From: Andi Kleen <[email protected]> Some architectures store the WARN_ONCE state in the flags field of the bug_entry. Clear that one too when resetting once state through /sys/kernel/debug/clear_warn_once
Pointed out by Michael Ellerman Improves the earlier patch that add clear_warn_once. Cc: [email protected] v2: Add a missing ifdef CONFIG_MODULES. Thanks 0day! Signed-off-by: Andi Kleen <[email protected]> --- include/linux/bug.h | 5 +++++ kernel/panic.c | 1 + lib/bug.c | 23 +++++++++++++++++++++++ 3 files changed, 29 insertions(+) diff --git a/include/linux/bug.h b/include/linux/bug.h index 5d5554c874fd..b8666ee88086 100644 --- a/include/linux/bug.h +++ b/include/linux/bug.h @@ -42,6 +42,8 @@ enum bug_trap_type report_bug(unsigned long bug_addr, struct pt_regs *regs); /* These are defined by the architecture */ int is_valid_bugaddr(unsigned long addr); +void generic_bug_clear_once(void); + #else /* !CONFIG_GENERIC_BUG */ static inline enum bug_trap_type report_bug(unsigned long bug_addr, @@ -50,6 +52,9 @@ static inline enum bug_trap_type report_bug(unsigned long bug_addr, return BUG_TRAP_TYPE_BUG; } + +static inline void generic_bug_clear_once(void) {} + #endif /* CONFIG_GENERIC_BUG */ /* diff --git a/kernel/panic.c b/kernel/panic.c index 49dbdb231a77..840a98fa4963 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -595,6 +595,7 @@ EXPORT_SYMBOL(warn_slowpath_null); static int clear_warn_once_set(void *data, u64 val) { + generic_bug_clear_once(); memset(__start_once, 0, __end_once - __start_once); return 0; } diff --git a/lib/bug.c b/lib/bug.c index a6a1137d06db..2adafcb41d5b 100644 --- a/lib/bug.c +++ b/lib/bug.c @@ -195,3 +195,26 @@ enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs) return BUG_TRAP_TYPE_BUG; } + +static void clear_once_table(struct bug_entry *start, struct bug_entry *end) +{ + struct bug_entry *bug; + + for (bug = start; bug < end; bug++) + bug->flags &= ~BUGFLAG_ONCE; +} + +void generic_bug_clear_once(void) +{ + struct module *mod; + +#ifdef CONFIG_MODULES + rcu_read_lock_sched(); + list_for_each_entry_rcu(mod, &module_bug_list, bug_list) + clear_once_table(mod->bug_table, + mod->bug_table + mod->num_bugs); + rcu_read_unlock_sched(); +#endif + + clear_once_table(__start___bug_table, __stop___bug_table); +} -- 2.13.6
