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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: C46792001B X-Stat-Signature: 63t33zwuw53p34k84mukg9k68eh9dejg X-Rspam-User: X-HE-Tag: 1720164038-681228 X-HE-Meta: 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 FzKmjQwe 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 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 Thu, Jul 04, 2024 at 02:43:04PM -0600, Martin Oliveira wrote: > On 2024-07-04 11:02, Matthew Wilcox wrote:> Seems to me we should actually _handle_ that, not do something wrong. > > eg: > > > > if (vma->vm_ops) { > > if (vma->vm_ops->close) > > goto out_put; > > if (WARN_ON(vma->vm_ops->page_mkwrite)) > > goto out_put; > > } > > Good point. Btw, sorry if I mislead you with my WARN_ON_ONCE suggestion. That was always intended in addition to the error handling, not instead. (In fact there are very few reasons to use WARN_ON* without actually handling the error as well). > > > or maybe this doesn't need to be a WARN at all? After all, there > > isn't one for having a ->close method, so why is page_mkwrite special? > > Hmm yeah, they should probably be treated the same. > > Maybe ->close should be converted to WARN as well? It would be easier to > catch an error this way than chasing the EINVAL, but I'm OK either way. Yes, doing the same for ->close or anything unimplemented would be nice. But it's not really in scope for this series. kernfs really should be using it's own ops instead of abusing file_operations, but that's even more out of scope..