Re: [PATCH] m68k/atari - ide: do not register interrupt if host-get_lock is set
From: Michael Schmitz schmitz...@gmail.com Date: Thu, 6 Mar 2014 19:47:06 +1300 Thanks Dave, On m68k, host-get_lock is used to both lock and register the interrupt that the IDE host shares with other device drivers. Registering the IDE interrupt handler in ide-probe.c results in duplicating the interrupt registered (once via host-get lock, and also via init_irq()), and may result in IDE accepting interrupts even when another driver has locked the interrupt hardware. This opens the whole locking scheme up to races. host-get_lock is set on m68k only, so other drivers' behaviour is not changed. Signed-off-by: Michael Schmitz schm...@debian.org It's a bit kludgy, but minimal and correct. Would you have preferred to use a host flag instead? I looked into that, we are out of host flags. We'd either need to expand the flags value to 64-bits or add another u32. That's overkill for this. -- To unsubscribe from this list: send the line unsubscribe linux-m68k in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] m68k/atari - ide: do not register interrupt if host-get_lock is set
Thanks Dave, On m68k, host-get_lock is used to both lock and register the interrupt that the IDE host shares with other device drivers. Registering the IDE interrupt handler in ide-probe.c results in duplicating the interrupt registered (once via host-get lock, and also via init_irq()), and may result in IDE accepting interrupts even when another driver has locked the interrupt hardware. This opens the whole locking scheme up to races. host-get_lock is set on m68k only, so other drivers' behaviour is not changed. Signed-off-by: Michael Schmitz schm...@debian.org It's a bit kludgy, but minimal and correct. Would you have preferred to use a host flag instead? Applied, thank you. Thanks again, Michael -- To unsubscribe from this list: send the line unsubscribe linux-m68k in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] m68k/atari - ide: do not register interrupt if host-get_lock is set
From: Michael Schmitz schmitz...@gmail.com Date: Sat, 1 Feb 2014 13:48:13 +1300 On m68k, host-get_lock is used to both lock and register the interrupt that the IDE host shares with other device drivers. Registering the IDE interrupt handler in ide-probe.c results in duplicating the interrupt registered (once via host-get lock, and also via init_irq()), and may result in IDE accepting interrupts even when another driver has locked the interrupt hardware. This opens the whole locking scheme up to races. host-get_lock is set on m68k only, so other drivers' behaviour is not changed. Signed-off-by: Michael Schmitz schm...@debian.org It's a bit kludgy, but minimal and correct. Applied, thank you. -- To unsubscribe from this list: send the line unsubscribe linux-m68k in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] m68k/atari - ide: do not register interrupt if host-get_lock is set
On Tue, Jan 28, 2014 at 9:07 AM, Michael Schmitz schmitz...@gmail.com wrote:
--- a/drivers/ide/ide-probe.c
+++ b/drivers/ide/ide-probe.c
@@ -853,8 +853,9 @@ static int init_irq (ide_hwif_t *hwif)
if (irq_handler == NULL)
irq_handler = ide_intr;
- if (request_irq(hwif-irq, irq_handler, sa, hwif-name, hwif))
- goto out_up;
+ if (!host-get_lock)
+ if (request_irq(hwif-irq, irq_handler, sa, hwif-name, hwif))
+ goto out_up;
Don't you need a similar check for free_irq()?
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say programmer or something like that.
-- Linus Torvalds
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Re: [PATCH] m68k/atari - ide: do not register interrupt if host-get_lock is set
Geert, On Fri, Jan 31, 2014 at 4:03 AM, Geert Uytterhoeven ge...@linux-m68k.org wrote: On Tue, Jan 28, 2014 at 9:07 AM, Michael Schmitz schmitz...@gmail.com wrote: --- a/drivers/ide/ide-probe.c +++ b/drivers/ide/ide-probe.c @@ -853,8 +853,9 @@ static int init_irq (ide_hwif_t *hwif) if (irq_handler == NULL) irq_handler = ide_intr; - if (request_irq(hwif-irq, irq_handler, sa, hwif-name, hwif)) - goto out_up; + if (!host-get_lock) + if (request_irq(hwif-irq, irq_handler, sa, hwif-name, hwif)) + goto out_up; Don't you need a similar check for free_irq()? Absolutely. Thanks for spotting this. I'll send the fixed version to linux-ide. Cheers, Michael -- To unsubscribe from this list: send the line unsubscribe linux-m68k in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
