On Wed, May 28, 2014 at 04:59:31PM +0100, Will Deacon wrote: > > > Can we add another of detecting whether it's an EFI application and > > > avoid calling efi_init()? I can see x86 sets some efi_loader_signature > > > string in exit_boot() and checks against it later when calling > > > efi_init(). > > > > Well, I agree that we shouldn't be spewing error messages for expected > > operation, but efi_init() is the function we call to determine > > whether we _are_ booting via UEFI - and it sets flags accordingly for > > the efi_enabled() macro. > > > > My view is that this should be fixed in fdt_find_uefi_params(). A > > single info message that we can't find evidence of UEFI should be > > printed in the non-error case. > > > > Like below? > > Why not move the efi_get_fdt_params call out of efi_init and into > setup_arch via a wrapper? Then efi_get_fdt_params and efi_init can have > useful return values, which allow us to distinguish between "My DT doesn't > have the necessary UEFI properties" and "UEFI failed to initialise" without > having to make some printks pr_info and others pr_err within efi_init > itself.. Well, but (for the output part) my patch already did that? If the "Getting parameters from FDT:\n" was too verbose, we could just drop it, and have the same effect on output. Thing is - there is not really any error case available anywhere during the execution of efi_init() and its branches other than: - Information required for UEFI boot cannot be found. - Information exists, but is invalid. - Failed to early_memremap some UEFI regions into the kernel. which all amounts to "UEFI not available or something went wrong", rather than "UEFI failed to initialise". If efi_init returns successfully, EFI_BOOT is set, and testable using the efi_enabled() macro. The proper "UEFI failed to initialise" bit does not come until the early_initcall arm64_enter_virtual_mode(), and is indicated not by a return value, but by setting the flag indicating that EFI_RUNTIME_SERVICES are available, which is checked later in core code using the efi_enabled() macro. So moving the call to efi_get_fdt_params() would have little effect other than adding a third call site for UEFI bits in setup_arch(). / Leif -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
