diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Kconfig.debug | 135 | ||||
| -rw-r--r-- | lib/Makefile | 1 | ||||
| -rw-r--r-- | lib/devres.c | 6 | ||||
| -rw-r--r-- | lib/string.c | 23 | ||||
| -rw-r--r-- | lib/tests/Makefile | 1 | ||||
| -rw-r--r-- | lib/tests/module/.gitignore | 4 | ||||
| -rw-r--r-- | lib/tests/module/Makefile | 14 | ||||
| -rwxr-xr-x | lib/tests/module/gen_test_kallsyms.sh | 134 |
8 files changed, 308 insertions, 10 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 1e37c62e8595..f3d723705879 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -2920,6 +2920,141 @@ config TEST_KMOD If unsure, say N. +config TEST_RUNTIME + bool + +config TEST_RUNTIME_MODULE + bool + +config TEST_KALLSYMS + tristate "module kallsyms find_symbol() test" + depends on m + select TEST_RUNTIME + select TEST_RUNTIME_MODULE + select TEST_KALLSYMS_A + select TEST_KALLSYMS_B + select TEST_KALLSYMS_C + select TEST_KALLSYMS_D + help + This allows us to stress test find_symbol() through the kallsyms + used to place symbols on the kernel ELF kallsyms and modules kallsyms + where we place kernel symbols such as exported symbols. + + We have four test modules: + + A: has KALLSYSMS_NUMSYMS exported symbols + B: uses one of A's symbols + C: adds KALLSYMS_SCALE_FACTOR * KALLSYSMS_NUMSYMS exported + D: adds 2 * the symbols than C + + We stress test find_symbol() through two means: + + 1) Upon load of B it will trigger simplify_symbols() to look for the + one symbol it uses from the module A with tons of symbols. This is an + indirect way for us to have B call resolve_symbol_wait() upon module + load. This will eventually call find_symbol() which will eventually + try to find the symbols used with find_exported_symbol_in_section(). + find_exported_symbol_in_section() uses bsearch() so a binary search + for each symbol. Binary search will at worst be O(log(n)) so the + larger TEST_MODULE_KALLSYSMS the worse the search. + + 2) The selftests should load C first, before B. Upon B's load towards + the end right before we call module B's init routine we get + complete_formation() called on the module. That will first check + for duplicate symbols with the call to verify_exported_symbols(). + That is when we'll force iteration on module C's insane symbol list. + Since it has 10 * KALLSYMS_NUMSYMS it means we can first test + just loading B without C. The amount of time it takes to load C Vs + B can give us an idea of the impact growth of the symbol space and + give us projection. Module A only uses one symbol from B so to allow + this scaling in module C to be proportional, if it used more symbols + then the first test would be doing more and increasing just the + search space would be slightly different. The last module, module D + will just increase the search space by twice the number of symbols in + C so to allow for full projects. + + tools/testing/selftests/module/find_symbol.sh + + The current defaults will incur a build delay of about 7 minutes + on an x86_64 with only 8 cores. Enable this only if you want to + stress test find_symbol() with thousands of symbols. At the same + time this is also useful to test building modules with thousands of + symbols, and if BTF is enabled this also stress tests adding BTF + information for each module. Currently enabling many more symbols + will segfault the build system. + + If unsure, say N. + +if TEST_KALLSYMS + +config TEST_KALLSYMS_A + tristate + depends on m + +config TEST_KALLSYMS_B + tristate + depends on m + +config TEST_KALLSYMS_C + tristate + depends on m + +config TEST_KALLSYMS_D + tristate + depends on m + +choice + prompt "Kallsym test range" + default TEST_KALLSYMS_LARGE + help + Selecting something other than "Fast" will enable tests which slow + down the build and may crash your build. + +config TEST_KALLSYMS_FAST + bool "Fast builds" + help + You won't really be testing kallsysms, so this just helps fast builds + when allmodconfig is used.. + +config TEST_KALLSYMS_LARGE + bool "Enable testing kallsyms with large exports" + help + This will enable larger number of symbols. This will slow down + your build considerably. + +config TEST_KALLSYMS_MAX + bool "Known kallsysms limits" + help + This will enable exports to the point we know we'll start crashing + builds. + +endchoice + +config TEST_KALLSYMS_NUMSYMS + int "test kallsyms number of symbols" + range 2 10000 + default 2 if TEST_KALLSYMS_FAST + default 100 if TEST_KALLSYMS_LARGE + default 10000 if TEST_KALLSYMS_MAX + help + The number of symbols to create on TEST_KALLSYMS_A, only one of which + module TEST_KALLSYMS_B will use. This also will be used + for how many symbols TEST_KALLSYMS_C will have, scaled up by + TEST_KALLSYMS_SCALE_FACTOR. Note that setting this to 10,000 will + trigger a segfault today, don't use anything close to it unless + you are aware that this should not be used for automated build tests. + +config TEST_KALLSYMS_SCALE_FACTOR + int "test kallsyms scale factor" + default 8 + help + How many more unusued symbols will TEST_KALLSYSMS_C have than + TEST_KALLSYMS_A. If 8, then module C will have 8 * syms + than module A. Then TEST_KALLSYMS_D will have double the amount + of symbols than C so to allow projections. + +endif # TEST_KALLSYMS + config TEST_DEBUG_VIRTUAL tristate "Test CONFIG_DEBUG_VIRTUAL feature" depends on DEBUG_VIRTUAL diff --git a/lib/Makefile b/lib/Makefile index 8000f2270462..a8155c972f02 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -98,6 +98,7 @@ obj-$(CONFIG_TEST_XARRAY) += test_xarray.o obj-$(CONFIG_TEST_MAPLE_TREE) += test_maple_tree.o obj-$(CONFIG_TEST_PARMAN) += test_parman.o obj-$(CONFIG_TEST_KMOD) += test_kmod.o +obj-$(CONFIG_TEST_RUNTIME) += tests/ obj-$(CONFIG_TEST_DEBUG_VIRTUAL) += test_debug_virtual.o obj-$(CONFIG_TEST_MEMCAT_P) += test_memcat_p.o obj-$(CONFIG_TEST_OBJAGG) += test_objagg.o diff --git a/lib/devres.c b/lib/devres.c index 4fc152de6d8b..73901160197e 100644 --- a/lib/devres.c +++ b/lib/devres.c @@ -115,9 +115,8 @@ EXPORT_SYMBOL(devm_ioremap_wc); */ void devm_iounmap(struct device *dev, void __iomem *addr) { - WARN_ON(devres_destroy(dev, devm_ioremap_release, devm_ioremap_match, + WARN_ON(devres_release(dev, devm_ioremap_release, devm_ioremap_match, (__force void *)addr)); - iounmap(addr); } EXPORT_SYMBOL(devm_iounmap); @@ -308,8 +307,7 @@ EXPORT_SYMBOL(devm_ioport_map); */ void devm_ioport_unmap(struct device *dev, void __iomem *addr) { - ioport_unmap(addr); - WARN_ON(devres_destroy(dev, devm_ioport_map_release, + WARN_ON(devres_release(dev, devm_ioport_map_release, devm_ioport_map_match, (__force void *)addr)); } EXPORT_SYMBOL(devm_ioport_unmap); diff --git a/lib/string.c b/lib/string.c index 76327b51e36f..eb4486ed40d2 100644 --- a/lib/string.c +++ b/lib/string.c @@ -104,6 +104,12 @@ char *strncpy(char *dest, const char *src, size_t count) EXPORT_SYMBOL(strncpy); #endif +#ifdef __BIG_ENDIAN +# define ALLBUTLAST_BYTE_MASK (~255ul) +#else +# define ALLBUTLAST_BYTE_MASK (~0ul >> 8) +#endif + ssize_t sized_strscpy(char *dest, const char *src, size_t count) { const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS; @@ -147,13 +153,18 @@ ssize_t sized_strscpy(char *dest, const char *src, size_t count) *(unsigned long *)(dest+res) = c & zero_bytemask(data); return res + find_zero(data); } + count -= sizeof(unsigned long); + if (unlikely(!count)) { + c &= ALLBUTLAST_BYTE_MASK; + *(unsigned long *)(dest+res) = c; + return -E2BIG; + } *(unsigned long *)(dest+res) = c; res += sizeof(unsigned long); - count -= sizeof(unsigned long); max -= sizeof(unsigned long); } - while (count) { + while (count > 1) { char c; c = src[res]; @@ -164,11 +175,11 @@ ssize_t sized_strscpy(char *dest, const char *src, size_t count) count--; } - /* Hit buffer length without finding a NUL; force NUL-termination. */ - if (res) - dest[res-1] = '\0'; + /* Force NUL-termination. */ + dest[res] = '\0'; - return -E2BIG; + /* Return E2BIG if the source didn't stop */ + return src[res] ? -E2BIG : res; } EXPORT_SYMBOL(sized_strscpy); diff --git a/lib/tests/Makefile b/lib/tests/Makefile new file mode 100644 index 000000000000..8e4f42cb9c54 --- /dev/null +++ b/lib/tests/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_TEST_RUNTIME_MODULE) += module/ diff --git a/lib/tests/module/.gitignore b/lib/tests/module/.gitignore new file mode 100644 index 000000000000..8be7891b250f --- /dev/null +++ b/lib/tests/module/.gitignore @@ -0,0 +1,4 @@ +test_kallsyms_a.c +test_kallsyms_b.c +test_kallsyms_c.c +test_kallsyms_d.c diff --git a/lib/tests/module/Makefile b/lib/tests/module/Makefile new file mode 100644 index 000000000000..2f3e1a772c2c --- /dev/null +++ b/lib/tests/module/Makefile @@ -0,0 +1,14 @@ +obj-$(CONFIG_TEST_KALLSYMS_A) += test_kallsyms_a.o +obj-$(CONFIG_TEST_KALLSYMS_B) += test_kallsyms_b.o +obj-$(CONFIG_TEST_KALLSYMS_C) += test_kallsyms_c.o +obj-$(CONFIG_TEST_KALLSYMS_D) += test_kallsyms_d.o + +quiet_cmd_gen_test_kallsyms = GEN $@ + cmd_gen_test_kallsyms = $< $@ \ + $(CONFIG_TEST_KALLSYMS_NUMSYMS) \ + $(CONFIG_TEST_KALLSYMS_SCALE_FACTOR) + +$(obj)/%.c: $(src)/gen_test_kallsyms.sh FORCE + $(call if_changed,gen_test_kallsyms) + +targets += $(foreach x, a b c d, test_kallsyms_$(x).c) diff --git a/lib/tests/module/gen_test_kallsyms.sh b/lib/tests/module/gen_test_kallsyms.sh new file mode 100755 index 000000000000..561dcac0f359 --- /dev/null +++ b/lib/tests/module/gen_test_kallsyms.sh @@ -0,0 +1,134 @@ +#!/bin/bash + +TARGET=$(basename $1) +DIR=lib/tests/module +TARGET="$DIR/$TARGET" +NUM_SYMS=$2 +SCALE_FACTOR=$3 +TEST_TYPE=$(echo $TARGET | sed -e 's|lib/tests/module/test_kallsyms_||g') +TEST_TYPE=$(echo $TEST_TYPE | sed -e 's|.c||g') +FIRST_B_LOOKUP=1 + +if [[ $NUM_SYMS -gt 2 ]]; then + FIRST_B_LOOKUP=$((NUM_SYMS/2)) +fi + +gen_template_module_header() +{ + cat <<____END_MODULE +// SPDX-License-Identifier: GPL-2.0-or-later OR copyleft-next-0.3.1 +/* + * Copyright (C) 2023 Luis Chamberlain <mcgrof@kernel.org> + * + * Automatically generated code for testing, do not edit manually. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/printk.h> + +____END_MODULE +} + +gen_num_syms() +{ + PREFIX=$1 + NUM=$2 + for i in $(seq 1 $NUM); do + printf "int auto_test_%s_%010d = 0;\n" $PREFIX $i + printf "EXPORT_SYMBOL_GPL(auto_test_%s_%010d);\n" $PREFIX $i + done + echo +} + +gen_template_module_data_a() +{ + gen_num_syms a $1 + cat <<____END_MODULE +static int auto_runtime_test(void) +{ + return 0; +} + +____END_MODULE +} + +gen_template_module_data_b() +{ + printf "\nextern int auto_test_a_%010d;\n\n" $FIRST_B_LOOKUP + echo "static int auto_runtime_test(void)" + echo "{" + printf "\nreturn auto_test_a_%010d;\n" $FIRST_B_LOOKUP + echo "}" +} + +gen_template_module_data_c() +{ + gen_num_syms c $1 + cat <<____END_MODULE +static int auto_runtime_test(void) +{ + return 0; +} + +____END_MODULE +} + +gen_template_module_data_d() +{ + gen_num_syms d $1 + cat <<____END_MODULE +static int auto_runtime_test(void) +{ + return 0; +} + +____END_MODULE +} + +gen_template_module_exit() +{ + cat <<____END_MODULE +static int __init auto_test_module_init(void) +{ + return auto_runtime_test(); +} +module_init(auto_test_module_init); + +static void __exit auto_test_module_exit(void) +{ +} +module_exit(auto_test_module_exit); + +MODULE_AUTHOR("Luis Chamberlain <mcgrof@kernel.org>"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Test module for kallsyms"); +____END_MODULE +} + +case $TEST_TYPE in + a) + gen_template_module_header > $TARGET + gen_template_module_data_a $NUM_SYMS >> $TARGET + gen_template_module_exit >> $TARGET + ;; + b) + gen_template_module_header > $TARGET + gen_template_module_data_b >> $TARGET + gen_template_module_exit >> $TARGET + ;; + c) + gen_template_module_header > $TARGET + gen_template_module_data_c $((NUM_SYMS * SCALE_FACTOR)) >> $TARGET + gen_template_module_exit >> $TARGET + ;; + d) + gen_template_module_header > $TARGET + gen_template_module_data_d $((NUM_SYMS * SCALE_FACTOR * 2)) >> $TARGET + gen_template_module_exit >> $TARGET + ;; + *) + ;; +esac |