From 96e70f83285676d8794f62f3c294d0247bef6b21 Mon Sep 17 00:00:00 2001 From: Minfei Huang Date: Thu, 23 Oct 2014 23:36:17 +0800 Subject: [PATCH] x86/mm: Avoid overlap the fixmap area on i386 It is a problem when configuring high memory off where the vmalloc reserve area could end up overlapping the early_ioremap fixmap area on i386. The ordering of the VMALLOC_RESERVE space is: FIXADDR_TOP fixed_addresses FIXADDR_START early_ioremap fixed addresses FIXADDR_BOOT_START Persistent kmap area PKMAP_BASE VMALLOC_END Vmalloc area VMALLOC_START high_memory The available address we can use is lower than FIXADDR_BOOT_START. So we will set the kmap boundary below the FIXADDR_BOOT_START, if we configure high memory. If we configure high memory, the vmalloc reserve area should end up to PKMAP_BASE, otherwise should end up to FIXADDR_BOOT_START. Signed-off-by: Minfei Huang Acked-by: Thomas Gleixner Cc: Linus Torvalds Link: http://lkml.kernel.org/r/6B680A9E-6CE9-4C96-934B-CB01DCB58278@gmail.com Signed-off-by: Ingo Molnar --- arch/x86/include/asm/pgtable_32_types.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/pgtable_32_types.h b/arch/x86/include/asm/pgtable_32_types.h index ed5903be26fe..2ac5fc86abb3 100644 --- a/arch/x86/include/asm/pgtable_32_types.h +++ b/arch/x86/include/asm/pgtable_32_types.h @@ -43,7 +43,7 @@ extern bool __vmalloc_start_set; /* set once high_memory is set */ #ifdef CONFIG_HIGHMEM # define VMALLOC_END (PKMAP_BASE - 2 * PAGE_SIZE) #else -# define VMALLOC_END (FIXADDR_START - 2 * PAGE_SIZE) +# define VMALLOC_END (FIXADDR_BOOT_START - 2 * PAGE_SIZE) #endif #define MODULES_VADDR VMALLOC_START -- 2.20.1