Re: [patch 1/1] kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union initialization bug

[David Miller]

From: a...@linux-foundation.org
Date: Mon, 18 Jul 2016 15:50:58 -0700

> From: Andrew Morton 
> Subject: kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union 
> initialization bug
> 
> kernel/trace/bpf_trace.c: In function 'bpf_event_output':
> kernel/trace/bpf_trace.c:312: error: unknown field 'next' specified in 
> initializer
> kernel/trace/bpf_trace.c:312: warning: missing braces around initializer
> kernel/trace/bpf_trace.c:312: warning: (near initialization for 
> 'raw.frag.')
> 
> Fixes: 555c8a8623a3a87 ("bpf: avoid stack copy and use skb ctx for event 
> output")
> Acked-by: Daniel Borkmann 
> Cc: Alexei Starovoitov 
> Cc: David S. Miller 
> Signed-off-by: Andrew Morton 

Applied.

Re: [patch 1/1] kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union initialization bug

[Daniel Borkmann]

On 07/19/2016 05:07 AM, Fengguang Wu wrote:

On Mon, Jul 18, 2016 at 07:38:27PM -0700, Alexei Starovoitov wrote:

On Tue, Jul 19, 2016 at 08:38:02AM +0800, Fengguang Wu wrote:

On Mon, Jul 18, 2016 at 05:33:07PM -0700, Alexei Starovoitov wrote:

[...]

>Fengguang can you add gcc-4.4 to buildbot. Thanks!

Sure. Currently we only test gcc-6. It'd be easy to test more versions
concurrently, like

gcc-4.4
gcc-4.6
gcc-4.8
gcc-4.9
gcc-5
gcc-6


thanks! If you need to reduce the test matrix I don't see a concern
of dropping 4.6 and 4.8.
4.4 is good for old stuff, 4.9 is the most stable and 5/6 are good
for new warnings.


Not a burden at all. I've enabled them all. :)


Nice, thanks a lot Fengguang!

Re: [patch 1/1] kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union initialization bug

[Fengguang Wu]

On Mon, Jul 18, 2016 at 07:38:27PM -0700, Alexei Starovoitov wrote:

On Tue, Jul 19, 2016 at 08:38:02AM +0800, Fengguang Wu wrote:

Hi Alexei,

On Mon, Jul 18, 2016 at 05:33:07PM -0700, Alexei Starovoitov wrote:
>On Mon, Jul 18, 2016 at 03:50:58PM -0700, a...@linux-foundation.org wrote:
>>From: Andrew Morton 
>>Subject: kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union 
initialization bug
>>
>>kernel/trace/bpf_trace.c: In function 'bpf_event_output':
>>kernel/trace/bpf_trace.c:312: error: unknown field 'next' specified in 
initializer
>>kernel/trace/bpf_trace.c:312: warning: missing braces around initializer
>>kernel/trace/bpf_trace.c:312: warning: (near initialization for 
'raw.frag.')
>>
>>Fixes: 555c8a8623a3a87 ("bpf: avoid stack copy and use skb ctx for event 
output")
>>Acked-by: Daniel Borkmann 
>>Cc: Alexei Starovoitov 
>>Cc: David S. Miller 
>>Signed-off-by: Andrew Morton 
>
>Acked-by: Alexei Starovoitov 
>
>Fengguang can you add gcc-4.4 to buildbot. Thanks!

Sure. Currently we only test gcc-6. It'd be easy to test more versions
concurrently, like

gcc-4.4
gcc-4.6
gcc-4.8
gcc-4.9
gcc-5
gcc-6


thanks! If you need to reduce the test matrix I don't see a concern
of dropping 4.6 and 4.8.
4.4 is good for old stuff, 4.9 is the most stable and 5/6 are good
for new warnings.


Not a burden at all. I've enabled them all. :)

Thanks,
Fengguang

Re: [patch 1/1] kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union initialization bug

[Alexei Starovoitov]

On Tue, Jul 19, 2016 at 08:38:02AM +0800, Fengguang Wu wrote:
> Hi Alexei,
> 
> On Mon, Jul 18, 2016 at 05:33:07PM -0700, Alexei Starovoitov wrote:
> >On Mon, Jul 18, 2016 at 03:50:58PM -0700, a...@linux-foundation.org wrote:
> >>From: Andrew Morton 
> >>Subject: kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union 
> >>initialization bug
> >>
> >>kernel/trace/bpf_trace.c: In function 'bpf_event_output':
> >>kernel/trace/bpf_trace.c:312: error: unknown field 'next' specified in 
> >>initializer
> >>kernel/trace/bpf_trace.c:312: warning: missing braces around initializer
> >>kernel/trace/bpf_trace.c:312: warning: (near initialization for 
> >>'raw.frag.')
> >>
> >>Fixes: 555c8a8623a3a87 ("bpf: avoid stack copy and use skb ctx for event 
> >>output")
> >>Acked-by: Daniel Borkmann 
> >>Cc: Alexei Starovoitov 
> >>Cc: David S. Miller 
> >>Signed-off-by: Andrew Morton 
> >
> >Acked-by: Alexei Starovoitov 
> >
> >Fengguang can you add gcc-4.4 to buildbot. Thanks!
> 
> Sure. Currently we only test gcc-6. It'd be easy to test more versions
> concurrently, like
> 
> gcc-4.4
> gcc-4.6
> gcc-4.8
> gcc-4.9
> gcc-5
> gcc-6

