Commit Graph

296 Commits

Author SHA1 Message Date
Masahiro Yamada d503ac531a kbuild: rename LDFLAGS to KBUILD_LDFLAGS
Commit a0f97e06a4 ("kbuild: enable 'make CFLAGS=...' to add
additional options to CC") renamed CFLAGS to KBUILD_CFLAGS.

Commit 222d394d30 ("kbuild: enable 'make AFLAGS=...' to add
additional options to AS") renamed AFLAGS to KBUILD_AFLAGS.

Commit 06c5040cdb ("kbuild: enable 'make CPPFLAGS=...' to add
additional options to CPP") renamed CPPFLAGS to KBUILD_CPPFLAGS.

For some reason, LDFLAGS was not renamed.

Using a well-known variable like LDFLAGS may result in accidental
override of the variable.

Kbuild generally uses KBUILD_ prefixed variables for the internally
appended options, so here is one more conversion to sanitize the
naming convention.

I did not touch Makefiles under tools/ since the tools build system
is a different world.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-24 08:22:08 +09:00
Masahiro Yamada 87a32e6240 kbuild: pass LDFLAGS to recordmcount.pl
Since commit 0fbe9a245c ("microblaze: add endianness options to
LDFLAGS instead of LD"), you cannot build the kernel for microblaze
with CONFIG_DYNAMIC_FTRACE.

Fixes: 0fbe9a245c ("microblaze: add endianness options to LDFLAGS instead of LD")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-24 08:22:08 +09:00
Linus Torvalds 7140ad3898 Updates for v4.19:
- Restructure of lockdep and latency tracers
 
    This is the biggest change. Joel Fernandes restructured the hooks
    from irqs and preemption disabling and enabling. He got rid of
    a lot of the preprocessor #ifdef mess that they caused.
 
    He turned both lockdep and the latency tracers to use trace events
    inserted in the preempt/irqs disabling paths. But unfortunately,
    these started to cause issues in corner cases. Thus, parts of the
    code was reverted back to where lockde and the latency tracers
    just get called directly (without using the trace events).
    But because the original change cleaned up the code very nicely
    we kept that, as well as the trace events for preempt and irqs
    disabling, but they are limited to not being called in NMIs.
 
  - Have trace events use SRCU for "rcu idle" calls. This was required
    for the preempt/irqs off trace events. But it also had to not
    allow them to be called in NMI context. Waiting till Paul makes
    an NMI safe SRCU API.
 
  - New notrace SRCU API to allow trace events to use SRCU.
 
  - Addition of mcount-nop option support
 
  - SPDX headers replacing GPL templates.
 
  - Various other fixes and clean ups.
 
  - Some fixes are marked for stable, but were not fully tested
    before the merge window opened.
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCW3ruhRQccm9zdGVkdEBn
 b29kbWlzLm9yZwAKCRAp5XQQmuv6qiM7AP47NhYdSnCFCRUJfrt6PovXmQtuCHt3
 c3QMoGGdvzh9YAEAqcSXwh7uLhpHUp1LjMAPkXdZVwNddf4zJQ1zyxQ+EAU=
 =vgEr
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - Restructure of lockdep and latency tracers

   This is the biggest change. Joel Fernandes restructured the hooks
   from irqs and preemption disabling and enabling. He got rid of a lot
   of the preprocessor #ifdef mess that they caused.

   He turned both lockdep and the latency tracers to use trace events
   inserted in the preempt/irqs disabling paths. But unfortunately,
   these started to cause issues in corner cases. Thus, parts of the
   code was reverted back to where lockdep and the latency tracers just
   get called directly (without using the trace events). But because the
   original change cleaned up the code very nicely we kept that, as well
   as the trace events for preempt and irqs disabling, but they are
   limited to not being called in NMIs.

 - Have trace events use SRCU for "rcu idle" calls. This was required
   for the preempt/irqs off trace events. But it also had to not allow
   them to be called in NMI context. Waiting till Paul makes an NMI safe
   SRCU API.

 - New notrace SRCU API to allow trace events to use SRCU.

 - Addition of mcount-nop option support

 - SPDX headers replacing GPL templates.

 - Various other fixes and clean ups.

 - Some fixes are marked for stable, but were not fully tested before
   the merge window opened.

* tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits)
  tracing: Fix SPDX format headers to use C++ style comments
  tracing: Add SPDX License format tags to tracing files
  tracing: Add SPDX License format to bpf_trace.c
  blktrace: Add SPDX License format header
  s390/ftrace: Add -mfentry and -mnop-mcount support
  tracing: Add -mcount-nop option support
  tracing: Avoid calling cc-option -mrecord-mcount for every Makefile
  tracing: Handle CC_FLAGS_FTRACE more accurately
  Uprobe: Additional argument arch_uprobe to uprobe_write_opcode()
  Uprobes: Simplify uprobe_register() body
  tracepoints: Free early tracepoints after RCU is initialized
  uprobes: Use synchronize_rcu() not synchronize_sched()
  tracing: Fix synchronizing to event changes with tracepoint_synchronize_unregister()
  ftrace: Remove unused pointer ftrace_swapper_pid
  tracing: More reverting of "tracing: Centralize preemptirq tracepoints and unify their usage"
  tracing/irqsoff: Handle preempt_count for different configs
  tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and unify their usage"
  tracing: irqsoff: Account for additional preempt_disable
  trace: Use rcu_dereference_raw for hooks from trace-event subsystem
  tracing/kprobes: Fix within_notrace_func() to check only notrace functions
  ...
2018-08-20 18:32:00 -07:00
Vasily Gorbik 07d0408120 tracing: Avoid calling cc-option -mrecord-mcount for every Makefile
Currently if CONFIG_FTRACE_MCOUNT_RECORD is enabled -mrecord-mcount
compiler flag support is tested for every Makefile.

Top 4 cc-option usages:
    511 -mrecord-mcount
     11  -fno-stack-protector
      9 -Wno-override-init
      2 -fsched-pressure

To address that move cc-option from scripts/Makefile.build to top Makefile
and export CC_USING_RECORD_MCOUNT to be used in original place.

While doing that also add -mrecord-mcount to CC_FLAGS_FTRACE (if gcc
actually supports it).

Link: http://lkml.kernel.org/r/patch-2.thread-aa7b8d.git-de935bace15a.your-ad-here.call-01533557518-ext-9465@work.hours

Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-15 22:37:22 -04:00
Masahiro Yamada d6c6ab93e1 kbuild: remove deprecated host-progs variable
The host-progs has been kept as an alias of hostprogs-y for a long time
(at least since the beginning of Git era), with the clear prompt:
  Usage of host-progs is deprecated. Please replace with hostprogs-y!

Enough time for the migration has passed.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
2018-08-09 21:51:17 +09:00
Masahiro Yamada 6916162c73 kbuild: remove duplicated comments about PHONY
The comment is the same as in the top-level Makefile.

Also, the comments contain typos:
  - the .PHONY variable  ->  the PHONY variable
  - se we can ...        ->  so we can ...

Instead of fixing the typos, just remove the duplicated comments.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-06 22:04:03 +09:00
Greg Thelen ed7d40bc67 tracing: Fix SKIP_STACK_VALIDATION=1 build due to bad merge with -mrecord-mcount
Non gcc-5 builds with CONFIG_STACK_VALIDATION=y and
SKIP_STACK_VALIDATION=1 fail.
Example output:
  /bin/sh: init/.tmp_main.o: Permission denied

commit 96f60dfa58 ("trace: Use -mcount-record for dynamic ftrace"),
added a mismatched endif.  This causes cmd_objtool to get mistakenly
set.

Relocate endif to balance the newly added -record-mcount check.

Link: http://lkml.kernel.org/r/20180608214746.136554-1-gthelen@google.com

Fixes: 96f60dfa58 ("trace: Use -mcount-record for dynamic ftrace")
Acked-by: Andi Kleen <ak@linux.intel.com>
Tested-by: David Rientjes <rientjes@google.com>
Signed-off-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-06-21 15:12:56 -04:00
Linus Torvalds 5eb6eed7e0 One new feature was added to ftrace, which is the trace_marker now supports
triggers. For example:
 
   # cd /sys/kernel/debug/tracing
   # echo 'snapshot' > events/ftrace/print/trigger
   # echo 'cause snapshot' > trace_marker
 
 The rest of the changes are various clean ups and also one stable fix that
 was added late in the cycle.
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCWxftjBQccm9zdGVkdEBn
 b29kbWlzLm9yZwAKCRAp5XQQmuv6qosyAQCgmhb+/HgRYIbsKa8Q70E2pMx5A/za
 4rQ37Q9PhDUJlAD/aWXfrqcMm+buAU0yY4K+eb+f2feKXWXxdZ/fuh7+nA4=
 =lpXM
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "One new feature was added to ftrace, which is the trace_marker now
  supports triggers. For example:

    # cd /sys/kernel/debug/tracing
    # echo 'snapshot' > events/ftrace/print/trigger
    # echo 'cause snapshot' > trace_marker

  The rest of the changes are various clean ups and also one stable fix
  that was added late in the cycle"

* tag 'trace-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (21 commits)
  tracing: Use match_string() instead of open coding it in trace_set_options()
  branch-check: fix long->int truncation when profiling branches
  ring-buffer: Fix typo in comment
  ring-buffer: Fix a bunch of typos in comments
  tracing/selftest: Add test to test simple snapshot trigger for trace_marker
  tracing/selftest: Add test to test hist trigger between kernel event and trace_marker
  tracing/selftest: Add selftests to test trace_marker histogram triggers
  ftrace/selftest: Fix reset_trigger() to handle triggers with filters
  ftrace/selftest: Have the reset_trigger code be a bit more careful
  tracing: Document trace_marker triggers
  tracing: Allow histogram triggers to access ftrace internal events
  tracing: Prevent further users of zero size static arrays in trace events
  tracing: Have zero size length in filter logic be full string
  tracing: Add trigger file for trace_markers tracefs/ftrace/print
  tracing: Do not show filter file for ftrace internal events
  tracing: Add brackets in ftrace event dynamic arrays
  tracing: Have event_trace_init() called by trace_init_tracefs()
  tracing: Add __find_event_file() to find event files without restrictions
  tracing: Do not reference event data in post call triggers
  tracepoints: Fix the descriptions of tracepoint_probe_register{_prio}
  ...
2018-06-06 16:39:18 -07:00
Andi Kleen 96f60dfa58 trace: Use -mcount-record for dynamic ftrace
gcc 5 supports a new -mcount-record option to generate ftrace
tables directly. This avoids the need to run record_mcount
manually.

Use this option when available.

So far doesn't use -mcount-nop, which also exists now.

This is needed to make ftrace work with LTO because the
normal record-mcount script doesn't run over the link
time output.

It should also improve build times slightly in the general
case.
Link: http://lkml.kernel.org/r/20171127213423.27218-12-andi@firstfloor.org

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-28 12:49:51 -04:00
Masahiro Yamada 704db5433f kbuild: remove CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX was selected by BLACKFIN, METAG.
They were removed by commit 4ba66a9760 ("arch: remove blackfin port"),
commit bb6fb6dfcc ("metag: Remove arch/metag/"), respectively.

No more architecture enables CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX.
Clean up the rest of scripts, and remove the Kconfig entry.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
2018-05-17 22:44:57 +09:00
Masahiro Yamada 74d9317161 genksyms: remove symbol prefix support
CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX was selected by BLACKFIN, METAG.
They were removed by commit 4ba66a9760 ("arch: remove blackfin port"),
commit bb6fb6dfcc ("metag: Remove arch/metag/"), respectively.

No more architecture enables CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX,
hence the -s (--symbol-prefix) option is unnecessary.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
2018-05-17 22:43:35 +09:00
Masahiro Yamada 54a702f705 kbuild: mark $(targets) as .SECONDARY and remove .PRECIOUS markers
GNU Make automatically deletes intermediate files that are updated
in a chain of pattern rules.

Example 1) %.dtb.o <- %.dtb.S <- %.dtb <- %.dts
Example 2) %.o <- %.c <- %.c_shipped

A couple of makefiles mark such targets as .PRECIOUS to prevent Make
from deleting them, but the correct way is to use .SECONDARY.

  .SECONDARY
    Prerequisites of this special target are treated as intermediate
    files but are never automatically deleted.

  .PRECIOUS
    When make is interrupted during execution, it may delete the target
    file it is updating if the file was modified since make started.
    If you mark the file as precious, make will never delete the file
    if interrupted.

Both can avoid deletion of intermediate files, but the difference is
the behavior when Make is interrupted; .SECONDARY deletes the target,
but .PRECIOUS does not.

The use of .PRECIOUS is relatively rare since we do not want to keep
partially constructed (possibly corrupted) targets.

Another difference is that .PRECIOUS works with pattern rules whereas
.SECONDARY does not.

  .PRECIOUS: $(obj)/%.lex.c

works, but

  .SECONDARY: $(obj)/%.lex.c

has no effect.  However, for the reason above, I do not want to use
.PRECIOUS which could cause obscure build breakage.

The targets specified as .SECONDARY must be explicit.  $(targets)
contains all targets that need to include .*.cmd files.  So, the
intermediates you want to keep are mostly in there.  Therefore, mark
$(targets) as .SECONDARY.  It means primary targets are also marked
as .SECONDARY, but I do not see any drawback for this.

