Re: Systemtap is broken on latest ElRepo LT kernels (4.4.x)

[Kirill Borodin <kirill at ivinco dot com>]

Hi Hou!

Thanks, patch works fine for 4.0 systemtap and for both el6/el7 lt-kernels!

I think we need ping ElRepo with this patch, but they support only 3.3
version AFAIK

Thanks again Hou!

On Fri, Feb 1, 2019 at 2:35 PM Hou Tao <houtao1@huawei.com> wrote:

> Hi,
>
> On 2019/2/1 17:38, Kirill Borodin wrote:
> > Hi, All!
> >
> > I've tried all systemtap versions 3.x and 4.x for ELRepo LT-kernels,
> latest
> > kernels are not supported, for example 4.4.169, 4.4.172 (last one) but it
> > is working on 4.4.145 !
> >
> > If it's known bug, please, point me to the thread
> That's because commit 768ae309a961 ("mm: replace get_user_pages()
> write/force parameters with gup_flags")
> is back-ported to linux-stable-4.4 (the corresponding commit is
> 8e50b8b07f46), and it changes the function
> signature of get_user_pages() as showed in the following diff-stat:
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 5c18cd9c72d2..d1cfd3657cce 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -1199,7 +1199,7 @@ long __get_user_pages(struct task_struct *tsk,
> struct mm_struct *mm,
>                       struct vm_area_struct **vmas, int *nonblocking);
>  long get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
>                     unsigned long start, unsigned long nr_pages,
> -                   int write, int force, struct page **pages,
> +                   unsigned int gup_flags, struct page **pages,
>                     struct vm_area_struct **vmas);
>  long get_user_pages_locked(struct task_struct *tsk, struct mm_struct *mm,
>                     unsigned long start, unsigned long nr_pages,
>
> Could you please try the attached patch for Systemtap ?
>
> Regards,
> Tao
> >
> > I've builded systemtap on the same machines where I trying to use it and
> > got following errors:
> >
> > # stap -ve 'probe begin { log("hello world") exit () }' 2>&1 | less
> >
> >
> > Pass 1: parsed user script and 483 library scripts using
> > 275600virt/76472res/6872shr/69832data kb, in 650usr/30sys/688real ms.
> >
> > Pass 2: analyzed script: 1 probe, 2 functions, 0 embeds, 0 globals using
> > 277184virt/78116res/6944shr/71416data kb, in 10usr/0sys/9real ms.
> >
> > Pass 3: translated to C into
> > "/tmp/stap38hdTg/stap_4937637228108ffaaea1709160cfed96_1147_src.c" using
> > 277316virt/79084res/7828shr/71548data kb, in 0usr/0sys/0real ms.
> >
> > In file included from /usr/share/systemtap/runtime/linux/runtime.h:214:0,
> >
> >                  from /usr/share/systemtap/runtime/runtime.h:26,
> >
> >                  from
> > /tmp/stap38hdTg/stap_4937637228108ffaaea1709160cfed96_1147_src.c:25:
> >
> > /usr/share/systemtap/runtime/linux/access_process_vm.h: In function
> > ‘__access_process_vm_’:
> >
> > /usr/share/systemtap/runtime/linux/access_process_vm.h:54:7: error:
> passing
> > argument 6 of ‘get_user_pages’ makes pointer from integer without a cast
> > [-Werror]
> >
> >        ret = get_user_pages (tsk, mm, addr, 1, write, 1, &page, &vma);
> >
> >        ^
> >> In file included from include/linux/pid_namespace.h:6:0,
> >
> >                  from include/linux/ptrace.h:8,
> >
> >                  from include/linux/ftrace.h:13,
> >
> >                  from include/linux/kprobes.h:42,
> >
> >                  from /usr/share/systemtap/runtime/linux/runtime.h:21,
> >
> >                  from /usr/share/systemtap/runtime/runtime.h:26,
> >
> >                  from
> > /tmp/stap38hdTg/stap_4937637228108ffaaea1709160cfed96_1147_src.c:25:
> >
> > include/linux/mm.h:1200:6: note: expected ‘struct page **’ but argument
> is
> > of type ‘int’
> >
> >  long get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
> >
> >       ^
> >
> > In file included from /usr/share/systemtap/runtime/linux/runtime.h:214:0,
> >
> >                  from /usr/share/systemtap/runtime/runtime.h:26,
> >
> >                  from
> > /tmp/stap38hdTg/stap_4937637228108ffaaea1709160cfed96_1147_src.c:25:
> >
> > /usr/share/systemtap/runtime/linux/access_process_vm.h:54:7: error:
> passing
> > argument 7 of ‘get_user_pages’ from incompatible pointer type [-Werror]
> >
> >        ret = get_user_pages (tsk, mm, addr, 1, write, 1, &page, &vma);
> >
> >        ^
> >
> > In file included from include/linux/pid_namespace.h:6:0,
> >
> >                  from include/linux/ptrace.h:8,
> >
> >                  from include/linux/ftrace.h:13,
> >
> >                  from include/linux/kprobes.h:42,
> >
> >                  from /usr/share/systemtap/runtime/linux/runtime.h:21,
> >
> >                  from /usr/share/systemtap/runtime/runtime.h:26,
> >
> >                  from
> > /tmp/stap38hdTg/stap_4937637228108ffaaea1709160cfed96_1147_src.c:25:
> >
> > include/linux/mm.h:1200:6: note: expected ‘struct vm_area_struct **’ but
> > argument is of type ‘struct page **’
> >
> >  long get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
> >
> >       ^
> >
> > In file included from /usr/share/systemtap/runtime/linux/runtime.h:214:0,
> >
> >                  from /usr/share/systemtap/runtime/runtime.h:26,
> >
> >                  from
> > /tmp/stap38hdTg/stap_4937637228108ffaaea1709160cfed96_1147_src.c:25:
> >
> > /usr/share/systemtap/runtime/linux/access_process_vm.h:54:7: error: too
> > many arguments to function ‘get_user_pages’
> >
> >        ret = get_user_pages (tsk, mm, addr, 1, write, 1, &page, &vma);
> >
> >        ^
> >
> > In file included from include/linux/pid_namespace.h:6:0,
> >
> >                  from include/linux/ptrace.h:8,
> >
> >                  from include/linux/ftrace.h:13,
> >
> >                  from include/linux/kprobes.h:42,
> >
> >                  from /usr/share/systemtap/runtime/linux/runtime.h:21,
> >
> >                  from /usr/share/systemtap/runtime/runtime.h:26,
> >
> >                  from
> > /tmp/stap38hdTg/stap_4937637228108ffaaea1709160cfed96_1147_src.c:25:
> >
> > include/linux/mm.h:1200:6: note: declared here
> >
> >  long get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
> >
> >       ^
> >
> > /tmp/stap38hdTg/stap_4937637228108ffaaea1709160cfed96_1147_src.c: At top
> > level:
> >
> > cc1: error: unrecognized command line option "-Wno-tautological-compare"
> > [-Werror]
> >
> > cc1: all warnings being treated as errors
> >
> > make[1]: ***
> > [/tmp/stap38hdTg/stap_4937637228108ffaaea1709160cfed96_1147_src.o] Error
> 1
> >
> > make: *** [_module_/tmp/stap38hdTg] Error 2
> >
> > WARNING: kbuild exited with status: 2
> >
> > Pass 4: compiled C into "stap_4937637228108ffaaea1709160cfed96_1147.ko"
> in
> > 8030usr/1810sys/9721real ms.
> >
> > Pass 4: compilation failed.  [man error::pass4]
> >
> > Thanks!
> >
> > .
> >
>