I received a build failure for a new patch I'm working on the nds32
architecture, and when I went to test it, I couldn't get to my build error,
because it failed to build with a bunch of:
Error: invalid operands (*UND* and *UND* sections) for `^'
issues with various files. Those files were temporary asm files that looked
like: kernel/.tmp_mc_fork.s
I decided to look deeper, and found that the "mc" portion of that name
stood for "mcount", and was created by the recordmcount.pl script. One that
I wrote over a decade ago. Once I knew the source of the problem, I was
able to investigate it further.
The way the recordmcount.pl script works (BTW, there's a C version that
simply modifies the ELF object) is by doing an "objdump" on the object
file. Looks for all the calls to "mcount", and creates an offset of those
locations from some global variable it can use (usually a global function
name, found with <.*>:). Creates a asm file that is a table of references
to these locations, using the found variable/function. Compiles it and
links it back into the original object file. This asm file is called
".tmp_mc_<object_base_name>.s".
The problem here is that the objdump produced by the nds32 object file,
contains things that look like:
0000159a <.L3^B1>:
159a: c6 00 beqz38 $r6, 159a <.L3^B1>
159a: R_NDS32_9_PCREL_RELA .text+0x159e
159c: 84 d2 movi55 $r6, #-14
159e: 80 06 mov55 $r0, $r6
15a0: ec 3c addi10.sp #0x3c
Where ".L3^B1 is somehow selected as the "global" variable to index off of.
Then the assembly file that holds the mcount locations looks like this:
.section __mcount_loc,"a",@progbits
.align 2
.long .L3^B1 + -5522
.long .L3^B1 + -5384
.long .L3^B1 + -5270
.long .L3^B1 + -5098
.long .L3^B1 + -4970
.long .L3^B1 + -4758
.long .L3^B1 + -4122
[...]
And when it is compiled back to an object to link to the original object,
the compile fails on the "^" symbol.
Simple solution for now, is to have the perl script ignore using function
symbols that have an "^" in the name.
Link: https://lkml.kernel.org/r/20211014143507.4ad2c0f7@gandalf.local.home
Cc: stable@vger.kernel.org
Acked-by: Greentime Hu <green.hu@gmail.com>
Fixes: fbf58a52ac ("nds32/ftrace: Add RECORD_MCOUNT support")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When building ARCH=riscv allmodconfig with llvm-objcopy, the objcopy
version warning from this script appears:
WARNING: could not find objcopy version or version is less than 2.17.
Local function references are disabled.
The check_objcopy() function in scripts/recordmcount.pl is set up to
parse GNU objcopy's version string, not llvm-objcopy's, which triggers
the warning.
Commit 799c434154 ("kbuild: thin archives make default for all archs")
made binutils 2.20 mandatory and commit ba64beb174 ("kbuild: check the
minimum assembler version in Kconfig") enforces this at configuration
time so just remove check_objcopy() and $can_use_local instead, assuming
--globalize-symbol is always available.
llvm-objcopy has supported --globalize-symbol since LLVM 7.0.0 in 2018
and the minimum version for building the kernel with LLVM is 10.0.1 so
there is no issue introduced:
Link: ee5be798da
Link: https://lkml.kernel.org/r/20210802210307.3202472-1-nathan@kernel.org
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
- Convert sh and sparc to use generic shell scripts to generate the
syscall headers
- refactor .gitignore files
- Update kernel/config_data.gz only when the content of the .config is
really changed, which avoids the unneeded re-link of vmlinux
- move "remove stale files" workarounds to scripts/remove-stale-files
- suppress unused-but-set-variable warnings by default for Clang as well
- fix locale setting LANG=C to LC_ALL=C
- improve 'make distclean'
- always keep intermediate objects from scripts/link-vmlinux.sh
- move IF_ENABLED out of <linux/kconfig.h> to make it self-contained
- misc cleanups
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Merge tag 'kbuild-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild updates from Masahiro Yamada:
- Convert sh and sparc to use generic shell scripts to generate the
syscall headers
- refactor .gitignore files
- Update kernel/config_data.gz only when the content of the .config
is really changed, which avoids the unneeded re-link of vmlinux
- move "remove stale files" workarounds to scripts/remove-stale-files
- suppress unused-but-set-variable warnings by default for Clang
as well
- fix locale setting LANG=C to LC_ALL=C
- improve 'make distclean'
- always keep intermediate objects from scripts/link-vmlinux.sh
- move IF_ENABLED out of <linux/kconfig.h> to make it self-contained
- misc cleanups
* tag 'kbuild-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits)
linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h>
kbuild: Don't remove link-vmlinux temporary files on exit/signal
kbuild: remove the unneeded comments for external module builds
kbuild: make distclean remove tag files in sub-directories
kbuild: make distclean work against $(objtree) instead of $(srctree)
kbuild: refactor modname-multi by using suffix-search
kbuild: refactor fdtoverlay rule
kbuild: parameterize the .o part of suffix-search
arch: use cross_compiling to check whether it is a cross build or not
kbuild: remove ARCH=sh64 support from top Makefile
.gitignore: prefix local generated files with a slash
kbuild: replace LANG=C with LC_ALL=C
Makefile: Move -Wno-unused-but-set-variable out of GCC only block
kbuild: add a script to remove stale generated files
kbuild: update config_data.gz only when the content of .config is changed
.gitignore: ignore only top-level modules.builtin
.gitignore: move tags and TAGS close to other tag files
kernel/.gitgnore: remove stale timeconst.h and hz.bc
usr/include: refactor .gitignore
genksyms: fix stale comment
...