I replaced some .SECONDARY / .PRECIOUS markers with 'targets'.  This
will make Kbuild search for non-existing .*.cmd files, but this is
not a noticeable performance issue.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Frank Rowand <frowand.list@gmail.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
2018-04-07 19:04:02 +09:00
Masahiro Yamada 4fa8bc949d kbuild: rename *-asn1.[ch] to *.asn1.[ch]
Our convention is to distinguish file types by suffixes with a period
as a separator.

*-asn1.[ch] is a different pattern from other generated sources such
as *.lex.c, *.tab.[ch], *.dtb.S, etc.  More confusing, files with
'-asn1.[ch]' are generated files, but '_asn1.[ch]' are checked-in
files:
  net/netfilter/nf_conntrack_h323_asn1.c
  include/linux/netfilter/nf_conntrack_h323_asn1.h
  include/linux/sunrpc/gss_asn1.h

Rename generated files to *.asn1.[ch] for consistency.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-04-07 19:04:02 +09:00
Masahiro Yamada a7f9241909 kbuild: add %.dtb.S and %.dtb to 'targets' automatically
Another common pattern that consists of chained commands is to compile
a DTB as binary data into the kernel image or a module.  It is used in
several places in the source tree.  Support it in the core Makefile.

$(call if_changed,dt_S_dtb) is more suitable than $(call cmd,dt_S_dtb)
in case cmd_dt_S_dtb is changed in the future.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Frank Rowand <frowand.list@gmail.com>
2018-04-07 19:04:02 +09:00
Masahiro Yamada b23d1a241f kbuild: add %.lex.c and %.tab.[ch] to 'targets' automatically
Files generated by if_changed* must be added to 'targets' to include
*.cmd files.  Otherwise, they would be regenerated every time.

The build system automatically adds objects to 'targets' where
appropriate, such as obj-y, extra-y, etc. but does nothing for
intermediate files.  So, each Makefile needs to add them by itself.

There are some common cases where objects are generated by chained
rules.  Lexers and parsers are compiled like follows:

   %.lex.o <- %.lex.c <- %.l
   %.tab.o <- %.tab.c <- %.y

They are common patterns, so it is reasonable to take care of them
in the core Makefile instead of requiring each Makefile to do so.

At this moment, you cannot delete 'target += zconf.lex.c' in the
Kconfig Makefile because zconf.lex.c is included from zconf.tab.c
instead of being compiled separately.  It should be deleted after
Kconfig is more refactored.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Frank Rowand <frowand.list@gmail.com>
2018-04-07 19:04:02 +09:00
Masahiro Yamada 127668cf76 kbuild: clean up link rule of composite modules
cmd_link_multi-link is used only for cmd_link_multi-m.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:01:29 +09:00
Masahiro Yamada 5e18f0290f kbuild: clean up archive rule of built-in.a
With the incremental linking entirely dropped, we can simplify
the Makefile.

While I am here, I renamed cmd_link_o_target to cmd_ar_builtin.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:01:28 +09:00
Masahiro Yamada 7657f60e8f kbuild: remove partial section mismatch detection for built-in.a
When built-in.o was incrementally linked with 'ld -r', the section
mismatch analysis for the individual built-in.o was possible when
CONFIG_DEBUG_SECTION_MISMATCH was enabled.

With the migration to the thin archive, built-in.a (former, built-in.o)
is no longer an ELF file.  So, the modpost does nothing useful.
scripts/mod/modpost.c just checks the header to bail out, as follows:

        /* Is this a valid ELF file? */
        if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
            (hdr->e_ident[EI_MAG1] != ELFMAG1) ||
            (hdr->e_ident[EI_MAG2] != ELFMAG2) ||
            (hdr->e_ident[EI_MAG3] != ELFMAG3)) {
                /* Not an ELF file - silently ignore it */
                return 0;
        }

We have the full analysis in the final link stage anyway, so we would
not miss the section mismatching.

I do not see a good reason to require extra linking only for the
purpose of the per-directory analysis.  Just get rid of this part.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:01:28 +09:00
Masahiro Yamada f98fe47ce5 kbuild: link $(real-obj-y) instead of $(obj-y) into built-in.a
In Kbuild, Makefiles can add the same object to obj-y multiple
times.  So,

   obj-y += foo.o
   obj-y += foo.o

is fine.

However, this is not true when the same object is added multiple
times via composite objects.  For example,

   obj-y    += foo.o bar.o
   foo-objs := foo-bar-common.o foo-only.o
   bar-objs := foo-bar-common.o bar-only.o

causes build error because two instances of foo-bar-common.o are
linked into the vmlinux.

Makefiles tend to invent ugly work-around, for example
  - lib/zstd/Makefile
  - drivers/net/ethernet/cavium/liquidio/Makefile

The technique used in Kbuild to avoid the multiple definition error
is to use $(filter $(obj-y), $^).  Here, $^ lists the names of all
the prerequisites with duplicated names removed.

By replacing it with $(filter $(real-obj-y), $^) we can do likewise
for composite objects.  For built-in objects, we do not need to keep
the composite object structure.  We can simply expand them, and link
$(real-obj-y) to built-in.a.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:01:27 +09:00
Masahiro Yamada f5f336812c kbuild: rename real-objs-y/m to real-obj-y/m
When I was refactoring Makefiles, I stupidly mistook 'real-obj-y' for
'real-objs-y' over and over again.  Finally, I decide to rename it to
'real-obj-y'.  This is consistent with 'obj-y', 'subdir-obj-y'.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:01:26 +09:00
Masahiro Yamada c0152e9a6b kbuild: move modname and modname-multi close to modname_flags
Just a cosmetic change to put related code close together.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Cao jin <caoj.fnst@cn.fujitsu.com>
2018-03-26 02:01:26 +09:00
Masahiro Yamada fe852ac200 kbuild: simplify modname calculation
modname can be calculated much more simply.  If modname-multi is
empty, it is a single-used object.  So, modname = $(basetarget).
Otherwise, modname = $(modname-multi).

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Cao jin <caoj.fnst@cn.fujitsu.com>
2018-03-26 02:01:25 +09:00
Nicholas Piggin f49821ee32 kbuild: rename built-in.o to built-in.a
Incremental linking is gone, so rename built-in.o to built-in.a, which
is the usual extension for archive files.

This patch does two things, first is a simple search/replace:

git grep -l 'built-in\.o' | xargs sed -i 's/built-in\.o/built-in\.a/g'

The second is to invert nesting of nested text manipulations to avoid
filtering built-in.a out from libs-y2:

-libs-y2 := $(filter-out %.a, $(patsubst %/, %/built-in.a, $(libs-y)))
+libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:01:19 +09:00
Nicholas Piggin 6358d6e8b9 kbuild: remove incremental linking option
This removes the old `ld -r` incremental link option, which has not
been selected by any architecture since June 2017.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:01:19 +09:00
Michael Forney 1fe7d2bb24 kbuild: Improve portability of some sed invocations
* Use BREs where EREs aren't necessary.
* Pass -E instead of -r to use EREs. This will be standardized in the
  next POSIX revision[0]. GNU sed supports this since 4.2 (May 2009),
  and busybox since 1.22.0 (Jan 2014).
* Use the [:space:] character class instead of ` \t` in bracket
  expressions. In bracket expressions, POSIX says that <backslash> loses
  its special meaning, so a conforming implementation cannot expand \t
  to <tab>[1].
* In BREs, use interval expressions (\{n,m\}) instead of non-standard
  features like \+ and \?.
* Use a loop instead of -s flag.

There are still plenty of other cases of non-standard sed invocations
(use of ERE features in BREs, in-place editing), but this fixes some
core ones.

[0] http://austingroupbugs.net/view.php?id=528
[1] http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html#tag_09_03_05

Signed-off-by: Michael Forney <forney@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:01:18 +09:00
Peter Zijlstra d5028ba8ee objtool, retpolines: Integrate objtool with retpoline support more closely
Disable retpoline validation in objtool if your compiler sucks, and otherwise
select the validation stuff for CONFIG_RETPOLINE=y (most builds would already
have it set due to ORC).

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-21 16:54:32 +01:00
Peter Zijlstra ca41b97ed9 objtool: Add module specific retpoline rules
David allowed retpolines in .init.text, except for modules, which will
trip up objtool retpoline validation, fix that.

Requested-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-21 09:05:05 +01:00
Peter Zijlstra b5bc2231b8 objtool: Add retpoline validation
David requested a objtool validation pass for CONFIG_RETPOLINE=y enabled
builds, where it validates no unannotated indirect  jumps or calls are
left.

Add an additional .discard.retpoline_safe section to allow annotating
the few indirect sites that are required and safe.

Requested-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-21 09:05:04 +01:00
Linus Torvalds 88dc7fca18 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 pti bits and fixes from Thomas Gleixner:
 "This last update contains:

   - An objtool fix to prevent a segfault with the gold linker by
     changing the invocation order. That's not just for gold, it's a
     general robustness improvement.

   - An improved error message for objtool which spares tearing hairs.

   - Make KASAN fail loudly if there is not enough memory instead of
     oopsing at some random place later

   - RSB fill on context switch to prevent RSB underflow and speculation
     through other units.

   - Make the retpoline/RSB functionality work reliably for both Intel
     and AMD

   - Add retpoline to the module version magic so mismatch can be
     detected

   - A small (non-fix) update for cpufeatures which prevents cpu feature
     clashing for the upcoming extra mitigation bits to ease
     backporting"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  module: Add retpoline tag to VERMAGIC
  x86/cpufeature: Move processor tracing out of scattered features
  objtool: Improve error message for bad file argument
  objtool: Fix seg fault with gold linker
  x86/retpoline: Add LFENCE to the retpoline/RSB filling RSB macros
  x86/retpoline: Fill RSB on context switch for affected CPUs
  x86/kasan: Panic if there is not enough memory to boot
2018-01-17 11:54:56 -08:00
Josh Poimboeuf 2a0098d706 objtool: Fix seg fault with gold linker
Objtool segfaults when the gold linker is used with
CONFIG_MODVERSIONS=y and CONFIG_UNWINDER_ORC=y.

With CONFIG_MODVERSIONS=y, the .o file gets passed to the linker before
being passed to objtool.  The gold linker seems to strip unused ELF
symbols by default, which confuses objtool and causes the seg fault when
it's trying to generate ORC metadata.

Objtool should really be running immediately after GCC anyway, without a
linker call in between.  Change the makefile ordering so that objtool is
called before the linker.

Reported-and-tested-by: Markus <M4rkusXXL@web.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: ee9f8fce99 ("x86/unwind: Add the ORC unwinder")
Link: http://lkml.kernel.org/r/355f04da33581f4a3bf82e5b512973624a1e23a2.1516025651.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16 01:27:27 +01:00
Ingo Molnar 0fd2e9c53d Merge commit 'upstream-x86-entry' into WIP.x86/mm
Pull in a minimal set of v4.15 entry code changes, for a base for the MM isolation patches.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-17 12:58:53 +01:00
Linus Torvalds 5e2fda4776 Kbuild updates for v4.15 (2nd)
- Use pwd instead of /bin/pwd for portability
 
 - Clean up Makefiles
 
 - Fix ld-option for clang
 
 - Fix malloc'ed data size in Kconfig
 
 - Fix parallel building along with coccicheck
 
 - Fix a minor issue of package building
 
 - Prompt to use "rpm-pkg" instead of "rpm"
 
 - Clean up *.i and *.lst patterns by "make clean"
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJaGEuYAAoJED2LAQed4NsG1H8P/1cKSZk7G9tA1L7DndvoTNLz
 oc+wM7dUQ3NBndBsyymGe3/cvmlPoB6tam5otAyHaDjBsiGL6pQAeCi1RjJ24aMO
 BHb3vUWLh7GiGnIpe9uMNYIghuRpHdK53rkh9uPaKXmLZBSHtOdd81wHlZGsUdyY
 6U2HHUM6c6KiueTYuULiP2wXE6u0YhREjb5MUL6SThAoME0tDaf7JnWguo7sKJAv
 CUlw9196LoDtj/2VRN3Rd9baGefqDw05PYqUZ9RWfCcl/h8gm7Xo9jW8THRLTIj5
 hRbqNRDHEBjN0QY1FFghrfQf8Iud7zyZC2bzD+0PeUHtIMsb2zA+0zNzdOLN8y9f
 VC34LcQjpG4k9jgrRabAt5xJKcKPLA3rBfkZdB36NKnyj0EFndGoR5YaYsINFBrd
 Asg58Es6OQVINvLdinInpp2GAZAz30zNuF1VivjKgDIUpMw1yU7x5h+Sea3+b5n2
 hO439hlQj4Hb5yNrKeDVaOUJ8eY4yIUtGAUm1vFXODdC4y5FcH7aNf5GiY5bxC7n
 warleTm/DxCV9CI2MANOJmJgC2XgdE7/JNMNvWQnjcmOvhFywyYE65c26QMLIQSM
 k2L0b26FtlES3aCUUKaAmBvAGEZznturBg0fmpnuIULHvYWf2aLndzWDv6C5LhiQ
 mC3FAJc1rzDfQR7UsPrs
 =a2Td
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:

