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charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 X-Stat-Signature: qgq8i5exxan98cippm7cjuia7cux7xj6 X-Rspamd-Queue-Id: 84D59160005 X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1748623731-528720 X-HE-Meta: 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 I71/O60u AE2spFh9Pw+9yf6gttrbzJU/BuilOBMzPrtx8r7P230rnY4iqzRhxZO5eJwsGbI98YgVlCggdREHJ2C7Fu7XrEAw3qw8RdRVzn2Lhh3DA+qu8VVBg2y/hYLhAt47w916RzO17WV3X6lXBwR40TnAgceYk5kmDGpQpnOLYd7A7sU++YLd2ORsuplMC8QdIGeaAKGlyZSe3B7+oEnAu7NMkmE9eRytZdZOrSycWIpdRIscm5W5GWV9u8Ek8pkqQr6mxlaRUZcNg0E06IoP2sAf4mUkytU8qPBSyBJnguTHen0Ln2tvGAVfbyLt2c+R9CNSw8fCJwPU5KsAok8cCDtFIczCa4N2NFBTFihi4L2UIYRohgts= 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: List-Subscribe: List-Unsubscribe: On 05/30, Lorenzo Stoakes wrote: > > > --- a/mm/mremap.c > > +++ b/mm/mremap.c > > @@ -237,6 +237,8 @@ static int move_ptes(struct pagetable_move_control *pmc, > > > > for (; old_addr < old_end; old_pte++, old_addr += PAGE_SIZE, > > new_pte++, new_addr += PAGE_SIZE) { > > + WARN_ON_ONCE(!pte_none(*new_pte)); > > + > > I mean, we really really should not ever be seeing a mapped PTE here, so I think > a WARN_ON_ONCE() is fine. > > We unmap anything ahead of time, and only I think this uprobe breakpoint > installation would ever cause this to be the case. > > We can make this a VM_WARN_ON_ONCE() too I suppose, just in case there's > something we're not thinking of, but I'd say at some point we'd want to change > it to a WARN_ON_ONCE(). Note also that move_normal_pmd/move_normal_pud use WARN_ON_ONCE(!xxx_none(...)), not VM_WARN_ON_ONCE(). Oleg.