From e7706fc691513b0f06adb3de3d6ac04293180146 Mon Sep 17 00:00:00 2001 From: Ken'ichi Ohmichi Date: Mon, 20 Oct 2008 13:51:52 +0900 Subject: [PATCH] x86, kdump: fix invalid access on i386 sparsemem Impact: fix kdump crash on 32-bit sparsemem kernels Since linux-2.6.27, kdump has failed on i386 sparsemem kernel. 1st-kernel gets a panic just before switching to 2nd-kernel. The cause is that a kernel accesses invalid mem_section by page_to_pfn(image->swap_page) at machine_kexec(). image->swap_page is allocated if kexec for hibernation, but it is not allocated if kdump. So if kdump, a kernel should not access the mem_section corresponding to image->swap_page. The attached patch fixes this invalid access. Signed-off-by: Ken'ichi Ohmichi Cc: kexec-ml Cc: Andrew Morton Signed-off-by: Ingo Molnar --- arch/x86/kernel/machine_kexec_32.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/machine_kexec_32.c b/arch/x86/kernel/machine_kexec_32.c index 0732adba05ca..7a385746509a 100644 --- a/arch/x86/kernel/machine_kexec_32.c +++ b/arch/x86/kernel/machine_kexec_32.c @@ -162,7 +162,10 @@ void machine_kexec(struct kimage *image) page_list[VA_PTE_0] = (unsigned long)kexec_pte0; page_list[PA_PTE_1] = __pa(kexec_pte1); page_list[VA_PTE_1] = (unsigned long)kexec_pte1; - page_list[PA_SWAP_PAGE] = (page_to_pfn(image->swap_page) << PAGE_SHIFT); + + if (image->type == KEXEC_TYPE_DEFAULT) + page_list[PA_SWAP_PAGE] = (page_to_pfn(image->swap_page) + << PAGE_SHIFT); /* The segment registers are funny things, they have both a * visible and an invisible part. Whenever the visible part is