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authorLinus Torvalds <torvalds@linux-foundation.org>2016-05-23 19:42:28 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-05-23 19:42:28 -0700
commit84787c572d402644dca4874aba73324d9f8e3948 (patch)
tree31783e50b09fee00ee7ff87c0c9708a3c7106482 /kernel/kexec.c
parentd62a0234c87f1457a3d2ba519ef90cf164a5eb23 (diff)
parentc5d2cac0f1caaf7dd21350146fb29c55b3e74249 (diff)
Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton: - Oleg's "wait/ptrace: assume __WALL if the child is traced". It's a kernel-based workaround for existing userspace issues. - A few hotfixes - befs cleanups - nilfs2 updates - sys_wait() changes - kexec updates - kdump - scripts/gdb updates - the last of the MM queue - a few other misc things * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (84 commits) kgdb: depends on VT drm/amdgpu: make amdgpu_mn_get wait for mmap_sem killable drm/radeon: make radeon_mn_get wait for mmap_sem killable drm/i915: make i915_gem_mmap_ioctl wait for mmap_sem killable uprobes: wait for mmap_sem for write killable prctl: make PR_SET_THP_DISABLE wait for mmap_sem killable exec: make exec path waiting for mmap_sem killable aio: make aio_setup_ring killable coredump: make coredump_wait wait for mmap_sem for write killable vdso: make arch_setup_additional_pages wait for mmap_sem for write killable ipc, shm: make shmem attach/detach wait for mmap_sem killable mm, fork: make dup_mmap wait for mmap_sem for write killable mm, proc: make clear_refs killable mm: make vm_brk killable mm, elf: handle vm_brk error mm, aout: handle vm_brk failures mm: make vm_munmap killable mm: make vm_mmap killable mm: make mmap_sem for write waits killable for mm syscalls MAINTAINERS: add co-maintainer for scripts/gdb ...
Diffstat (limited to 'kernel/kexec.c')
-rw-r--r--kernel/kexec.c109
1 files changed, 60 insertions, 49 deletions
diff --git a/kernel/kexec.c b/kernel/kexec.c
index ee70aef5cd81..4384672d3245 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -103,6 +103,65 @@ out_free_image:
return ret;
}
+static int do_kexec_load(unsigned long entry, unsigned long nr_segments,
+ struct kexec_segment __user *segments, unsigned long flags)
+{
+ struct kimage **dest_image, *image;
+ unsigned long i;
+ int ret;
+
+ if (flags & KEXEC_ON_CRASH) {
+ dest_image = &kexec_crash_image;
+ if (kexec_crash_image)
+ arch_kexec_unprotect_crashkres();
+ } else {
+ dest_image = &kexec_image;
+ }
+
+ if (nr_segments == 0) {
+ /* Uninstall image */
+ kimage_free(xchg(dest_image, NULL));
+ return 0;
+ }
+ if (flags & KEXEC_ON_CRASH) {
+ /*
+ * Loading another kernel to switch to if this one
+ * crashes. Free any current crash dump kernel before
+ * we corrupt it.
+ */
+ kimage_free(xchg(&kexec_crash_image, NULL));
+ }
+
+ ret = kimage_alloc_init(&image, entry, nr_segments, segments, flags);
+ if (ret)
+ return ret;
+
+ if (flags & KEXEC_PRESERVE_CONTEXT)
+ image->preserve_context = 1;
+
+ ret = machine_kexec_prepare(image);
+ if (ret)
+ goto out;
+
+ for (i = 0; i < nr_segments; i++) {
+ ret = kimage_load_segment(image, &image->segment[i]);
+ if (ret)
+ goto out;
+ }
+
+ kimage_terminate(image);
+
+ /* Install the new kernel and uninstall the old */
+ image = xchg(dest_image, image);
+
+out:
+ if ((flags & KEXEC_ON_CRASH) && kexec_crash_image)
+ arch_kexec_protect_crashkres();
+
+ kimage_free(image);
+ return ret;
+}
+
/*
* Exec Kernel system call: for obvious reasons only root may call it.
*
@@ -127,7 +186,6 @@ out_free_image:
SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
struct kexec_segment __user *, segments, unsigned long, flags)
{
- struct kimage **dest_image, *image;
int result;
/* We only trust the superuser with rebooting the system. */
@@ -152,9 +210,6 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
if (nr_segments > KEXEC_SEGMENT_MAX)
return -EINVAL;
- image = NULL;
- result = 0;
-
/* Because we write directly to the reserved memory
* region when loading crash kernels we need a mutex here to
* prevent multiple crash kernels from attempting to load
@@ -166,53 +221,9 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
if (!mutex_trylock(&kexec_mutex))
return -EBUSY;
- dest_image = &kexec_image;
- if (flags & KEXEC_ON_CRASH)
- dest_image = &kexec_crash_image;
- if (nr_segments > 0) {
- unsigned long i;
-
- if (flags & KEXEC_ON_CRASH) {
- /*
- * Loading another kernel to switch to if this one
- * crashes. Free any current crash dump kernel before
- * we corrupt it.
- */
-
- kimage_free(xchg(&kexec_crash_image, NULL));
- result = kimage_alloc_init(&image, entry, nr_segments,
- segments, flags);
- crash_map_reserved_pages();
- } else {
- /* Loading another kernel to reboot into. */
-
- result = kimage_alloc_init(&image, entry, nr_segments,
- segments, flags);
- }
- if (result)
- goto out;
-
- if (flags & KEXEC_PRESERVE_CONTEXT)
- image->preserve_context = 1;
- result = machine_kexec_prepare(image);
- if (result)
- goto out;
-
- for (i = 0; i < nr_segments; i++) {
- result = kimage_load_segment(image, &image->segment[i]);
- if (result)
- goto out;
- }
- kimage_terminate(image);
- if (flags & KEXEC_ON_CRASH)
- crash_unmap_reserved_pages();
- }
- /* Install the new kernel, and Uninstall the old */
- image = xchg(dest_image, image);
+ result = do_kexec_load(entry, nr_segments, segments, flags);
-out:
mutex_unlock(&kexec_mutex);
- kimage_free(image);
return result;
}