 - use 'pwd' instead of '/bin/pwd' for portability

 - clean up Makefiles

 - fix ld-option for clang

 - fix malloc'ed data size in Kconfig

 - fix parallel building along with coccicheck

 - fix a minor issue of package building

 - prompt to use "rpm-pkg" instead of "rpm"

 - clean up *.i and *.lst patterns by "make clean"

* tag 'kbuild-v4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: drop $(extra-y) from real-objs-y
  kbuild: clean up *.i and *.lst patterns by make clean
  kbuild: rpm: prompt to use "rpm-pkg" if "rpm" target is used
  kbuild: pkg: use --transform option to prefix paths in tar
  coccinelle: fix parallel build with CHECK=scripts/coccicheck
  kconfig/symbol.c: use correct pointer type argument for sizeof
  kbuild: Set KBUILD_CFLAGS before incl. arch Makefile
  kbuild: remove all dummy assignments to obj-
  kbuild: create built-in.o automatically if parent directory wants it
  kbuild: /bin/pwd -> pwd
2017-11-25 08:06:30 -10:00
Linus Torvalds 1d3bc6363a A few late-arriving docs updates that have no real reason to wait. There's
a new "Co-Developed-by" tag described by Greg, and a build enhancement from
 Willy to generate docs warnings during a kernel build (but only when
 additional warnings have been requested in general).
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJaFaXjAAoJEI3ONVYwIuV6AXAQAMDinEQQBxNJmO/PkQrIxT4t
 sgbLfI+Sd9zD/lEb9aC5e99XYqw+SH0H9xtEcOrhwx+fjuzkKa6NKLPWjopGzVxH
 CM+N7lCE3AFuzbBCmcQvQyEelQg+p7rsY+2MGLYxMZINnaHFgTa1lvamcE/wKu5d
 CSXs1K2TwFQEpippYlzTmiWU1Rt3gWKGwtBFgLtikSBqiS3HVr4yn7dgm1WTEpVo
 IZPQYoglHjb8vL/vnVDDsfu1PW6Q1uE1aBSgTFBgFIv3UXJBBSlfWQJ7MQsD12Ww
 ZkkAxssFm6TRa87mtgd68Du0Ebg4wZQJG9fizCSy6yIh1ExYxvG0rUmqGrZ1rRYu
 4F+hukXINn7OK5L2laKNQT8ZWCPP+RoN6YUQpz2dhXC3nULZbd5GI9y8pQTdZjmK
 p39SIovicQltlw8ap9MkzTKxm4mvLo/wjFWhQT4qH2QENKO8uSqA9BpLt5a1gJU5
 dSLKDElph5EhliQAQfN/wXdPnTzSaGovele23zTTOLu2vr2JUSnBWWwiaOwuTHRQ
 OEdzxQceoINnc/iqC1qt8F/57E8BT76YedAlmsn77umTXq3mq28wkd1RCRFcjqz5
 KeqrvC5WMSbWZXZDxow7Pr+CPONUy4WpqVbHbwcQ4V8zlFfGjtQdR6zKN88Mb364
 4oJpUwUMz36HchZpi1Tx
 =ydAe
 -----END PGP SIGNATURE-----

Merge tag 'docs-4.15-2' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "A few late-arriving docs updates that have no real reason to wait.

  There's a new "Co-Developed-by" tag described by Greg, and a build
  enhancement from Willy to generate docs warnings during a kernel build
  (but only when additional warnings have been requested in general)"

* tag 'docs-4.15-2' of git://git.lwn.net/linux:
  Add optional check for bad kernel-doc comments
  Documentation: fix profile= options in kernel-parameters.txt
  documentation/svga.txt: update outdated file
  kokr/memory-barriers.txt: Fix typo in paring example
  kokr/memory-barriers/txt: Replace uses of "transitive"
  Documentation/process: add Co-Developed-by: tag for patches with multiple authors
2017-11-23 21:01:32 -10:00
Matthew Wilcox 3a025e1d1c Add optional check for bad kernel-doc comments
Implement a '-none' output mode for kernel-doc which will only output
warning messages, and suppresses the warning message about there being
no kernel-doc in the file.

If the build has requested additional warnings, automatically check all
.c files.  This patch does not check .h files.  Enabling the warning
by default would add about 1300 warnings, so it's default off for now.
People who care can use this to check they didn't break the docs and
maybe we'll get all the warnings fixed and be able to enable this check
by default in the future.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-11-20 12:09:11 -07:00
Masahiro Yamada f7adc3124d kbuild: create built-in.o automatically if parent directory wants it
"obj-y += foo/" syntax requires Kbuild to visit the "foo" subdirectory
and link built-in.o from that directory.  This means foo/Makefile is
responsible for creating built-in.o even if there is no object to
link (in this case, built-in.o is an empty archive).

We have had several fixups like commit 4b024242e8 ("kbuild: Fix
linking error built-in.o no such file or directory"), then ended up
with a complex condition as follows:

  ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),)
  builtin-target := $(obj)/built-in.o
  endif

We still have more cases not covered by the above, so we need to add
  obj- := dummy.o
in several places just for creating empty built-in.o.

A key point is, the parent Makefile knows whether built-in.o is needed
or not.  If a subdirectory needs to create built-in.o, its parent can
tell the fact when descending.

If non-empty $(need-builtin) flag is passed from the parent, built-in.o
should be created.  $(obj-y) should be still checked to support the
single target "%/".  All of ugly tricks will go away.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
2017-11-18 11:38:58 +09:00
Linus Torvalds 09bd7c75e5 Kbuild updates for v4.15
One of the most remarkable improvements in this cycle is, Kbuild is
 now able to cache the result of shell commands.  Some variables are
 expensive to compute, for example, $(call cc-option,...) invokes the
 compiler.  It is not efficient to redo this computation every time,
 even when we are not actually building anything.  Kbuild creates a
 hidden file ".cache.mk" that contains invoked shell commands and
 their results.  The speed-up should be noticeable.
 
 Summary:
 
 - Fix arch build issues (hexagon, sh)
 
 - Clean up various Makefiles and scripts
 
 - Fix wrong usage of {CFLAGS,LDFLAGS}_MODULE in arch Makefiles
 
 - Cache variables that are expensive to compute
 
 - Improve cc-ldopton and ld-option for Clang
 
 - Optimize output directory creation
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJaDxaLAAoJED2LAQed4NsGIHQP/isMxxaIxIAWU56+ZcII74k7
 639VgrKi9n5y25d1dBRTQg+vReHE6E2JbkCqpVOu11t7m0LT7yUK8v3WwyLf1qTN
 GxnqZ/WMQU5/AYVqIWo8jN4FGHpivHJ6qbeiNJM9qN4RAkzG0sZUq746VaFZYmIR
 Lu0Gf4m4qjifkkhXsQdWT5i7yNTidPqaL6GNb+FcFkEHlVre8jma0kJlgfHxru84
 WmETpjQXvHAZ/R61vY6ekAWpqFhw3ecJY96A9npnx+SQVQdSNAdpaU0SK29jB0ON
 /SAfpHg9oa/gD0LFOKV6zkjnAkd4TEjrJEiHHhz5gjT/SbS3T1llBIGZ1oV4X7Y0
 Vlh9KWlm1FJJI4SIzc9qUaQMp6JtLfEfHKJCc45xVaN3fNrDnR8jl80x5+95ELga
 dCkZgnq5u82MtTysCbHBESwDYQaVPyIrh7In+mduglaCqhqj9KoDjoLoiGfCg7SA
 3tPflYVd629w5l5GrazJ40jWn1+ggMtgMOVooJNJ+dINCP+GxsUpH84Ww2Pdic+/
 qLdud6TeqxrZDGzWXqKNLu8alM8NGgSr101l9gIf1oqSyy63duBpMrxGDoIJS3FU
 rFDoFFUhlfkAXNbQHtVGNzKtcpCjURh992j9Fa1+NfMwSce5IHkMwTvPmNSRowi8
 0llLjXhD/bxK6FpdvlV8
 =zIdO
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:
 "One of the most remarkable improvements in this cycle is, Kbuild is
  now able to cache the result of shell commands. Some variables are
  expensive to compute, for example, $(call cc-option,...) invokes the
  compiler. It is not efficient to redo this computation every time,
  even when we are not actually building anything. Kbuild creates a
  hidden file ".cache.mk" that contains invoked shell commands and their
  results. The speed-up should be noticeable.

  Summary:

   - Fix arch build issues (hexagon, sh)

   - Clean up various Makefiles and scripts

   - Fix wrong usage of {CFLAGS,LDFLAGS}_MODULE in arch Makefiles

   - Cache variables that are expensive to compute

   - Improve cc-ldopton and ld-option for Clang

   - Optimize output directory creation"

* tag 'kbuild-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits)
  kbuild: move coccicheck help from scripts/Makefile.help to top Makefile
  sh: decompressor: add shipped files to .gitignore
  frv: .gitignore: ignore vmlinux.lds
  selinux: remove unnecessary assignment to subdir-
  kbuild: specify FORCE in Makefile.headersinst as .PHONY target
  kbuild: remove redundant mkdir from ./Kbuild
  kbuild: optimize object directory creation for incremental build
  kbuild: create object directories simpler and faster
  kbuild: filter-out PHONY targets from "targets"
  kbuild: remove redundant $(wildcard ...) for cmd_files calculation
  kbuild: create directory for make cache only when necessary
  sh: select KBUILD_DEFCONFIG depending on ARCH
  kbuild: fix linker feature test macros when cross compiling with Clang
  kbuild: shrink .cache.mk when it exceeds 1000 lines
  kbuild: do not call cc-option before KBUILD_CFLAGS initialization
  kbuild: Cache a few more calls to the compiler
  kbuild: Add a cache for generated variables
  kbuild: add forward declaration of default target to Makefile.asm-generic
  kbuild: remove KBUILD_SUBDIR_ASFLAGS and KBUILD_SUBDIR_CCFLAGS
  hexagon/kbuild: replace CFLAGS_MODULE with KBUILD_CFLAGS_MODULE
  ...
2017-11-17 17:45:29 -08:00
Masahiro Yamada c4da7ed0e7 kbuild: optimize object directory creation for incremental build
The previous commit largely optimized the object directory creation.
We can optimize it more for incremental build.

There are already *.cmd files in the output directory.  The existing
*.cmd files have been picked up by $(wildcard ...).  Obviously,
directories containing them exist too, so we can skip "mkdir -p".

With this, Kbuild runs almost zero "mkdir -p" in incremental building.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-11-16 09:07:36 +09:00
Masahiro Yamada 8a78756eb5 kbuild: create object directories simpler and faster
For the out-of-tree build, scripts/Makefile.build creates output
directories, but this operation is not efficient.

scripts/Makefile.lib calculates obj-dirs as follows:

  obj-dirs := $(dir $(multi-objs) $(obj-y))

Please notice $(sort ...) is not used here.  Usually the result is
as many "./" as objects here.

For a lot of duplicated paths, the following command is invoked.

  _dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d)))

Then, the costly shell command is run over and over again.

I see many points for optimization:

[1] Use $(sort ...) to cut down duplicated paths before passing them
    to system call
[2] Use single $(shell ...) instead of repeating it with $(foreach ...)
    This will reduce forking.
[3] We can calculate obj-dirs more simply.  Most of objects are already
    accumulated in $(targets).  So, $(dir $(targets)) is fine and more
    comprehensive.

I also removed ugly code in arch/x86/entry/vdso/Makefile.  This is now
really unnecessary.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Douglas Anderson <dianders@chromium.org>
2017-11-16 09:07:35 +09:00
Masahiro Yamada 591f668997 kbuild: filter-out PHONY targets from "targets"
The variable "targets" contains object paths for which existing .*.cmd
files should be included.

scripts/Makefile.build automatically adds $(MAKECMDGOALS) to "targets"
as follows:

  targets += $(extra-y) $(MAKECMDGOALS) $(always)

The $(MAKECMDGOALS) is a PHONY target in several places.  PHONY targets
never create .*.cmd files.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-11-16 09:07:35 +09:00
Masahiro Yamada 2982c95357 kbuild: remove redundant $(wildcard ...) for cmd_files calculation
I do not see any reason why $(wildcard ...) needs to be called twice
for computing cmd_files.  Remove the first one.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-11-16 09:07:34 +09:00
Ingo Molnar b3d9a13681 Merge branch 'linus' into x86/asm, to pick up fixes and resolve conflicts
Conflicts:
	arch/x86/kernel/cpu/Makefile

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 10:53:06 +01:00
Linus Torvalds 5cb0512c02 Kbuild: don't pass "-C" to preprocessor when processing linker scripts
For some odd historical reason, we preprocessed the linker scripts with
"-C", which keeps comments around.  That makes no sense, since the
comments are not meaningful for the build anyway.

And it actually breaks things, since linker scripts can't have C++ style
"//" comments in them, so keeping comments after preprocessing now
limits us in odd and surprising ways in our header files for no good
reason.

The -C option goes back to pre-git and pre-bitkeeper times, but seems to
have been historically used (along with "-traditional") for some
odd-ball architectures (ia64, MIPS and SH).  It probably didn't matter
back then either, but might possibly have been used to minimize the
difference between the original file and the pre-processed result.