* Support for the memtest= kernel command-line argument.
* Support for building the kernel with FORTIFY_SOURCE.
* Support for generic clockevent broadcasts.
* Support for the buildtar build target.
* Some build system cleanups to pass more LLVM-friendly arguments.
* Support for kprobes.
* A rearranged kernel memory map, the first part of supporting sv48
systems.
* Improvements to kexec, along with support for kdump and crash kernels.
* An alternatives-based errata framework, along with support for
handling a pair of errata that manifest on some SiFive designs
(including the HiFive Unmatched).
* Support for XIP.
* A device tree for the Microchip PolarFire ICICLE SoC and associated
dev board.
Along with a bunch of cleanups. There are already a handful of fixes
on the list so there will likely be a part 2.
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Merge tag 'riscv-for-linus-5.13-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt:
- Support for the memtest= kernel command-line argument.
- Support for building the kernel with FORTIFY_SOURCE.
- Support for generic clockevent broadcasts.
- Support for the buildtar build target.
- Some build system cleanups to pass more LLVM-friendly arguments.
- Support for kprobes.
- A rearranged kernel memory map, the first part of supporting sv48
systems.
- Improvements to kexec, along with support for kdump and crash
kernels.
- An alternatives-based errata framework, along with support for
handling a pair of errata that manifest on some SiFive designs
(including the HiFive Unmatched).
- Support for XIP.
- A device tree for the Microchip PolarFire ICICLE SoC and associated
dev board.
... along with a bunch of cleanups. There are already a handful of fixes
on the list so there will likely be a part 2.
* tag 'riscv-for-linus-5.13-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (45 commits)
RISC-V: Always define XIP_FIXUP
riscv: Remove 32b kernel mapping from page table dump
riscv: Fix 32b kernel build with CONFIG_DEBUG_VIRTUAL=y
RISC-V: Fix error code returned by riscv_hartid_to_cpuid()
RISC-V: Enable Microchip PolarFire ICICLE SoC
RISC-V: Initial DTS for Microchip ICICLE board
dt-bindings: riscv: microchip: Add YAML documentation for the PolarFire SoC
RISC-V: Add Microchip PolarFire SoC kconfig option
RISC-V: enable XIP
RISC-V: Add crash kernel support
RISC-V: Add kdump support
RISC-V: Improve init_resources()
RISC-V: Add kexec support
RISC-V: Add EM_RISCV to kexec UAPI header
riscv: vdso: fix and clean-up Makefile
riscv/mm: Use BUG_ON instead of if condition followed by BUG.
riscv/kprobe: fix kernel panic when invoking sys_read traced by kprobe
riscv: Set ARCH_HAS_STRICT_MODULE_RWX if MMU
riscv: module: Create module allocations without exec permissions
riscv: bpf: Avoid breaking W^X
...
LANG gives a weak default to each LC_* in case it is not explicitly
defined. LC_ALL, if set, overrides all other LC_* variables.
LANG < LC_CTYPE, LC_COLLATE, LC_MONETARY, LC_NUMERIC, ... < LC_ALL
This is why documentation such as [1] suggests to set LC_ALL in build
scripts to get the deterministic result.
LANG=C is not strong enough to override LC_* that may be set by end
users.
