On 07/09/2017 02:55 PM, Andreas Färber wrote: > Am 06.07.2017 um 19:17 schrieb Andreas Färber: >> Am 05.07.2017 um 04:36 schrieb Florian Fainelli: >>> On July 4, 2017 4:32:18 PM PDT, "Andreas Färber" <afaer...@suse.de> wrote: >>>> - writel(virt_to_phys(owl_secondary_startup), >>>> + writel(virt_to_phys(secondary_startup), >>>> timer_base_addr + OWL_CPU1_ADDR + (cpu - 1) * 4); >>> >>> This is a kernel symbol so please use __pa_symbol() here, also you might >>> want to build with CONFIG_DEBUG_VIRTUAL and see if you get other warnings >>> about using virt_to_phys() in the owl platform code (I did not check if >>> there are other uses) > > Florian, I don't spot any build or runtime warning for this > virt_to_phys() with CONFIG_DEBUG_VIRTUAL=y on Guitar/S500:
You would only see run time warnings, not build time warnings for this, but in fact, no, see below. > > [ 0.062765] CPU: Testing write buffer coherency: ok > [ 0.063468] CPU0: thread -1, cpu 0, socket 0, mpidr 80000000 > [ 0.100856] Setting up static identity map for 0x100000 - 0x100060 > [ 0.120864] Hierarchical SRCU implementation. > [ 0.161092] smp: Bringing up secondary CPUs ... > [ 0.291654] CPU1: thread -1, cpu 1, socket 0, mpidr 80000001 > [ 0.422226] CPU2: thread -1, cpu 2, socket 0, mpidr 80000002 > [ 0.552798] CPU3: thread -1, cpu 3, socket 0, mpidr 80000003 > [ 0.553074] smp: Brought up 1 node, 4 CPUs > [ 0.553388] SMP: Total of 4 processors activated (1629.38 BogoMIPS). > [ 0.553477] CPU: All CPU(s) started in SVC mode. > > I've tested that __pa_symbol() works as well, but I'd like to understand > this for commit message and future testing. Am I missing other options? After re-checking the implementation you would get a warning only if you were using virt_to_phys() against a part of the kernel that is not in the linear map, similarly you would get a warning if __pa_symbol() was used against symbols outside of the kernel image, this is obviously not the case here. You should use __pa_symbol() just for correctness, no warning would be produced, sorry for misleading you with that. -- Florian
