[mini-os master] mini-os: kexec: do the final kexec step

[patchbot@xxxxxxx]

commit 560c2a5584c4ae031277e06c745ad07a444e9f54
Author:     Juergen Gross <jgross@xxxxxxxx>
AuthorDate: Mon Jun 23 10:42:53 2025 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon Jun 23 10:42:53 2025 +0200

    mini-os: kexec: do the final kexec step
    
    With all kexec preparations done, activate the new kernel.
    
    Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
    Reviewed-by: Jason Andryuk <jason.andryuk@xxxxxxx>
---
 kexec.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/kexec.c b/kexec.c
index f42aa8a..2607c81 100644
--- a/kexec.c
+++ b/kexec.c
@@ -168,6 +168,7 @@ int kexec(void *kernel, unsigned long kernel_size, const 
char *cmdline)
 {
     int ret;
     unsigned long *func;
+    void *kexec_page;
 
     ret = analyze_kernel(kernel, kernel_size);
     if ( ret )
@@ -191,6 +192,13 @@ int kexec(void *kernel, unsigned long kernel_size, const 
char *cmdline)
     if ( ret )
         goto err;
 
+    kexec_page = (void *)alloc_page();
+    if ( !kexec_page )
+    {
+        ret = ENOMEM;
+        goto err;
+    }
+
     for ( func = __kexec_array_start; func < __kexec_array_end; func++ )
     {
         ret = ((kexeccall_t)(*func))(false);
@@ -203,10 +211,15 @@ int kexec(void *kernel, unsigned long kernel_size, const 
char *cmdline)
         }
     }
 
-    /* Error exit. */
-    ret = ENOSYS;
+    /* Activate the new kernel. */
+    do_kexec(kexec_page);
+
+    /* do_kexec() shouldn't return, crash. */
+    BUG();
 
  err:
+    if ( kexec_page )
+        free_page(kexec_page);
     change_readonly(true);
     unreserve_memory_below();
     kexec_move_used_pages_undo();
--
generated by git-patchbot for /home/xen/git/mini-os.git#master