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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 9E54820037 X-Rspam-User: X-Stat-Signature: wap8k77ddr4wxaosqeknfmzgaz18abz3 X-Rspamd-Server: rspam03 X-HE-Tag: 1695380638-444360 X-HE-Meta: U2FsdGVkX1+NE/HB1qsWZs5aqAWG8mroPs7dMSTX+Ecg4FlVCGcvZ33IqMh3eOoqdE2eLhtHTnJVHEFja2gza7ihE31Dti/hvzi+kd6hh4+jtO1A0QqkpmnhYc6Z2Tq0/wiYy30hh+uA8JNl89tly9cjAECoemUZrYDNKQ9aEilwsTI4m5PA1F6XhdpF48r2K9ajXk76SGKXyAWuWISsFjdmV8RKpdYyjMMfb8hfONp26942ZPdifNOx+1EtLEBK1laF//q6IKVmEJ5OP1H8zRhv/s2ARblfe5JMfvLAlaULW30dhQAw4REKEPKLZ9m7FIQ+7KBL0B+wXDitb1h11XZeEqVr2JA9Qko+6RKbYSpz7PxlH3wd0nLDG5qO14SmCIl+9LzZunkJGCQBh7aIt++jMRXjOZ/bBEQIYg9l6yfjWclkivtSmQiDEjelPNHJF7Rpq9Zpkg+XC/dXvtPgXUujioLxJOcBsHx5/PFaXpcZX2IuVUmxF4V2uKZLb6Kj4+ZFgUS6E/pl0WimExJtnsZo646FSOdwwiVslB6rYrzugiHIEQmq1SieUCUodSqcUhnQCRLftNkEn8ZcdMjlogI9zbCR5w7Y+UTNECoBarUWtONXQflMQV1SrNn/sdSzhURdhVdGaOMH6ODNVUWCDXE+h1jnp1FlugZRZArKkTO/OSsTjIwqSAUGm/UQvX6sfmX82pavvhSx3zYxiDIHNFKUsXw8rZ0gevx4vq+i5k8zbl874OvDG30Eh5nRUyfkBULngc/9IrHmNAvSpo1Ly6gmBw9czJnTOCa6gPk+XhknqFbqtA0LyZoeksFZBq69mBx7UzXzeHw5aognydGjxACaeMe9VGu92J5VyW6z8gHDd9O7ac1BuOigbA4sTyymUXm3tP29Lrj6NRUw4SL0fZhuUIlfR8Si8rxvEgc5JxRfLVoJKovZtKEoDpakiPUh9IXBZp+1C45uumfxZk0 0LWANToo 1UPgcVIrx8x/2o5d2eL2d0pPEvwUfQUkLtlsioGNRjbPjP2yu75FjtGTmyXj0HN0VufjmgezC53frPgjwq9TElfxIQfIFn5Fy/SyWJs+3F1lfxIHAM/hs3k+HW34FYfFlA7xCMvdjdlewL44wZTGUDv/G167/kS+vNPx1InpKCblwWbiKVHdnMaZ1VSprm95a0AQsZLztmcm76L9uhZdFFbGLkCk6h0aL+rqZMfVd3DPtSkpvo3pzJJdmPg== 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 Fri, Sep 22, 2023 at 11:35:03AM +0200, Ingo Molnar wrote: > > * peterz@infradead.org wrote: > > > --- linux-2.6.orig/kernel/futex/syscalls.c > > +++ linux-2.6/kernel/futex/syscalls.c > > @@ -396,6 +396,44 @@ SYSCALL_DEFINE6(futex_wait, > > return ret; > > } > > > > +/* > > + * sys_futex_requeue - Requeue a waiter from one futex to another > > + * @waiters: array describing the source and destination futex > > + * @flags: unused > > + * @nr_wake: number of futexes to wake > > + * @nr_requeue: number of futexes to requeue > > + * > > + * Identical to the traditional FUTEX_CMP_REQUEUE op, except it is part of the > > + * futex2 family of calls. > > + */ > > + > > +SYSCALL_DEFINE4(futex_requeue, > > + struct futex_waitv __user *, waiters, > > + unsigned int, flags, > > + int, nr_wake, > > + int, nr_requeue) > > +{ > > + struct futex_vector futexes[2]; > > + u32 cmpval; > > + int ret; > > + > > + if (flags) > > + return -EINVAL; > > Small detail, but isn't -ENOSYS the canonical error code for functionality > not yet implemented - which the unused 'flags' ABI is arguably? > > -EINVAL is for recognized but incorrect parameters, such as: IIUC 'unknown flag' falls into the -EINVAL return category. Here we happen to have no known flags, but that should not matter.