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charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, Aug 28, 2025 at 7:11=E2=80=AFPM Lorenzo Stoakes wrote: > > On Thu, Aug 28, 2025 at 02:12:12PM +0800, Yafang Shao wrote: > > On Wed, Aug 27, 2025 at 11:46=E2=80=AFPM Lorenzo Stoakes > > wrote: > > > > > > On Tue, Aug 26, 2025 at 03:19:42PM +0800, Yafang Shao wrote: > > > > Every VMA must have an associated mm_struct, and it is safe to acce= ss > > > > > > Err this isn't true? Pretty sure special VMAs don't have that set. > > > > I=E2=80=99m not aware of any VMA that doesn=E2=80=99t belong to an mm_s= truct. If there > > is such a case, it would be helpful if you could point it out. In any > > case, I=E2=80=99ll remove the VMA-related code in the next version sinc= e it=E2=80=99s > > unnecessary. > > If you lok at get_vma_name() in fs/proc/task_mmu.c you'll see: > > if (!vma->vm_mm) { > *name =3D "[vdso]"; > return; > } > > So a VDSO will have this condition. > > I did a quick drgn()/printk() test and didn't see any, but maybe my syste= m - but > in any case this appears to be a valid situation that can arise, presumab= ly > because it's a VMA somehow shared with multiple mm's or something truly g= od > awful like that :) Thanks for clarifying that. --=20 Regards Yafang