On 5/27/2019 2:08 PM, Adrian Hunter wrote:
On 27/05/19 12:37 PM, Brian Masney wrote:
On Sun, May 26, 2019 at 03:58:19PM -0400, Brian Masney wrote:
I attached a patch that shows how I was able to determine what had
already claimed the host.
On Mon, May 27, 2019 at 10:48:24AM +0300, Adrian Hunter wrote:
This is because SDHCI is using the IRQ thread to process the SDIO card
interrupt (sdio_run_irqs()). When the card driver tries to use the card, it
causes interrupts which deadlocks since c07a48c26519 ("mmc: sdhci: Remove
finish_tasklet") has moved the tasklet processing to the IRQ thread.
I would expect to be able to use the IRQ thread to complete requests, and it
is desirable to do so because it is lower latency.
Probably, SDHCI should use sdio_signal_irq() which queues a work item, and
is what other drivers are doing.
I will investigate some more and send a patch.
Please try the patch below:
Finally got time to update my kernel to 5.2-rc2. This patch indeed
resolves the issue.
Thanks,
Arend