Re: [kbuild-all] [vhost:vhost 19/20] Warning: arch/x86/tools/test_get_len found difference at :ffffffff811aa5f0

[Philip Li]

On Thu, Feb 08, 2018 at 01:25:39AM +0100, Daniel Borkmann wrote:
> On 02/08/2018 01:20 AM, Philip Li wrote:
> > On Thu, Feb 08, 2018 at 02:09:41AM +0200, Michael S. Tsirkin wrote:
> >> On Wed, Feb 07, 2018 at 03:02:57PM +0800, kbuild test robot wrote:
> >>> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git 
> >>> vhost
> >>> head:   96bcd04462b99e2c80e09f6537770a0ca6b288d0
> >>> commit: cc1d1dc07885803981520a5303ef5b130f2ca2e8 [19/20] mm: support 
> >>> reporting free page blocks
> >>> config: x86_64-rhel
> >>> compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
> >>> reproduce:
> >>> git checkout cc1d1dc07885803981520a5303ef5b130f2ca2e8
> >>> # save the attached .config to linux build tree
> >>> make ARCH=x86_64 
> >>>
> >>> All warnings (new ones prefixed by >>):
> >>
> >> I'm sorry, what exactly does this mean?
> > sorry that the script has issue to provide empty warnings here, which
> > was supposed to list warnings with >> added to new ones like below.
> > 
> >In file included from kernel//bpf/core.c:29:0:
> >>> include/linux/bpf.h:72:8: error: duplicate member 'security'
> >  void *security;
> >^
> > 
> > We will follow up to check what goes wrong.
> 
> Certainly odd, even in that tree/commit/header [0] I cannot see a duplicate
> security member in struct bpf_map.
that is one example i try to show what looks like for the >> prefix, and i copy
it from https://lists.01.org/pipermail/kbuild-all/2018-February/042706.html, 
which
is not for vhost repo.

Here for this report, the issue is as title "Warning: 
arch/x86/tools/test_get_len found difference at 
:811aa5f0".

> 
>   [0] 
> https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git/tree/include/linux/bpf.h?h=vhost=cc1d1dc07885803981520a5303ef5b130f2ca2e8#n45

Re: [kbuild-all] [vhost:vhost 19/20] Warning: arch/x86/tools/test_get_len found difference at :ffffffff811aa5f0

[Philip Li]

On Thu, Feb 08, 2018 at 02:09:41AM +0200, Michael S. Tsirkin wrote:
> On Wed, Feb 07, 2018 at 03:02:57PM +0800, kbuild test robot wrote:
> > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git vhost
> > head:   96bcd04462b99e2c80e09f6537770a0ca6b288d0
> > commit: cc1d1dc07885803981520a5303ef5b130f2ca2e8 [19/20] mm: support 
> > reporting free page blocks
> > config: x86_64-rhel
> > compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
> > reproduce:
> > git checkout cc1d1dc07885803981520a5303ef5b130f2ca2e8
> > # save the attached .config to linux build tree
> > make ARCH=x86_64 
> > 
> > All warnings (new ones prefixed by >>):
> 
> I'm sorry, what exactly does this mean?
sorry that the script has issue to provide empty warnings here, which
was supposed to list warnings with >> added to new ones like below.

   In file included from kernel//bpf/core.c:29:0:
>> include/linux/bpf.h:72:8: error: duplicate member 'security'
 void *security;
   ^

We will follow up to check what goes wrong.

> 
> > ---
> > 0-DAY kernel test infrastructureOpen Source Technology 
> > Center
> > https://lists.01.org/pipermail/kbuild-all   Intel 
> > Corporation
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Re: [PATCH] bpf: avoid warning for wrong pointer cast

[Philip Li]

