After Linux commit 47cdd64be483 ("dynamic_debug: refactor
dynamic_pr_debug and friends"), the name of the static local variable
used for dynamic printks is no longer "descriptor".
Make the is_special_static() check broader such that it doesn't care
about the variable name, and just whitelists any variable in the
__verbose section.
Fixes#990.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Starting with binutils 2.31, the Linux kernel may have R_X86_64_PLT32
relocations. Make sure we support them. This should be as simple as
treating R_X86_64_PLT32 exactly like R_X86_64_PC32 everywhere. For more
details see upstream commit torvalds/linux@b21ebf2.
This also fixes the following issue seen on Fedora 29:
```
$ kpatch-build/kpatch-build -t vmlinux ./test/integration/fedora-27/convert-global-local.patch
Using cache at /home/jpoimboe/.kpatch/src
Testing patch file(s)
Reading special section data
Building original source
Building patched source
Extracting new and modified ELF sections
ERROR: slub.o: 1 function(s) can not be patched
slub.o: function __kmalloc has no fentry/mcount call, unable to patch
/home/jpoimboe/git/kpatch/kpatch-build/create-diff-object: unreconcilable difference
ERROR: 1 error(s) encountered. Check /home/jpoimboe/.kpatch/build.log for more details.
```
Fixes#975.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Currently we do not support changes to functions referring to any of the
*_fixup sections on ppc64le. This patch introduces check for such
changes during the patchability check, where we abort building the
patch module.
This patch implements the phase 1 fix of 3 phases discussed at
https://github.com/dynup/kpatch/issues/974:
"
Phase 1 fix:
For kernel versions which don't have livepatch-specific powerpc code
(currently all kernel versions), kpatch-build needs to assert an error
if it detects that one of the following sections refers to a patched
function: __ftr_fixup, __mmu_ftr_fixup, __fw_ftr_fixup.
"
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Add support for __spec_barrier_fixup (barrier nospec fixup) special
section on ppc64le.
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Fix the size of special group __lwsync_fixup on ppc64le.
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
commit f8213c87f6 ("lookup: Fix format string for symtab_read() on
PPC64LE") fixed the symbol table lookup when readelf adds ppc64le
"[<localentry>: 8]" info for functions like so:
23: 0000000000000008 96 FUNC LOCAL DEFAULT [<localentry>: 8] 4 cmdline_proc_show
however, it seems that readelf 2.30-57.el8 displays this in a slightly
different format:
24493: c000000000587970 96 FUNC LOCAL DEFAULT 2 cmdline_proc_show [<localentry>: 8]
Instead of adding more cases to kpatch-build's lookup.c scanf format,
let's just delete this information from the symtab file with a quick and
dirty sed regex. This allows us to handle both observed cases (and
perhaps others) while removing the arch-specific scanf formatting in
lookup.c
Fixes: f8213c87f6 ("lookup: Fix format string for symtab_read() on PPC64LE")
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
commit 767d9669bd ("kpatch-build: use readelf instead of eu-readelf")
replaced eu-readelf with readelf for constructing symbol table. The
format of symbol table entries differs a little on Power when the symbol
is a function with binding type LOCAL. For example, consider:
23: 0000000000000008 96 FUNC LOCAL DEFAULT [<localentry>: 8] 4 cmdline_proc_show
An extra column preceding index of the symbol denoting symbol value to
be local entry point offset of the function is printed, with the
current sscanf format string in lookup::symtab_read the values will
mismatch ending with in accurate lookup table getting constructed. This
patch fixes it by introducing an Power specific format string for
function symbols with bind type LOCAL.
Fixes: 767d9669 ("kpatch-build: use readelf instead of eu-readelf")
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
kpatch-elf::create_section_pair would create new rela section, and the
relasec->data->d_type is not set, which is a random value, and it will
use in kpatch-elf::kpatch_write_output_elf
data->d_type = sec->data->d_type;
which would cause Segmentation fault in kpatch_write_output_elf::elf_update.
Program received signal SIGSEGV, Segmentation fault.
