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* Merge tag 'modules-6.6-rc1' of ↵Linus Torvalds2023-08-291-4/+18
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull modules updates from Luis Chamberlain: "Summary of the changes worth highlighting from most interesting to boring below: - Christoph Hellwig's symbol_get() fix to Nvidia's efforts to circumvent the protection he put in place in year 2020 to prevent proprietary modules from using GPL only symbols, and also ensuring proprietary modules which export symbols grandfather their taint. That was done through year 2020 commit 262e6ae7081d ("modules: inherit TAINT_PROPRIETARY_MODULE"). Christoph's new fix is done by clarifing __symbol_get() was only ever intended to prevent module reference loops by Linux kernel modules and so making it only find symbols exported via EXPORT_SYMBOL_GPL(). The circumvention tactic used by Nvidia was to use symbol_get() to purposely swift through proprietary module symbols and completely bypass our traditional EXPORT_SYMBOL*() annotations and community agreed upon restrictions. A small set of preamble patches fix up a few symbols which just needed adjusting for this on two modules, the rtc ds1685 and the networking enetc module. Two other modules just needed some build fixing and removal of use of __symbol_get() as they can't ever be modular, as was done by Arnd on the ARM pxa module and Christoph did on the mmc au1xmmc driver. This is a good reminder to us that symbol_get() is just a hack to address things which should be fixed through Kconfig at build time as was done in the later patches, and so ultimately it should just go. - Extremely late minor fix for old module layout 055f23b74b20 ("module: check for exit sections in layout_sections() instead of module_init_section()") by James Morse for arm64. Note that this layout thing is old, it is *not* Song Liu's commit ac3b43283923 ("module: replace module_layout with module_memory"). The issue however is very odd to run into and so there was no hurry to get this in fast. - Although the fix did not go through the modules tree I'd like to highlight the fix by Peter Zijlstra in commit 54097309620e ("x86/static_call: Fix __static_call_fixup()") now merged in your tree which came out of what was originally suspected to be a fallout of the the newer module layout changes by Song Liu commit ac3b43283923 ("module: replace module_layout with module_memory") instead of module_init_section()"). Thanks to the report by Christian Bricart and the debugging by Song Liu & Peter that turned to be noted as a kernel regression in place since v5.19 through commit ee88d363d156 ("x86,static_call: Use alternative RET encoding"). I highlight this to reflect and clarify that we haven't seen more fallout from ac3b43283923 ("module: replace module_layout with module_memory"). - RISC-V toolchain got mapping symbol support which prefix symbols with "$" to help with alignment considerations for disassembly. This is used to differentiate between incompatible instruction encodings when disassembling. RISC-V just matches what ARM/AARCH64 did for alignment considerations and Palmer Dabbelt extended is_mapping_symbol() to accept these symbols for RISC-V. We already had support for this for all architectures but it also checked for the second character, the RISC-V check Dabbelt added was just for the "$". After a bit of testing and fallout on linux-next and based on feedback from Masahiro Yamada it was decided to simplify the check and treat the first char "$" as unique for all architectures, and so we no make is_mapping_symbol() for all archs if the symbol starts with "$". The most relevant commit for this for RISC-V on binutils was: https://sourceware.org/pipermail/binutils/2021-July/117350.html - A late fix by Andrea Righi (today) to make module zstd decompression use vmalloc() instead of kmalloc() to account for large compressed modules. I suspect we'll see similar things for other decompression algorithms soon. - samples/hw_breakpoint minor fixes by Rong Tao, Arnd Bergmann and Chen Jiahao" * tag 'modules-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: module/decompress: use vmalloc() for zstd decompression workspace kallsyms: Add more debug output for selftest ARM: module: Use module_init_layout_section() to spot init sections arm64: module: Use module_init_layout_section() to spot init sections module: Expose module_init_layout_section() modules: only allow symbol_get of EXPORT_SYMBOL_GPL modules rtc: ds1685: use EXPORT_SYMBOL_GPL for ds1685_rtc_poweroff net: enetc: use EXPORT_SYMBOL_GPL for enetc_phc_index mmc: au1xmmc: force non-modular build and remove symbol_get usage ARM: pxa: remove use of symbol_get() samples/hw_breakpoint: mark sample_hbp as static samples/hw_breakpoint: fix building without module unloading samples/hw_breakpoint: Fix kernel BUG 'invalid opcode: 0000' modpost, kallsyms: Treat add '$'-prefixed symbols as mapping symbols kernel: params: Remove unnecessary ‘0’ values from err module: Ignore RISC-V mapping symbols too
| * kallsyms: Add more debug output for selftestKees Cook2023-08-241-4/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While debugging a recent kallsyms_selftest failure[1], I needed more details on what specifically was failing. This adds those details for each failure state that is checked. [1] https://lore.kernel.org/all/202308232200.1c932a90-oliver.sang@intel.com/ Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Yonghong Song <yhs@meta.com> Cc: "Erhard F." <erhard_f@mailbox.org> Cc: Zhen Lei <thunder.leizhen@huawei.com> Cc: kernel test robot <oliver.sang@intel.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
