systemtap for hwe kernels

[Impact]

systemtap includes some kernel code compiled at runtime every time a stap script is executed. This means that running a different kernel with different ABIs may break systemtap. This is exactly what happens with the hwe kernel.

We need to provide a separate systemtap package (systemtap-hwe for example) that can be installed together with the hwe kernel.

For example on xenial, ideally, we may want to backport systemtap from bionic and call it systemtap-hwe, similarly to what we're doing with the kernel.

[Test Case]

For example, this is what happens in xenial with the hwe kernel installed (linux-image-generic-hwe-16.04):

$ cat /home/ubuntu/hello.stp
#!/usr/bin/env stap
probe oneshot { println("hello world") }

$ sudo /home/ubuntu/hello.stp
In file included from /usr/share/systemtap/runtime/linux/runtime.h:204:0,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_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:24:8: error: implicit declaration of function ‘get_task_mm’ [-Werror=implicit-function-declaration]
   mm = get_task_mm (tsk);
        ^
/usr/share/systemtap/runtime/linux/access_process_vm.h:24:6: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
   mm = get_task_mm (tsk);
      ^
/usr/share/systemtap/runtime/linux/access_process_vm.h:35:29: error: passing argument 1 of ‘get_user_pages’ makes integer from pointer without a cast [-Werror=int-conversion]
       ret = get_user_pages (tsk, mm, addr, 1, write, 1, &page, &vma);
                             ^
In file included from ./include/linux/pid_namespace.h:7:0,
                 from ./include/linux/ptrace.h:10,
                 from ./include/linux/ftrace.h:14,
                 from ./include/linux/kprobes.h:42,
                 from /usr/share/systemtap/runtime/linux/runtime.h:21,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:25:
./include/linux/mm.h:1398:6: note: expected ‘long unsigned int’ but argument is of type ‘struct task_struct *’
 long get_user_pages(unsigned long start, unsigned long nr_pages,
      ^
In file included from /usr/share/systemtap/runtime/linux/runtime.h:204:0,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:25:
/usr/share/systemtap/runtime/linux/access_process_vm.h:35:34: error: passing argument 2 of ‘get_user_pages’ makes integer from pointer without a cast [-Werror=int-conversion]
       ret = get_user_pages (tsk, mm, addr, 1, write, 1, &page, &vma);
                                  ^
In file included from ./include/linux/pid_namespace.h:7:0,
                 from ./include/linux/ptrace.h:10,
                 from ./include/linux/ftrace.h:14,
                 from ./include/linux/kprobes.h:42,
                 from /usr/share/systemtap/runtime/linux/runtime.h:21,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:25:
./include/linux/mm.h:1398:6: note: expected ‘long unsigned int’ but argument is of type ‘struct mm_struct *’
 long get_user_pages(unsigned long start, unsigned long nr_pages,
      ^
In file included from /usr/share/systemtap/runtime/linux/runtime.h:204:0,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:25:
/usr/share/systemtap/runtime/linux/access_process_vm.h:35:44: error: passing argument 4 of ‘get_user_pages’ makes pointer from integer without a cast [-Werror=int-conversion]
       ret = get_user_pages (tsk, mm, addr, 1, write, 1, &page, &vma);
                                            ^
In file included from ./include/linux/pid_namespace.h:7:0,
                 from ./include/linux/ptrace.h:10,
                 from ./include/linux/ftrace.h:14,
                 from ./include/linux/kprobes.h:42,
                 from /usr/share/systemtap/runtime/linux/runtime.h:21,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:25:
./include/linux/mm.h:1398:6: note: expected ‘struct page **’ but argument is of type ‘int’
 long get_user_pages(unsigned long start, unsigned long nr_pages,
      ^
In file included from /usr/share/systemtap/runtime/linux/runtime.h:204:0,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:25:
/usr/share/systemtap/runtime/linux/access_process_vm.h:35:47: error: passing argument 5 of ‘get_user_pages’ makes pointer from integer without a cast [-Werror=int-conversion]
       ret = get_user_pages (tsk, mm, addr, 1, write, 1, &page, &vma);
                                               ^
In file included from ./include/linux/pid_namespace.h:7:0,
                 from ./include/linux/ptrace.h:10,
                 from ./include/linux/ftrace.h:14,
                 from ./include/linux/kprobes.h:42,
                 from /usr/share/systemtap/runtime/linux/runtime.h:21,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:25:
./include/linux/mm.h:1398:6: note: expected ‘struct vm_area_struct **’ but argument is of type ‘int’
 long get_user_pages(unsigned long start, unsigned long nr_pages,
      ^
In file included from /usr/share/systemtap/runtime/linux/runtime.h:204:0,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:25:
/usr/share/systemtap/runtime/linux/access_process_vm.h:35:13: 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:7:0,