(gdb) bt
0 0x00007ffff7bcd8d2 in __elf64_updatefile at elf64_updatefile.c
1 0x00007ffff7bc9bed in write_file at elf_update.c
2 0x00007ffff7bc9f16 in elf_update at elf_update.c
3 0x000000000040ca3d in kpatch_write_output_elf at kpatch-elf.c
4 0x0000000000409a92 in main at create-diff-object.c
Signed-off-by: chenzefeng <chenzefeng2@huawei.com>
readelf is more standard, using readelf insteaded we should solve there
issues:
First, using "readelf -s", the symbol name would truncated by 25 chars,
to solve this issue, add option "--wide".
Second, the size may be mixed of decimal and hex, we get the size by "%s",
and use strtoul(size, NULL, 0) to convert the size.
Third, the symbol type is SHN_UNDE, the Ndx display "UND", so changed to
compare with "UND".
Signed-off-by: chenzefeng <chenzefeng2@huawei.com>
.altinstr_replacement section may have relocation symbols which need to
be included, therefore we should call kpatch_include_symbol() to ensure
that its section is included as well.
The special section processing should also occur before
kpatch_print_changes() to provide accurate logging info.
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
kpatch-elf::kpatch_write_output_elf will call the gelf_getclass()
to acquire the output elf's class. But the input parameter kelf->elf
is NULL, the gelf_getclass(kelf->elf) will return ELFCLASSNONE, not
the value we expect ELFCLASS32 or ELFCLASS64.
the gelf_getclass function code:
int
gelf_getclass (Elf *elf)
{
return elf == NULL || elf->kind != ELF_K_ELF ? ELFCLASSNONE : elf->class;
}
the gelf_newehdr fuction code:
void *
gelf_newehdr (Elf *elf, int class)
{
return (class == ELFCLASS32
? (void *) INTUSE(elf32_newehdr) (elf)
: (void *) INTUSE(elf64_newehdr) (elf));
}
Luckily, when we create a patch for x86_64 or powerpc64, if we pass the
ELFCLASSNONE for the function gelf_newehdr, it will return elf64_newehdr,
so don't cause the fault. But it's better to use the gelf_getclass(elf)
instead of gelf_getclass(kelf->elf).
Signed-off-by: chenzefeng <chenzefeng2@huawei.com>
make check using shellcheck version 0.6.0 suggests following
improvements:
In kpatch/kpatch line 160:
if [[ ! -z "$checksum" ]] && [[ -e "$SYSFS/${modname}/checksum"]] ; then
^-- SC2236: Use -n instead of ! -z.
In kpatch-build/kpatch-build line 953:
[[ ! -z "$UNDEFINED" ]] && die "Undefined symbols: $UNDEFINED"
^-- SC2236: Use -n instead of ! -z.
'-n' and '! -z' are used interchangeably across the scripts, let's use
'-n' consistently to check a non-empty string instead of using negation.
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
The create-diff-object.c create intermediate ".kpatch.relocations"
sections instead of ".kpatch.dynrelas" sections, and add a new
section ".rela.kpatch.symbols", so we should update the conditions
in function kpatch_create_intermediate_sections for these changed.
Fixes: 87643703a7 ("create-diff-object: create .kpatch.relocations and .kpatch.symbols sections")
Signed-off-by: chenzefeng <chenzefeng2@huawei.com>
After changing the gcc name in a linux tree to gcc72, kpatch-build failed to
produce hotpatches with the error message "ERROR: no changed objects found."
This is due to a wrapper script called kpatch-gcc, called while kpatch-build
builds the kernel, which checks if the compiler name matches exactly gcc,
failing the check when comparing to gcc72, and thus not producing the expected
file changed_objs containing the list of changed objects.
This commit fixes this issue by loosening the check on the gcc name.
Signed-off-by: Bruno Loreto <loretob@amazon.com>
Reviewed-by: Bjoern Doebel <doebel@amazon.com>
Reviewed-by: Amit Shah <aams@amazon.com>
Reviewed-by: Pawel Wieczorkiewicz <wipawel@amazon.com>
The kpatch-build :: find_parent_obj() function's "deep find" may
failed to find objects if they are not located in current directory:
ERROR: invalid ancestor xxx/xxx.o for xxx/xxx.o.
