diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2013-01-08 20:36:51 (GMT) |
|---|---|---|
| committer | Scott Wood <scottwood@freescale.com> | 2014-05-14 18:38:32 (GMT) |
| commit | 54be58559963236f085fb1494e2ef6c861a9e074 (patch) | |
| tree | c96a554b1b09fbcc4708baebf9d4da4a8b13673c /drivers/tty | |
| parent | 8c6bc02edd9dfedf56ae65b75a7828214a53e986 (diff) | |
| download | linux-fsl-qoriq-54be58559963236f085fb1494e2ef6c861a9e074.tar.xz | |
drivers-tty-pl011-irq-disable-madness.patch
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/amba-pl011.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 1440d0b..729198c 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -1916,13 +1916,19 @@ pl011_console_write(struct console *co, const char *s, unsigned int count) clk_enable(uap->clk); - local_irq_save(flags); + /* + * local_irq_save(flags); + * + * This local_irq_save() is nonsense. If we come in via sysrq + * handling then interrupts are already disabled. Aside of + * that the port.sysrq check is racy on SMP regardless. + */ if (uap->port.sysrq) locked = 0; else if (oops_in_progress) - locked = spin_trylock(&uap->port.lock); + locked = spin_trylock_irqsave(&uap->port.lock, flags); else - spin_lock(&uap->port.lock); + spin_lock_irqsave(&uap->port.lock, flags); /* * First save the CR then disable the interrupts @@ -1944,8 +1950,7 @@ pl011_console_write(struct console *co, const char *s, unsigned int count) writew(old_cr, uap->port.membase + UART011_CR); if (locked) - spin_unlock(&uap->port.lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&uap->port.lock, flags); clk_disable(uap->clk); } |