On 30 May 2011 16:38, Nicolas Pitre <nicolas.pitre@xxxxxxxxxx> wrote: > On Mon, 30 May 2011, Per Forlin wrote: > >> Hi Daniel, >> >> > >> > On 29 May 2011 15:26, Daniel Drake <dsd <at> laptop.org> wrote: >> > > Hi, >> > > >> > > The following commit in 2.6.39 causes instant death for libertas_sdio >> > > when it receives its first interrupt during initialization: >> > > >> > > commit 06e8935febe687e2a561707d4c7ca4245d261dbe >> > >> > The crash happens on this line of code in if_sdio_interrupt: >> > >> > cause = sdio_readb(card->func, IF_SDIO_H_INT_STATUS, &ret); >> > >> > card is NULL here >> Thanks for you detailed report. It fails due to sdio_get_drvdata() returns NULL. >> >> I am thinking of if the timing has changed due to this "single irq" patch or if >> the functionality is broken. >> To answer that I have a question on the if_sdio.c in libertas. >> >> if_sdio.c >> sdio_claim_host(); >> sdio_claim_irq() >> ... >> sdio_release_host() >> sdio_set_drvdata(func, card) > > This looks wrong to me. the driver must be ready to receive interrupts > the moment it registers for it, or make sure the hardware is not > generating any. > >> Just a sanity question, can the interrupt occur before sdio_set_drvdata()? > > What might be happening here is that for some reasons the card is > asserting the interrupt line, but none of the function bits in CCCR_INTx > is set. > I think your assumption is correct. I didn't know this could happen. I propose to let the client decide whether use make sdio_irq_single or not, default is no. I'll make patch for it. Thanks, Per -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