* | kallsyms: Fix kallsyms_selftest failureYonghong Song2023-08-251-22/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kernel test robot reported a kallsyms_test failure when clang lto is enabled (thin or full) and CONFIG_KALLSYMS_SELFTEST is also enabled. I can reproduce in my local environment with the following error message with thin lto: [ 1.877897] kallsyms_selftest: Test for 1750th symbol failed: (tsc_cs_mark_unstable) addr=ffffffff81038090 [ 1.877901] kallsyms_selftest: abort It appears that commit 8cc32a9bbf29 ("kallsyms: strip LTO-only suffixes from promoted global functions") caused the failure. Commit 8cc32a9bbf29 changed cleanup_symbol_name() based on ".llvm." instead of '.' where ".llvm." is appended to a before-lto-optimization local symbol name. We need to propagate such knowledge in kallsyms_selftest.c as well. Further more, compare_symbol_name() in kallsyms.c needs change as well. In scripts/kallsyms.c, kallsyms_names and kallsyms_seqs_of_names are used to record symbol names themselves and index to symbol names respectively. For example: kallsyms_names: ... __amd_smn_rw._entry <== seq 1000 __amd_smn_rw._entry.5 <== seq 1001 __amd_smn_rw.llvm.<hash> <== seq 1002 ... kallsyms_seqs_of_names are sorted based on cleanup_symbol_name() through, so the order in kallsyms_seqs_of_names actually has index 1000: seq 1002 <== __amd_smn_rw.llvm.<hash> (actual symbol comparison using '__amd_smn_rw') index 1001: seq 1000 <== __amd_smn_rw._entry index 1002: seq 1001 <== __amd_smn_rw._entry.5 Let us say at a particular point, at index 1000, symbol '__amd_smn_rw.llvm.<hash>' is comparing to '__amd_smn_rw._entry' where '__amd_smn_rw._entry' is the one to search e.g., with function kallsyms_on_each_match_symbol(). The current implementation will find out '__amd_smn_rw._entry' is less than '__amd_smn_rw.llvm.<hash>' and then continue to search e.g., index 999 and never found a match although the actual index 1001 is a match. To fix this issue, let us do cleanup_symbol_name() first and then do comparison. In the above case, comparing '__amd_smn_rw' vs '__amd_smn_rw._entry' and '__amd_smn_rw._entry' being greater than '__amd_smn_rw', the next comparison will be > index 1000 and eventually index 1001 will be hit an a match is found. For any symbols not having '.llvm.' substr, there is no functionality change for compare_symbol_name(). Fixes: 8cc32a9bbf29 ("kallsyms: strip LTO-only suffixes from promoted global functions") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202308232200.1c932a90-oliver.sang@intel.com Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Reviewed-by: Song Liu <song@kernel.org> Reviewed-by: Zhen Lei <thunder.leizhen@huawei.com> Link: https://lore.kernel.org/r/20230825034659.1037627-1-yonghong.song@linux.dev Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
* kallsyms: Delete an unused parameter related to ↵Zhen Lei2023-03-191-3/+3
| | | | | | | | | | | | | | {module_}kallsyms_on_each_symbol() The parameter 'struct module *' in the hook function associated with {module_}kallsyms_on_each_symbol() is no longer used. Delete it. Suggested-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
* kallsyms: Fix scheduling with interrupts disabled in self-testNicholas Piggin2023-01-131-15/+6
| | | | | | | | | | | | | | | | kallsyms_on_each* may schedule so must not be called with interrupts disabled. The iteration function could disable interrupts, but this also changes lookup_symbol() to match the change to the other timing code. Reported-by: Erhard F. <erhard_f@mailbox.org> Link: https://lore.kernel.org/all/bug-216902-206035@https.bugzilla.kernel.org%2F/ Reported-by: kernel test robot <oliver.sang@intel.com> Link: https://lore.kernel.org/oe-lkp/202212251728.8d0872ff-oliver.sang@intel.com Fixes: 30f3bb09778d ("kallsyms: Add self-test facility") Tested-by: "Erhard F." <erhard_f@mailbox.org> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
* kallsyms: Remove unneeded semicolonYang Li2022-11-181-1/+1
| | | | | | | | | ./kernel/kallsyms_selftest.c:136:2-3: Unneeded semicolon Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=3208 Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
* kallsyms: Add self-test facilityZhen Lei2022-11-151-0/+485
Added test cases for basic functions and performance of functions kallsyms_lookup_name(), kallsyms_on_each_symbol() and kallsyms_on_each_match_symbol(). It also calculates the compression rate of the kallsyms compression algorithm for the current symbol set. The basic functions test begins by testing a set of symbols whose address values are known. Then, traverse all symbol addresses and find the corresponding symbol name based on the address. It's impossible to determine whether these addresses are correct, but we can use the above three functions along with the addresses to test each other. Due to the traversal operation of kallsyms_on_each_symbol() is too slow, only 60 symbols can be tested in one second, so let it test on average once every 128 symbols. The other two functions validate all symbols. If the basic functions test is passed, print only performance test results. If the test fails, print error information, but do not perform subsequent performance tests. Start self-test automatically after system startup if CONFIG_KALLSYMS_SELFTEST=y. Example of output content: (prefix 'kallsyms_selftest:' is omitted start --------------------------------------------------------- | nr_symbols | compressed size | original size | ratio(%) | |---------------------------------------------------------| | 107543 | 1357912 | 2407433 | 56.40 | --------------------------------------------------------- kallsyms_lookup_name() looked up 107543 symbols The time spent on each symbol is (ns): min=630, max=35295, avg=7353 kallsyms_on_each_symbol() traverse all: 11782628 ns kallsyms_on_each_match_symbol() traverse all: 9261 ns finish Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>