On Thu, May 12, 2016 at 02:26:27PM +0800, Baoquan He wrote:

On 04/28/16 at 10:28am, Russell King wrote:

quoted

diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 52a3a221bcb2..99cb9dac7909 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h

@@ -318,6 +318,44 @@ int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr,
 int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 					unsigned int relsec);
 
+#ifndef page_to_boot_pfn
+static inline unsigned long page_to_boot_pfn(struct page *page)
+{
+	return page_to_pfn(page);
+}
+#endif

I am thinking if it's appropriate to introduce a new concept which only
exists in a certain system of a certain ARCH. Is it unavoidable? If have
to can we name it as kexec_page_to_pfn/kexec_pfn_to_page, etc? People
might not need to know about boot view physical address and kernel view
physical address things when they just want to understand kexec
implementation related to one ARCH except of ARM, even related to ARM
but not Keystone 2.

Well, what do you suggest we do instead?

Eric, please get involved in this discussion, as this was your idea.

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