diff options
| author | Finn Thain <fthain@telegraphics.com.au> | 2018-12-01 11:53:10 +1100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-01-29 10:21:50 +0100 |
| commit | eb0d764eb0f5663b1d93935a72c29c496ec4f5cc (patch) | |
| tree | 8b9b9ee2a83f284af73e093a3939c1133ccd2257 /arch/m68k/q40 | |
| parent | 0f8e73eb058750c8cd38be8cbfa048d71c7e2ec5 (diff) | |
m68k: Call timer_interrupt() with interrupts disabled
[ Upstream commit 1efdd4bd254311498123a15fa0acd565f454da97 ]
Some platforms execute their timer handler with the interrupt priority
level set below 6. That means the handler could be interrupted by another
driver and this could lead to re-entry of the timer core.
Avoid this by use of local_irq_save/restore for timer interrupt dispatch.
This provides mutual exclusion around the timer interrupt flag access
which is needed later in this series for the clocksource conversion.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/alpine.DEB.2.21.1811131407120.2697@nanos.tec.linutronix.de
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch/m68k/q40')
| -rw-r--r-- | arch/m68k/q40/q40ints.c | 19 |
1 files changed, 11 insertions, 8 deletions
diff --git a/arch/m68k/q40/q40ints.c b/arch/m68k/q40/q40ints.c index 513f9bb17b9c..60b51f5b9cfc 100644 --- a/arch/m68k/q40/q40ints.c +++ b/arch/m68k/q40/q40ints.c @@ -126,10 +126,10 @@ void q40_mksound(unsigned int hz, unsigned int ticks) sound_ticks = ticks << 1; } -static irq_handler_t q40_timer_routine; - -static irqreturn_t q40_timer_int (int irq, void * dev) +static irqreturn_t q40_timer_int(int irq, void *dev_id) { + irq_handler_t timer_routine = dev_id; + ql_ticks = ql_ticks ? 0 : 1; if (sound_ticks) { unsigned char sval=(sound_ticks & 1) ? 128-SVOL : 128+SVOL; @@ -138,8 +138,13 @@ static irqreturn_t q40_timer_int (int irq, void * dev) *DAC_RIGHT=sval; } - if (!ql_ticks) - q40_timer_routine(irq, dev); + if (!ql_ticks) { + unsigned long flags; + + local_irq_save(flags); + timer_routine(0, NULL); + local_irq_restore(flags); + } return IRQ_HANDLED; } @@ -147,11 +152,9 @@ void q40_sched_init (irq_handler_t timer_routine) { int timer_irq; - q40_timer_routine = timer_routine; timer_irq = Q40_IRQ_FRAME; - if (request_irq(timer_irq, q40_timer_int, 0, - "timer", q40_timer_int)) + if (request_irq(timer_irq, q40_timer_int, 0, "timer", timer_routine)) panic("Couldn't register timer int"); master_outb(-1, FRAME_CLEAR_REG); |