sparc32: Make no sendmsg/recvmsg syscalls for older Linux kernels than 4.4

Message ID 1478504615-11054-1-git-send-email-andreas@gaisler.com
State New, archived
Headers

Commit Message

Andreas Larsson Nov. 7, 2016, 7:43 a.m. UTC
  The sendmsg and recvmsg systems calls were not available for 32-bit
sparc Linux kernels before Linux kernel version 4.4.

	* sysdeps/unix/sysv/linux/sparc/kernel-features.h: Undefine
	__ASSUME_SENDMSG_SYSCALL and __ASSUME_RECVMSG_SYSCALL for 32-bit
	sparc for older Linux kernels than 4.4.
---
 sysdeps/unix/sysv/linux/sparc/kernel-features.h | 5 +++++
 1 file changed, 5 insertions(+)
  

Comments

Joseph Myers Nov. 7, 2016, 3:48 p.m. UTC | #1
On Mon, 7 Nov 2016, Andreas Larsson wrote:

> The sendmsg and recvmsg systems calls were not available for 32-bit
> sparc Linux kernels before Linux kernel version 4.4.

Given the conditional you are putting this under: should I take it it is 
specifically for 32-bit kernels and the system calls *are* available for 
32-bit binaries executed under 64-bit kernels?
  
Andreas Larsson Nov. 8, 2016, 2:20 p.m. UTC | #2
On 2016-11-07 16:48, Joseph Myers wrote:
> On Mon, 7 Nov 2016, Andreas Larsson wrote:
>
>> The sendmsg and recvmsg systems calls were not available for 32-bit
>> sparc Linux kernels before Linux kernel version 4.4.
>
> Given the conditional you are putting this under: should I take it it is
> specifically for 32-bit kernels and the system calls *are* available for
> 32-bit binaries executed under 64-bit kernels?

Yes, the intention is specifically for 32-bit kernels. This patch makes 
interfacing older 32-bit kernels work.

The system calls are available in 64-bit kernels since before Linux 3.2. 
I don't have the possibility to test the case with 32-bit binaries under 
a 64-bit kernel, so I don't want to touch the behavior for that case.

Best regards,
Andreas Larsson
  
David Miller Nov. 8, 2016, 4:31 p.m. UTC | #3
From: Andreas Larsson <andreas@gaisler.com>
Date: Tue, 08 Nov 2016 15:20:30 +0100

> On 2016-11-07 16:48, Joseph Myers wrote:
>> On Mon, 7 Nov 2016, Andreas Larsson wrote:
>>
>>> The sendmsg and recvmsg systems calls were not available for 32-bit
>>> sparc Linux kernels before Linux kernel version 4.4.
>>
>> Given the conditional you are putting this under: should I take it it
>> is
>> specifically for 32-bit kernels and the system calls *are* available
>> for
>> 32-bit binaries executed under 64-bit kernels?
> 
> Yes, the intention is specifically for 32-bit kernels. This patch
> makes interfacing older 32-bit kernels work.
> 
> The system calls are available in 64-bit kernels since before Linux
> 3.2. I don't have the possibility to test the case with 32-bit
> binaries under a 64-bit kernel, so I don't want to touch the behavior
> for that case.

The same commit in the kernel added them to all of the 32-bit cases
(native and running under 64-bit kernel) so you can safely assume
they exist universally starting with 4.4
  

Patch

diff --git a/sysdeps/unix/sysv/linux/sparc/kernel-features.h b/sysdeps/unix/sysv/linux/sparc/kernel-features.h
index 69c9c7c..b7a79a7 100644
--- a/sysdeps/unix/sysv/linux/sparc/kernel-features.h
+++ b/sysdeps/unix/sysv/linux/sparc/kernel-features.h
@@ -36,4 +36,9 @@ 
 #if !defined __arch64__ && !defined __sparc_v9__
 # undef __ASSUME_REQUEUE_PI
 # undef __ASSUME_SET_ROBUST_LIST
+/* All direct socketcalls are available only with kernel 4.4.  */
+# if __LINUX_KERNEL_VERSION < 0x040400
+#  undef __ASSUME_SENDMSG_SYSCALL
+#  undef __ASSUME_RECVMSG_SYSCALL
+# endif
 #endif