On 02/28/2018 06:38 AM, Bartosz Golaszewski wrote:
I think I found the reason for the strange crashes we were experiencing (emac core->name being NULL) thanks to Sekhar who pointed me in the right direction. The mdio driver fails to probe with v7 due to the supplied clock rate being wrong. Before failing we register the emac clock with pm_clk_add_clk(). When clock_ops puts the clock, it decreases the reference count of the clock, but we never actually increased it in the first place in the line above. The core clock code then destroys the associated clk_core structure. When the next user comes around (in our case the clk debug functions) the system crashes. I believe there to be two issues: one is with v7 - we need to increase the clock reference count in davinci_psc_genpd_attach_dev(). Second is the error path in the clock framework - we should remove the destroyed clk_core from the debug list, which is not being done now. Why we even need to track the refcount of clk_core is a mistery for me though. Stephen, Mike? Best regards, Bartosz Golaszewski
Great find. I figured it had to be something like this, but I wasn't able to reproduce the problem yet. I suppose it is time to spin up a v8 with some fixes. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
