Re: Update kernel-features.h files for Linux 5.1

[Stepan Golosunov <stepan at golosunov dot pp dot ru>]

09.05.2019 в 23:00:37 +0000 Joseph Myers написал:
> Linux 5.1 adds missing syscalls to the syscall table for many Linux
> kernel architectures.  This patch updates the kernel-features.h
> headers accordingly.  I believe the statfs64 structure used by alpha
> matches what the new kernel syscalls use, but that should be reviewed
> carefully.
> 
> Tested with build-many-glibcs.py.

The newly added direct ipc syscalls are different from the old ones:

1. They do not accept IPC_64.  This means that __IPC_64 should be set
to zero when new syscalls are used.  And new syscalls can not be used
for compat functions like __old_semctl.

(Hmm.  Is __old_msgctl already buggy due to its use of __IPC_64 when
__ASSUME_DIRECT_SYSVIPC_SYSCALLS is defined?  Is there any
architecture with both __ASSUME_DIRECT_SYSVIPC_SYSCALLS and
__old_msgctl currently?)

2. semtimedop does not exist on 32-bit ABIs.  They have
semtimedop_time64 instead.
(I also think that ipc with IPCOP_semtimedop was accidentally made to
behave like semtimedop_time64 in 32-bit builds of linux 5.1.  But that
would be a kernel bug.)

> diff --git a/sysdeps/unix/sysv/linux/i386/kernel-features.h b/sysdeps/unix/sysv/linux/i386/kernel-features.h
> index 3ac725b5a2..8610651346 100644
> --- a/sysdeps/unix/sysv/linux/i386/kernel-features.h
> +++ b/sysdeps/unix/sysv/linux/i386/kernel-features.h
> @@ -43,8 +43,10 @@
>  # undef __ASSUME_SENDTO_SYSCALL
>  #endif
>  
> -/* i686 only supports ipc syscall.  */
> -#undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +/* i686 only supports ipc syscall before 5.1.  */
> +#if __LINUX_KERNEL_VERSION < 0x050100
> +# undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +#endif
>  
>  #undef __ASSUME_CLONE_DEFAULT
>  #define __ASSUME_CLONE_BACKWARDS	1

> diff --git a/sysdeps/unix/sysv/linux/m68k/kernel-features.h b/sysdeps/unix/sysv/linux/m68k/kernel-features.h
> index 1976724362..1467474b8a 100644
> --- a/sysdeps/unix/sysv/linux/m68k/kernel-features.h
> +++ b/sysdeps/unix/sysv/linux/m68k/kernel-features.h
> @@ -50,5 +50,7 @@
>  # undef __ASSUME_SET_ROBUST_LIST
>  #endif
>  
> -/* m68k only supports ipc syscall.  */
> -#undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +/* m68k only supports ipc syscall before 5.1.  */
> +#if __LINUX_KERNEL_VERSION < 0x050100
> +# undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +#endif
> diff --git a/sysdeps/unix/sysv/linux/mips/kernel-features.h b/sysdeps/unix/sysv/linux/mips/kernel-features.h
> index c341c3fa10..8114090913 100644
> --- a/sysdeps/unix/sysv/linux/mips/kernel-features.h
> +++ b/sysdeps/unix/sysv/linux/mips/kernel-features.h
> @@ -31,8 +31,10 @@
>     pairs to start with an even-number register.  */
>  #if _MIPS_SIM == _ABIO32
>  # define __ASSUME_ALIGNED_REGISTER_PAIRS	1
> -/* mips32 only supports ipc syscall.  */
> -# undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +/* mips32 only supports ipc syscall before 5.1.  */
> +# if __LINUX_KERNEL_VERSION < 0x050100
> +#  undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +# endif
>  
>  /* The o32 MIPS fadvise64 syscall behaves as fadvise64_64.  */
>  # define __ASSUME_FADVISE64_AS_64_64		1
> diff --git a/sysdeps/unix/sysv/linux/powerpc/kernel-features.h b/sysdeps/unix/sysv/linux/powerpc/kernel-features.h
> index 413a185db3..5924534c22 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/kernel-features.h
> +++ b/sysdeps/unix/sysv/linux/powerpc/kernel-features.h
> @@ -44,8 +44,10 @@
>  
>  #include_next <kernel-features.h>
>  
> -/* powerpc only supports ipc syscall.  */
> -#undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +/* powerpc only supports ipc syscall before 5.1.  */
> +#if __LINUX_KERNEL_VERSION < 0x050100
> +# undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +#endif
>  
>  #undef __ASSUME_CLONE_DEFAULT
>  #define __ASSUME_CLONE_BACKWARDS	1
> diff --git a/sysdeps/unix/sysv/linux/s390/kernel-features.h b/sysdeps/unix/sysv/linux/s390/kernel-features.h
> index 8fdf38c454..dcbf1c7c53 100644
> --- a/sysdeps/unix/sysv/linux/s390/kernel-features.h
> +++ b/sysdeps/unix/sysv/linux/s390/kernel-features.h
> @@ -45,8 +45,10 @@
>  # undef __ASSUME_SENDTO_SYSCALL
>  #endif
>  
> -/* s390 only supports ipc syscall.  */
> -#undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +/* s390 only supports ipc syscall before 5.1.  */
> +#if __LINUX_KERNEL_VERSION < 0x050100
> +# undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +#endif
>  
>  #undef __ASSUME_CLONE_DEFAULT
>  #define __ASSUME_CLONE_BACKWARDS2
> diff --git a/sysdeps/unix/sysv/linux/sh/kernel-features.h b/sysdeps/unix/sysv/linux/sh/kernel-features.h
> index 767df721b8..8532cccadd 100644
> --- a/sysdeps/unix/sysv/linux/sh/kernel-features.h
> +++ b/sysdeps/unix/sysv/linux/sh/kernel-features.h
> @@ -41,8 +41,10 @@
>     before the offset.  */
>  #define __ASSUME_PRW_DUMMY_ARG	1
>  
> -/* sh only supports ipc syscall.  */
> -#undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +/* sh only supports ipc syscall before 5.1.  */
> +#if __LINUX_KERNEL_VERSION < 0x050100
> +# undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +#endif
>  
>  /* Support for several syscalls was added in 4.8.  */
>  #if __LINUX_KERNEL_VERSION < 0x040800

> diff --git a/sysdeps/unix/sysv/linux/sparc/kernel-features.h b/sysdeps/unix/sysv/linux/sparc/kernel-features.h
> index f441bd811d..7b5db4af17 100644
> --- a/sysdeps/unix/sysv/linux/sparc/kernel-features.h
> +++ b/sysdeps/unix/sysv/linux/sparc/kernel-features.h
> @@ -58,8 +58,10 @@
>  # undef __NR_pause
>  #endif
>  
> -/* sparc only supports ipc syscall.  */
> -#undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +/* sparc only supports ipc syscall before 5.1.  */
> +#if __LINUX_KERNEL_VERSION < 0x050100
> +# undef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
> +#endif
>  
>  /* Support for the renameat2 syscall was added in 3.16.  */
>  #if __LINUX_KERNEL_VERSION < 0x031000