Re: [Xenomai-help] System hangs in/after rtdm_lock_put_irqrestore

[Jan Kiszka <jan.kiszka@domain.hid>]

[-- Attachment #1: Type: text/plain, Size: 1038 bytes --]

Axel Beierlein wrote:
> what could it be that an simple rt_dev_open locks up my system when it  
> calls rtdm_lock_put_irqrestore?
> 
> [...]
> if (rtdm_irq_request(&ctx->irq_handle,
> 		        MPC5xxx_PSC2_IRQ,
> 			rt_psc_interrupt,
> 			RTDM_IRQTYPE_SHARED | RTDM_IRQTYPE_EDGE,
> 				context->device->proc_name,
> 				ctx))
> 	{
> 		printk ("psc5200B.c: request_irq() failed\n");
> 		return -1;
> 	}
> 
>      rtdm_irq_enable(&ctx->irq_handle);
> 
>      rtdm_lock_get_irqsave(&ctx->lock, lock_ctx);
> 
>      ctx->imr_status = MPC5xxx_PSC_IMR_RXRDY;
> 	out_be16(&psc->mpc5xxx_psc_imr, ctx->imr_status);

Let me guess: this line arms the related IRQ source at hw level, no?

> 
> 	rtdm_lock_put_irqrestore(&ctx->lock, lock_ctx);
> 	^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> 	Here i get the crash

Because it enabled local IRQ delivery again, and the system ends up in
an IRQ storm, or some endless loop in the IRQ handler, or some crash
related to IRQ handling. Still just guessing...

Jan


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 250 bytes --]