On Mon, Jun 29, 2026 at 2:50 PM Xiang Mei <[email protected]> wrote: > > An AI reviewer found an issue: > https://sashiko.dev/#/patchset/[email protected] > And that's correct; we added one more change in v2: > > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -3217,7 +3217,7 @@ struct vm_struct *__get_vm_area_node(unsigned long size, > return NULL; > if (!(flags & VM_NO_GUARD)) > - size += PAGE_SIZE; > + size += VMAP_GUARD_SIZE; > area->flags = flags; > area->caller = caller; > Sorry for my mistake; the change I made was wrong. What we added in v2 is:
``` @@ -5027,7 +5027,7 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, spin_lock(&vn->busy.lock); insert_vmap_area(vas[area], &vn->busy.root, &vn->busy.head); - setup_vmalloc_vm(vms[area], vas[area], VM_ALLOC, + setup_vmalloc_vm(vms[area], vas[area], VM_ALLOC | VM_NO_GUARD, pcpu_get_vm_areas); spin_unlock(&vn->busy.lock); } ``` Xiang > v2 was sent: > https://lore.kernel.org/linux-mm/[email protected]/T/#u > > Thanks, > Xiang > > On Mon, Jun 29, 2026 at 10:21 AM Xiang Mei <[email protected]> wrote: > > > > On Mon, Jun 29, 2026 at 5:50 AM H. Peter Anvin <[email protected]> wrote: > > > > > > On 2026-06-28 21:43, Matthew Wilcox wrote: > > > > On Sun, Jun 28, 2026 at 07:09:37PM -0700, H. Peter Anvin wrote: > > > >> > > > >>> 2) `enter` is not rare since we can take part in the instruction. > > > >> > > > >> This sentence doesn't parse. > > > > > > > > They mean that we can jump into the middle of an instruction, and it is > > > > not rare to see a 'c8' byte in the instruction stream. > > > > > > > > > > OK, I see the point now. The main difference is that ENTER doesn't > > > require a > > > REX prefix, whereas ADD/SUB/LEA do (otherwise it truncates RSP and > > > everything > > > immediately dies as a result of SMAP violations [you are welcome].) > > > > > > > Yes, Matthew's explanation is correct. (Btw, thanks Matthew!) > > > > Xiang > > > > > This means that an offending bit combination is far less common. > > > > > > -hpa > > >
