From 917a35605f09c0d16aeb2e92c7fbff562e19a116 Mon Sep 17 00:00:00 2001 From: Minfei Huang Date: Mon, 23 May 2016 16:24:16 -0700 Subject: [PATCH] kexec: make a pair of map/unmap reserved pages in error path For some arch, kexec shall map the reserved pages, then use them, when we try to start the kdump service. kexec may return directly, without unmaping the reserved pages, if it fails during starting service. To fix it, we make a pair of map/unmap reserved pages both in generic path and error path. This patch only affects s390. Other architecturess don't implement the interface of crash_unmap_reserved_pages and crash_map_reserved_pages. It isn't a urgent patch. Kernel can work well without any risk, although the reserved pages are not unmapped before returning in error path. Signed-off-by: Minfei Huang Cc: Vivek Goyal Cc: "Eric W. Biederman" Cc: Xunlei Pang Cc: Baoquan He Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/kexec.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/kernel/kexec.c b/kernel/kexec.c index b44cb3f5a15c..4b49aa71304f 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -194,22 +194,25 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments, segments, flags); } if (result) - goto out; + goto unmap_page; if (flags & KEXEC_PRESERVE_CONTEXT) image->preserve_context = 1; result = machine_kexec_prepare(image); if (result) - goto out; + goto unmap_page; for (i = 0; i < nr_segments; i++) { result = kimage_load_segment(image, &image->segment[i]); if (result) - goto out; + goto unmap_page; } kimage_terminate(image); +unmap_page: if (flags & KEXEC_ON_CRASH) crash_unmap_reserved_pages(); + if (result) + goto out; } /* Install the new kernel, and Uninstall the old */ image = xchg(dest_image, image); -- 2.20.1