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charset=us-ascii Content-Disposition: inline In-Reply-To: <87v8e0m26q.ffs@tglx> X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 4A5904000A X-Stat-Signature: kurrrtwr1fjat58x4cqhd7d547gmkang X-HE-Tag: 1690824926-674982 X-HE-Meta: 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 in6lkCGn yZaRkXl+c4NIJF7afD3oWSA+o91zAZWA3flVf1kJCIifXW4HEozSMOi4/AkxaygmNnKQOm1/vAbCxi90uCLWJuSV1k6FGB4EE0PPi5sYFBIV0r1ggmOe1/WvRST6TuFgCodL0PfoICnH61T8= 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, Jul 31, 2023 at 07:16:29PM +0200, Thomas Gleixner wrote: > On Mon, Jul 31 2023 at 18:11, Thomas Gleixner wrote: > > On Fri, Jul 21 2023 at 12:22, Peter Zijlstra wrote: > >> -#define FUTEX2_MASK (FUTEX2_32 | FUTEX2_PRIVATE) > >> +#define FUTEX2_MASK (FUTEX2_64 | FUTEX2_PRIVATE) > >> > >> /** > >> * futex_parse_waitv - Parse a waitv array from userspace > >> @@ -207,7 +207,12 @@ static int futex_parse_waitv(struct fute > >> if ((aux.flags & ~FUTEX2_MASK) || aux.__reserved) > >> return -EINVAL; > > > > With the above aux.flags with FUTEX2_32 set will result in -EINVAL. I > > don't think that's intentional. > > Also if you allow 64bit wide futexes, how is that supposed to work with > the existing code, which clearly expects a 32bit uval throughout the > place? Not allowed yet, these patches only allow 8,16,32. I still need to audit the whole futex core and do 'u32 -> unsigned long' (and everything else that follows from that), and only when that's done can the futex2 syscalls allow FUTEX2_64 on 64bit archs. So for now, these patches: - add the FUTEX2_64 flag, - add 'unsigned long' interface such that 64bit can potentiall use it, - explicitly disallow having it set.