From 9d2f86c6cad5a8a3f0b38a80136ba68364ca7278 Mon Sep 17 00:00:00 2001 From: Alex Thorlton Date: Mon, 5 Dec 2016 11:49:13 -0600 Subject: [PATCH] x86: Make E820_X_MAX unconditionally larger than E820MAX It's really not necessary to limit E820_X_MAX to 128 in the non-EFI case. This commit drops E820_X_MAX's dependency on CONFIG_EFI, so that E820_X_MAX is always at least slightly larger than E820MAX. The real motivation behind this is actually to prevent some issues in the Xen kernel, where the XENMEM_machine_memory_map hypercall can produce an e820 map larger than 128 entries, even on systems where the original e820 table was quite a bit smaller than that, depending on how many IOAPICs are installed on the system. Signed-off-by: Alex Thorlton Suggested-by: Ingo Molnar Acked-by: Ingo Molnar Signed-off-by: Juergen Gross --- arch/x86/include/asm/e820.h | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/e820.h b/arch/x86/include/asm/e820.h index 476b574..ec23d8e 100644 --- a/arch/x86/include/asm/e820.h +++ b/arch/x86/include/asm/e820.h @@ -1,13 +1,17 @@ #ifndef _ASM_X86_E820_H #define _ASM_X86_E820_H -#ifdef CONFIG_EFI +/* + * E820_X_MAX is the maximum size of the extended E820 table. The extended + * table may contain up to 3 extra E820 entries per possible NUMA node, so we + * make room for 3 * MAX_NUMNODES possible entries, beyond the standard 128. + * Also note that E820_X_MAX *must* be defined before we include uapi/asm/e820.h. + */ #include #define E820_X_MAX (E820MAX + 3 * MAX_NUMNODES) -#else /* ! CONFIG_EFI */ -#define E820_X_MAX E820MAX -#endif + #include + #ifndef __ASSEMBLY__ /* see comment in arch/x86/kernel/e820.c */ extern struct e820map *e820; -- 2.7.4