On 08/01/2018 05:35 AM, Ivid Suvarna wrote:
Hi,When pstore is enabled and a *pr_info(any printk) in __memcpy_toio(arch/arm64/kernel/io.c)* is added, kernel wont boot and just hangs. The path where __memcpy_toio is called is below: ->persistent_ram_update -> memcpy_toio -> __memcpy_toio I tried with trace_printk and kernel boots fine. I understand that printk has overhead, but is this expected when we use some printk statement in __memcpy_toio?
I think the problem may be that the printk() output is copied to pstore. Since pstore calls memcpy_toio(), you get a nice recursion if you add a printk() call to it. Guenter