This is reproducable when building an out-of-tree module of the
following structure:
wwheart@linux41:~/helloworld 0 > tree -a
.
├── buffer_overflow1.ko
├── .buffer_overflow1.ko.cmd
├── buffer_overflow1.mod.c
├── buffer_overflow1.mod.o
├── .buffer_overflow1.mod.o.cmd
├── buffer_overflow1.o
├── .buffer_overflow1.o.cmd
├── hello.c
├── hello.o
├── .hello.o.cmd
├── Makefile
├── modules.order
├── Module.symvers
├── test.patch
├── .tmp_versions
│ └── buffer_overflow1.mod
└── xxx
├── xxx.c
├── xxx.h
├── xxx.o
└── .xxx.o.cmd
wwheart@linux41:~/helloworld 0 > cat test.patch
diff --git a/xxx/xxx.c b/xxx/xxx.c
index aab3c67..d81ad00 100644
--- a/xxx/xxx.c
+++ b/xxx/xxx.c
@@ -1,6 +1,7 @@
#include <linux/kernel.h>
void czf_test(void)
{
+ printk("livepatch test\n");
printk("xxx\n");
}
wwheart@linux41:~/helloworld 0 > cat Makefile
obj-m += buffer_overflow1.o
buffer_overflow1-y += hello.o xxx/xxx.o
Modify the deep find to traverse sub-directories in order to search
the entire tree instead of only the current directory.
Fixes: 8c2792af6c ("kpatch-build: deep find performance improvement")
Signed-off-by: chenzefeng <chenzefeng2@huawei.com>
reason: The strdup() function returns a pointer to a new string
which is a duplicate of the string s. Memory for the
new string is obtained with malloc, and can be freed
with free.
here, fix memleak by removing the strdup.
Signed-off-by: chenzefeng <chenzefeng2@huawei.com>
reason: Firstly, in the function lookup_open use the malloc to
allocate some memory, but call the function lookup_close
to free the memory.
Secondly, table->obj_sym->name, table->exp_sym->name and
table->exp_sym->objname used the strdup, so them should
free also.
Thirdly, adjust the order of make_nodname, if not, it
will cause an exception when free(exp_sym->objname) in
lookup_close.
Signed-off-by: chenzefeng <chenzefeng2@huawei.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>
When building out-of-tree modules, gcc may be passed full source
pathnames (like /home/user/testmod/testmod.c). Adjust the filepath
filtering in kpatch-gcc to match against files relative to the
KPATCH_GCC_SRCDIR / kpatch-build SRCDIR prefix.
Fixes: #941
Signed-off-by: Joe Lawrence <joe.lawrence@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>
For fun I tried to create a livepatch of upstream patch
ad211f3e94b314a910d4af03178a0b52a7d1ee0a for my kernel. This
caused kpatch-build to fail with a NULL pointer derefence because
base_locals was NULL (returned via kpatch_elf_locals(), which
can return a NULL pointer). This patch fixes the SIGSEGV
via a NULL check. The end result is a live patch is created
and loaded.
Signed-off-by: Balbir singh <bsingharora@gmail.com>
kpatch_mark_ignored_sections include .rodata.str1.1 section but does
not include its section symbol, causing its section symbol can not be
included any more in kpatch_include_standard_elements. After the
section symbol is freed in kpatch_elf_teardown, we got a segmentation
fault in kpatch_create_intermediate_sections.
Signed-off-by: Zhipeng Xie <xiezhipeng1@huawei.com>
Both generate randomly modified object files on each build. This breaks
comparing original and patched object file. See also #924.
Signed-off-by: Simon Ruderich <simon@ruderich.org>
Prevents the following shellcheck warning:
In kpatch-build/kpatch-build line 583:
which yumdownloader &>/dev/null || die "yumdownloader (yum-utils or dnf-utils) not installed"
^-- SC2230: which is non-standard. Use builtin 'command -v' instead.