[1]: https://reproducible-builds.org/docs/locales/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Matthias Maennich <maennich@google.com>
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net> (mptcp)
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Prior to clang 13.0.0, the RISC-V name for the mcount symbol was
"mcount", which differs from the GCC version of "_mcount", which results
in the following errors:
riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_level':
main.c:(.text+0xe): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_start':
main.c:(.text+0x4e): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `__traceiter_initcall_finish':
main.c:(.text+0x92): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `.LBB32_28':
main.c:(.text+0x30c): undefined reference to `mcount'
riscv64-linux-gnu-ld: init/main.o: in function `free_initmem':
main.c:(.text+0x54c): undefined reference to `mcount'
This has been corrected in https://reviews.llvm.org/D98881 but the
minimum supported clang version is 10.0.1. To avoid build errors and to
gain a working function tracer, adjust the name of the mcount symbol for
older versions of clang in mount.S and recordmcount.pl.
Link: https://github.com/ClangBuiltLinux/linux/issues/1331
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
By default, emacs indents Perl files with 4 spaces, but will use tabs
where 8 spaces are used. Add a vim command of softtabstop=4, to make vim
behave the same. This should remove the issue of developers using vim
having causing different indentation.
"John (Warthog9) Hawley" <warthog9@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Emacs by default will have perl files have 4 space indents, where 8 spaces
are represented with a single tab. There are some places in
recordmcount.pl that has 8 spaces where a tab should be used. Replace them
to make the file consistent.
No functional changes.
Cc: "John (Warthog9) Hawley" <warthog9@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The kernel test robot reported the following issue:
CC [M] drivers/soc/litex/litex_soc_ctrl.o
sh4-linux-objcopy: Unable to change endianness of input file(s)
sh4-linux-ld: cannot find drivers/soc/litex/.tmp_gl_litex_soc_ctrl.o: No such file or directory
sh4-linux-objcopy: 'drivers/soc/litex/.tmp_mx_litex_soc_ctrl.o': No such file
The problem is that the format of input file is elf32-shbig-linux, but
sh4-linux-objcopy wants to output a file which format is elf32-sh-linux:
$ sh4-linux-objdump -d drivers/soc/litex/litex_soc_ctrl.o | grep format
drivers/soc/litex/litex_soc_ctrl.o: file format elf32-shbig-linux
Link: https://lkml.kernel.org/r/20210210150435.2171567-1-rong.a.chen@intel.com
Link: https://lore.kernel.org/linux-mm/202101261118.GbbYSlHu-lkp@intel.com
Signed-off-by: Rong Chen <rong.a.chen@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Cc: Rich Felker <dalias@libc.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently the kernel minimal compiler requirement is gcc 4.9 or
clang 10.0.1.
* gcc -mhotpatch option is supported since 4.8.
* A combination of -pg -mrecord-mcount -mnop-mcount -mfentry flags is
supported since gcc 9 and since clang 10.
Drop support for old -pg function prologues. Which leaves binary
compatible -mhotpatch / -mnop-mcount -mfentry prologues in a form:
brcl 0,0
Which are also do not require initial nop optimization / conversion and
presence of _mcount symbol.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Based on 1 normalized pattern(s):
licensed under the terms of the gnu gpl license version 2
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 62 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.929121379@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- allow users to invoke 'make' out of the source tree
- refactor scripts/mkmakefile
- deprecate KBUILD_SRC, which was used to track the source tree
location for O= build.
- fix recordmcount.pl in case objdump output is localized
- turn unresolved symbols in external modules to errors from warnings
by default; pass KBUILD_MODPOST_WARN=1 to get them back to warnings
- generate modules.builtin.modinfo to collect .modinfo data from
built-in modules
- misc Makefile cleanups
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Merge tag 'kbuild-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- allow users to invoke 'make' out of the source tree
- refactor scripts/mkmakefile
- deprecate KBUILD_SRC, which was used to track the source tree
location for O= build.
