summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorBaoquan He <bhe@redhat.com>2015-09-09 15:39:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-09-10 13:29:01 -0700
commit1303a27c9c32020a3b6ac89be270d2ab1f28be24 (patch)
treed94da15d2e4eea4012ae69a4e19da6827b6deed6
parentbbb78b8f3f4ea8eca14937b693bfe244838e1d4d (diff)
downloadlinux-1303a27c9c32020a3b6ac89be270d2ab1f28be24.tar.gz
linux-1303a27c9c32020a3b6ac89be270d2ab1f28be24.tar.bz2
linux-1303a27c9c32020a3b6ac89be270d2ab1f28be24.zip
kexec: export KERNEL_IMAGE_SIZE to vmcoreinfo
In x86_64, since v2.6.26 the KERNEL_IMAGE_SIZE is changed to 512M, and accordingly the MODULES_VADDR is changed to 0xffffffffa0000000. However, in v3.12 Kees Cook introduced kaslr to randomise the location of kernel. And the kernel text mapping addr space is enlarged from 512M to 1G. That means now KERNEL_IMAGE_SIZE is variable, its value is 512M when kaslr support is not compiled in and 1G when kaslr support is compiled in. Accordingly the MODULES_VADDR is changed too to be: #define MODULES_VADDR (__START_KERNEL_map + KERNEL_IMAGE_SIZE) So when kaslr is compiled in and enabled, the kernel text mapping addr space and modules vaddr space need be adjusted. Otherwise makedumpfile will collapse since the addr for some symbols is not correct. Hence KERNEL_IMAGE_SIZE need be exported to vmcoreinfo and got in makedumpfile to help calculate MODULES_VADDR. Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--kernel/kexec_core.c3
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index 322dd5579f59..201b45327804 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -1417,6 +1417,9 @@ static int __init crash_save_vmcoreinfo_init(void)
#endif
VMCOREINFO_NUMBER(PG_head_mask);
VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
+#ifdef CONFIG_X86
+ VMCOREINFO_NUMBER(KERNEL_IMAGE_SIZE);
+#endif
#ifdef CONFIG_HUGETLBFS
VMCOREINFO_SYMBOL(free_huge_page);
#endif