Signed-off-by: Simon Ruderich <simon@ruderich.org>
As discovered in #918, the `__FUNCTION__` static local variable is
similar to the `__func__` variable, in that it refers to the current
function name.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Sometimes due to config-dependency issues or other reasons whole
object-files would get optimized out from final vmlinux/module, in cases
like this create-diff-object would fail during symbol lookup table
creation in lookup_open(). Because lookup_open() call is situated before
we established that objectfile has changed this triggers not only on
real problems, but also during mass-rebulds caused by changes to
header-files. While it usually indicates a real issue with config this
should not prevent kpatch from building.
Move lookup_open() call so that it is called only for changed
object-files.
Fixes#910
Signed-off-by: Artem Savkov <asavkov@redhat.com>
strdup symbol names in kpatch_elf_locals and when noting down hint
instead of just copying pointers so that they are still usable after
we teardown/free kelf_base.
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Starting with 1b1eeca7e4c1 "init: allow initcall tables to be emitted using
relative references" [1] __init functions are generating an "__addressable_"
symbol in a ".discarded.addressable" section so it does not show up in final
vmlinux triggering find_local_syms failures. Add "_addressable_" to the list
in maybe_discarded_sym().
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1b1eeca7e4c19fa76d409d4c7b338dba21f2df45
Signed-off-by: Artem Savkov <asavkov@redhat.com>
symtab_read() would previously skip entries with blank names resulting
in some of important entries being skipped. For instance vmlinux file
has an STT_FILE entry at the end with a blank name that contains global
offset table. Because it was skipped all of the global entries from this
table were considered a part of previous processed file resulting in
create-diff-object failing in find_local_syms().
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Nothing critical, but find_special_section_data_ppc64le() could run
longer than needed: the exit condition was not met after all the values
had been found.
Fixes: 77f8fd09 "kpatch-build: ppc64le - Add special section support"
Signed-off-by: Evgenii Shatokhin <eshatokhin@virtuozzo.com>
GCC puts the constant variable requiring relocation into .data.rel. or
.data.rel.ro depending upon the bind type of the symbol. Extend
is_bundledable() to check these .data sections too.
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
- Future releases of RHEL / CentOS will provide the yumdownloader
program with the 'dnf-utils' package (not 'yum-utils'). Instead of
looking to see that the package is installed, just look for the
program itself.
- RHEL / CentOS 8 kernel release names (as returned by 'uname -r') may
not match the SRPM buildroot release subdirectory name. Relax the
wildcard when moving this directory to $SRCDIR.
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
4.18 adds -mcount-record to KBUILD_FLAGS when supported by the compiler.
This results in most of kpatch_create_mcount_sections()'s work being
already done, so we can at least skip the last part of it that updates
the first instruction in patched functions.
Signed-off-by: Artem Savkov <asavkov@redhat.com>
In Ubuntu 18.04 LTS (but not in 16.04 LTS), the "linux" source package
no longer builds the "linux-image-*" binary kernel image packages
directly, but instead, it produces the "linux-image-unsigned-*" binary
packages, and the "linux-signed" source package then produces the
(signed) "linux-image-*" binary packages from the unsigned binaries.
This means that querying the target kernel's linux-image-* package for
its source package will yield a source package that is just a wrapper,
and does not actually contain the kernel source code.
Deal with this by removing the "-signed" substring from the kernel
source package name if it is present. This makes kpatch-build work
on Ubuntu 18.04.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Commit d86c1113cc ("kpatch-build: less aggressive clean_cache()")
broke clean_cache(). Instead of expanding the wildcard, it tries to
delete a file named '*'.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
According to gcc8's man pages gcc can put functions into .text.unlikely
or .text.hot subfunctions during optimization. Add ".text.hot" to the
list of bundleable functions in is_bundleable().
Signed-off-by: Artem Savkov <asavkov@redhat.com>
gcc8 can place functions to .text.unlikely and .text.hot subsections
during optimizations. Allow symbols to change subsections instead of
failing.
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Add a function that would detect parent/child symbol relations. So far
it only supports .cold.* symbols as children.