- fix recordmcount.pl in case objdump output is localized
- turn unresolved symbols in external modules to errors from warnings
by default; pass KBUILD_MODPOST_WARN=1 to get them back to warnings
- generate modules.builtin.modinfo to collect .modinfo data from
built-in modules
- misc Makefile cleanups
* tag 'kbuild-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (21 commits)
.gitignore: add more all*.config patterns
moduleparam: Save information about built-in modules in separate file
Remove MODULE_ALIAS() calls that take undefined macro
.gitignore: add leading and trailing slashes to generated directories
scripts/tags.sh: fix direct execution of scripts/tags.sh
scripts: override locale from environment when running recordmcount.pl
samples: kobject: allow CONFIG_SAMPLE_KOBJECT to become y
samples: seccomp: turn CONFIG_SAMPLE_SECCOMP into a bool option
kbuild: move Documentation to vmlinux-alldirs
kbuild: move samples/ to KBUILD_VMLINUX_OBJS
modpost: make KBUILD_MODPOST_WARN also configurable for external modules
kbuild: check arch/$(SRCARCH)/include/generated before out-of-tree build
kbuild: remove unneeded dependency for include/config/kernel.release
memory: squash drivers/memory/Makefile.asm-offsets
kbuild: use $(srctree) instead of KBUILD_SRC to check out-of-tree build
kbuild: mkmakefile: generate a simple wrapper of top Makefile
kbuild: mkmakefile: do not check the generated Makefile marker
kbuild: allow Kbuild to start from any directory
kbuild: pass $(MAKECMDGOALS) to sub-make as is
kbuild: fix warning "overriding recipe for target 'Makefile'"
...
recordmcount.pl uses a set of regular expressions to parse the output of
objdump(1). However, if objdump(1) output is localized, it may not match
the regular expressions, thereby preventing recordmcount.pl from parsing
object files correctly.
In order to allow recordmcount.pl to function correctly regardless of the
current locale settings, set LANG=C when running objdump(1). LC_ALL is
already unset in the top-level Makefile, so it is not necessary to also
override that environment variable.
Signed-off-by: Daniel Dadap <ddadap@nvidia.com>
Reviewed-by: Robert Morell <rmorell@nvidia.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Support dynamic ftrace including dynamic graph tracer. Gcc-csky with -pg
will produce call site in every function prologue and we can use these
call site to hook trace function.
gcc with -pg origin call site:
push lr
jbsr _mcount
nop32
nop32
If the (callee - caller)'s offset is in range of bsr instruction, we'll
modify code with:
push lr
bsr _mcount
nop32
nop32
Else if the (callee - caller)'s offset is out of bsr instrunction, we'll
modify code with:
push lr
movih r26, ...
ori r26, ...
jsr r26
(r26 is reserved for jsr link reg in csky abiv2 spec.)
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
When building with -ffunction-sections, the compiler will place each
function into its own ELF section, prefixed with ".text". For example,
a simple test module with functions test_module_do_work() and
test_module_wq_func():
% objdump --section-headers test_module.o | awk '/\.text/{print $2}'
.text
.text.test_module_do_work
.text.test_module_wq_func
.init.text
.exit.text
Adjust the recordmcount scripts to look for ".text" as a section name
prefix. This will ensure that those functions will be included in the
__mcount_loc relocations:
% objdump --reloc --section __mcount_loc test_module.o
OFFSET TYPE VALUE
0000000000000000 R_X86_64_64 .text.test_module_do_work
0000000000000008 R_X86_64_64 .text.test_module_wq_func
0000000000000010 R_X86_64_64 .init.text
Link: http://lkml.kernel.org/r/1542745158-25392-2-git-send-email-joe.lawrence@redhat.com
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Recognize NDS32 object files in recordmcount.pl.
Signed-off-by: Zong Li <zong@andestech.com>
Acked-by: Greentime Hu <greentime@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
The powerpc toolchain can compile combinations of 32/64 bit and
big/little endian, so it's convenient to consider, e.g.,
`CC -m64 -mbig-endian`
To be the C compiler for the purpose of invoking it to build target
artifacts. So overriding the CC variable to include these flags works
for this purpose.
Unfortunately that is not compatible with the way the proposed new
Kconfig macro language will work.
After previous patches in this series, these flags can be carefully
passed in using flags instead.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This tag contains the new features we'd like to incorporate into the
RISC-V port for 4.17. We might have a bit more stuff land later in the
merge window, but I wanted to get this out earlier just so everyone can
see where we currently stand.
A short summary of the changes is:
* We've added support for dynamic ftrace on RISC-V targets.
* There have been a handful of cleanups to our atomic and locking
routines. They now more closely match the released RISC-V memory
model draft.
* Our module loading support has been cleaned up and is now enabled by
default, despite some limitations still existing.
* A patch to define COMMANDLINE_FORCE instead of COMMANDLINE_OVERRIDE so
the generic device tree code picks up handling all our command line
stuff.
There's more information in the merge commits for each patch set.
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Merge tag 'riscv-for-linus-4.17-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux
Pull RISC-V updates from Palmer Dabbelt:
"This contains the new features we'd like to incorporate into the
RISC-V port for 4.17. We might have a bit more stuff land later in the
merge window, but I wanted to get this out earlier just so everyone
can see where we currently stand.