On Tue, Apr 19, 2016 at 10:33:34AM +0800, Fengguang Wu wrote:
> Hi Alexei,
> 
> On Sat, Apr 16, 2016 at 05:47:42PM -0700, Alexei Starovoitov wrote:
> > On Sat, Apr 16, 2016 at 10:29:33PM +0200, Arnd Bergmann wrote:
> > > Two new functions in bpf contain a cast from a 'u64' to a
> > > pointer. This works on 64-bit architectures but causes a warning
> > > on all 32-bit architectures:
> > > 
> > > kernel/trace/bpf_trace.c: In function 'bpf_perf_event_output_tp':
> > > kernel/trace/bpf_trace.c:350:13: error: cast to pointer from integer of 
> > > different size [-Werror=int-to-pointer-cast]
> > >   u64 ctx = *(long *)r1;
> > > 
> > > This changes the cast to first convert the u64 argument into a uintptr_t,
> > > which is guaranteed to be the same size as a pointer.
> > > 
> > > Signed-off-by: Arnd Bergmann 
> > > Fixes: 9940d67c93b5 ("bpf: support bpf_get_stackid() and 
> > > bpf_perf_event_output() in tracepoint programs")
> > 
> > Thanks.
> > Acked-by: Alexei Starovoitov 
> > 
> > I guess I started to rely on 0-day build-bot too much.
> > This patch has been in my tree for 2+ weeks and then in net-next and
> > I didn't receive a single email from build-bot about this warning,
> > though I do receive them for my other work-in-progress stuff. Odd.
> > Fengguang, any idea why build-bot sometimes silent?
> 
> Sorry I went off for some time.. Philip, would you help have a check?
Hi Alexei, i have done some investigation for this. Fengguang, pls correct me 
if my understanding is wrong.

0day has caught the warning for f1ff54 commit around 2016-3-22, which considers 
the same warning in future is not new one, thus neglect it.

rli9@inn /kbuild-tests/build-error$ cat 
kernel-trace-bpf_trace.c:warning:cast-to-pointer-from-integer-of-different-size
kernel/trace/bpf_trace.c:345:13: warning: cast to pointer from integer 
of different size [-Wint-to-pointer-cast]

2016-03-22 17:12:38 xian 
bpf:master:321e70e79c94e5e6394a882d567baac949b74000 i386-randconfig-x009-201612 
f1ff543dbdd3eff53c8328cfb582f18e6c3d56ec

And for f1ff54's warning, 0day actually bisects to it, but then it checks the 
head of bpf/master at that time which is 321e70e, find the error is not 
existed, so
it ignores the interim warning to not send email report.

2016-03-22_17:15:49 O: R: /kbuild/src/consumer/kernel/trace/bpf_trace.c:345:13: 
warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
2016-03-22_17:15:49 O: grep -h -r . 
/tmp/kernel/i386-randconfig-x009-201612/gcc-5/f1ff543dbdd3eff53c8328cfb582f18e6c3d56ec/build-error
 # 0 errors 
2016-03-22_17:15:49 O: grep -h -r . 
/tmp/kernel/i386-randconfig-x009-201612/gcc-5/f1ff543dbdd3eff53c8328cfb582f18e6c3d56ec/build-error/
 # 0 errors 
2016-03-22_17:15:49 O: /c/kernel-tests/list-head 
bpf:master:321e70e79c94e5e6394a882d567baac949b74000 i386-randconfig-x009-201612 
2016-03-22_17:16:03 O: .
2016-03-22_17:16:03 O: ..
2016-03-22_17:16:03 O: 
kernel-trace-bpf_trace.c:warning:cast-to-pointer-from-integer-of-different-size
2016-03-22_17:16:03 O: 2016-03-22 17:16:03 don't email interim warnings
2016-03-22_17:16:03 O: 2016-03-22 17:16:03 error no longer exist in head 
bpf/master 321e70e79c94e5e6394a882d567baac949b74000, check 
/tmp/kernel/i386-randconfig-x009-201612/gcc-5/321e70e79c94e5e6394a882d567baac949b74000,
 errno 14
2016-03-22_17:16:03 O: 2016-03-22 17:16:03 Don't email interim warnings!


what really happens to 321e70e is it has build error (i rerun it to confirm), 
which is reported at 
https://lists.01.org/pipermail/kbuild-all/2016-March/018625.html. So this is
a possible change to be done in 0day to report the first bad commit when HEAD 
is build error.

2016-04-19_15:00:39 O: 2016-04-19 15:00  Running 
/kbuild-tests/build-queue/lkp-nex06-consumer/i386-randconfig-x009-201612-gcc-5-321e70e79c94e5e6394a882d567baac949b74000
2016-04-19_15:00:39 O: create new KBUILD_OUTPUT dir 
/kbuild/obj/consumer/i386-randconfig-x009-201612
2016-04-19_15:00:39 O: git checkout -B build-queue 
321e70e79c94e5e6394a882d567baac949b74000
2016-04-19_15:07:08 E: 330 real  4732 user  629 sys  1620.50% cpu   
i386-randconfig-x009-201612
2016-04-19_15:07:13 O: status: FAIL: build error
2016-04-19_15:07:13 O: ERROR: "tcp_sendpage" 
[drivers/staging/lustre/lnet/klnds/socklnd/ksocklnd.ko] undefined!

> 
> Thanks,
> Fengguang