forked from Minki/linux
8250.c: port.lock is irq-safe
serial8250_startup() doesn't disable interrupts while taking the &up->port.lock which might race against the interrupt handler serial8250_interrupt(), which when entered, will deadlock waiting for the lock to be released. Signed-off-by: Borislav Petkov <petkovbb@gmail.com> Tested-by: Ingo Molnar <mingo@elte.hu> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
5def9a3a22
commit
c389d27b5e
@ -1885,7 +1885,7 @@ static int serial8250_startup(struct uart_port *port)
|
||||
* the interrupt is enabled. Delays are necessary to
|
||||
* allow register changes to become visible.
|
||||
*/
|
||||
spin_lock(&up->port.lock);
|
||||
spin_lock_irqsave(&up->port.lock, flags);
|
||||
if (up->port.flags & UPF_SHARE_IRQ)
|
||||
disable_irq_nosync(up->port.irq);
|
||||
|
||||
@ -1901,7 +1901,7 @@ static int serial8250_startup(struct uart_port *port)
|
||||
|
||||
if (up->port.flags & UPF_SHARE_IRQ)
|
||||
enable_irq(up->port.irq);
|
||||
spin_unlock(&up->port.lock);
|
||||
spin_unlock_irqrestore(&up->port.lock, flags);
|
||||
|
||||
/*
|
||||
* If the interrupt is not reasserted, setup a timer to
|
||||
|
Loading…
Reference in New Issue
Block a user