The reason for this may be lost in time, but let's not perpetuate it
only because we can't remember why we did this crazy thing.

This was triggered by the recent addition of SPDX lines to the source
tree, where people apparently were confused about why header files
couldn't use the C++ comment format.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg KH <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-02 14:10:37 -07:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Josh Poimboeuf 11af847446 x86/unwind: Rename unwinder config options to 'CONFIG_UNWINDER_*'
Rename the unwinder config options from:

  CONFIG_ORC_UNWINDER
  CONFIG_FRAME_POINTER_UNWINDER
  CONFIG_GUESS_UNWINDER

to:

  CONFIG_UNWINDER_ORC
  CONFIG_UNWINDER_FRAME_POINTER
  CONFIG_UNWINDER_GUESS

... in order to give them a more logical config namespace.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/73972fc7e2762e91912c6b9584582703d6f1b8cc.1507924831.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-14 10:12:12 +02:00
Josh Poimboeuf da541b2002 objtool: Skip unreachable warnings for GCC 4.4 and older
The kbuild bot occasionally reports warnings like:

  drivers/scsi/pcmcia/aha152x_core.o: warning: objtool: seldo_run()+0x130: unreachable instruction

These warnings are always with GCC 4.4.  That version of GCC sometimes
places unreachable instructions after calls to noreturn functions.

The unreachable warnings aren't very important anyway.  Just ignore them
for old versions of GCC.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/bc89b807d965b98ec18a0bb94f96a594bd58f2f2.1506551639.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-28 07:23:02 +02:00
Linus Torvalds b0c79f49c3 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:

 - Introduce the ORC unwinder, which can be enabled via
   CONFIG_ORC_UNWINDER=y.

   The ORC unwinder is a lightweight, Linux kernel specific debuginfo
   implementation, which aims to be DWARF done right for unwinding.
   Objtool is used to generate the ORC unwinder tables during build, so
   the data format is flexible and kernel internal: there's no
   dependency on debuginfo created by an external toolchain.

   The ORC unwinder is almost two orders of magnitude faster than the
   (out of tree) DWARF unwinder - which is important for perf call graph
   profiling. It is also significantly simpler and is coded defensively:
   there has not been a single ORC related kernel crash so far, even
   with early versions. (knock on wood!)

   But the main advantage is that enabling the ORC unwinder allows
   CONFIG_FRAME_POINTERS to be turned off - which speeds up the kernel
   measurably:

   With frame pointers disabled, GCC does not have to add frame pointer
   instrumentation code to every function in the kernel. The kernel's
   .text size decreases by about 3.2%, resulting in better cache
   utilization and fewer instructions executed, resulting in a broad
   kernel-wide speedup. Average speedup of system calls should be
   roughly in the 1-3% range - measurements by Mel Gorman [1] have shown
   a speedup of 5-10% for some function execution intense workloads.

   The main cost of the unwinder is that the unwinder data has to be
   stored in RAM: the memory cost is 2-4MB of RAM, depending on kernel
   config - which is a modest cost on modern x86 systems.

   Given how young the ORC unwinder code is it's not enabled by default
   - but given the performance advantages the plan is to eventually make
   it the default unwinder on x86.

   See Documentation/x86/orc-unwinder.txt for more details.

 - Remove lguest support: its intended role was that of a temporary
   proof of concept for virtualization, plus its removal will enable the
   reduction (removal) of the paravirt API as well, so Rusty agreed to
   its removal. (Juergen Gross)

 - Clean up and fix FSGS related functionality (Andy Lutomirski)

 - Clean up IO access APIs (Andy Shevchenko)

 - Enhance the symbol namespace (Jiri Slaby)

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits)
  objtool: Handle GCC stack pointer adjustment bug
  x86/entry/64: Use ENTRY() instead of ALIGN+GLOBAL for stub32_clone()
  x86/fpu/math-emu: Add ENDPROC to functions
  x86/boot/64: Extract efi_pe_entry() from startup_64()
  x86/boot/32: Extract efi_pe_entry() from startup_32()
  x86/lguest: Remove lguest support
  x86/paravirt/xen: Remove xen_patch()
  objtool: Fix objtool fallthrough detection with function padding
  x86/xen/64: Fix the reported SS and CS in SYSCALL
  objtool: Track DRAP separately from callee-saved registers
  objtool: Fix validate_branch() return codes
  x86: Clarify/fix no-op barriers for text_poke_bp()
  x86/switch_to/64: Rewrite FS/GS switching yet again to fix AMD CPUs
  selftests/x86/fsgsbase: Test selectors 1, 2, and 3
  x86/fsgsbase/64: Report FSBASE and GSBASE correctly in core dumps
  x86/fsgsbase/64: Fully initialize FS and GS state in start_thread_common
  x86/asm: Fix UNWIND_HINT_REGS macro for older binutils
  x86/asm/32: Fix regs_get_register() on segment registers
  x86/xen/64: Rearrange the SYSCALL entries
  x86/asm/32: Remove a bunch of '& 0xffff' from pt_regs segment reads
  ...
2017-09-04 09:52:57 -07:00
Cao jin 312a3d0918 kbuild: trivial cleanups on the comments
This is a bunch of trivial fixes and cleanups.

Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-08-10 00:58:20 +09:00
Josh Poimboeuf ee9f8fce99 x86/unwind: Add the ORC unwinder
Add the new ORC unwinder which is enabled by CONFIG_ORC_UNWINDER=y.
It plugs into the existing x86 unwinder framework.

It relies on objtool to generate the needed .orc_unwind and
.orc_unwind_ip sections.

For more details on why ORC is used instead of DWARF, see
Documentation/x86/orc-unwinder.txt - but the short version is
that it's a simplified, fundamentally more robust debugninfo
data structure, which also allows up to two orders of magnitude
faster lookups than the DWARF unwinder - which matters to
profiling workloads like perf.

Thanks to Andy Lutomirski for the performance improvement ideas:
splitting the ORC unwind table into two parallel arrays and creating a
fast lookup table to search a subset of the unwind table.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/0a6cbfb40f8da99b7a45a1a8302dc6aef16ec812.1500938583.git.jpoimboe@redhat.com
[ Extended the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-26 13:18:20 +02:00
Josh Poimboeuf 867ac9d737 objtool: Fix gcov check for older versions of GCC
Objtool tries to silence 'unreachable instruction' warnings when it
detects gcov is enabled, because gcov produces a lot of unreachable
instructions and they don't really matter.

However, the 0-day bot is still reporting some unreachable instruction
warnings with CONFIG_GCOV_KERNEL=y on GCC 4.6.4.

As it turns out, objtool's gcov detection doesn't work with older
versions of GCC because they don't create a bunch of symbols with the
'gcov.' prefix like newer versions of GCC do.

Move the gcov check out of objtool and instead just create a new
'--no-unreachable' flag which can be passed in by the kernel Makefile
when CONFIG_GCOV_KERNEL is defined.

Also rename the 'nofp' variable to 'no_fp' for consistency with the new
'no_unreachable' variable.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 9cfffb1168 ("objtool: Skip all "unreachable instruction" warnings for gcov kernels")
Link: http://lkml.kernel.org/r/c243dc78eb2ffdabb6e927844dea39b6033cd395.1500939244.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-25 11:12:45 +02:00
Nicholas Piggin 9a6cfca4f4 kbuild: thin archives use P option to ar
The P option makes ar do full path name matching and can prevent ar
from discarding files with duplicate names in some cases of creating
thin archives from thin archives. The sh architecture in particular
loses some object files from its kernel/cpu/sh*/ directories without
this option.

This could be a bug in binutils ar, but the P option should not cause
any negative effects so it is safe to use to work around this with.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-06-30 09:03:03 +09:00
Jiri Slaby e8a3118e1f objtool: make it visible in make V=1 output
It is currently impossible to see what is going on with objtool when
building, so call echo-cmd to see the actions:
  gcc -Wp,-MD,arch/x86/entry/.entry_64.o.d  -nostdinc -isystem ...
  ./tools/objtool/objtool check "arch/x86/entry/entry_64.o";

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Michal Marek <mmarek@suse.com>
Cc: linux-kbuild@vger.kernel.org
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-05-03 13:39:37 +09:00
Vinícius Tinti 433db3e260 kbuild: Add support to generate LLVM assembly files
Add rules to kbuild in order to generate LLVM assembly files with the .ll
extension when using clang.

  # from c code
  make CC=clang kernel/pid.ll

Signed-off-by: Vinícius Tinti <viniciustinti@gmail.com>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-04-25 08:13:52 +09:00
Ard Biesheuvel 56067812d5 kbuild: modversions: add infrastructure for emitting relative CRCs
This add the kbuild infrastructure that will allow architectures to emit
vmlinux symbol CRCs as 32-bit offsets to another location in the kernel
where the actual value is stored. This works around problems with CRCs
being mistaken for relocatable symbols on kernels that self relocate at
runtime (i.e., powerpc with CONFIG_RELOCATABLE=y)

For the kbuild side of things, this comes down to the following:

 - introducing a Kconfig symbol MODULE_REL_CRCS

 - adding a -R switch to genksyms to instruct it to emit the CRC symbols
   as references into the .rodata section

 - making modpost distinguish such references from absolute CRC symbols
   by the section index (SHN_ABS)

 - making kallsyms disregard non-absolute symbols with a __crc_ prefix

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-03 08:28:25 -08:00
Linus Torvalds 41e0e24b45 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:

 - prototypes for x86 asm-exported symbols (Adam Borowski) and a warning
   about missing CRCs (Nick Piggin)

 - asm-exports fix for LTO (Nicolas Pitre)

 - thin archives improvements (Nick Piggin)

 - linker script fix for CONFIG_LD_DEAD_CODE_DATA_ELIMINATION (Nick
   Piggin)

 - genksyms support for __builtin_va_list keyword

 - misc minor fixes

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  x86/kbuild: enable modversions for symbols exported from asm
  kbuild: fix scripts/adjust_autoksyms.sh* for the no modules case
  scripts/kallsyms: remove last remnants of --page-offset option
  make use of make variable CURDIR instead of calling pwd
  kbuild: cmd_export_list: tighten the sed script
  kbuild: minor improvement for thin archives build
  kbuild: modpost warn if export version crc is missing
  kbuild: keep data tables through dead code elimination
  kbuild: improve linker compatibility with lib-ksyms.o build
  genksyms: Regenerate parser
  kbuild/genksyms: handle va_list type
  kbuild: thin archives for multi-y targets
  kbuild: kallsyms allow 3-pass generation if symbols size has changed
2016-12-17 16:24:13 -08:00
Nicolas Pitre 76bee23411 kbuild: cmd_export_list: tighten the sed script
When LTO is used, some ___ksymtab_string sections are seen by this sed
script, creating lines containing a single ) such as:

EXPORT(foo)
)
)
EXPORT(bar)

Let's make it so the + character is also required for any line to be
printed.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-12-11 11:51:43 +01:00
Nicholas Piggin 9da2f584b5 kbuild: improve linker compatibility with lib-ksyms.o build
lib-ksyms.o is created by linking an empty input file with a linker
script containing the interesting bits. Currently the empty input file
is an archive containing nothing, however this causes the gold linker
to segfault.

I have opened a bug against gold

  https://sourceware.org/bugzilla/show_bug.cgi?id=20767

However this can be worked around by assembling an empty file to link
with instead. The resulting lib-ksyms.o is slightly larger (seemingly
due to empty .text, .data, .bss setions added), but final linked
output should not be changed.

Reported-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-11-29 15:58:57 +01:00
Nicholas Piggin fe026a851b kbuild: thin archives for multi-y targets
THIN_ARCHIVES builds archives for built-in.o targets, have it build
multi-y targets as archives as well.

This saves another ~15% of the size of intermediate artifacts in the
build tree. After this patch, the linker is only used in final link,
and special cases like vdsos.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-11-29 15:53:19 +01:00
Nicholas Piggin cc6acc11ca kbuild: be more careful about matching preprocessed asm ___EXPORT_SYMBOL
The CRC code for asm exports grabs the preprocessed asm, finds the
___EXPORT_SYMBOL and turns those into EXPORT_SYMBOL in a C program
that can be preprocessed and parsed to create the CRC signatures from
the type.

The existing regex matching and replacement is too strict, and doesn't
deal well with whitespace among other things. The line
" EXPORT_SYMBOL(sym)" in a .S file would not match due to initial
whitespace, for example, which resulted in x86's ___preempt_schedule
failing to get CRCs.

Reported-by: Philip Müller <philm@manjaro.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-11-09 22:29:53 +01:00
Nicholas Piggin 4efca4ed05 kbuild: modversions for EXPORT_SYMBOL() for asm
Allow architectures to create asm/asm-prototypes.h file that
provides C prototypes for exported asm functions, which enables
proper CRC versions to be generated for them.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-11-01 16:20:17 +01:00
Nicholas Piggin 989cea5c14 kbuild: prevent lib-ksyms.o rebuilds
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reported-by: Russell King <rmk+kernel@armlinux.org.uk>
Tested-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-10-22 21:49:30 +02:00
Stephen Rothwell a5967db9af kbuild: allow architectures to use thin archives instead of ld -r
ld -r is an incremental link used to create built-in.o files in build
subdirectories. It produces relocatable object files containing all
its input files, and these are are then pulled together and relocated
in the final link. Aside from the bloat, this constrains the final
link relocations, which has bitten large powerpc builds with
unresolvable relocations in the final link.

