Re: [RFC2 PATCH v6 00/19] ILP32 for ARM64

["Zhangjian (Bamvor)" <bamvor.zhangjian@huawei.com>]

Hi, Yury

Glad to see the new version of ilp32. Here is some general questions:

On 2015/11/18 5:16, Yury Norov wrote:
> ------8<-----
> Colleagues, I'm gonna to send it to list.
> Please, take a look.
> ------8<-----
> 
> This is still RFC because ~20 tests still fail,
> and because it's based on 4.3 kernel version, and
> some work is needed to rebase on 4.4. I'd preffer
> to do it later. 
> 
> v3: https://lkml.org/lkml/2014/9/3/704
> v4: https://lkml.org/lkml/2015/4/13/691
> v5: https://lkml.org/lkml/2015/9/29/911
> 
> v6:
>  - time_t, __kenel_off_t and other types turned to be 32-bit
>    for compatibility reasons (after v5 discussion);
Is there any performance comparison between v6 and v5, especially for
these changes? Compatibility is important for us, meanwhile we need to
take performance into account.
>  - related changes applied to ILP32 syscall table and handlers;
>  - ILP32 VDSO code excluded. It's not mandatory, and caused questions
>    during review process. We definitely make sure we will follow up
>    with a VDSO later on because it is needed for performance reasons;
>  - fixed build issues with different combinations of AARCH32 / ILP32
>    enabling in config;
>  - ILP32 TLS bug fixed;
>  - entry32-common.S introduced to hold wrappers needed for both ILP32
>    and AARCH32_EL0;
>  - documentation updated according to latest changes;
>  - rebased to the current head;
>  - coding style re-checked;
>  - ILP32 syscall table turned around.
> 
> Testing is performed using LTP with scenario 'ltplite'.
> Tested on QEMU + vanilla defconfig kernel.
Do you tested on both big endian and little endian?

Regards

Bamvor
> Regressions are mostly related to core dump genereation,
> readdir(), and futex(). Some tests fail both in ILP32, and LP64.
> 
> The full regression table is:
> 		ILP32		LP64
> 
> float_bessel    FAIL	 134    PASSED	0
> float_exp_log   FAIL	 134    PASSED	0
> float_iperb     FAIL	 134    PASSED	0
> float_power     FAIL	 134    PASSED	0
> float_trigo     FAIL	 134    PASSED	0
> abort01         FAIL       2    FAIL 	2
> fcntl14         FAIL       2    FAIL 	2
> kill11          FAIL       2    FAIL 	2
> mmap16          FAIL       6    PASSED	0
> open12          FAIL       2    PASSED	0
> pause01         PASSED     0    FAIL 	9
> pipe07          FAIL       2    PASSED	0
> readdir01       FAIL       1    PASSED	0
> rename11        FAIL       2    PASSED	0
> rmdir02         FAIL       2    PASSED	0
> setregid02      FAIL       1    FAIL 	1
> settimeofday01  FAIL       1    FAIL 	1
> umount2_01      FAIL       2    PASSED	0
> umount2_02      FAIL       2    PASSED	0
> umount2_03      FAIL       2    PASSED	0
> utime06         FAIL       2    PASSED	0
> 
> Kernel with this patchset, and corresponding
> version of glibc is here:
> https://github.com/norov/
> 
> Andrew Pinski (14):
>   arm64: ensure the kernel is compiled for LP64
>   arm64: rename COMPAT to AARCH32_EL0 in Kconfig
>   arm64: change some CONFIG_COMPAT over to use CONFIG_AARCH32_EL0
>     instead
>   arm64:uapi: set __BITS_PER_LONG correctly for ILP32 and LP64
>   arm64:ilp32: share signal structures between ILP32 and LP64 ABIs
>   arm64: introduce is_a32_task and is_a32_thread (for AArch32 compat)
>   arm64:ilp32: add is_ilp32_compat_{task,thread} and TIF_32BIT_AARCH64
>   arm64:ilp32: share HWCAP between LP64 and ILP32
>   arm64:ilp32 use the native LP64 'start_thread' for ILP32 threads
>   arm64:ilp32: support core dump generation for ILP32
>   ptrace: Allow compat to use the native siginfo
>   arm64:ilp32: add sys_ilp32.c and a separate table (in entry.S) to use
>     it
>   arm64:ilp32: use the native siginfo instead of the compat siginfo
>   arm64:ilp32: add ARM64_ILP32 to Kconfig
> 
> Jan Dakinevich (2):
>   ilp32: common 32-bit wrappers
>   arm64: ilp32: force IPC_64 in msgctl, shmctl, semctl
> 
> Philipp Tomsich (2):
>   arm64:ilp32: add documentation on the ILP32 ABI for ARM64
>   arm64:ilp32: change COMPAT_ELF_PLATFORM to report a a subplatform for
>     ILP32
> 
> Yury Norov (1):
>   aarch64: ilp32: use generic stat64 structure
> 
>  Documentation/arm64/ilp32.txt             |  47 +++++++
>  arch/arm64/Kconfig                        |  12 ++
>  arch/arm64/Makefile                       |   5 +
>  arch/arm64/include/asm/compat.h           |  70 +++++++++-
>  arch/arm64/include/asm/elf.h              | 105 ++++++++++++--
>  arch/arm64/include/asm/fpsimd.h           |   2 +-
>  arch/arm64/include/asm/hwcap.h            |  12 +-
>  arch/arm64/include/asm/memory.h           |   2 +-
>  arch/arm64/include/asm/processor.h        |  18 ++-
>  arch/arm64/include/asm/ptrace.h           |   2 +-
>  arch/arm64/include/asm/signal32.h         |  19 +++
>  arch/arm64/include/asm/stat.h             |   2 +
>  arch/arm64/include/asm/thread_info.h      |   3 +-
>  arch/arm64/include/asm/unistd.h           |  11 +-
>  arch/arm64/include/uapi/asm/bitsperlong.h |   9 +-
>  arch/arm64/include/uapi/asm/siginfo.h     |  21 +++
>  arch/arm64/include/uapi/asm/signal.h      |  31 +++++
>  arch/arm64/kernel/Makefile                |   4 +-
>  arch/arm64/kernel/asm-offsets.c           |   2 +-
>  arch/arm64/kernel/entry.S                 |  18 ++-
>  arch/arm64/kernel/entry32-common.S        |  37 +++++
>  arch/arm64/kernel/entry32.S               |  29 ----
>  arch/arm64/kernel/head.S                  |   2 +-
>  arch/arm64/kernel/hw_breakpoint.c         |   7 +-
>  arch/arm64/kernel/perf_regs.c             |   2 +-
>  arch/arm64/kernel/process.c               |   4 +-
>  arch/arm64/kernel/ptrace.c                |  47 ++++---
>  arch/arm64/kernel/signal.c                |  21 ++-
>  arch/arm64/kernel/sys_ilp32.c             | 223 ++++++++++++++++++++++++++++++
>  arch/arm64/kernel/traps.c                 |   4 +-
>  arch/arm64/kernel/vdso.c                  |  12 +-
>  include/linux/compat.h                    |   4 +
>  include/uapi/asm-generic/siginfo.h        |  17 ++-
>  include/uapi/asm-generic/signal.h         |  27 +++-
>  kernel/ptrace.c                           |  24 +++-
>  35 files changed, 745 insertions(+), 110 deletions(-)
>  create mode 100644 Documentation/arm64/ilp32.txt
>  create mode 100644 arch/arm64/kernel/entry32-common.S
>  create mode 100644 arch/arm64/kernel/sys_ilp32.c
>