Re: [PATCH v2 12/26] iommu/amd: Add per-VM private IPA alloc/map helpers

[Suthikulpanit, Suravee]

On 5/31/2026 3:44 AM, Weinan Liu wrote:
> On Wed, May 27, 2026 at 10:19 PM Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx> wrote:
> > +static void __maybe_unused free_private_vm_region(struct amd_iommu *iommu, u64 **entry,
> > +                                                 u64 base, size_t size, u16 gid)
> > +{
> > +       size_t unmapped;
> > +       u64 addr = base + (gid * size);
> > +
> > +       pr_debug("%s: entry=%#llx(%#llx), base=%#llx, addr=%#llx, size=%#lx\n",
> > +                __func__, (unsigned long  long)*entry,
> > +                iommu_virt_to_phys(*entry), base, addr, size);
> > +
> > +       if (!iommu || !iommu->viommu_pdom)
> > +               return;
>
> Should check if the page pointer *entry is non-NULL before operating on it.
> *entry  will be  NULL if the caller encounters an error during alloc_private_vm_region(),
> it may attempt to unmap and free a NULL pointer below:

Thanks. I'll take care of this in V3.
Suravee