Alan Modra has recommended the kernel use thin archives for linking.
This is an alternative and means that the linker has more information
available to it when it links the kernel.

This patch enables a config option architectures can select, which
causes all built-in.o files to be built as thin archives. built-in.o
files in subdirectories do not get symbol table or index attached,
which improves speed and size. The final link pass creates a
built-in.o archive in the root output directory which includes the
symbol table and index. The linker then uses takes this file to link.

The --whole-archive linker option is required, because the linker now
has visibility to every individual object file, and it will otherwise
just completely avoid including those without external references
(consider a file with EXPORT_SYMBOL or initcall or hardware exceptions
as its only entry points). The traditional built works "by luck" as
built-in.o files are large enough that they're going to get external
references. However this optimisation is unpredictable for the kernel
(due to above external references), ineffective at culling unused, and
costly because the .o files have to be searched for references.
Superior alternatives for link-time culling should be used instead.

Build characteristics for inclink vs thinarc, on a small powerpc64le
pseries VM with a modest .config:

                                  inclink       thinarc
sizes
vmlinux                        15 618 680    15 625 028
sum of all built-in.o          56 091 808     1 054 334
sum excluding root built-in.o                   151 430

find -name built-in.o | xargs rm ; time make vmlinux
real                              22.772s       21.143s
user                              13.280s       13.430s
sys                                4.310s        2.750s

- Final kernel pulled in only about 6K more, which shows how
  ineffective the object file culling is.
- Build performance looks improved due to less pagecache activity.
  On IO constrained systems it could be a bigger win.
- Build size saving is significant.

Side note, the toochain understands archives, so there's some tricks,
$ ar t built-in.o          # list all files you linked with
$ size built-in.o          # and their sizes
$ objdump -d built-in.o    # disassembly (unrelocated) with filenames

Implementation by sfr, minor tweaks by npiggin.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-09-09 10:31:19 +02:00
Al Viro 7f2084fa55 [kbuild] handle exports in lib-y objects reliably
Collect the symbols exported by anything that goes into lib.a and
add an empty object (lib-exports.o) with explicit undefs for each
of those to obj-y.

That allows to relax the rules regarding the use of exports in
lib-* objects - right now an object with export can be in lib-*
only if we are guaranteed that there always will be users in
built-in parts of the tree, otherwise it needs to be in obj-*.
As the result, we have an unholy mix of lib- and obj- in lib/Makefile
and (especially) in arch/*/lib/Makefile.  Moreover, a change in
generic part of the kernel can lead to mysteriously missing exports
on some configs.  With this change we don't have to worry about
that anymore.

One side effect is that built-in.o now pulls everything with exports
from the corresponding lib.a (if such exists).  That's exactly what
we want for linking vmlinux and fortunately it's almost the only thing
built-in.o is used in.  arch/ia64/hp/sim/boot/bootloader is the only
exception and it's easy to get rid of now - just turn everything in
arch/ia64/lib into lib-* and don't bother with arch/ia64/lib/built-in.o
anymore.

[AV: stylistic fix from Michal folded in]

Acked-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-08-07 23:46:30 -04:00
Emese Revfy 2440387431 Shared library support
Infrastructure for building independent shared library targets.

Based on work created by the PaX Team.

Signed-off-by: Emese Revfy <re.emese@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-06-07 22:57:10 +02:00
Masahiro Yamada e0f41e52dd kbuild: rename cmd_as_s_S to cmd_cpp_s_S
This command just preprocesses .S files into .s files, so cmd_cpp_s_S
seems more suitable.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-20 10:49:09 +02:00
Masahiro Yamada 23d4384870 kbuild: rename cmd_cc_i_c to cmd_cpp_i_c
This command just preprocesses .c files into .i files, so cmd_cpp_i_c
seems more suitable.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-20 10:48:19 +02:00
Nicolas Pitre e4aca45950 kbuild: de-duplicate fixdep usage
The generation and postprocessing of automatic dependency rules is
duplicated in rule_cc_o_c, rule_as_o_S and if_changed_dep. Since
this is not a trivial one-liner action, it is now abstracted under
cmd_and_fixdep to simplify things and make future changes in this area
easier.

In the rule_cc_o_c and rule_as_o_S cases that means the order of some
commands has been altered, namely fixdep and related file manipulations
are executed earlier, but they didn't depend on those commands that now
execute later.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
2016-03-29 16:30:56 -04:00
Nicolas Pitre 9895c03d48 kbuild: record needed exported symbols for modules
Kernel modules are partially linked object files with some undefined
symbols that are expected to be matched with EXPORT_SYMBOL() entries
from elsewhere.

Each .tmp_versions/*.mod file currently contains two line of text
separated by a newline character. The first line has the actual module
file name while the second line has a list of object files constituting
that module. Those files are parsed by modpost (scripts/mod/sumversion.c),
scripts/Makefile.modpost, scripts/Makefile.modsign, etc.  Only the
modpost utility cares about the second line while the others retrieve
only the first line.

Therefore we can add a third line to record the list of undefined symbols
aka required EXPORT_SYMBOL() entries for each module into that file
without breaking anything. Like for the second line, symbols are separated
by a blank and the list is terminated with a newline character.

To avoid needless build overhead, the undefined symbols extraction is
performed only when CONFIG_TRIM_UNUSED_KSYMS is selected.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
2016-03-29 13:30:54 -04:00
Josh Poimboeuf 3b27a0c85d objtool: Detect and warn if libelf is missing and don't break the build
With CONFIG_STACK_VALIDATION enabled, if the host system doesn't have
a development version of libelf installed, the build fails with errors
like:

  elf.h:22:18: fatal error: gelf.h: No such file or directory compilation terminated.

Instead of failing to build, instead just print a warning and disable
stack validation.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-next@vger.kernel.org
Cc: linux@roeck-us.net
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/8c27fe00face60f42e888ddb3142c97e45223165.1457026550.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-05 09:20:44 +01:00
Josh Poimboeuf b9ab5ebb14 objtool: Add CONFIG_STACK_VALIDATION option
Add a CONFIG_STACK_VALIDATION option which will run "objtool check" for
each .o file to ensure the validity of its stack metadata.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/92baab69a6bf9bc7043af0bfca9fb964a1d45546.1456719558.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-29 08:35:13 +01:00
Michal Marek cf4f21938e kbuild: Allow to specify composite modules with modname-m
This allows to write

  drm-$(CONFIG_AGP) += drm_agpsupport.o

without having to handle CONFIG_AGP=y vs. CONFIG_AGP=m. Only support
this syntax for modules, since built-in code depending on something
modular cannot work and init/Makefile actually relies on the current
semantics. There are a few drivers which adapted to the current
semantics out of necessity; these are fixed to also work when the
respective subsystem is modular.

Acked-by: Peter Chen <peter.chen@freescale.com> [chipidea]
Signed-off-by: Michal Marek <mmarek@suse.com>
2015-11-25 11:23:25 +01:00
Heiko Carstens c0a80c0c27 ftrace: allow architectures to specify ftrace compile options
If the kernel is compiled with function tracer support the -pg compile option
is passed to gcc to generate extra code into the prologue of each function.

This patch replaces the "open-coded" -pg compile flag with a CC_FLAGS_FTRACE
makefile variable which architectures can override if a different option
should be used for code generation.

Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-01-29 09:19:19 +01:00
Masahiro Yamada a4954fd772 kbuild: remove obj-n and lib-n handling
Kconfig never defines CONFIG_* as 'n'.
Now obj-n is only used in firmware/Makefile and it can be
replaced with obj-.  No makefile uses lib-n.

Let's rip off obj-n and lib-n.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Peter Foley <pefoley2@pefoley.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-10-02 13:55:02 +02:00
Masahiro Yamada c8589d1e9e kbuild: handle multi-objs dependency appropriately
The comment in scripts/Makefile.build says as follows:

  We would rather have a list of rules like
        foo.o: $(foo-objs)
  but that's not so easy, so we rather make all composite objects depend
  on the set of all their parts

This commit makes it possible!

For example, assume a Makefile like this

  obj-m = foo.o bar.o
  foo-objs := foo1.o foo2.o
  bar-objs := bar1.o bar2.o

Without this patch, foo.o depends on all of
foo1.o foo2.o bar1.o bar2.o.
It looks funny that foo.o is regenerated when bar1.c is updated.

Now we can handle the dependency of foo.o and bar.o separately.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-08-19 10:26:19 +02:00
Masahiro Yamada 38385f8f01 kbuild: trivial - remove trailing spaces
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-04-30 17:34:32 +02:00
Masahiro Yamada a86fe35373 kbuild: move extra gcc checks to scripts/Makefile.extrawarn
W=... provides extra gcc checks.

Having such code in scripts/Makefile.build results in the same flags
being added to KBUILD_CFLAGS multiple times becuase
scripts/Makefile.build is invoked every time Kbuild descends into
the subdirectories.

Since the top Makefile is already too cluttered, this commit moves
all of extra gcc check stuff to a new file scripts/Makefile.extrawarn,
which is included from the top Makefile.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
CC: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-04-16 23:28:41 +02:00
Jan-Simon Möller 3d3d6b8474 kbuild: LLVMLinux: Adapt warnings for compilation with clang
When compiling kernel with clang, disable warnings which are too noisy, and
add the clang flag catch-undefined-behavior.

Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Mark Charlebois <mcharleb@gmail.com>
Cc: PaX Team <pageexec@freemail.hu>
2014-04-09 13:44:34 -07:00
Andi Kleen 1e64ff42ea Kbuild, lto: Disable LTO for asm-offsets.c
The asm-offset.c technique to fish data out of the assembler file
does not work with LTO. Just disable for the asm-offset.c build.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1391846481-31491-11-git-send-email-ak@linux.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-13 20:25:03 -08:00
James Hogan d70f82acf3 genksyms: pass symbol-prefix instead of arch
Pass symbol-prefix to genksyms instead of arch, so that the decision
what symbol prefix to use is kept in one place.

Basically genksyms used to take a -a $ARCH argument and it used that to
determine whether to add an underscore symbol prefix. It's now changed
to take a -s $SYMBOL_PREFIX argument so that the caller decides whether
a symbol prefix is required. The build system then uses
CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX to determine whether to pass the
argument.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-03-20 11:27:27 +10:30
David Howells 4520c6a49a X.509: Add simple ASN.1 grammar compiler
Add a simple ASN.1 grammar compiler.  This produces a bytecode output that can
be fed to a decoder to inform the decoder how to interpret the ASN.1 stream it
is trying to parse.

Action functions can be specified in the grammar by interpolating:

	({ foo })

after a type, for example:

	SubjectPublicKeyInfo ::= SEQUENCE {
		algorithm		AlgorithmIdentifier,
		subjectPublicKey	BIT STRING ({ do_key_data })
		}

The decoder is expected to call these after matching this type and parsing the
contents if it is a constructed type.

The grammar compiler does not currently support the SET type (though it does
support SET OF) as I can't see a good way of tracking which members have been
encountered yet without using up extra stack space.

Currently, the grammar compiler will fail if more than 256 bytes of bytecode
would be produced or more than 256 actions have been specified as it uses
8-bit jump values and action indices to keep space usage down.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-10-08 13:50:19 +10:30
Kirill A. Shutemov f858ee8b8c kbuild: disable -Wmissing-field-initializers for W=1
-Wmissing-field-initializers is too noisy to be useful on W=1. Let's
move it to W=2.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-01-26 11:07:26 +01:00
Arnaud Lacombe 49c57d254e scripts/Makefile.build: do not reference EXTRA_CFLAGS as CFLAGS replacement
Usage of these flags has been deprecated for nearly 4 years by:

    commit f77bf01425
    Author: Sam Ravnborg <sam@neptun.(none)>
    Date:   Mon Oct 15 22:25:06 2007 +0200

        kbuild: introduce ccflags-y, asflags-y and ldflags-y

Moreover, these flags (at least EXTRA_CFLAGS) have been documented for
command line use. By default, gmake(1) do not override command line
setting, so this is likely to result in build failure or unexpected
behavior.

Do not advertise for its usage.

Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-08-31 16:41:39 +02:00
Linus Torvalds 2bb732cdb4 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  kbuild: make KBUILD_NOCMDDEP=1 handle empty built-in.o
  scripts/kallsyms.c: fix potential segfault
  scripts/gen_initramfs_list.sh: Convert to a /bin/sh script
  kbuild: Fix GNU make v3.80 compatibility
  kbuild: Fix passing -Wno-* options to gcc 4.4+
  kbuild: move scripts/basic/docproc.c to scripts/docproc.c
  kbuild: Fix Makefile.asm-generic for um
  kbuild: Allow to combine multiple W= levels
  kbuild: Disable -Wunused-but-set-variable for gcc 4.6.0
  Fix handling of backlash character in LINUX_COMPILE_BY name
  kbuild: asm-generic support
  kbuild: implement several W= levels
  kbuild: Fix build with binutils <= 2.19
  initramfs: Use KBUILD_BUILD_TIMESTAMP for generated entries
  kbuild: Allow to override LINUX_COMPILE_BY and LINUX_COMPILE_HOST macros
  kbuild: Drop unused LINUX_COMPILE_TIME and LINUX_COMPILE_DOMAIN macros
  kbuild: Use the deterministic mode of ar
  kbuild: Call gzip with -n
  kbuild: move KALLSYMS_EXTRA_PASS from Kconfig to Makefile
  Kconfig: improve KALLSYMS_ALL documentation

Fix up trivial conflict in Makefile
2011-05-24 13:31:37 -07:00
Michal Marek d6971822c2 ftrace/kbuild: Add recordmcount files to force full build
Modifications to recordmcount must be performed on all object
files to stay consistent with what the kernel code may expect.
Add the recordmcount files to the main dependencies to make sure
any change to them causes a full recompile.

Signed-off-by: Michal Marek <mmarek@suse.cz>
Link: http://lkml.kernel.org/r/20110517133646.GP13293@sepie.suse.cz
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-05-19 07:58:28 -04:00
Steven Rostedt 85356f8022 kbuild/recordmcount: Add RECORDMCOUNT_WARN to warn about mcount callers
When mcount is called in a section that ftrace will not modify it into
a nop, we want to warn about this. But not warn about this always. Now
if the user builds the kernel with the option RECORDMCOUNT_WARN=1 then
the build will warn about mcount callers that are ignored and will just
waste execution time.

Acked-by: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Link: http://lkml.kernel.org/r/20110421023738.714956282@goodmis.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-05-16 14:45:03 -04:00
Michal Marek a6de553da0 kbuild: Allow to combine multiple W= levels
Add support for make W=12, make W=123 and so on, to enable warnings from
multiple W= levels. Normally, make W=<level> does not include warnings
from the previous level.

Signed-off-by: Michal Marek <mmarek@suse.cz>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-By: Valdis Kletnieks <valdis.kletnieks@vt.edu>
2011-05-02 17:37:10 +02:00
Dave Jones af0e5d565d kbuild: Disable -Wunused-but-set-variable for gcc 4.6.0
Disable the new -Wunused-but-set-variable that was added in gcc 4.6.0
It produces more false positives than useful warnings.

This can still be enabled using W=1

Signed-off-by: Dave Jones <davej@redhat.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Tested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-04-29 16:58:14 +02:00
Sam Ravnborg 28bc20dcca kbuild: implement several W= levels
Building a kernel with "make W=1" produces far too much noise to be
useful.

Divide the warning options in three groups:

    W=1 - warnings that may be relevant and does not occur too often
    W=2 - warnings that occur quite often but may still be relevant
    W=3 - the more obscure warnings, can most likely be ignored

When building the whole kernel, those levels produce:

W=1 - 4859 warnings
W=2 - 1394 warnings
W=3 - 86666 warnings

respectively. Warnings have been counted with Geert's script at

http://www.kernel.org/pub/linux/kernel/people/geert/linux-log/linux-log-summary.pl

Many warnings occur from .h files so fixing one file may have a nice
effect on the total number of warnings.

With these changes I am actually tempted to try W=1 now and then.
Previously there was just too much noise.

Borislav:

- make the W= levels exclusive
- move very noisy and making little sense for the kernel warnings to W=3
- drop -Woverlength-strings due to useless warning message
- copy explanatory text for the different warning levels to 'make help'
- recount warnings per level

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Borislav Petkov <bp@alien8.de>
Cc: Dave Jones <davej@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-04-28 17:59:07 +02:00
Michal Marek 40df759e2b kbuild: Fix build with binutils <= 2.19
The D option of ar is only available in newer versions.

Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-04-20 15:39:22 +02:00
Michal Marek 09ff9fecc0 kbuild: Use the deterministic mode of ar
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-04-18 14:24:45 +02:00
Borislav Petkov 4a5838ad9d kbuild: Add extra gcc checks
Add a 'W=1' Makefile switch which adds additional checking per build
object.

The idea behind this option is targeted at developers who, in the
process of writing their code, want to do the occasional

make W=1 [target.o]

and let gcc do more extensive code checking for them. Then, they
could eyeball the output for valid gcc warnings about various
bugs/discrepancies which are not reported during the normal build
process.

For more background information and a use case, read through this
thread: http://marc.info/?l=kernel-janitors&m=129802065918147&w=2

Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-03-09 15:35:35 +01:00
Wu Zhangjin 45677454dd ftrace: Speed up recordmcount
cmd_record_mcount is used to locate the _mcount symbols in the object
files, only the files compiled with -pg has the _mcount symbol, so, it
is only needed for such files, but the current cmd_record_mcount is used
for all of the object files, so, we need to fix it and speed it up.

Since -pg may be removed by the method used in kernel/trace/Makefile:

ORIG_CFLAGS := $(KBUILD_CFLAGS)
KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))

Or may be removed by the method used in arch/x86/kernel/Makefile:

CFLAGS_REMOVE_file.o = -pg

So, we must check the last variable stores the compiling flags, that is
c_flags(Please refer to cmd_cc_o_c and rule_cc_o_c defined in
scripts/Makefile.build) and since the CFLAGS_REMOVE_file.o is already
filtered in _c_flags(Please refer to scripts/Makefile.lib) and _c_flags
has less symbols, therefore, we only need to check _c_flags.

---------------
Changes from v1:

  o Don't touch Makefile for CONFIG_FTRACE_MCOUNT_RECORD is enough
  o Use _c_flags intead of KBUILD_CFLAGS to cover CONFIG_REMOVE_file.o = -pg
  (feedback from Steven Rostedt <rostedt@goodmis.org>)

Acked-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
LKML-Reference: <3dc8cddf022eb7024f9f2cf857529a15bee8999a.1288196498.git.wuzhangjin@gmail.com>

[ changed if [ .. == .. ] to if [ .. = .. ] to handle dash environments ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-11-18 17:16:05 -05:00
Linus Torvalds b5153163ed Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (278 commits)
  arm: remove machine_desc.io_pg_offst and .phys_io
  arm: use addruart macro to establish debug mappings
  arm: return both physical and virtual addresses from addruart
  arm/debug: consolidate addruart macros for CONFIG_DEBUG_ICEDCC
  ARM: make struct machine_desc definition coherent with its comment
  eukrea_mbimxsd-baseboard: Pass the correct GPIO to gpio_free
  cpuimx27: fix compile when ULPI is selected
  mach-pcm037_eet: fix compile errors
  Fixing ethernet driver compilation error for i.MX31 ADS board
  cpuimx51: update board support
  mx5: add cpuimx51sd module and its baseboard
  iomux-mx51: fix GPIO_1_xx 's IOMUX configuration
  imx-esdhc: update devices registration
  mx51: add resources for SD/MMC on i.MX51
  iomux-mx51: fix SD1 and SD2's iomux configuration
  clock-mx51: rename CLOCK1 to CLOCK_CCGR for better readability
  clock-mx51: factorize clk_set_parent and clk_get_rate
  eukrea_mbimxsd: add support for DVI displays
  cpuimx25 & cpuimx35: fix OTG port registration in host mode
  i.MX31 and i.MX35 : fix errate TLSbo65953 and ENGcm09472
  ...
2010-10-21 16:42:32 -07:00
Steven Rostedt d7b4d6de57 ftrace: Remove recursion between recordmcount and scripts/mod/empty
When DYNAMIC_FTRACE is enabled and we use the C version of recordmcount,
all objects are run through the recordmcount program to create a
separate section that stores all the callers of mcount.

The build process has a special file: scripts/mod/empty.o. This is
built from empty.c which is literally an empty file (except for a
single comment). This file is used to find information about the target
elf format, like endianness and word size.

The problem comes up when we need to build recordmcount. The
build process requires that empty.o is built first. The build rules
for empty.o will try to execute recordmcount on the empty.o file.
We get an error that recordmcount does not exist.

To avoid this recursion, the build file will skip running recordmcount
if the file that it is building is script/mod/empty.o.

[ extra comment Suggested-by: Sam Ravnborg <sam@ravnborg.org> ]

Reported-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Ingo Molnar <mingo@elte.hu>
Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-10-18 17:08:10 -04:00
Steven Rostedt 85caa993d7 ftrace: Use objtree for C version of recordmcount
The C version of recordmcount is compiled to a binary, which will
end up located in the objtree. If the kernel is built with O=path,
the srctree will not include the binary recordmcount caller.

Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-10-15 12:09:25 -04:00
Steven Rostedt 72441cb1fd ftrace/x86: Add support for C version of recordmcount
This patch adds the support for the C version of recordmcount and
compile times show ~ 12% improvement.

After verifying this works, other archs can add:

 HAVE_C_MCOUNT_RECORD

in its Kconfig and it will use the C version of recordmcount
instead of the perl version.

Cc: <linux-arch@vger.kernel.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Cc: John Reiser <jreiser@bitwagon.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-10-14 16:52:41 -04:00
Rabin Vincent f9810a8253 ARM: 6317/1: ftrace: pass KBUILD_CFLAGS to record_mcount.pl
On ARM, we have two ABIs, and the ABI used is controlled via a config
option.  Object files built with one ABI can't be merged with object
files built with the other ABI.  So, record_mcount.pl needs to use the
same compiler flags as the kernel when generating the object file with
the mcount locations.  Ensure this by passing CFLAGS to the script.

Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-02 15:26:39 +01:00
Sam Ravnborg 80c00ba942 kbuild: allow assignment to {A,C}FLAGS_KERNEL on the command line
It is now possible to assign options to AS and CC
on the command line - which is only used for built-in code.

{A,C}FLAGS_KERNEL was used both in the top-level Makefile
in the arch makefiles, thus users had no way to specify
additional options to AS, CC without overriding
the original value.

Introduce a new set of variables KBUILD_{A,C}FLAGS_KERNEL
that is used by arch specific files and free up
{A,C}FLAGS_KERNEL so they can be assigned on
the command line.

All arch Makefiles that used the old variables has been updated.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-08-03 14:09:45 +02:00
Sam Ravnborg 6588169d51 kbuild: allow assignment to {A,C,LD}FLAGS_MODULE on the command line
It is now possible to assign options to AS, CC and LD
on the command line - which is only used when building modules.

{A,C,LD}FLAGS_MODULE was all used both in the top-level Makefile
in the arch makefiles, thus users had no way to specify
additional options to AS, CC, LD when building modules
without overriding the original value.

Introduce a new set of variables KBUILD_{A,C,LD}FLAGS_MODULE
that is used by arch specific files and free up
{A,C,LD}FLAGS_MODULE so they can be assigned on
the command line.

All arch Makefiles that used the old variables has been updated.

Note: Previously we had a MODFLAGS variable for both
AS and CC. But in favour of consistency this was dropped.
So in some cases arch Makefile has one assignmnet replaced by
two assignmnets.

Note2: MODFLAGS was not documented and is dropped
without any notice. I do not expect much/any breakage
from this.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Acked-by: Mike Frysinger <vapier@gentoo.org> [blackfin]
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> [avr32]
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-08-03 14:09:45 +02:00
Don Zickus e26d6b834c Makefile.build: make KBUILD_SYMTYPES work again
commit 37a8d9f67f tried to combine some
duplicate code and accidentally broke how KBUILD_SYMTYPES worked

This fixes the code to match the original intention by the author who
originally added the code I believe.

The fixes include:
- removing extra whitespaces in the if-statements
- moving the if-statement from around the -r to the -T
- adding a second arg to cmd_gensymtypes to simplify the options passed
  to genksyms.

Tested by instrumenting genksyms and seeing what options were passed in
during a make, KBUILD_SYMTYPES make, and when a foo.symref was created.

Everything compiled and looked ok.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-06-04 12:46:48 +02:00
Jiafu He 4b024242e8 kbuild: Fix linking error built-in.o no such file or directory
This patch fixes the link error "built-in.o: no such file or directory".
The problem happens if "dirx/Makefile" contains only "obj-m += diry/
dirz/" and the empty "dirx/built-in.o" is missing. Adding $(subdir-m)
into check for builtin-target fixes this error.

Signed-off-by: Jiafu He <jay@goldhive.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-02-02 14:33:54 +01:00
Wu Zhangjin e6299d2677 MIPS: Tracing: Add an endian argument to scripts/recordmcount.pl
MIPS and some other architectures need this argument to handle
big/little endian respectively.

Signed-off-by: Wu Zhangjin <wuzj@lemote.com>
Cc: Nicholas Mc Guire <der.herr@hofr.at>
Cc: zhangfx@lemote.com
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/674/
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-12-17 01:57:22 +00:00
Tim Abbott 42f29a2520 kbuild: Don't define ALIGN and ENTRY when preprocessing linker scripts.
Adding a reference to <linux/linkage.h> to x86's <asm/cache.h> causes
the x86 linker script to have syntax errors, because the ALIGN and
ENTRY keywords get redefined to the assembly implementations of those.
One could fix this by adjusting the include structure, but I think any
solution based on that approach would be fragile.