Signed-off-by: Artem Savkov <asavkov@redhat.com>
kpatch-build detects RHEL-ALT kernel support by looking for a ".el7a."
substring in the kernel release string. Look for that substring in the
unchanged $ARCHVERSION instead of $KVER, which may not have the
trailing '.' character that our regex expects.
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Source RPMs don't have an architecture associated with them, so to avoid
confusion, drop that part of the kernel release string when calling
yumdownloader.
Fixes#887.
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Some of the provisioned machines I sometimes use don't have enough
diskspace for a full kpatch-patch build in home partition. I usually
solve this by symlinking .kpatch(and .ccache) dirs to a different
partition, however this only works with -s option because of
clean_cache().
clean_cache() currently removes .kpatch directory completely, recreating
it from scratch, change it to only remove the contents of the directory
instead.
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Building with GCC 7.3.0 on Debian sid fails with the following error:
gcc -g -O2 -fdebug-prefix-map=/build/kpatch-0.6.0=. -fstack-protector-strong -Wformat -Werror=format-security -MMD -MP -I../kmod/patch -Iinsn -Wall -Wsign-compare -g -Werror -Wdate-time -D_FORTIFY_SOURCE=2 -c -c
create-diff-object.c: In function 'kpatch_compare_correlated_rela_section':
create-diff-object.c:316:20: error: 'toc_data1' may be used uninitialized in this function [-Werror=maybe-uninitialized]
return toc_data1 == toc_data2;
~~~~~~~~~~^~~~~~~~~~~~
create-diff-object.c:256:16: note: 'toc_data1' was declared here
unsigned long toc_data1, toc_data2;
^~~~~~~~~
cc1: all warnings being treated as errors
This is a false positive as the code only compares those two values
after initializing them. But lets keep GCC happy.
Signed-off-by: Simon Ruderich <simon@ruderich.org>
If $AWK_OPTIONS are blank gawk would treat "" as a blank script
resulting in none of the special struct being detected.
Fixes: 1330dcc "create-diff-object: add ORC section support"
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Convert magic exit status values into a common enum for clarity.
Suggested-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
None of the lib/* file are built with fentry calls, so we can't patch
them. Add these files to the list that kpatch-gcc skips.
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Add a little more context ("in the vmlinux symbol table") to the
symbol-not-found message in find_local_syms().
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Change the "FILE symbol not found in base. Stripped?" (fatal) error
message into a warning. These crop up whenever a change is made to an
assembly file.
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Finally add support for processing the ORC unwinder sections.
The ORC unwinder sections are more special than the other special
sections, so they need their own dedicated function to process them,
though the code is similar to kpatch_regenerate_special_sections().
BTW, upstream livepatch still doesn't support the ORC unwinder. That
change will be coming soon (probably Linux 4.19).
Fixes#785.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Since the codeset supports just the 64 bit variant, lets move
to __powerpc64__ and use it. I checked the ABI doc as well
and the kernel/gcc.
Signed-off-by: Balbir singh <bsingharora@gmail.com>
As discussed in #848, there is no known reason to do "make mrproper" on
every build. It seems to be an artifact from previous iterations (we
used to use 'O=' to build the kernel in a separate object tree.
It has many downsides:
- massive performance degradation
- breaks the '-t' option
- prevents the user from manually saving/restoring ~/.kpatch
Only do it where it's really needed, which is after first extracting the
source from an RPM.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
"make mrproper" combined with the '-t' flag is dangerous, as it results
in the Module.symvers file getting truncated, which causes
create-diff-object to create some funky dynrelas. Detect this condition
in kpatch-build and error out.
We will hopefully also be removing "make mrproper" soon, which will make
'-t' even more useful.
Fixes#589.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
In recent versions of Fedora, when building from a source RPM,
kpatch-build fails because it can't find the .config file. Get the file
from the canonical location: the configs subdirectory.
This also works with older versions of Fedora and RHEL, and ensures we
always have the right config file for the arch we're building for.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Before we were adding the undefined symbols to the lookup table, but we
were skipping them by setting the sym.skip flag.
