On 10/20/2014 02:27 PM, Stephen Boyd wrote: > On 10/17/2014 06:13 AM, Kumar Gala wrote: >> With CONFIG_DEBUG_SPINLOCK enabled we see: >> >> BUG: spinlock bad magic on CPU#0, swapper/0 >> lock: early_console_dev+0x8/0x160, .magic: 00000000, .owner: <none>/-1, >> .owner_cpu: 0 >> CPU: 0 PID: 0 Comm: swapper Not tainted 3.17.0-09733-gb446b33-dirty #18 > > [...] > >> diff --git a/drivers/tty/serial/msm_serial.c >> b/drivers/tty/serial/msm_serial.c >> index 4b6c783..8ab27c9 100644 >> --- a/drivers/tty/serial/msm_serial.c >> +++ b/drivers/tty/serial/msm_serial.c >> @@ -973,6 +973,8 @@ msm_serial_early_console_setup(struct earlycon_device >> *device, const char *opt) >> if (!device->port.membase) >> return -ENODEV; >> + spin_lock_init(&device->port.lock); >> + >> device->con->write = msm_serial_early_write; >> return 0; >> } >> @@ -995,6 +997,8 @@ msm_serial_early_console_setup_dm(struct earlycon_device >> *device, >> if (!device->port.membase) >> return -ENODEV; >> + spin_lock_init(&device->port.lock); >> + >> device->con->write = msm_serial_early_write_dm; >> return 0; >> } > > Could this be done in the tty core instead?
Or even better: refactor __msm_console_write() so no spin_lock() is required for the earlycon write. FWIW, __msm_console_write() is a deadlock-waiting-to_happen since it does not disable interrupts with spin_lock_irqsave(). Regards, Peter Hurley -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
