From: Jeremy Fitzhardinge Date: Wed, 13 Oct 2010 23:34:15 +0000 (-0700) Subject: x86-64: Only set max_pfn_mapped to 512 MiB if we enter via head_64.S X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=67e87f0a1c5cbc750f81ebf6a128e8ff6f4376cc;p=openwrt%2Fstaging%2Fblogic.git x86-64: Only set max_pfn_mapped to 512 MiB if we enter via head_64.S head_64.S maps up to 512 MiB, but that is not necessarity true for other entry paths, such as Xen. Thus, co-locate the setting of max_pfn_mapped with the code to actually set up the page tables in head_64.S. The 32-bit code is already so co-located. (The Xen code already sets max_pfn_mapped correctly for its own use case.) -v2: Yinghai fixed the following bug in this patch: | | max_pfn_mapped is in .bss section, so we need to set that | after bss get cleared. Without that we crash on bootup. | | That is safe because Xen does not call x86_64_start_kernel(). | Signed-off-by: Jeremy Fitzhardinge Fixed-by: Yinghai Lu Signed-off-by: H. Peter Anvin LKML-Reference: <4CB6AB24.9020504@kernel.org> Signed-off-by: Ingo Molnar --- diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 97adf9828b95..2d2673c28aff 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -80,6 +80,8 @@ void __init x86_64_start_kernel(char * real_mode_data) /* Cleanup the over mapped high alias */ cleanup_highmap(); + max_pfn_mapped = KERNEL_IMAGE_SIZE >> PAGE_SHIFT; + for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) { #ifdef CONFIG_EARLY_PRINTK set_intr_gate(i, &early_idt_handlers[i]); diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index b11a238b2e35..c3cebfe7bfc9 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -932,7 +932,6 @@ void __init setup_arch(char **cmdline_p) max_low_pfn = max_pfn; high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; - max_pfn_mapped = KERNEL_IMAGE_SIZE >> PAGE_SHIFT; #endif /*