KAMEZAWA Hiroyuki wrote:
On Tue, 18 Aug 2009 14:31:23 +0800 Amerigo Wang <amwang@xxxxxxxxxx> wrote:Hi, thank you!Can I have a question ? - How crash kernel's memory is preserved at boot ?Use bootmem, I think.I see. In x86,setup_arch()-> reserve_crashkernel() -> find_and_reserve_crashkernel() -> reserve_bootmem_generic() Then, all "active range" is already registered and there are memmap.Not sure, but probably yes. It is reserved in setup_arch() which is before mm_init() which calls mem_init().It's hidden from the system before mem_init() ?Do you have any advice to free that reserved memory after boot? :)Let's see arch/x86/mm/init.c::free_initmem() Maybe it's all you want. - ClearPageReserved() - init_page_count() - free_page() - totalram_pages++ But it has no argumetns. Maybe you need your own function or modification. online_pages() does very similar. But, hmm,.. writing something open coded one for crashkernel is not very bad, I think.
Nice help!Yeah, I think we can make that be a generic wrapper function so that both free_initmem() and shrink_crash_memory() can use it.
Then I will update and resend the whole patchset. Thank you! -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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