Add the __mcount_loc section on ppc64le. It has pointers to all the
mcount calls. This will enable the ftrace hook to be used for patched
functions.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com> (rebased)
Some theoretically unchanged functions can have undesired changes if the
compiler decides to perform inlining in a different way (e.g. because of
newly added references). In such a case, it can be useful to discard
changes to functions that don't actually need modification.
Sadly, this currently doesn't work for functions missing the ftrace hook
(e.g. notrace code) as presence of the hook is checked before
identifying elements to ignore.
Look for functions/sections to ignore earlier.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
The current code to find the twin of a local static variable allows two
variables of the same name to be wrongly matched with the other's twin.
While there isn't a magic formula to avoid this, make stricter
requirements for twining static local from the original object with
a symbol from the patched object. This reduces the risk of erroneous
matches.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
The RHEL powerpc kernel is compiled with -O3, which triggers some
"interesting" new optimizations. One of them, which seems to be
relatively common, is the replacing of a function with two separate
"constprop" functions.
Previously we only ever saw a single constprop clone, so we just renamed
the patched version of the function to match the original version. Now
that we can have two such clones, that no longer makes sense.
Instead of renaming functions, just improve the correlation logic such
that they can be correlated despite having slightly different symbol
names. The first clone in the original object is correlated with the
first clone in the patched object; the second clone is correlated with
the second clone; and so on.
This assumes that the order of the symbols and sections doesn't change,
which seems to be a reasonable assumption based on past experience with
the compiler. Otherwise it will just unnecessarily mark the cloned
constprop functions as changed, which is annoying but harmless, and
noticeable by a human anyway.
Fixes#935.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
While static keys (jump labels) are currently broken in livepatch, a
broken dynamic debug static key is harmless since it just disables
dynamically enabled debug printks in the patched code.
Fixes: #1021
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Use make's .DELETE_ON_ERROR special target to make sure we don't have
any .OUTPUT.o leftovers for failed tests.
Fixes: #999
Signed-off-by: Artem Savkov <asavkov@redhat.com>
The ppc64le unit tests are failing because the lookup code is getting
confused by the "[<localentry>: 8]" string in the readelf symbol table
output.
Remove the string so the lookup code can parse it correctly.
kpatch-build already uses the same sed, so they should match.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Make 3.8 doesn't support the "file" function, which is used by the unit
test Makefile to output the contents of a custom env file, if one
exists. Use shell instead.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
"make unit" automatically rebases the submodule, which causes a lot of
surprises. Instead, just print a warning if it's out of date.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
readelf is more standard, using readelf insteaded
test/difftree.sh: the symbol name may be with "FILE", which may be
get a incorrect count, here add "awk".
test/unit/Makefile.include: use "readelf -s --wide" instead of
"eu-readelf -s".
Signed-off-by: chenzefeng <chenzefeng2@huawei.com>
Some unit tests may need debug symbols to reproduce problems (see
issue #928 for example), so skip the unit-test Makefile.include
check_stripped call for objects that include "NOSTRIP" in their
filename.
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
This reverts commit 87c64519fc.
The jump label support doesn't work with upstream livepatch. Joe
Lawrence found the following ordering issue:
load_module
apply_relocations
/* Livepatch relocation sections are applied by livepatch */
if (info->sechdrs[i].sh_flags & SHF_RELA_LIVEPATCH)
continue;
post_relocation
module_finalize
jump_label_apply_nops << crash
...
do_init_module
do_one_initcall(mod->init)
__init patch_init [kpatch-patch]
klp_register_patch
klp_init_patch
klp_init_object
klp_init_object_loaded
klp_write_object_relocations
So jump_label_apply_nops() is called *before*
klp_write_object_relocations() has had a chance to write the klp
relocations (.klp.rela.kvm_intel.__jump_table, for example).
We need to resolve this upstream first.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Add support for jump labels, also known as static jumps, static keys,
static branches, and jump tables. Luckily,
kpatch_process_special_sections() is already generic enough to make this
an easy fix.
Fixes: #931
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Add support for optional <test-name>.env files that contain additional
environment variables. This can also be used to override per-arch env
vars we have because last value assigned will be used.
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Bump unit-test-objs submodule head pointer to include latest test:
f82c458 x86_64: added a test for a function that uses _THIS_IP_
4a097d9 ppc64le: Test const var requiring .data.rel relocation
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Update submodule pointer to include new gcc8 unit tests.
This update also includes unit-test for https://github.com/dynup/kpatch/pull/892
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Don't try to call unittest clean if objfile dir is non-existant (e.g.
when objfile submodule wasn't cloned). Another solution would be to make
clean target dependant on objdir but that would mean downloading a lot
of unneeded data for users who don't run unit-tests.
Fixes: #872
Signed-off-by: Artem Savkov <asavkov@redhat.com>
This fixes the following error with an older version of git
(1.8.3.1):
make -C test/unit
make[1]: Entering directory `/root/kpatch/test/unit'
git submodule update --init --rebase
You need to run this command from the toplevel of the working tree.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
create-diff-object doesn't really need the full kernel object file as
input. All it requires is a symbol table. Switch to using "eu-readelf -s"'s
output instead of object files. This will enable us to cover more cases
in unit tests.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Artem Savkov <asavkov@redhat.com>
ppc64le lacked kpatch_line_macro_change_only() implementation. Add one
based on x86_64 version and available unit tests.
Fixes: #843
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Update submodule to 6774fbc "ppc64le: initial object files"
Remove CDO_ENV since it is moved to per-arch makefiles.
Signed-off-by: Artem Savkov <asavkov@redhat.com>
While convenient git-lfs has too many restrictions for kpatch's needs.
Remove links to the objectfiles and related configs.
Signed-off-by: Artem Savkov <asavkov@redhat.com>
I placed the library in the top-level test directory, as the same
assertions could also be used by the integration tests once we rework
them a bit.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
As an extra sanity check, ensure the number of patched functions never
changes.
Also added a test for convert-global-local to ensure the global symbol
is converted to a local.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Broaden the impact of the 'clean' target so that output objects will
still get cleaned when when old tests get removed or renamed.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
After doing some research, I've discovered that most of these tests no
longer test what they were originally intended to test.
An exception here is the 'macro-hooks' test, which is probably better
suited as an integration test, so I removed its unit test and kept its
integration test.
Really, most of these tests weren't all that useful to begin with, so
it's not a big loss. The one exception is 'gcc-static-local-var-2',
which was originally meant to test multiple static local variables with
the same name in the name function. That's a good thing, so I'll try to
come up with another test for that which works with Linux 4.16.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
With #755, we started using dynrelas for function pointers. However,
this behavior only makes sense for function pointers to existing
functions. For function pointers to *new* functions, just use a normal
rela.
The 'function-ptr-new' unit test is from the following patch:
https://github.com/dynup/kpatch/files/1927198/new-static-callback.patch.txtFixes#834.
Fixes: 495e619750 ("kpatch-build, x86: do not use the patched functions as callbacks directly")
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Don't suppress stderr in the non-fail unit tests so that
create-diff-object error messages will be printed.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
