kexec: add machine_kexec_post_load()

It is the same as machine_kexec_prepare(), but is called after segments are
loaded. This way, can do processing work with already loaded relocation
segments. One such example is arm64: it has to have segments loaded in
order to create a page table, but it cannot do it during kexec time,
because at that time allocations won't be possible anymore.

Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/kernel/kexec.c b/kernel/kexec.c
index bc933c0..f977786 100644 (file)
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -159,6 +159,10 @@ static int do_kexec_load(unsigned long entry, unsigned long nr_segments,
 
        kimage_terminate(image);
 
+       ret = machine_kexec_post_load(image);
+       if (ret)
+               goto out;
+
        /* Install the new kernel and uninstall the old */
        image = xchg(dest_image, image);
 

diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index f7ae04b..c19c0da 100644 (file)
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -589,6 +589,12 @@ static void kimage_free_extra_pages(struct kimage *image)
        kimage_free_page_list(&image->unusable_pages);
 
 }
+
+int __weak machine_kexec_post_load(struct kimage *image)
+{
+       return 0;
+}
+
 void kimage_terminate(struct kimage *image)
 {
        if (*image->entry != 0)

diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index a2df939..faa74d5 100644 (file)
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -441,6 +441,10 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
 
        kimage_terminate(image);
 
+       ret = machine_kexec_post_load(image);
+       if (ret)
+               goto out;
+
        /*
         * Free up any temporary buffers allocated which are not needed
         * after image has been loaded

diff --git a/kernel/kexec_internal.h b/kernel/kexec_internal.h
index 48aaf2a..39d30cc 100644 (file)
--- a/kernel/kexec_internal.h
+++ b/kernel/kexec_internal.h
@@ -13,6 +13,8 @@ void kimage_terminate(struct kimage *image);
 int kimage_is_destination_range(struct kimage *image,
                                unsigned long start, unsigned long end);
 
+int machine_kexec_post_load(struct kimage *image);
+
 extern struct mutex kexec_mutex;
 
 #ifdef CONFIG_KEXEC_FILE