linux-kernel - Re: [PATCH 06/15] ARM: add migrate

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20190110163220.GB31683@fuggles.cambridge.arm.com>
Date:   Thu, 10 Jan 2019 16:32:20 +0000
From:   Will Deacon <will.deacon@....com>
To:     Arnd Bergmann <arnd@...db.de>
Cc:     y2038@...ts.linaro.org, linux-api@...r.kernel.org,
        linux-kernel@...r.kernel.org, ink@...assic.park.msu.ru,
        mattst88@...il.com, linux@...linux.org.uk, catalin.marinas@....com,
        tony.luck@...el.com, fenghua.yu@...el.com, geert@...ux-m68k.org,
        monstr@...str.eu, paul.burton@...s.com, deller@....de,
        mpe@...erman.id.au, schwidefsky@...ibm.com,
        heiko.carstens@...ibm.com, dalias@...c.org, davem@...emloft.net,
        luto@...nel.org, tglx@...utronix.de, mingo@...hat.com,
        hpa@...or.com, x86@...nel.org, jcmvbkbc@...il.com,
        firoz.khan@...aro.org, ebiederm@...ssion.com,
        deepa.kernel@...il.com, linux@...inikbrodowski.net,
        akpm@...ux-foundation.org, dave@...olabs.net,
        linux-alpha@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-ia64@...r.kernel.org, linux-m68k@...ts.linux-m68k.org,
        linux-mips@...r.kernel.org, linux-parisc@...r.kernel.org,
        linuxppc-dev@...ts.ozlabs.org, linux-s390@...r.kernel.org,
        linux-sh@...r.kernel.org, sparclinux@...r.kernel.org
Subject: Re: [PATCH 06/15] ARM: add migrate_pages() system call

On Thu, Jan 10, 2019 at 05:24:26PM +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 <arnd@...db.de>
> ---
>  arch/arm/include/asm/unistd.h     | 1 -
>  arch/arm/tools/syscall.tbl        | 1 +
>  arch/arm64/include/asm/unistd.h   | 2 +-
>  arch/arm64/include/asm/unistd32.h | 2 ++
>  4 files changed, 4 insertions(+), 2 deletions(-)

[...]

> diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h
> index 04ee190b90fe..355fe2bc035b 100644
> --- a/arch/arm64/include/asm/unistd32.h
> +++ b/arch/arm64/include/asm/unistd32.h
> @@ -821,6 +821,8 @@ __SYSCALL(__NR_statx, sys_statx)
>  __SYSCALL(__NR_rseq, sys_rseq)
>  #define __NR_io_pgetevents 399
>  __SYSCALL(__NR_io_pgetevents, compat_sys_io_pgetevents)
> +#define __NR_migrate_pages 400
> +__SYSCALL(__NR_migrate_pages, sys_migrate_pages)

Should be compat_sys_migrate_pages instead?

Will