A short summary of the changes is:
- We've added support for dynamic ftrace on RISC-V targets.
- There have been a handful of cleanups to our atomic and locking
routines. They now more closely match the released RISC-V memory
model draft.
- Our module loading support has been cleaned up and is now enabled
by default, despite some limitations still existing.
- A patch to define COMMANDLINE_FORCE instead of COMMANDLINE_OVERRIDE
so the generic device tree code picks up handling all our command
line stuff.
There's more information in the merge commits for each patch set"
* tag 'riscv-for-linus-4.17-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: (21 commits)
RISC-V: Rename CONFIG_CMDLINE_OVERRIDE to CONFIG_CMDLINE_FORCE
RISC-V: Add definition of relocation types
RISC-V: Enable module support in defconfig
RISC-V: Support SUB32 relocation type in kernel module
RISC-V: Support ADD32 relocation type in kernel module
RISC-V: Support ALIGN relocation type in kernel module
RISC-V: Support RVC_BRANCH/JUMP relocation type in kernel modulewq
RISC-V: Support HI20/LO12_I/LO12_S relocation type in kernel module
RISC-V: Support CALL relocation type in kernel module
RISC-V: Support GOT_HI20/CALL_PLT relocation type in kernel module
RISC-V: Add section of GOT.PLT for kernel module
RISC-V: Add sections of PLT and GOT for kernel module
riscv/atomic: Strengthen implementations with fences
riscv/spinlock: Strengthen implementations with fences
riscv/barrier: Define __smp_{store_release,load_acquire}
riscv/ftrace: Add HAVE_FUNCTION_GRAPH_RET_ADDR_PTR support
riscv/ftrace: Add DYNAMIC_FTRACE_WITH_REGS support
riscv/ftrace: Add ARCH_SUPPORTS_FTRACE_OPS support
riscv/ftrace: Add dynamic function graph tracer support
riscv/ftrace: Add dynamic function tracer support
...
Now recordmcount.pl recognizes RISC-V object files. For the mechanism to
work, we have to disable the linker relaxation.
Cc: Greentime Hu <greentime@andestech.com>
Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
These two architectures are getting removed, so we no longer
need the special cases.
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The default NetBSD package manager is pkgsrc and it installs Perl
along other third party programs under custom and configurable prefix.
The default prefix for binary prebuilt packages is /usr/pkg, and the
Perl executable lands in /usr/pkg/bin/perl.
This change switches "/usr/bin/perl" to "/usr/bin/env perl" as it's
the most portable solution that should work for almost everybody.
Perl's executable is detected automatically.
This change switches -w option passed to the executable with more
modern "use warnings;" approach. There is no functional change to the
default behavior.
While there, drop "require 5" from scripts/namespace.pl (Perl from 1994?).
Signed-off-by: Kamil Rytarowski <n54@gmx.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Adding a hook into free_reserve_area() that informs ftrace that boot up init
text is being free, lets ftrace safely remove those init functions from its
records, which keeps ftrace from trying to modify text that no longer
exists.
Note, this still does not allow for tracing .init text of modules, as
modules require different work for freeing its init code.
Link: http://lkml.kernel.org/r/1488502497.7212.24.camel@linux.intel.com
Cc: linux-mm@kvack.org
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Requested-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fix typos and add the following to the scripts/spelling.txt:
swith||switch
swithable||switchable
swithed||switched
swithing||switching
While we are here, fix the "update" to "updates" in the touched hunk in
drivers/net/wireless/marvell/mwifiex/wmm.c.
Link: http://lkml.kernel.org/r/1481573103-11329-2-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When doing an nmi backtrace of many cores, most of which are idle, the
output is a little overwhelming and very uninformative. Suppress
messages for cpus that are idling when they are interrupted and just
emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN".
We do this by grouping all the cpuidle code together into a new
.cpuidle.text section, and then checking the address of the interrupted
PC to see if it lies within that section.
This commit suitably tags x86 and tile idle routines, and only adds in
the minimal framework for other architectures.
Link: http://lkml.kernel.org/r/1472487169-14923-5-git-send-email-cmetcalf@mellanox.com
Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Daniel Thompson <daniel.thompson@linaro.org> [arm]
Tested-by: Petr Mladek <pmladek@suse.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
be7635e728 ("arch, ftrace: for KASAN put hard/soft IRQ entries into
separate sections") added .softirqentry.text section, but it was not added
to recordmcount. So functions in the section are untracable. Add the
section to scripts/recordmcount.c and scripts/recordmcount.pl.
