svn commit: r213359 - head/sys/kern

[Konstantin Belousov]

Author: kib
Date: Sat Oct  2 16:04:50 2010
New Revision: 213359
URL: http://svn.freebsd.org/changeset/base/213359

Log:
  Release the vnode lock and close the linker file vnode earlier in
  the linker_load_file methods. The change is that the consequent
  linker_file_unload() call is not under the vnode lock anymore.
  This prevents the LOR between kernel linker sx xlock and vnode lock,
  because linker_file_unload() relocks kernel linker lock.
  
  MFC after:	2 weeks

Modified:
  head/sys/kern/link_elf.c
  head/sys/kern/link_elf_obj.c

Modified: head/sys/kern/link_elf.c
==============================================================================
--- head/sys/kern/link_elf.c	Sat Oct  2 11:45:18 2010	(r213358)
+++ head/sys/kern/link_elf.c	Sat Oct  2 16:04:50 2010	(r213359)
@@ -967,15 +967,15 @@ nosyms:
     *result = lf;
 
 out:
+    VOP_UNLOCK(nd.ni_vp, 0);
+    vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
+    VFS_UNLOCK_GIANT(vfslocked);
     if (error && lf)
 	linker_file_unload(lf, LINKER_UNLOAD_FORCE);
     if (shdr)
 	free(shdr, M_LINKER);
     if (firstpage)
 	free(firstpage, M_LINKER);
-    VOP_UNLOCK(nd.ni_vp, 0);
-    vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
-    VFS_UNLOCK_GIANT(vfslocked);
 
     return error;
 }

Modified: head/sys/kern/link_elf_obj.c
==============================================================================
--- head/sys/kern/link_elf_obj.c	Sat Oct  2 11:45:18 2010	(r213358)
+++ head/sys/kern/link_elf_obj.c	Sat Oct  2 16:04:50 2010	(r213359)
@@ -885,13 +885,13 @@ link_elf_load_file(linker_class_t cls, c
 	*result = lf;
 
 out:
+	VOP_UNLOCK(nd.ni_vp, 0);
+	vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
+	VFS_UNLOCK_GIANT(vfslocked);
 	if (error && lf)
 		linker_file_unload(lf, LINKER_UNLOAD_FORCE);
 	if (hdr)
 		free(hdr, M_LINKER);
-	VOP_UNLOCK(nd.ni_vp, 0);
-	vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
-	VFS_UNLOCK_GIANT(vfslocked);
 
 	return error;
 }