mseal sysmap: generic vdso vvar mapping

With the introduction of the generic vdso data storage the VM_SEALED_SYSMAP
vm flag must be moved from the architecture specific
_install_special_mapping() call [1] [2] which maps the vvar mapping to
generic code.

[1] https://lkml.kernel.org/r/[e-mail]
[2] https://lkml.kernel.org/r/[e-mail]

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Heiko Carstens <[e-mail]>
Reviewed-by: Lorenzo Stoakes <[e-mail]>
Cc: Alexander Gordeev <[e-mail]>
Cc: Christian Borntraeger <[e-mail]>
Cc: Jeff Xu <[e-mail]>
Cc: Liam Howlett <[e-mail]>
Cc: Sven Schnelle <[e-mail]>
Cc: Thomas Weißschuh <[e-mail]>
Cc: Vasily Gorbik <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

lib/vdso/datastore.c

···
 struct vm_area_struct *vdso_install_vvar_mapping(struct mm_struct *mm, unsigned long addr)
 {
 	return _install_special_mapping(mm, addr, VDSO_NR_PAGES * PAGE_SIZE,
-					VM_READ | VM_MAYREAD | VM_IO | VM_DONTDUMP | VM_PFNMAP,
+					VM_READ | VM_MAYREAD | VM_IO | VM_DONTDUMP |
+					VM_PFNMAP | VM_SEALED_SYSMAP,
 					&vdso_vvar_mapping);
 }