With 3aa5abb807 ("kpatch-build: use symbol table instead of kobject"),
the skip flag was removed but the undefined symbol check was removed
with it.
The skip flag can remain gone. Instead of adding undefined symbols to
the table and skipping them when iterating the table, just don't add
them to start with.
Also make the sscanf conditional lines identical, to ease maintenance.
Fixes#869.
Fixes: 3aa5abb807 ("kpatch-build: use symbol table instead of kobject")
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Deal with a few RHEL kernel-alt quirks for ppc64le:
- The RPM and spec names are "kernel-alt".
- 7.6 ALT is based on 4.14 but it doesn't have the 'immediate' flag.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
gcc8 introduces ".cold." optimization symbols that have arbitrary
trainling numbers in their names just like ".isra." and others.
Add ".cold." to a condition in kpatch_rename_mangled_functions()
Signed-off-by: Artem Savkov <asavkov@redhat.com>
plugin compilation fails on GCC 8:
In file included from gcc-plugins/gcc-common.h:100,
from gcc-plugins/ppc64le-plugin.c:1:
/usr/lib/gcc/powerpc64le-linux-gnu/8/plugin/include/attribs.h: In function ‘tree_node* canonicalize_attr_name(tree)’:
/usr/lib/gcc/powerpc64le-linux-gnu/8/plugin/include/attribs.h:118:11: error: ‘get_identifier_with_length’ was not declared in this scope
return get_identifier_with_length (s + 2, l - 4);
^~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/powerpc64le-linux-gnu/8/plugin/include/attribs.h:118:11: note: suggested alternative: ‘get_attr_min_length’
return get_identifier_with_length (s + 2, l - 4);
^~~~~~~~~~~~~~~~~~~~~~~~~~
get_attr_min_length
Makefile:34: recipe for target 'gcc-plugins/ppc64le-plugin.so' failed
get_identifier_with_length() is defined under stringpool.h, include this
header file for GCC 8, before including attribs.h
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
When I made a patch to the nfsd module on a ppc64le system with a RHEL 7
based kernel, livepatch prevented the target module from loading with:
livepatch: symbol '.TOC.' not found in symbol table
References to this symbol are treated specially by the kernel module
loader, so references to it should never be converted to dynrelas.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
While building a gcc-consprop patch from integration tests gcc8 would place a
__timekeeping_inject_sleeptime.constprop.18.cold.27 symbol into
.text.unlikely.__timekeeping_inject_sleeptime.constprop.18 section. Because
section name doesn't have the '.cold.27' suffix this symbol fails
is_bundleable() check while still being bundleable and later exits early in
kpatch_rename_mangled_functions() without renaming the corresponding patched
function. All of this results in a create-diff-object errror:
ERROR: timekeeping.o: symbol changed sections: __timekeeping_inject_sleeptime.constprop.18.cold.27
/home/asavkov/dev/kpatch/kpatch-build/create-diff-object: unreconcilable difference
Fix by ignoring .cold.* name suffix in is_bundleable() for.text.unlikely
sections.
Signed-off-by: Artem Savkov <asavkov@redhat.com>
From Oracle's Linker and Libraries Guide [1]:
"The symbols in a symbol table are written in the following order ...
The global symbols immediately follow the local symbols in the symbol
table. The first global symbol is identified by the symbol table sh_info
value. Local and global symbols are always kept separate in this manner,
and cannot be mixed together."
[1] https://docs.oracle.com/cd/E19120-01/open.solaris/819-0690/chapter6-79797/index.htmlFixes#854.
Signed-off-by: Joe Lawrence <joe.lawrence@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>
Use named variables instead of cmdline argument indexes so that it is
easier to read create-diff-object.c.
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 the `__LINE__` macro detection heuristics based on recent kernel
changes:
- __warn_printk(), used in the WARN macros, which put the line number in
%edx
- __might_fault(), used in the usercopy macros
- lockdep_rcu_suspicious(), used in the RCU_LOCKDEP_WARN macro
- printk(), used in the ASSERT_RTNL macro
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
