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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.46.4 (3.46.4-1.fc37) MIME-Version: 1.0 X-Rspamd-Queue-Id: 449A3A0010 X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: mfnykorixjeqeq77r7x4kcrae9i81hzt X-HE-Tag: 1695689258-500024 X-HE-Meta: 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 Fi6Br73u PRK/ukf41MknWJ7o1juQX+inUeKDR3ilzp+0Mh8BteqnjKQfOn3/7lQB8gRfXohkdnOEOjsk4FvJ6hVRe9QaWYirKCWW/NwgJ9ZUEgaH8VW/vOQykWVYiJJyIt1fiJqNo3xlbdRX0LNkQ+dRBwYb65m90IzDfrxR02NrfnJ/FruVqbBpzoWTmBqWJw6DXILW3dUFauzFERQ+Mx4Yj5gTcrUbhfMrLk862+H7li1qhFjUOKU0azJHskKZ1+B2bmwyo2iM1/fFKBHTY+w+KgQQxB+1thY9oUoJPN/xPN/mC9mtOZhrgXeQIgtvrA4+CzIVsP9suO8g3wiIxE99A6Lx6r8Cnmw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, 2023-09-25 at 15:25 -0700, Mike Kravetz wrote: > On 09/25/23 16:28, riel@surriel.com=C2=A0wrote: > >=20 > > -void __unmap_hugepage_range_final(struct mmu_gather *tlb, > > -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= struct vm_area_struct *vma, unsigned long > > start, > > -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= unsigned long end, struct page *ref_page, > > -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= zap_flags_t zap_flags) > > +void __hugetlb_zap_begin(struct vm_area_struct *vma, > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 unsig= ned long *start, unsigned long *end) > > =C2=A0{ > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0adjust_range_if_pmd_sharing_= possible(vma, start, end); > > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0hugetlb_vma_lock_write(= vma); > > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0i_mmap_lock_write(vma->= vm_file->f_mapping); > > +} >=20 > __unmap_hugepage_range_final() was called from unmap_single_vma. > unmap_single_vma has two callers, zap_page_range_single and > unmap_vmas. >=20 > When the locking was moved into hugetlb_zap_begin, it was only added > to the > zap_page_range_single call path.=C2=A0 Calls from unmap_vmas are missing > the > locking. Oh, that's a fun one. I suppose the locking of the f_mapping lock, and calling adjust_range_if_pmd_sharing_possible matters for the call from unmap_vmas, while the call tho hugetlb_vma_lock_write really doesn't matter, since unmap_vmas is called with the mmap_sem held for write, which already excludes page faults. I'll add the call there for v4. Good catch. --=20 All Rights Reversed.