From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> [ Upstream commit 51fbf14f2528a8c6401290e37f1c893a2412f1d3 ] The only use of KEXEC_BACKUP_SRC_END is as an argument to walk_system_ram_res(): int crash_load_segments(struct kimage *image) { ... walk_system_ram_res(KEXEC_BACKUP_SRC_START, KEXEC_BACKUP_SRC_END, image, determine_backup_region); walk_system_ram_res() expects "start, end" arguments that are inclusive, i.e., the range to be walked includes both the start and end addresses. KEXEC_BACKUP_SRC_END was previously defined as (640 * 1024UL), which is the first address *past* the desired 0-640KB range. Define KEXEC_BACKUP_SRC_END as (640 * 1024UL - 1) so the KEXEC_BACKUP_SRC region is [0-0x9ffff], not [0-0xa0000]. Fixes: dd5f726076cc ("kexec: support for kexec on panic using new system call") Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> CC: "H. Peter Anvin" <hpa@xxxxxxxxx> CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> CC: Brijesh Singh <brijesh.singh@xxxxxxx> CC: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> CC: Ingo Molnar <mingo@xxxxxxxxxx> CC: Lianbo Jiang <lijiang@xxxxxxxxxx> CC: Takashi Iwai <tiwai@xxxxxxx> CC: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CC: Tom Lendacky <thomas.lendacky@xxxxxxx> CC: Vivek Goyal <vgoyal@xxxxxxxxxx> CC: baiyaowei@xxxxxxxxxxxxxxxxxxxx CC: bhe@xxxxxxxxxx CC: dan.j.williams@xxxxxxxxx CC: dyoung@xxxxxxxxxx CC: kexec@xxxxxxxxxxxxxxxxxxx Link: http://lkml.kernel.org/r/153805811578.1157.6948388946904655969.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/x86/include/asm/kexec.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h index 282630e4c6ea4..1624a7ffa95d8 100644 --- a/arch/x86/include/asm/kexec.h +++ b/arch/x86/include/asm/kexec.h @@ -66,7 +66,7 @@ struct kimage; /* Memory to backup during crash kdump */ #define KEXEC_BACKUP_SRC_START (0UL) -#define KEXEC_BACKUP_SRC_END (640 * 1024UL) /* 640K */ +#define KEXEC_BACKUP_SRC_END (640 * 1024UL - 1) /* 640K */ /* * CPU does not save ss and sp on stack if execution is already -- 2.20.1