thanks! If you need to reduce the test matrix I don't see a concern
of dropping 4.6 and 4.8.
4.4 is good for old stuff, 4.9 is the most stable and 5/6 are good
for new warnings.

Re: [patch 1/1] kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union initialization bug

[Fengguang Wu]

Hi Alexei,

On Mon, Jul 18, 2016 at 05:33:07PM -0700, Alexei Starovoitov wrote:

On Mon, Jul 18, 2016 at 03:50:58PM -0700, a...@linux-foundation.org wrote:

From: Andrew Morton 
Subject: kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union 
initialization bug

kernel/trace/bpf_trace.c: In function 'bpf_event_output':
kernel/trace/bpf_trace.c:312: error: unknown field 'next' specified in 
initializer
kernel/trace/bpf_trace.c:312: warning: missing braces around initializer
kernel/trace/bpf_trace.c:312: warning: (near initialization for 
'raw.frag.')

Fixes: 555c8a8623a3a87 ("bpf: avoid stack copy and use skb ctx for event 
output")
Acked-by: Daniel Borkmann 
Cc: Alexei Starovoitov 
Cc: David S. Miller 
Signed-off-by: Andrew Morton 


Acked-by: Alexei Starovoitov 

Fengguang can you add gcc-4.4 to buildbot. Thanks!


Sure. Currently we only test gcc-6. It'd be easy to test more versions
concurrently, like

gcc-4.4
gcc-4.6
gcc-4.8
gcc-4.9
gcc-5
gcc-6

Thanks,
Fengguang

Re: [patch 1/1] kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union initialization bug

[Alexei Starovoitov]

On Mon, Jul 18, 2016 at 03:50:58PM -0700, a...@linux-foundation.org wrote:
> From: Andrew Morton 
> Subject: kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union 
> initialization bug
> 
> kernel/trace/bpf_trace.c: In function 'bpf_event_output':
> kernel/trace/bpf_trace.c:312: error: unknown field 'next' specified in 
> initializer
> kernel/trace/bpf_trace.c:312: warning: missing braces around initializer
> kernel/trace/bpf_trace.c:312: warning: (near initialization for 
> 'raw.frag.')
> 
> Fixes: 555c8a8623a3a87 ("bpf: avoid stack copy and use skb ctx for event 
> output")
> Acked-by: Daniel Borkmann 
> Cc: Alexei Starovoitov 
> Cc: David S. Miller 
> Signed-off-by: Andrew Morton 

Acked-by: Alexei Starovoitov 

Fengguang can you add gcc-4.4 to buildbot. Thanks!

[patch 1/1] kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union initialization bug

[akpm]

From: Andrew Morton 
Subject: kernel/trace/bpf_trace.c: work around gcc-4.4.4 anon union 
initialization bug

kernel/trace/bpf_trace.c: In function 'bpf_event_output':
kernel/trace/bpf_trace.c:312: error: unknown field 'next' specified in 
initializer
kernel/trace/bpf_trace.c:312: warning: missing braces around initializer
kernel/trace/bpf_trace.c:312: warning: (near initialization for 
'raw.frag.')

Fixes: 555c8a8623a3a87 ("bpf: avoid stack copy and use skb ctx for event 
output")
Acked-by: Daniel Borkmann 
Cc: Alexei Starovoitov 
Cc: David S. Miller 
Signed-off-by: Andrew Morton 
---

 kernel/trace/bpf_trace.c |4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff -puN 
kernel/trace/bpf_trace.c~kernel-trace-bpf_tracec-work-around-gcc-444-anon-union-initialization-bug
 kernel/trace/bpf_trace.c
--- 
a/kernel/trace/bpf_trace.c~kernel-trace-bpf_tracec-work-around-gcc-444-anon-union-initialization-bug
+++ a/kernel/trace/bpf_trace.c
@@ -309,7 +309,9 @@ u64 bpf_event_output(struct bpf_map *map
};
struct perf_raw_record raw = {
.frag = {
-   .next   = ctx_size ? &frag : NULL,
+   {
+   .next   = ctx_size ? &frag : NULL,
+   },
.size   = meta_size,
.data   = meta,
},
_