The last two days I was casing a bug related sw ringbuffer usage. Reading from an empty buffer caused my system to crash anytime later in all kinds of fashions. The crash happened at a time where no iio related function calls where going on. It appears that on my nommu development system freeing memory twice can lead to such bugs. And the fact that it does error right away made debugging this issue a pain. iio_ring_rip_outer() calls rb->access.rip_lots() which defaults in the sw ring buffer case to iio_rip_sw_rb(). iio_rip_sw_rb() returns 0 and frees the local buffer: if (initial_write_p == initial_read_p) /* No new data available.*/ or if (unlikely(initial_read_p == NULL)) /* No data here as yet */ However iio_ring_rip_outer() only checks for copied/retured < 0. It then carries on copies 0 bytes to user and frees the buffer again. -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