Fixes: be7635e728 ("arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections")
Link: http://lkml.kernel.org/r/1474902626-73468-1-git-send-email-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Steve Rostedt <rostedt@goodmis.org>
Cc: <stable@vger.kernel.org> [4.6+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a text section starts out with a data blob before the first
function start label, disassembly parsing doing in recordmcount.pl
gets confused on powerpc, leading to creation of corrupted module
objects.
This was not a problem so far since the compiler would never create
such text sections. However, this has changed with a recent change
in GCC 6 to support distances of > 2GB between a function and its
assoicated TOC in the ELFv2 ABI, exposing this problem.
There is already code in recordmcount.pl to handle such data blobs
on the sparc64 platform. This patch uses the same method to handle
those on powerpc as well.
Cc: stable@vger.kernel.org
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pull s390 updates from Martin Schwidefsky:
- The remaining patches for the z13 machine support: kernel build
option for z13, the cache synonym avoidance, SMT support,
compare-and-delay for spinloops and the CES5S crypto adapater.
- The ftrace support for function tracing with the gcc hotpatch option.
This touches common code Makefiles, Steven is ok with the changes.
- The hypfs file system gets an extension to access diagnose 0x0c data
in user space for performance analysis for Linux running under z/VM.
- The iucv hvc console gets wildcard spport for the user id filtering.
- The cacheinfo code is converted to use the generic infrastructure.
- Cleanup and bug fixes.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (42 commits)
s390/process: free vx save area when releasing tasks
s390/hypfs: Eliminate hypfs interval
s390/hypfs: Add diagnose 0c support
s390/cacheinfo: don't use smp_processor_id() in preemptible context
s390/zcrypt: fixed domain scanning problem (again)
s390/smp: increase maximum value of NR_CPUS to 512
s390/jump label: use different nop instruction
s390/jump label: add sanity checks
s390/mm: correct missing space when reporting user process faults
s390/dasd: cleanup profiling
s390/dasd: add locking for global_profile access
s390/ftrace: hotpatch support for function tracing
ftrace: let notrace function attribute disable hotpatching if necessary
ftrace: allow architectures to specify ftrace compile options
s390: reintroduce diag 44 calls for cpu_relax()
s390/zcrypt: Add support for new crypto express (CEX5S) adapter.
s390/zcrypt: Number of supported ap domains is not retrievable.
s390/spinlock: add compare-and-delay to lock wait loops
s390/tape: remove redundant if statement
s390/hvc_iucv: add simple wildcard matches to the iucv allow filter
...
Make use of gcc's hotpatch support to generate better code for ftrace
function tracing.
The generated code now contains only a six byte nop in each function
prologue instead of a 24 byte code block which will be runtime patched to
support function tracing.
With the new code generation the runtime overhead for supporting function
tracing is close to zero, while the original code did show a significant
performance impact.
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>
If the function tracer is enabled, allow to set kprobes on the first
instruction of a function (which is the function trace caller):
If no kprobe is set handling of enabling and disabling function tracing
of a function simply patches the first instruction. Either it is a nop
(right now it's an unconditional branch, which skips the mcount block),
or it's a branch to the ftrace_caller() function.
If a kprobe is being placed on a function tracer calling instruction
we encode if we actually have a nop or branch in the remaining bytes
after the breakpoint instruction (illegal opcode).
This is possible, since the size of the instruction used for the nop
and branch is six bytes, while the size of the breakpoint is only
two bytes.
Therefore the first two bytes contain the illegal opcode and the last
four bytes contain either "0" for nop or "1" for branch. The kprobes
code will then execute/simulate the correct instruction.
Instruction patching for kprobes and function tracer is always done
with stop_machine(). Therefore we don't have any races where an
instruction is patched concurrently on a different cpu.
Besides that also the program check handler which executes the function
trace caller instruction won't be executed concurrently to any
stop_machine() execution.
This allows to keep full fault based kprobes handling which generates
correct pt_regs contents automatically.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
31 bit and 64 bit diverge more and more and it is rather painful
to keep both parts running.
To make things simpler just remove the 31 bit support which nobody
uses anyway.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Recordmcount utility under scripts is run, after compiling each object,
to find out all the locations of calling _mcount() and put them into
specific seciton named __mcount_loc.
Then linker collects all such information into a table in the kernel image
(between __start_mcount_loc and __stop_mcount_loc) for later use by ftrace.
This patch adds arm64 specific definitions to identify such locations.