Currently, it is impossible when writing a header to do something
different for assembly files and linker scripts, even though there are
clearly cases where one wants them to define macros differently for
the two (ENTRY being an excellent example).
So I think the right solution here is to introduce a new preprocessor
definition, called LINKER_SCRIPT that is set along with __ASSEMBLY__
for linker scripts, and to use that to not define ALIGN and ENTRY in
linker scripts.
I suspect we'll find other uses for this mechanism in
the future.

Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-09-21 06:27:08 +02:00
Sam Ravnborg 51b563fc93 arm, cris, mips, sparc, powerpc, um, xtensa: fix build with bash 4.0
Albin Tonnerre <albin.tonnerre@free-electrons.com> reported:

    Bash 4 filters out variables which contain a dot in them.
    This happends to be the case of CPPFLAGS_vmlinux.lds.
    This is rather unfortunate, as it now causes
    build failures when using SHELL=/bin/bash to compile,
    or when bash happens to be used by make (eg when it's /bin/sh)

Remove the common definition of CPPFLAGS_vmlinux.lds by
pushing relevant stuff to either Makefile.build or the
arch specific kernel/Makefile where we build the linker script.

This is also nice cleanup as we move the information out where
it is used.

Notes for the different architectures touched:

arm - we use an already exported symbol
cris - we use a config symbol aleady available
       [Not build tested]
mips - the jiffies complexity has moved to vmlinux.lds.S where we need it.
       Added a few variables to CPPFLAGS - they are only used by
       the linker script.
       [Not build tested]
powerpc - removed assignment that is not needed
          [not build tested]
sparc - simplified it using $(BITS)
um - introduced a few new exported variables to deal with this
xtensa - added options to CPP invocation
         [not build tested]

Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-09-20 12:28:22 +02:00
Andi Kleen 66a570623b kbuild: fail build if recordmcount.pl fails
When this script fails the build should fail too. Otherwise there
are mysterious build failures later.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-09-20 12:27:44 +02:00
Andi Kleen c3c63b6bec kbuild: echo the record_mcount command
I had some problems with record_mcount in the Makefile and it was hard
to track down. Echo it by default to make it easier to diagnose.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-09-20 12:27:44 +02:00
Sam Ravnborg 720097d895 kbuild: introduce subdir-ccflags-y
Following patch introduce support for setting options
to gcc that has effect for current directory and all
subdirectories.

The typical use case are an architecture or a subsystem that
decide to cover all files with -Werror.
Today alpha, mips and sparc uses -Werror in almost all their
Makefile- with subdir-ccflag-y it is now simpler to do so
as only the top-level directories needs to be covered.

Likewise if we decide to cover a full subsystem such
as net/ with -Werror this is done by adding a single
line to net/Makefile.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
2009-04-19 11:12:12 +02:00
Ingo Molnar dc573f9b20 Merge branches 'tracing/ftrace', 'tracing/kmemtrace' and 'linus' into tracing/core 2009-02-03 06:25:38 +01:00
Sam Ravnborg 2ea038917b Revert "kbuild: strip generated symbols from *.ko"
This reverts commit ad7a953c52.

And commit: ("allow stripping of generated symbols under CONFIG_KALLSYMS_ALL")
            9bb482476c

These stripping patches has caused a set of issues:

1) People have reported compatibility issues with binutils due to
   lack of support for `--strip-unneeded-symbols' with objcopy 2.15.92.0.2
   Reported by: Wenji
2) ccache and distcc no longer works as expeced
   Reported by: Ted, Roland, + others
3) The installed modules increased a lot in size
   Reported by: Ted, Davej + others

Reported-by: Wenji Huang <wenji.huang@oracle.com>
Reported-by: "Theodore Ts'o" <tytso@mit.edu>
Reported-by: Dave Jones <davej@redhat.com>
Reported-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-01-14 21:38:20 +01:00
Shaohua Li 18c167fd6d ftrace, ia64: make recordmcount distinct module compile
In IA64, module build and kernel build use different option.
Make recordmcount.pl differentiate the two cases.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-14 12:11:08 +01:00
Linus Torvalds 96faec945f Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next: (25 commits)
  allow stripping of generated symbols under CONFIG_KALLSYMS_ALL
  kbuild: strip generated symbols from *.ko
  kbuild: simplify use of genksyms
  kernel-doc: check for extra kernel-doc notations
  kbuild: add headerdep used to detect inclusion cycles in header files
  kbuild: fix string equality testing in tags.sh
  kbuild: fix make tags/cscope
  kbuild: fix make incompatibility
  kbuild: remove TAR_IGNORE
  setlocalversion: add git-svn support
  setlocalversion: print correct subversion revision
  scripts: improve the decodecode script
  scripts/package: allow custom options to rpm
  genksyms: allow to ignore symbol checksum changes
  genksyms: track symbol checksum changes
  tags and cscope support really belongs in a shell script
  kconfig: fix options to check-lxdialog.sh
  kbuild: gen_init_cpio expands shell variables in file names
  remove bashisms from scripts/extract-ikconfig
  kbuild: teach mkmakfile to be silent
  ...
2008-12-28 15:13:48 -08:00
Jan Beulich ad7a953c52 kbuild: strip generated symbols from *.ko
This patch changes the way __crc_ symbols are being resolved from
using ld to do so to using the assembler, thus allowing these symbols
to be marked local (the linker creates then as global ones) and hence
allow stripping (for modules) or ignoring (for vmlinux) them. While at
this, also strip other generated symbols during module installation.

One potentially debatable point is the handling of the flags passeed
to gcc when translating the intermediate assembly file into an object:
passing $(c_flags) unchanged doesn't work as gcc passes --gdwarf2 to
gas whenever is sees any -g* option, even for -g0, and despite the
fact that the compiler would have already produced all necessary debug
info in the C->assembly translation phase. I took the approach of just
filtering out all -g* options, but an alternative to such negative
filtering might be to have a positive filter which might, in the ideal
case allow just all the -Wa,* options to pass through.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-12-19 22:41:15 +01:00
Sam Ravnborg 37a8d9f67f kbuild: simplify use of genksyms
Avoid duplicating long list of options in two places

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-12-19 22:00:58 +01:00
Andreas Gruenbacher 64e6c1e123 genksyms: track symbol checksum changes
Sometimes it is preferable to avoid changes of exported symbol checksums
(to avoid breaking externally provided modules).  When a checksum change
occurs, it can be hard to figure out what caused this change: underlying
types may have changed, or additional type information may simply have
become available at the point where a symbol is exported.

Add a new --reference option to genksyms which allows it to report why
checksums change, based on the type information dumps it creates with the
--dump-types flag.  Genksyms will read in such a dump from a previous run,
and report which symbols have changed (and why).

The behavior can be controlled for an entire build as follows: If
KBUILD_SYMTYPES is set, genksyms uses --dump-types to produce *.symtypes
dump files.  If any *.symref files exist, those will be used as the
reference to check against.  If KBUILD_PRESERVE is set, checksum changes
will fail the build.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-12-03 22:33:11 +01:00
Steven Rostedt b3acf29afd ftrace, kbuild: condense recordmcount.pl parameter code
Impact: cleanup

Sam Ravnborg pointed out that I could condense the code for the parameters of
recordmcount.pl by using an $(if ...) condition.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-31 00:38:34 +01:00
Steven Rostedt dce9d18add ftrace: handle generic arch calls
The recordmcount script requires that the actual arch is passed in.
This works well when ARCH=i386 or ARCH=x86_64 but does not handle the
case of ARCH=x86.

This patch adds a parameter to the function to pass in the number of
bits of the architecture. So that it can determine if x86 should be
run for x86_64 or i386 archs.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-23 15:58:19 +02:00
Andrew Morton b3a3204174 kbuild: ftrace: don't assume that scripts/recordmcount.pl is executable
CHK     include/linux/version.h
  CHK     include/linux/utsrelease.h
  CC      scripts/mod/empty.o
/bin/sh: /usr/src/25/scripts/recordmcount.pl: Permission denied

We shouldn't assume that files have their `x' bits set.  There are various
ways in which file permissions get lost, including use of patch(1).

It might not be correct to assume that perl lives in $PATH?

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-14 10:36:16 +02:00
Jeremy Fitzhardinge 6a4917e3ae ftrace: fix build problem with CONFIG_FTRACE
I'm seeing when I use separate src/build dirs:

make[3]: *** [arch/x86/kernel/time_32.o] Error 1
/bin/sh: scripts/recordmcount.pl: No such file or directory
make[3]: *** [arch/x86/kernel/irq_32.o] Error 1
/bin/sh: scripts/recordmcount.pl: No such file or directory
make[3]: *** [arch/x86/kernel/ldt.o] Error 1
/bin/sh: scripts/recordmcount.pl: No such file or directory
make[3]: *** [arch/x86/kernel/i8259.o] Error 1
/bin/sh: scripts/recordmcount.pl: No such file or directory

This fixes it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-14 10:35:53 +02:00
Steven Rostedt 8da3821ba5 ftrace: create __mcount_loc section
This patch creates a section in the kernel called "__mcount_loc".
This will hold a list of pointers to the mcount relocation for
each call site of mcount.

For example:

objdump -dr init/main.o
[...]
Disassembly of section .text:

0000000000000000 <do_one_initcall>:
   0:   55                      push   %rbp
[...]
000000000000017b <init_post>:
 17b:   55                      push   %rbp
 17c:   48 89 e5                mov    %rsp,%rbp
 17f:   53                      push   %rbx
 180:   48 83 ec 08             sub    $0x8,%rsp
 184:   e8 00 00 00 00          callq  189 <init_post+0xe>
                        185: R_X86_64_PC32      mcount+0xfffffffffffffffc
[...]

We will add a section to point to each function call.

   .section __mcount_loc,"a",@progbits
[...]
   .quad .text + 0x185
[...]

The offset to of the mcount call site in init_post is an offset from
the start of the section, and not the start of the function init_post.
The mcount relocation is at the call site 0x185 from the start of the
.text section.

  .text + 0x185  == init_post + 0xa

We need a way to add this __mcount_loc section in a way that we do not
lose the relocations after final link.  The .text section here will
be attached to all other .text sections after final link and the
offsets will be meaningless.  We need to keep track of where these
.text sections are.

To do this, we use the start of the first function in the section.
do_one_initcall.  We can make a tmp.s file with this function as a reference
to the start of the .text section.

   .section __mcount_loc,"a",@progbits
[...]
   .quad do_one_initcall + 0x185
[...]

Then we can compile the tmp.s into a tmp.o

  gcc -c tmp.s -o tmp.o

And link it into back into main.o.

  ld -r main.o tmp.o -o tmp_main.o
  mv tmp_main.o main.o

But we have a problem.  What happens if the first function in a section
is not exported, and is a static function. The linker will not let
the tmp.o use it.  This case exists in main.o as well.

Disassembly of section .init.text:

0000000000000000 <set_reset_devices>:
   0:   55                      push   %rbp
   1:   48 89 e5                mov    %rsp,%rbp
   4:   e8 00 00 00 00          callq  9 <set_reset_devices+0x9>
                        5: R_X86_64_PC32        mcount+0xfffffffffffffffc

The first function in .init.text is a static function.

00000000000000a8 t __setup_set_reset_devices
000000000000105f t __setup_str_set_reset_devices
0000000000000000 t set_reset_devices

The lowercase 't' means that set_reset_devices is local and is not exported.
If we simply try to link the tmp.o with the set_reset_devices we end
up with two symbols: one local and one global.

 .section __mcount_loc,"a",@progbits
 .quad set_reset_devices + 0x10

00000000000000a8 t __setup_set_reset_devices
000000000000105f t __setup_str_set_reset_devices
0000000000000000 t set_reset_devices
                 U set_reset_devices

We still have an undefined reference to set_reset_devices, and if we try
to compile the kernel, we will end up with an undefined reference to
set_reset_devices, or even worst, it could be exported someplace else,
and then we will have a reference to the wrong location.

To handle this case, we make an intermediate step using objcopy.
We convert set_reset_devices into a global exported symbol before linking
it with tmp.o and set it back afterwards.

00000000000000a8 t __setup_set_reset_devices
000000000000105f t __setup_str_set_reset_devices
0000000000000000 T set_reset_devices

00000000000000a8 t __setup_set_reset_devices
000000000000105f t __setup_str_set_reset_devices
0000000000000000 T set_reset_devices

00000000000000a8 t __setup_set_reset_devices
000000000000105f t __setup_str_set_reset_devices
0000000000000000 t set_reset_devices

Now we have a section in main.o called __mcount_loc that we can place
somewhere in the kernel using vmlinux.ld.S and access it to convert
all these locations that call mcount into nops before starting SMP
and thus, eliminating the need to do this with kstop_machine.

Note, A well documented perl script (scripts/recordmcount.pl) is used
to do all this in one location.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-14 10:34:40 +02:00
Robert P. J. Day 3156fd0529 kbuild: fix some minor typoes
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-04-25 20:18:48 +02:00
Sam Ravnborg 91341d4b2c kbuild: introduce new option to enhance section mismatch analysis
Setting the option DEBUG_SECTION_MISMATCH will
report additional section mismatch'es but this
should in the end makes it possible to get rid of
all of them.

