtin_constant_p(__ret_warn_on)) { \
if (__ret_warn_on) \
__EMIT_BUG(BUGFLAG_WARNING); \
__WARN(); \
} else { \
if (unlikely(__ret_warn_on)) \
__EMIT_BUG(BUGFLAG_WARNING); \
__WARN(); \
} \
unlikely(__ret_warn_on); \
})

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@ -48,7 +48,7 @@ do { \
"i" (sizeof(struct bug_entry))); \
} while (0)
#define __WARN() \
#define __WARN_TAINT(taint) \
do { \
__asm__ __volatile__ ( \
"1:\t.short %O0\n" \
@ -57,7 +57,7 @@ do { \
: "n" (TRAPA_BUG_OPCODE), \
"i" (__FILE__), \
"i" (__LINE__), \
"i" (BUGFLAG_WARNING), \
"i" (BUGFLAG_TAINT(taint)), \
"i" (sizeof(struct bug_entry))); \
} while (0)

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@ -25,7 +25,10 @@ struct bug_entry {
};
#endif /* __ASSEMBLY__ */
#define BUGFLAG_WARNING (1<<0)
#define BUGFLAG_WARNING (1 << 0)
#define BUGFLAG_TAINT(taint) (BUGFLAG_WARNING | ((taint) << 8))
#define BUG_GET_TAINT(bug) ((bug)->flags >> 8)
#endif /* CONFIG_GENERIC_BUG */
/*
@ -56,17 +59,25 @@ struct bug_entry {
* appear at runtime. Use the versions with printk format strings
* to provide better diagnostics.
*/
#ifndef __WARN
#ifndef __WARN_TAINT
#ifndef __ASSEMBLY__
extern void warn_slowpath_fmt(const char *file, const int line,
const char *fmt, ...) __attribute__((format(printf, 3, 4)));
extern void warn_slowpath_fmt_taint(const char *file, const int line,
unsigned taint, const char *fmt, ...)
__attribute__((format(printf, 4, 5)));
extern void warn_slowpath_null(const char *file, const int line);
#define WANT_WARN_ON_SLOWPATH
#endif
#define __WARN() warn_slowpath_null(__FILE__, __LINE__)
#define __WARN_printf(arg...) warn_slowpath_fmt(__FILE__, __LINE__, arg)
#define __WARN_printf_taint(taint, arg...) \
warn_slowpath_fmt_taint(__FILE__, __LINE__, taint, arg)
#else
#define __WARN() __WARN_TAINT(TAINT_WARN)
#define __WARN_printf(arg...) do { printk(arg); __WARN(); } while (0)
#define __WARN_printf_taint(taint, arg...) \
do { printk(arg); __WARN_TAINT(taint); } while (0)
#endif
#ifndef WARN_ON
@ -87,6 +98,13 @@ extern void warn_slowpath_null(const char *file, const int line);
})
#endif
#define WARN_TAINT(condition, taint, format...) ({ \
int __ret_warn_on = !!(condition); \
if (unlikely(__ret_warn_on)) \
__WARN_printf_taint(taint, format); \
unlikely(__ret_warn_on); \
})
#else /* !CONFIG_BUG */
#ifndef HAVE_ARCH_BUG
#define BUG() do {} while(0)
@ -110,6 +128,8 @@ extern void warn_slowpath_null(const char *file, const int line);
})
#endif
#define WARN_TAINT(condition, taint, format...) WARN_ON(condition)
#endif
#define WARN_ON_ONCE(condition) ({ \
@ -132,6 +152,16 @@ extern void warn_slowpath_null(const char *file, const int line);
unlikely(__ret_warn_once); \
})
#define WARN_TAINT_ONCE(condition, taint, format...) ({ \
static bool __warned; \
int __ret_warn_once = !!(condition); \
\
if (unlikely(__ret_warn_once)) \
if (WARN_TAINT(!__warned, taint, format)) \
__warned = true; \
unlikely(__ret_warn_once); \
})
#define WARN_ON_RATELIMIT(condition, state) \
WARN_ON((condition) && __ratelimit(state))

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@ -365,7 +365,8 @@ struct slowpath_args {
va_list args;
};
static void warn_slowpath_common(const char *file, int line, void *caller, struct slowpath_args *args)
static void warn_slowpath_common(const char *file, int line, void *caller,
unsigned taint, struct slowpath_args *args)
{
const char *board;
@ -381,7 +382,7 @@ static void warn_slowpath_common(const char *file, int line, void *caller, struc
print_modules();
dump_stack();
print_oops_end_marker();
add_taint(TAINT_WARN);
add_taint(taint);
}
void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...)
@ -390,14 +391,29 @@ void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...)
args.fmt = fmt;
va_start(args.args, fmt);
warn_slowpath_common(file, line, __builtin_return_address(0), &args);
warn_slowpath_common(file, line, __builtin_return_address(0),
TAINT_WARN, &args);
va_end(args.args);
}
EXPORT_SYMBOL(warn_slowpath_fmt);
void warn_slowpath_fmt_taint(const char *file, int line,
unsigned taint, const char *fmt, ...)
{
struct slowpath_args args;
args.fmt = fmt;
va_start(args.args, fmt);
warn_slowpath_common(file, line, __builtin_return_address(0),
taint, &args);
va_end(args.args);
}
EXPORT_SYMBOL(warn_slowpath_fmt_taint);
void warn_slowpath_null(const char *file, int line)
{
warn_slowpath_common(file, line, __builtin_return_address(0), NULL);
warn_slowpath_common(file, line, __builtin_return_address(0),
TAINT_WARN, NULL);
}
EXPORT_SYMBOL(warn_slowpath_null);
#endif

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@ -165,7 +165,7 @@ enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs)
(void *)bugaddr);
show_regs(regs);
add_taint(TAINT_WARN);
add_taint(BUG_GET_TAINT(bug));
return BUG_TRAP_TYPE_WARN;
}