mainlining shenanigans
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Arnaldo Carvalho de Melo 4b1303d0b0 perf symbols: Accept zero as the kernel base address
Which is the case in S/390, where symbols were not being resolved
because machine__get_kernel_start was only setting machine->kernel_start
when the just successfully loaded kernel symtab had its map->start set
to !0, when it was left at (1ULL << 63) assuming a partitioning of the
address space for user/kernel, which is not the case in S/390 nor in
Sparc.

So just check if map__load() was successfull and set
machine->kernel_start to zero, fixing kernel symbol resolution on S/390.

Test performed by Thomas:

 ----

  I like this patch. I have done a new build and removed all my debug output to start
  from scratch. Without your patch I get this:

  # Samples: 4  of event 'cpu-clock'
  # Event count (approx.): 1000000
  #
  # Children      Self  Command  Shared Object     Symbol
  # ........  ........  .......  ................  ........................
      75.00%     0.00%  true     [unknown]         [k] 0x00000000004bedda
              |
              ---0x4bedda
                 |
                 |--50.00%--0x42693a
                 |          |
                 |           --25.00%--0x2a72e0
                 |                     0x2af0ca
                 |                     0x3d1003fe4c0
                 |
                  --25.00%--0x4272bc
                            0x26fa84

  and with your patch (I just rebuilt the perf tool, nothing else and used the same
  perf.data file as input):

  # Samples: 4  of event 'cpu-clock'
  # Event count (approx.): 1000000
  #
  # Children      Self  Command  Shared Object               Symbol
  # ........  ........  .......  ..........................  ..................................
      75.00%     0.00%  true     [kernel.vmlinux]            [k] pgm_check_handler
              |
              ---pgm_check_handler
                 do_dat_exception
                 handle_mm_fault
                 __handle_mm_fault
                 filemap_map_pages
                 |
                 |--25.00%--rcu_read_lock_held
                 |          rcu_lockdep_current_cpu_online
                 |          0x3d1003ff4c0
                 |
                  --25.00%--lock_release

  Looks good to me....
 ----

Reported-and-Tested-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com>
Link: http://lkml.kernel.org/n/tip-dk0n1uzmbe0tbthrpfqlx6bz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-07-12 11:47:05 -03:00
arch kprobes: Rename [arch_]function_offset_within_entry() to [arch_]kprobe_on_func_entry() 2017-07-08 11:05:34 +02:00
block Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 16:50:31 -07:00
certs scripts/spelling.txt: add "intialise(d)" pattern and fix typo instances 2017-05-08 17:15:13 -07:00
crypto crypto : asymmetric_keys : verify_pefile:zero memory content before freeing 2017-06-09 13:29:50 +10:00
Documentation Merge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 18:33:03 -07:00
drivers Merge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 18:33:03 -07:00
firmware firmware/Makefile: force recompilation if makefile changes 2017-05-08 17:15:10 -07:00
fs Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 13:08:04 -07:00
include kprobes: Rename [arch_]function_offset_within_entry() to [arch_]kprobe_on_func_entry() 2017-07-08 11:05:34 +02:00
init Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 13:08:04 -07:00
ipc mm: introduce kv[mz]alloc helpers 2017-05-08 17:15:12 -07:00
kernel Revert "perf/core: Drop kernel samples even though :u is specified" 2017-07-11 10:56:54 +02:00
lib Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 13:08:04 -07:00
mm Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 14:45:09 -07:00
net Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 13:08:04 -07:00
samples samples/bpf: run cleanup routines when receiving SIGTERM 2017-05-11 21:43:30 -04:00
scripts Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 11:34:53 -07:00
security Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 13:08:04 -07:00
sound Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 13:08:04 -07:00
tools perf symbols: Accept zero as the kernel base address 2017-07-12 11:47:05 -03:00
usr initramfs: fix disabling of initramfs (and its compression) 2017-06-02 15:07:37 -07:00
virt sched/wait: Rename wait_queue_t => wait_queue_entry_t 2017-06-20 12:18:27 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: Add support to generate LLVM assembly files 2017-04-25 08:13:52 +09:00
.mailmap power supply and reset changes for the v4.12 series (part 2) 2017-05-12 12:02:21 -07:00
COPYING
CREDITS avr32: remove support for AVR32 architecture 2017-05-01 09:27:15 +02:00
Kbuild kbuild: Consolidate header generation from ASM offset information 2017-04-13 05:43:37 +09:00
Kconfig
MAINTAINERS Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-03 12:14:18 -07:00
Makefile Linux 4.12 2017-07-02 16:07:02 -07:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.