Re: [PATCH] mm: pgtable: Ensure pml spinlock gets unlock

[Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>]

On 2025/2/10 16:31, Qi Zheng wrote:
>

[...]

> > > > diff --git a/mm/pt_reclaim.c b/mm/pt_reclaim.c
> > > > index 7e9455a18aae..163e38f1728d 100644
> > > > --- a/mm/pt_reclaim.c
> > > > +++ b/mm/pt_reclaim.c
> > > > @@ -43,7 +43,7 @@ void try_to_free_pte(struct mm_struct *mm, pmd_t 
> > > > *pmd, unsigned long addr,
> > > >        pml = pmd_lock(mm, pmd);
> > > >        start_pte = pte_offset_map_rw_nolock(mm, pmd, addr, &pmdval, 
> > > > &ptl);
> > > >        if (!start_pte)

Maybe we can return directly here:

            if (!start_pte) {
		spin_unlock(pml);
                return;
            }

> > > > -        goto out_ptl;
> > > > +        goto out_pte;
> > > >        if (ptl != pml)
> > > >            spin_lock_nested(ptl, SINGLE_DEPTH_NESTING);
> > > > @@ -68,4 +68,8 @@ void try_to_free_pte(struct mm_struct *mm, pmd_t 
> > > > *pmd, unsigned long addr,
> > > >            pte_unmap_unlock(start_pte, ptl);
> > > >        if (ptl != pml)
> > > >            spin_unlock(pml);
> > > > +    return;
> > > > +
> > > > +out_pte:
> > > > +    spin_unlock(pml);
> > > >    }