diff options
| -rw-r--r-- | drivers/tty/serial/8250.c | 13 | ||||
| -rw-r--r-- | include/linux/kdb.h | 2 | ||||
| -rw-r--r-- | kernel/debug/kdb/kdb_io.c | 6 |
3 files changed, 13 insertions, 8 deletions
diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c index a762f122acb2..b89144ee37ef 100644 --- a/drivers/tty/serial/8250.c +++ b/drivers/tty/serial/8250.c @@ -38,6 +38,7 @@ #include <linux/nmi.h> #include <linux/mutex.h> #include <linux/slab.h> +#include <linux/kdb.h> #include <asm/io.h> #include <asm/irq.h> @@ -2896,10 +2897,14 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count) touch_nmi_watchdog(); - if (up->port.sysrq || oops_in_progress) - locked = spin_trylock_irqsave(&up->port.lock, flags); - else - spin_lock_irqsave(&up->port.lock, flags); + if (unlikely(in_kdb_printk())) { + locked = 0; + } else { + if (up->port.sysrq || oops_in_progress) + locked = spin_trylock_irqsave(&up->port.lock, flags); + else + spin_lock_irqsave(&up->port.lock, flags); + } /* * First save the IER then disable the interrupts diff --git a/include/linux/kdb.h b/include/linux/kdb.h index aadff7cc2b84..18d20dd2071d 100644 --- a/include/linux/kdb.h +++ b/include/linux/kdb.h @@ -153,12 +153,14 @@ extern int kdb_register(char *, kdb_func_t, char *, char *, short); extern int kdb_register_repeat(char *, kdb_func_t, char *, char *, short, kdb_repeat_t); extern int kdb_unregister(char *); +#define in_kdb_printk() (kdb_trap_printk) #else /* ! CONFIG_KGDB_KDB */ #define kdb_printf(...) #define kdb_init(x) #define kdb_register(...) #define kdb_register_repeat(...) #define kdb_uregister(x) +#define in_kdb_printk() (0) #endif /* CONFIG_KGDB_KDB */ enum { KDB_NOT_INITIALIZED, diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c index 96fdaac46a80..ffd5eb2342ed 100644 --- a/kernel/debug/kdb/kdb_io.c +++ b/kernel/debug/kdb/kdb_io.c @@ -539,7 +539,6 @@ int vkdb_printf(const char *fmt, va_list ap) int diag; int linecount; int logging, saved_loglevel = 0; - int saved_trap_printk; int got_printf_lock = 0; int retlen = 0; int fnd, len; @@ -550,8 +549,6 @@ int vkdb_printf(const char *fmt, va_list ap) unsigned long uninitialized_var(flags); preempt_disable(); - saved_trap_printk = kdb_trap_printk; - kdb_trap_printk = 0; /* Serialize kdb_printf if multiple cpus try to write at once. * But if any cpu goes recursive in kdb, just print the output, @@ -807,7 +804,6 @@ kdb_print_out: } else { __release(kdb_printf_lock); } - kdb_trap_printk = saved_trap_printk; preempt_enable(); return retlen; } @@ -817,9 +813,11 @@ int kdb_printf(const char *fmt, ...) va_list ap; int r; + kdb_trap_printk++; va_start(ap, fmt); r = vkdb_printf(fmt, ap); va_end(ap); + kdb_trap_printk--; return r; } |