[lttng-dev] [PATCH] lttng-modules: Fixes for ARM and 32-bit systems

[Trent Piepho]

On Mon, 2017-03-06 at 17:12 +0000, Mathieu Desnoyers wrote:
> ----- On Mar 3, 2017, at 6:43 PM, Trent Piepho tpiepho at kymetacorp.com wrote:
> 
> Hi Trent,
> 
> What lttng-modules branch is this for ?

Sorry about this, I meant to send this patch to the *buildroot* list to
fix the bugs in the current version of lttng that's part of buildroot.
It's non-obviously but significantly broken on 32-bit ARM systems and I
wanted to get it fixed before the next version of lttng-modules is
released.  Not sure how I got the address incorrect.  

> > Patch to fix recv() syscall missing in ARM syscall list.
> 
> This was probably missing because the current ARM syscall instrumentation
> was generated from a 3.4.25 kernel that was missing SYSCALL macro
> description of those system calls. The proper route would be to
> regenerate the system call table by running a more recent kernel
> and following instrumentation/syscalls/README from lttng-modules.

My most recent available ARM system uses 3.18.0, if a patch for that
kernel is desirable, I'll submit one.  But it sounded like a newer 4.x
kernel was wanted and I don't have such a system.  

This was meant to be sent to buildroot as a bug fix until a proper fix
was came from upstream lttng.  Usually when a distro does patching to
fix some cross-build issue or something like that, one prefers to fix on
the side of "minimal changes" instead of "best fix".  Less trouble
porting that way.  That's why I didn't add 3.18 and made the smaller
patch to fix the 3.4.25 descriptions. 


> > Patch from lttng mailing list that fixes kernel timestamps being off
> > by about ~2 seconds on 32-bit systems.  Additional patch to fix
> > compilation bug on non-X86 introduced by previous patch.
> 
> Why are you re-posting an old version of own patch which now merged
> into master, stable-2.9 and stable-2.8 branches of lttng-modules ?

I didn't know there was a new version, as I didn't see a followup on the
thread about the original.  I'll send the newer patch from stable-2.9 to
buildroot instead of this one then.

Apologies again for sending this to the wrong list.