From mboxrd@z Thu Jan 1 00:00:00 1970 From: Catalin Marinas Subject: Re: [PATCH v2 06/29] ARM: add migrate_pages() system call Date: Fri, 25 Jan 2019 15:16:42 +0000 Message-ID: <20190125151641.GF25901@arrakis.emea.arm.com> References: <20190118161835.2259170-1-arnd@arndb.de> <20190118161835.2259170-7-arnd@arndb.de> Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: <20190118161835.2259170-7-arnd@arndb.de> Sender: netdev-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Arnd Bergmann Cc: y2038@lists.linaro.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, mattst88@gmail.com, linux@armlinux.org.uk, will.deacon@arm.com, tony.luck@intel.com, fenghua.yu@intel.com, geert@linux-m68k.org, monstr@monstr.eu, paul.burton@mips.com, deller@gmx.de, benh@kernel.crashing.org, mpe@ellerman.id.au, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, dalias@libc.org, davem@davemloft.net, luto@kernel.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, jcmvbkbc@gmail.com, akpm@linux-foundation.org, deepa.kernel@gmail.com, ebiederm@xmission.com, firoz.khan@linaro.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org On Fri, Jan 18, 2019 at 05:18:12PM +0100, Arnd Bergmann wrote: > The migrate_pages system call has an assigned number on all architectures > except ARM. When it got added initially in commit d80ade7b3231 ("ARM: > Fix warning: #warning syscall migrate_pages not implemented"), it was > intentionally left out based on the observation that there are no 32-bit > ARM NUMA systems. > > However, there are now arm64 NUMA machines that can in theory run 32-bit > kernels (actually enabling NUMA there would require additional work) > as well as 32-bit user space on 64-bit kernels, so that argument is no > longer very strong. > > Assigning the number lets us use the system call on 64-bit kernels as well > as providing a more consistent set of syscalls across architectures. > > Signed-off-by: Arnd Bergmann For the arm64 part: Acked-by: Catalin Marinas