There are two types of implementation, C and Perl. On arm64, only C version
is used to build the kernel now that CONFIG_HAVE_C_RECORDMCOUNT is on.
But Perl version is also maintained.
This patch also contains a workaround just in case where a header file,
elf.h, on host machine doesn't have definitions of EM_AARCH64 nor
R_AARCH64_ABS64. Without them, compiling C version of recordmcount will
fail.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This matches the existing behavior in arch/tile/Makefile for defconfig.
Reported-by: fengguang.wu@intel.com
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Tony Lu <zlu@tilera.com>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
With gcc 4.6.0 the -mfentry feature places the function profiling call
at the start of the function. When this is used, the call is to
__fentry__ and not mcount. This is required for Ksplice as the C
version of recordmcount doesn't insert section symbols for the
__mcount_loc section so we fall back to the perl version.
Based on 48bb5dc6cd (ftrace: Make
recordmcount.c handle __fentry__).
Link: http://lkml.kernel.org/r/1383648129-10724-1-git-send-email-jamie.iles@oracle.com
Signed-off-by: Jamie Iles <jamie.iles@oracle.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit adds support for static ftrace, graph function support,
and dynamic tracer support.
Signed-off-by: Tony Lu <zlu@tilera.com>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Do the mcount offset adjustment in the recordmcount.pl/recordmcount.[ch]
at compile time and not in ftrace_call_adjust at run time.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Do the mcount offset adjustment in the recordmcount.pl/recordmcount.[ch]
at compile time and not in ftrace_call_adjust at run time.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The .kprobe.text section is safe to modify mcount to nop and tracing.
Add it to the whitelist in recordmcount.c and recordmcount.pl.
Cc: John Reiser <jreiser@bitwagon.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/20110421023737.743350547@goodmis.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The section .ref.text will not go away unexpectedly and is
safe to trace. Add it to the safe list of sections to allow
tracing.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Handle the different nop and call instructions for Thumb-2. Also, we
need to adjust the recorded mcount_loc addresses because they have the
lsb set.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org> [recordmcount.pl change]
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This adds mcount recording and updates dynamic ftrace for ARM to work
with the new ftrace dyamic tracing implementation. It also adds support
for the mcount format used by newer ARM compilers.
With dynamic tracing, mcount() is implemented as a nop. Callsites are
patched on startup with nops, and dynamically patched to call to the
ftrace_caller() routine as needed.
Acked-by: Steven Rostedt <rostedt@goodmis.org> [recordmcount.pl change]
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The mcount call on Blackfin systems includes some stack manipulation
around the actual call site, so extend the build time perl script to
support this. This way we can avoid doing the calculation at runtime.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
LKML-Reference: <1281079584-21205-1-git-send-email-vapier@gentoo.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
I found this issue in a locally patched 2.6.32.x, current kernels have
moved the offending code to an __init function which is skipped by
recordmcount.pl, so the bug is not currently being exercised.
However, I think the patch is still a good idea, to avoid future
problems if _mcount were to ever have its address taken in normal
code.
This is what I originally saw:
Although arch/mips/kernel/ftrace.c is built without -pg, and thus
contains no calls to _mcount, it does use the address of _mcount
in ftrace_make_nop(). This was causing relocations to be emitted
for _mcount which recordmcount.pl erronously took to be _mcount
call sites. The result was that the text of ftrace_make_nop()
would be patched with garbage leading to a system crash.
In non-module code, all _mcount call sites will have R_MIPS_26
relocations, so we restrict $mcount_regex to only match on these.
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
LKML-Reference: <1278712325-12050-1-git-send-email-ddaney@caviumnetworks.com>
Cc: Li Hong <lihong.hi@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Let the arch argument be overruled by bits. Otherwise, building of
external modules against a i386 target on a x86-64 host (and likely vice
versa as well) fails unless ARCH=i386 is explicitly passed to make.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
LKML-Reference: <4B4AFE10.8050109@siemens.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Modified recordmcount.pl to use perl constructs that are still
understandable by C hackers that are not perl programmers.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
LKML-Reference: <1262724082-9517-1-git-send-email-w.sang@pengutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
- move check for open file in front of the writing loop
- use perl-constructs to access the array
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
LKML-Reference: <1262716072-14414-2-git-send-email-w.sang@pengutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
With dynamic function tracer, by default, _mcount is defined as an
"empty" function, it returns directly without any more action . When
enabling it in user-space, it will jump to a real tracing
function(ftrace_caller), and do the real job for us.