                 from ./include/linux/ptrace.h:10,
                 from ./include/linux/ftrace.h:14,
                 from ./include/linux/kprobes.h:42,
                 from /usr/share/systemtap/runtime/linux/runtime.h:21,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:25:
./include/linux/mm.h:1398:6: note: declared here
 long get_user_pages(unsigned long start, unsigned long nr_pages,
      ^
In file included from /usr/share/systemtap/runtime/linux/runtime.h:204:0,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:25:
/usr/share/systemtap/runtime/linux/access_process_vm.h:55:7: error: implicit declaration of function ‘page_cache_release’ [-Werror=implicit-function-declaration]
       page_cache_release (page);
       ^
/usr/share/systemtap/runtime/linux/access_process_vm.h:61:3: error: implicit declaration of function ‘mmput’ [-Werror=implicit-function-declaration]
   mmput (mm);
   ^
In file included from /usr/share/systemtap/runtime/stp_utrace.c:30:0,
                 from /usr/share/systemtap/runtime/linux/task_finder2.c:4,
                 from /usr/share/systemtap/runtime/linux/task_finder.c:17,
                 from /usr/share/systemtap/runtime/linux/runtime.h:217,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:25:
/usr/share/systemtap/runtime/stp_helper_lock.h: In function ‘stp_spin_unlock_wait’:
/usr/share/systemtap/runtime/stp_helper_lock.h:60:61: error: implicit declaration of function ‘spin_unlock_wait’ [-Werror=implicit-function-declaration]
 static inline void stp_spin_unlock_wait(spinlock_t *lock) { spin_unlock_wait(lock); }
                                                             ^
In file included from /usr/share/systemtap/runtime/linux/task_finder2.c:4:0,
                 from /usr/share/systemtap/runtime/linux/task_finder.c:17,
                 from /usr/share/systemtap/runtime/linux/runtime.h:217,
                 from /usr/share/systemtap/runtime/runtime.h:24,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:25:
/usr/share/systemtap/runtime/stp_utrace.c: In function ‘utrace_do_stop’:
/usr/share/systemtap/runtime/stp_utrace.c:1095:4: error: implicit declaration of function ‘__set_task_state’ [-Werror=implicit-function-declaration]
    __set_task_state(target, TASK_TRACED);
    ^
In file included from /usr/share/systemtap/runtime/transport/transport.c:68:0,
                 from /usr/share/systemtap/runtime/linux/print.c:17,
                 from /usr/share/systemtap/runtime/print.c:17,
                 from /usr/share/systemtap/runtime/runtime_context.h:22,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:55:
/usr/share/systemtap/runtime/transport/relay_v2.c: In function ‘__stp_relay_timer_init’:
/usr/share/systemtap/runtime/transport/relay_v2.c:147:2: error: implicit declaration of function ‘init_timer’ [-Werror=implicit-function-declaration]
  init_timer(&_stp_relay_data.timer);
  ^
/usr/share/systemtap/runtime/transport/relay_v2.c:149:33: error: assignment from incompatible pointer type [-Werror=incompatible-pointer-types]
  _stp_relay_data.timer.function = __stp_relay_wakeup_timer;
                                 ^
/usr/share/systemtap/runtime/transport/relay_v2.c:150:23: error: ‘struct timer_list’ has no member named ‘data’
  _stp_relay_data.timer.data = 0;
                       ^
In file included from /usr/share/systemtap/runtime/linux/print.c:17:0,
                 from /usr/share/systemtap/runtime/print.c:17,
                 from /usr/share/systemtap/runtime/runtime_context.h:22,
                 from /tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.c:55:
/usr/share/systemtap/runtime/transport/transport.c: In function ‘_stp_attach’:
/usr/share/systemtap/runtime/transport/transport.c:324:31: error: assignment from incompatible pointer type [-Werror=incompatible-pointer-types]
  _stp_ctl_work_timer.function = _stp_ctl_work_callback;
                               ^
/usr/share/systemtap/runtime/transport/transport.c:325:21: error: ‘struct timer_list’ has no member named ‘data’
  _stp_ctl_work_timer.data= 0;
                     ^
/usr/share/systemtap/runtime/transport/transport.c: In function ‘_stp_lock_inode’:
/usr/share/systemtap/runtime/transport/transport.c:506:19: error: ‘struct inode’ has no member named ‘i_mutex’
  mutex_lock(&inode->i_mutex);
                   ^
/usr/share/systemtap/runtime/transport/transport.c: In function ‘_stp_unlock_inode’:
/usr/share/systemtap/runtime/transport/transport.c:515:21: error: ‘struct inode’ has no member named ‘i_mutex’
  mutex_unlock(&inode->i_mutex);
                     ^
cc1: all warnings being treated as errors
scripts/Makefile.build:330: recipe for target '/tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.o' failed
make[1]: *** [/tmp/stapCmbcrm/stap_e18a9aff18b91b2a0f0570b0096c64b1_967_src.o] Error 1
Makefile:1552: recipe for target '_module_/tmp/stapCmbcrm' failed
make: *** [_module_/tmp/stapCmbcrm] Error 2
WARNING: kbuild exited with status: 2
Pass 4: compilation failed. [man error::pass4]
Tip: /usr/share/doc/systemtap/README.Debian should help you get started.