From 5f79020cb9fea59a5d4d1712bcd320523b129b35 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Wed, 28 Sep 2011 12:17:03 +0100 Subject: kmemleak: Show where early_log issues come from Based on initial patch by Steven Rostedt. Early kmemleak warnings did not show where the actual kmemleak API had been called from but rather just a backtrace to the kmemleak_init() function. By having all early kmemleak logs record the stack_trace, we can have kmemleak_init() write exactly where the problem occurred. This patch adds the setting of the kmemleak_warning variable every time a kmemleak warning is issued. The kmemleak_init() function checks this variable during early log replaying and prints the log trace if there was any warning. Reported-by: Steven Rostedt Cc: Andrew Morton Signed-off-by: Catalin Marinas Acked-by: Steven Rostedt --- mm/kmemleak.c | 37 ++++++++++++++++++++++++++++--------- 1 file changed, 28 insertions(+), 9 deletions(-) (limited to 'mm/kmemleak.c') diff --git a/mm/kmemleak.c b/mm/kmemleak.c index f3b2a00fe9c1..8b528e3f8413 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -196,7 +196,9 @@ static atomic_t kmemleak_enabled = ATOMIC_INIT(0); static atomic_t kmemleak_initialized = ATOMIC_INIT(0); /* enables or disables early logging of the memory operations */ static atomic_t kmemleak_early_log = ATOMIC_INIT(1); -/* set if a fata kmemleak error has occurred */ +/* set if a kmemleak warning was issued */ +static atomic_t kmemleak_warning = ATOMIC_INIT(0); +/* set if a fatal kmemleak error has occurred */ static atomic_t kmemleak_error = ATOMIC_INIT(0); /* minimum and maximum address that may be valid pointers */ @@ -259,9 +261,10 @@ static void kmemleak_disable(void); /* * Print a warning and dump the stack trace. */ -#define kmemleak_warn(x...) do { \ - pr_warning(x); \ - dump_stack(); \ +#define kmemleak_warn(x...) do { \ + pr_warning(x); \ + dump_stack(); \ + atomic_set(&kmemleak_warning, 1); \ } while (0) /* @@ -403,8 +406,8 @@ static struct kmemleak_object *lookup_object(unsigned long ptr, int alias) object = prio_tree_entry(node, struct kmemleak_object, tree_node); if (!alias && object->pointer != ptr) { - pr_warning("Found object by alias at 0x%08lx\n", ptr); - dump_stack(); + kmemleak_warn("Found object by alias at 0x%08lx\n", + ptr); dump_object_info(object); object = NULL; } @@ -811,8 +814,7 @@ static void __init log_early(int op_type, const void *ptr, size_t size, log->ptr = ptr; log->size = size; log->min_count = min_count; - if (op_type == KMEMLEAK_ALLOC) - log->trace_len = __save_stack_trace(log->trace); + log->trace_len = __save_stack_trace(log->trace); crt_early_log++; local_irq_restore(flags); } @@ -1659,6 +1661,17 @@ static int kmemleak_boot_config(char *str) } early_param("kmemleak", kmemleak_boot_config); +static void __init print_log_trace(struct early_log *log) +{ + struct stack_trace trace; + + trace.nr_entries = log->trace_len; + trace.entries = log->trace; + + pr_notice("Early log backtrace:\n"); + print_stack_trace(&trace, 2); +} + /* * Kmemleak initialization. */ @@ -1720,7 +1733,13 @@ void __init kmemleak_init(void) kmemleak_no_scan(log->ptr); break; default: - WARN_ON(1); + kmemleak_warn("Unknown early log operation: %d\n", + log->op_type); + } + + if (atomic_read(&kmemleak_warning)) { + print_log_trace(log); + atomic_set(&kmemleak_warning, 0); } } } -- cgit v1.2.3-59-g8ed1b