Differ from the static function tracer, dynamic function tracer provides
two functions ftrace_make_call()/ftrace_make_nop() to enable/disable the
tracing of some indicated kernel functions(set_ftrace_filter).
In the -v4 version, the implementation of this support is basically the same as
X86 version does: _mcount is implemented as an empty function and ftrace_caller
is implemented as a real tracing function respectively.
But in this version, to support module tracing with the help of
-mlong-calls in arch/mips/Makefile:
MODFLAGS += -mlong-calls.
The stuff becomes a little more complex. We need to cope with two
different type of calling to _mcount.
For the kernel part, the calling to _mcount(result of "objdump -hdr
vmlinux"). is like this:
108: 03e0082d move at,ra
10c: 0c000000 jal 0 <fpcsr_pending>
10c: R_MIPS_26 _mcount
10c: R_MIPS_NONE *ABS*
10c: R_MIPS_NONE *ABS*
110: 00020021 nop
For the module with -mlong-calls, it looks like this:
c: 3c030000 lui v1,0x0
c: R_MIPS_HI16 _mcount
c: R_MIPS_NONE *ABS*
c: R_MIPS_NONE *ABS*
10: 64630000 daddiu v1,v1,0
10: R_MIPS_LO16 _mcount
10: R_MIPS_NONE *ABS*
10: R_MIPS_NONE *ABS*
14: 03e0082d move at,ra
18: 0060f809 jalr v1
In the kernel version, there is only one "_mcount" string for every
kernel function, so, we just need to match this one in mcount_regex of
scripts/recordmcount.pl, but in the module version, we need to choose
one of the two to match. Herein, I choose the first one with
"R_MIPS_HI16 _mcount".
and In the kernel verion, without module tracing support, we just need
to replace "jal _mcount" by "jal ftrace_caller" to do real tracing, and
filter the tracing of some kernel functions via replacing it by a nop
instruction.
but as we have described before, the instruction "jal ftrace_caller" only left
32bit length for the address of ftrace_caller, it will fail when calling from
the module space. so, herein, we must replace something else.
the basic idea is loading the address of ftrace_caller to v1 via changing these
two instructions:
lui v1,0x0
addiu v1,v1,0
If we want to enable the tracing, we need to replace the above instructions to:
lui v1, HI_16BIT_ftrace_caller
addiu v1, v1, LOW_16BIT_ftrace_caller
If we want to stop the tracing of the indicated kernel functions, we
just need to replace the "jalr v1" to a nop instruction. but we need to
replace two instructions and encode the above two instructions
oursevles.
Is there a simpler solution? Yes! Here it is, in this version, we put _mcount
and ftrace_caller together, which means the address of _mcount and
ftrace_caller is the same:
_mcount:
ftrace_caller:
j ftrace_stub
nop
...(do real tracing here)...
ftrace_stub:
jr ra
move ra, at
By default, the kernel functions call _mcount, and then jump to ftrace_stub and
return. and when we want to do real tracing, we just need to remove that "j
ftrace_stub", and it will run through the two "nop" instructions and then do
the real tracing job.
what about filtering job? we just need to do this:
lui v1, hi_16bit_of_mcount <--> b 1f (0x10000004)
addiu v1, v1, low_16bit_of_mcount
move at, ra
jalr v1
nop
1f: (rec->ip + 12)
In linux-mips64, there will be some local symbols, whose name are
prefixed by $L, which need to be filtered. thanks goes to Steven for
writing the mips64-specific function_regex.
In a conclusion, with RISC, things becomes easier with such a "stupid"
trick, RISC is something like K.I.S.S, and also, there are lots of
"simple" tricks in the whole ftrace support, thanks goes to Steven and
the other folks for providing such a wonderful tracing framework!
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.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/675/
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Steven Rostedt
Nathan Chancellor
Linus Torvalds
Masahiro Yamada
Rong Chen
Vasily Gorbik
Thomas Gleixner
Daniel Dadap
Guo Ren
Joe Lawrence
Zong Li
Nicholas Piggin
Alan Kao
Arnd Bergmann
Kamil Rytarowski
Masahiro Yamada
Chris Metcalf
Dmitry Vyukov
Ulrich Weigand
Heiko Carstens
Michael Karcher
AKASHI Takahiro
Tony Lu
Jamie Iles
Martin Schwidefsky
Steven Rostedt
Rabin Vincent
Mike Frysinger
David Daney
Ingo Molnar
Jan Kiszka
Wolfram Sang
Wu Zhangjin