From 8ff80fbe7e9870078b1cc3c2cdd8f3f223b333a9 Mon Sep 17 00:00:00 2001 From: Baoquan He Date: Fri, 24 May 2019 15:38:10 +0800 Subject: x86/kdump/64: Restrict kdump kernel reservation to <64TB Restrict kdump to only reserve crashkernel below 64TB. The reaons is that the kdump may jump from a 5-level paging mode to a 4-level paging mode kernel. If a 4-level paging mode kdump kernel is put above 64TB, then the kdump kernel cannot start. The 1st kernel reserves the kdump kernel region during bootup. At that point it is not known whether the kdump kernel has 5-level or 4-level paging support. To support both restrict the kdump kernel reservation to the lower 64TB address space to ensure that a 4-level paging mode kdump kernel can be loaded and successfully started. [ tglx: Massaged changelog ] Signed-off-by: Baoquan He Signed-off-by: Thomas Gleixner Acked-by: Kirill A. Shutemov Acked-by: Dave Young Cc: bp@alien8.de Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20190524073810.24298-4-bhe@redhat.com --- include/linux/sizes.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/sizes.h') diff --git a/include/linux/sizes.h b/include/linux/sizes.h index fbde0bc7e882..8651269cb46c 100644 --- a/include/linux/sizes.h +++ b/include/linux/sizes.h @@ -47,5 +47,6 @@ #define SZ_2G 0x80000000 #define SZ_4G _AC(0x100000000, ULL) +#define SZ_64T _AC(0x400000000000, ULL) #endif /* __LINUX_SIZES_H__ */ -- cgit v1.2.3-58-ga151