• Vincenzo Frascino's avatar
    arm64: compat: Add vDSO · a7f71a2c
    Vincenzo Frascino authored
    Provide the arm64 compat (AArch32) vDSO in kernel/vdso32 in a similar
    way to what happens in kernel/vdso.
    
    The compat vDSO leverages on an adaptation of the arm architecture code
    with few changes:
    
     - Use of lib/vdso for gettimeofday
     - Implement a syscall based fallback
     - Introduce clock_getres() for the compat library
     - Implement trampolines
     - Implement elf note
    
    To build the compat vDSO a 32 bit compiler is required and needs to be
    specified via CONFIG_CROSS_COMPILE_COMPAT_VDSO.
    
    The code is not yet enabled as other prerequisites are missing.
    Signed-off-by: default avatarVincenzo Frascino <vincenzo.frascino@arm.com>
    Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
    Tested-by: default avatarShijith Thotton <sthotton@marvell.com>
    Tested-by: default avatarAndre Przywara <andre.przywara@arm.com>
    Cc: linux-arch@vger.kernel.org
    Cc: linux-arm-kernel@lists.infradead.org
    Cc: linux-mips@vger.kernel.org
    Cc: linux-kselftest@vger.kernel.org
    Cc: Catalin Marinas <catalin.marinas@arm.com>
    Cc: Will Deacon <will.deacon@arm.com>
    Cc: Arnd Bergmann <arnd@arndb.de>
    Cc: Russell King <linux@armlinux.org.uk>
    Cc: Ralf Baechle <ralf@linux-mips.org>
    Cc: Paul Burton <paul.burton@mips.com>
    Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
    Cc: Mark Salyzyn <salyzyn@android.com>
    Cc: Peter Collingbourne <pcc@google.com>
    Cc: Shuah Khan <shuah@kernel.org>
    Cc: Dmitry Safonov <0x7f454c46@gmail.com>
    Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
    Cc: Huw Davies <huw@codeweavers.com>
    Link: https://lkml.kernel.org/r/20190621095252.32307-11-vincenzo.frascino@arm.com
    a7f71a2c
vgettimeofday.c 1.19 KB