See help text in lib/Kconfig.debug for details.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-28 23:21:18 +01:00
Tejun Heo 551559e13a kbuild: implement modules.order
When multiple built-in modules (especially drivers) provide the same
capability, they're prioritized by link order specified by the order
listed in Makefile.  This implicit ordering is lost for loadable
modules.

When driver modules are loaded by udev, what comes first in
modules.alias file is selected.  However, the order in this file is
indeterministic (depends on filesystem listing order of installed
modules).  This causes confusion.

The solution is two-parted.  This patch updates kbuild such that it
generates and installs modules.order which contains the name of
modules ordered according to Makefile.  The second part is update to
depmod such that it generates output files according to this file.

Note that both obj-y and obj-m subdirs can contain modules and
ordering information between those two are lost from beginning.
Currently obj-y subdirs are put before obj-m subdirs.

Sam Ravnborg cleaned up Makefile modifications and suggested using awk
to remove duplicate lines from modules.order instead of using separate
C program.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Bill Nottingham <notting@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jon Masters <jonathan@jonmasters.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-28 23:14:35 +01:00
Sam Ravnborg f77bf01425 kbuild: introduce ccflags-y, asflags-y and ldflags-y
Introduce ccflags-y, asflags-y and ldflags-y so we soon can
deprecate use of EXTRA_CFLAGS, EXTRA_AFLAGS and EXTRA_LDFLAGS.
This patch does not touch any in-tree users - thats next round.
Lets get this committed first and then fix the users of the
soon to be deprecated variants next.

The rationale behind this change is to introduce support for
makefile fragments like:

ccflags-$(CONFIG_WHATEVER_DEBUG) := -DDEBUG

As a replacement for the uglier:
ifeq ($(CONFIG_WHATEVER_DEBUG),y)
        EXTRA_CFLAGS := -DDEBUG
endif

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-10-15 22:25:06 +02:00
Sam Ravnborg 0c53c8e6eb kbuild: check for wrong use of CFLAGS
External modules have in a few cases modifed gcc option
by modifying CFLAGS. This has never been documented and
was a bad practice.
With the check to use KBUILD_CFLAGS it will no longer work
so we better error out and tell what was wrong as a service
to the external module users.

This check can be overruled if
KBUILD_NOPEDANTIC is set to something.
Addid this possibility may allow older external
module to build without any code modifications but potentially
only loosing some un-important gcc options.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-10-14 22:26:53 +02:00
Sam Ravnborg 836caba77c kbuild: kill backward compatibility checks
These checks has been present for several kernel releases (> 5).
So lets just get rid of them.
With this we no longer check for use of:
EXTRA_TARGETS, O_TARGET, L_TARGET, list-multi, export-objs

There were three remaining in-tree users of O_TARGET in some
unmaintained sh64 code - mail sent to the maintainer + list.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-10-12 21:20:32 +02:00
Sam Ravnborg 5e54d5e5fb kbuild: kill EXTRA_ARFLAGS
EXTRA_ARFLAGS have never been used so no need to carry
around on this.
A google search did not reveal any external module
using this either.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-10-12 21:20:32 +02:00
Roland McGrath 114f515777 kbuild: use LDFLAGS_MODULE only for .ko links
Sam Ravnborg pointed out that Documentation/kbuild/makefiles.txt already
says this is what it's for.  This patch makes the reality live up to the
documentation.  This fixes the problem of LDFLAGS_BUILD_ID getting into too
many places.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-07-25 21:18:19 +02:00
Sam Ravnborg d72e5edbf4 kbuild: avoid environment to set variables used by kbuild
A few of the variables used by kbuild has fixed naming.
Make sure we do not pick up random values from the environment.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-07-16 21:15:49 +02:00
Sam Ravnborg 767e581d75 kbuild: enable use of code from a different dir
To introduce support for source in one directory but output files
in another directory during a non O= build prefix all paths
with $(src) repsectively $(obj).

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-06 09:23:45 +02:00
Sam Ravnborg 48f1f0589d kbuild: consistently decide when to rebuild a target
Consistently decide when to rebuild a target across all of
if_changed, if_changed_dep, if_changed_rule.
PHONY targets are now treated alike (ignored) for all targets

While add it make Kbuild.include almost readable by factoring out a few
bits to some common variables and reuse this in Makefile.build.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-09-25 09:00:00 +02:00
Sam Ravnborg 5e8d780d74 kbuild: fix ia64 breakage after introducing make -rR
kbuild used $¤(*F to get filename of target without extension.
This was used in several places all over kbuild, but introducing
make -rR broke his for all cases where we specified full path to
target/prerequsite. It is assumed that make -rR disables old style
suffix-rules which is why is suddenly failed.

ia64 was impacted by this change because several div* routines in
arch/ia64/lib are build using explicit paths and then kbuild failed.

Thanks to David Mosberger-Tang <David.Mosberger@acm.org> for an explanation
what was the root-cause and for testing on ia64.

This patch also fixes two uses of $(*F) in arch/um

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-07-01 09:58:02 +02:00
Linus Torvalds d38b69689c Revert "kbuild: fix make -rR breakage"
This reverts commit e5c44fd88c.

Thanks to Daniel Ritz and Michal Piotrowski for noticing the problem.

Daniel says:

  "[The] reason is a recent change that made modules always shows as
   module.mod.  it breaks modprobe and probably many scripts..besides
   lsmod looking horrible

   stuff like this in modprobe.conf:
        install pcmcia_core /sbin/modprobe --ignore-install pcmcia_core; /sbin/modprobe pcmcia
   makes modprobe fork/exec endlessly calling itself...until oom
   interrupts it"

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 16:59:26 -07:00
Andreas Gruenbacher 15fde67518 kbuild: support for %.symtypes files
Here is a patch that adds a new -T option to genksyms for generating dumps of
the type definition that makes up the symbol version hashes. This allows to
trace modversion changes back to what caused them. The dump format is the
name of the type defined, followed by its definition (which is almost C):

  s#list_head struct list_head { s#list_head * next , * prev ; }

The s#, u#, e#, and t# prefixes stand for struct, union, enum, and typedef.
The exported symbols do not define types, and thus do not have an x# prefix:

  nfs4_acl_get_whotype int nfs4_acl_get_whotype ( char * , t#u32 )

The symbol type defintion of a single file can be generated with:

  make fs/jbd/journal.symtypes

If KBUILD_SYMTYPES is defined, all the *.symtypes of all object files that
export symbols are generated.

The single *.symtypes files can be combined into a single file after a kernel
build with a script like the following:

for f in $(find -name '*.symtypes' | sort); do
    f=${f#./}
    echo "/* ${f%.symtypes}.o */"
    cat $f
    echo
done \
| sed -e '\:UNKNOWN:d' \
      -e 's:[,;] }:}:g' \
      -e 's:\([[({]\) :\1:g' \
      -e 's: \([])},;]\):\1:g' \
      -e 's: $::' \
      $f \
| awk '
/^.#/   { if (defined[$1] == $0) {
            print $1
            next
          }
          defined[$1] = $0
        }
        { print }
'

When the kernel ABI changes, diffing individual *.symtype files, or the
combined files, against each other will show which symbol changes caused the
ABI changes. This can save a tremendous amount of time.

Dump the types that make up modversions

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-06-24 23:42:46 +02:00
Sam Ravnborg e5c44fd88c kbuild: fix make -rR breakage
make failed to supply the filename when using make -rR and using $(*F)
to get target filename without extension.
This bug was not reproduceable in small scale but using:
$(basename $(notdir $@)) fixes it with same functionality.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-06-24 23:13:59 +02:00
Roman Zippel c955ccafc3 kconfig: fix .config dependencies
This fixes one of the worst kbuild warts left - the broken dependencies used
to check and regenerate the .config file.  This was done via an indirect
dependency and the .config itself had an empty command, which can cause make
not to reread the changed .config file.

Instead of this we generate now a new file include/config/auto.conf from
.config, which is used for kbuild and has the proper dependencies.  It's also
the main make target now for all files generated during this step (and thus
replaces include/linux/autoconf.h).

This also means we can now relax the syntax requirements for the .config file
and we don't have to rewrite it all the time, i.e.  silentoldconfig only
writes .config now when it's necessary to keep it in sync with the Kconfig
files and even this can be suppressed by setting the environment variable
KCONFIG_NOSILENTUPDATE, so the update can (and must) be done manually.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-06-09 07:31:30 +02:00
Chuck Ebbert 7d1859835c kbuild: add -fverbose-asm to i386 Makefile
Add -fverbose-asm to i386 Makefile rule for building .s files.  This makes
the assembler output much more readable for humans.

Suggested by Der Herr Hofrat <der.herr@hofr.at>

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-03-12 23:35:16 +01:00
Sam Ravnborg c79c7b0923 kbuild: fix genksyms build error
genksyms needs to know when a symbol must have a "_" prefex as is
true for a few architectures.
Pass $(ARCH) as commandline argument and hardcode what architectures that
needs this info.
Previous attemt to take it from elfconfig.h was br0ken since elfconfig.h
is a generated file.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-03-12 22:54:34 +01:00
Paul Smith 4f1933620f kbuild: change kbuild to not rely on incorrect GNU make behavior
The kbuild system takes advantage of an incorrect behavior in GNU make.
Once this behavior is fixed, all files in the kernel rebuild every time,
even if nothing has changed.  This patch ensures kbuild works with both
the incorrect and correct behaviors of GNU make.

For more details on the incorrect behavior, see:

http://lists.gnu.org/archive/html/bug-make/2006-03/msg00003.html

Changes in this patch:
  - Keep all targets that are to be marked .PHONY in a variable, PHONY.
  - Add .PHONY: $(PHONY) to mark them properly.
  - Remove any $(PHONY) files from the $? list when determining whether
    targets are up-to-date or not.

Signed-off-by: Paul Smith <psmith@gnu.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-03-06 00:09:51 +01:00
Jan Beulich 6176aa9ae4 kbuild: consolidate command line escaping
While the recent change to also escape # symbols when storing C-file
compilation command lines was helpful, it should be in effect for all
command lines, as much as the dollar escaping should be in effect for
C-source compilation commands. Additionally, for better readability and
maintenance, consolidating all the escaping (single quotes, dollars,
and now sharps) was also desirable.

Signed-Off-By: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-02-19 09:51:21 +01:00
Sam Ravnborg 20a468b513 kbuild: make cc-version available in kbuild files
Move $(CC) support functions to Kbuild.include so they are available
in the kbuild files.
In addition the following was done:
	o as-option documented in Documentation/kbuild/makefiles.txt
	o Moved documentation to new section to match
	  new scope of functions
	o added cc-ifversion used to conditionally select a text string
	  dependent on actual $(CC) version
	o documented cc-ifversion
	o change so Kbuild.include is read before the kbuild file

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-02-19 09:51:20 +01:00
Sam Ravnborg d51bfb7852 kbuild: introduce escsq to escapre single quotes
This makes things a little bit more reader friendly and gvim is less
confused.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-01-06 22:35:59 +01:00
Sam Ravnborg db8c1a7b2c kbuild: fix building external modules
kbuild failed to locate Makefile for external modules.
This brought to my attention how the variables for directories
have different values in different usage scenarios.

Different kbuild usage scenarios:
make       - plain make in same directory where kernel source lives
make O=    - kbuild is told to store output files in another directory
make M=    - building an external module
make O= M= - building an external module with kernel output seperate from src

Value assigned to the different variables:

           |$(src)          |$(obj) |$(srctree)        |$(objtree)
make       |reldir to k src |as src |abs path to k src |abs path to k src
make O=    |reldir to k src |as src |abs path to k src |abs path to output dir
make M=    |abs path to src |as src |abs path to k src |abs path to k src
make O= M= |abs path to src |as src |abs path to k src |abs path to k output

path to kbuild file:

make       | $(srctree)/$(src), $(src)
make O=    | $(srctree)/$(src)
make M=    | $(src)
make O= M= | $(src)

From the table above it can be seen that the only good way to find the
home directory of the kbuild file is to locate the one of the two variants
that is an absolute path. If $(src) is an absolute path (starts with /)
then use it, otherwise prefix $(src) with $(srctree).

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-07-27 22:11:01 +02:00
Sam Ravnborg 2a69147034 kbuild: fix make O=...
kbuild failed to locate Kbuild.include.
Teach kbuild how to find Kbuild files when using make O=...

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
---
2005-07-25 20:26:04 +00:00
Sam Ravnborg 8ec4b4ff1c kbuild: introduce Kbuild.include
Kbuild.include is a placeholder for definitions originally present in
both the top-level Makefile and scripts/Makefile.build.
There were a slight difference in the filechk definition, so the most videly
used version was kept and usr/Makefile was adopted for this syntax.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
---
2005-07-25 20:10:36 +00:00
Sam Ravnborg cfca82f217 kbuild: Fix build as root then user
From: Matthew Wilcox <matthew@wil.cx>
I inadvertently built a tree as root and then rebuilt it as a user.  I
got a lot of prompts ...

mv: overwrite `drivers/char/drm/drm_auth.o', overriding mode 0644?

Using mv -f fixes that.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-07-14 20:12:40 +00:00
Jan Beulich 8476994af7 [PATCH] apply quotation handling to Makefile.build
Adding quotation handling to rule_cc_o_c in scripts/Makefile.build as used
elsewhere.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:28 -07:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00