Re: [PATCH mm-unstable 1/2] mseal sysmap: generic vdso vvar mapping

From: Jeff Xu
Date: Tue Mar 11 2025 - 17:55:00 EST


On Tue, Mar 11, 2025 at 5:33 AM Heiko Carstens <hca@xxxxxxxxxxxxx> wrote:
>
> 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.
>
Thanks for fixing this merging problem.
The new selftest in mseal_system_mappings should catch this :-)

Hi Andrew,
when you apply this to mm-unstable, could you please insert this between:

commit 5bda54a4f304a7c3d65a40c9c3f015901caa2ce6
selftests: x86: test_mremap_vdso: skip if vdso is msealed
and
commit 884323e928c6938923e5dfcb8a601b3363e1130b
mseal sysmap: enable x86-64

That will make the series complete.


> [1] https://lkml.kernel.org/r/20250305021711.3867874-4-jeffxu@xxxxxxxxxx
> [2] https://lkml.kernel.org/r/20250305021711.3867874-5-jeffxu@xxxxxxxxxx
>
> Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
> ---
> lib/vdso/datastore.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/lib/vdso/datastore.c b/lib/vdso/datastore.c
> index e227fbbcb796..b7c7386c98a9 100644
> --- a/lib/vdso/datastore.c
> +++ b/lib/vdso/datastore.c
> @@ -99,7 +99,8 @@ const struct vm_special_mapping vdso_vvar_mapping = {
> 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);
> }
>
> --
> 2.45.2
>
Reviewed-by: Jeff Xu <jeffxu@xxxxxxxxxxxx>