On 02/26, Oleg Nesterov wrote:
>
> On 02/24, jef...@chromium.org wrote:
> >
> > Unlike other system mappings, the uprobe mapping is not
> > established during program startup. However, its lifetime is the same
> > as the process's lifetime. It could be sealed from creation.
>
> Agreed, VM_SEALED should be always for the "[uprobes]" vma, regardless
> of config options.
>
> ACK,
>
> but can't we do
>
> #ifdef CONFIG_64BIT
> /* VM is sealed, in vm_flags */
> #define VM_SEALED _BITUL(63)
> + #else
> + #define VM_SEALED 0
> #endif
>
> and then simply
>
> vma = _install_special_mapping(mm, area->vaddr, PAGE_SIZE,
> - VM_EXEC|VM_MAYEXEC|VM_DONTCOPY|VM_IO,
> + VM_EXEC|VM_MAYEXEC|VM_DONTCOPY|VM_IO|VM_SEALED,
>
> ?
>
> But I am fine either way, feel free to ignore.
Yes, but either way, why your patch adds "unsigned long vm_flags" ?
OK, perhaps it makes sense for readability, but
vm_flags = VM_EXEC|VM_MAYEXEC|VM_DONTCOPY|VM_IO;
vm_flags |= VM_SEALED_SYSMAP;
looks a bit strange, why not
vm_flags = VM_EXEC|VM_MAYEXEC|VM_DONTCOPY|VM_IO|VM_SEALED_SYSMAP;
?
Oleg.
