[PATCH 02/17] kallsyms: increase maximum kernel symbol length to 512
From: ojeda@kernel.org
Date: 2021-07-04 20:28:43
Also in:
linux-kbuild, lkml, rust-for-linux
Subsystem:
live patching, performance events subsystem, the rest · Maintainers:
Josh Poimboeuf, Jiri Kosina, Miroslav Benes, Petr Mladek, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds
From: Miguel Ojeda <ojeda@kernel.org>
Rust symbols can become quite long due to namespacing introduced
by modules, types, traits, generics, etc. For instance, for:
pub mod my_module {
pub struct MyType;
pub struct MyGenericType<T>(T);
pub trait MyTrait {
fn my_method() -> u32;
}
impl MyTrait for MyGenericType<MyType> {
fn my_method() -> u32 {
42
}
}
}
generates a symbol of length 96 when using the upcoming v0 mangling scheme:
_RNvXNtCshGpAVYOtgW1_7example9my_moduleINtB2_13MyGenericTypeNtB2_6MyTypeENtB2_7MyTrait9my_method
At the moment, Rust symbols may reach up to 300 in length.
Setting 512 as the maximum seems like a reasonable choice to
keep some headroom.
Co-developed-by: Alex Gaynor <redacted>
Signed-off-by: Alex Gaynor <redacted>
Co-developed-by: Geoffrey Thomas <redacted>
Signed-off-by: Geoffrey Thomas <redacted>
Co-developed-by: Finn Behrens <redacted>
Signed-off-by: Finn Behrens <redacted>
Co-developed-by: Adam Bratschi-Kaye <redacted>
Signed-off-by: Adam Bratschi-Kaye <redacted>
Co-developed-by: Wedson Almeida Filho <redacted>
Signed-off-by: Wedson Almeida Filho <redacted>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
include/linux/kallsyms.h | 2 +-
kernel/livepatch/core.c | 4 ++--
scripts/kallsyms.c | 2 +-
tools/include/linux/kallsyms.h | 2 +-
tools/include/linux/lockdep.h | 2 +-
tools/lib/perf/include/perf/event.h | 2 +-
tools/lib/symbol/kallsyms.h | 2 +-
7 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h
index 465060acc98..5cdc6903abc 100644
--- a/include/linux/kallsyms.h
+++ b/include/linux/kallsyms.h@@ -14,7 +14,7 @@ #include <asm/sections.h> -#define KSYM_NAME_LEN 128 +#define KSYM_NAME_LEN 512 #define KSYM_SYMBOL_LEN (sizeof("%s+%#lx/%#lx [%s]") + (KSYM_NAME_LEN - 1) + \ 2*(BITS_PER_LONG*3/10) + (MODULE_NAME_LEN - 1) + 1)
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index 335d988bd81..73874e5edfd 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c@@ -213,7 +213,7 @@ static int klp_resolve_symbols(Elf64_Shdr *sechdrs, const char *strtab, * we use the smallest/strictest upper bound possible (56, based on * the current definition of MODULE_NAME_LEN) to prevent overflows. */ - BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 128); + BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 512); relas = (Elf_Rela *) relasec->sh_addr; /* For each rela in this klp relocation section */
@@ -227,7 +227,7 @@ static int klp_resolve_symbols(Elf64_Shdr *sechdrs, const char *strtab, /* Format: .klp.sym.sym_objname.sym_name,sympos */ cnt = sscanf(strtab + sym->st_name, - ".klp.sym.%55[^.].%127[^,],%lu", + ".klp.sym.%55[^.].%511[^,],%lu", sym_objname, sym_name, &sympos); if (cnt != 3) { pr_err("symbol %s has an incorrectly formatted name\n",
diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c
index bcdabee13aa..9bab5f55ade 100644
--- a/scripts/kallsyms.c
+++ b/scripts/kallsyms.c@@ -27,7 +27,7 @@ #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0])) -#define KSYM_NAME_LEN 128 +#define KSYM_NAME_LEN 512 struct sym_entry { unsigned long long addr;
diff --git a/tools/include/linux/kallsyms.h b/tools/include/linux/kallsyms.h
index efb6c3f5f2a..5a37ccbec54 100644
--- a/tools/include/linux/kallsyms.h
+++ b/tools/include/linux/kallsyms.h@@ -6,7 +6,7 @@ #include <stdio.h> #include <unistd.h> -#define KSYM_NAME_LEN 128 +#define KSYM_NAME_LEN 512 struct module;
diff --git a/tools/include/linux/lockdep.h b/tools/include/linux/lockdep.h
index e56997288f2..d9c163f3ab2 100644
--- a/tools/include/linux/lockdep.h
+++ b/tools/include/linux/lockdep.h@@ -47,7 +47,7 @@ static inline int debug_locks_off(void) #define task_pid_nr(tsk) ((tsk)->pid) -#define KSYM_NAME_LEN 128 +#define KSYM_NAME_LEN 512 #define printk(...) dprintf(STDOUT_FILENO, __VA_ARGS__) #define pr_err(format, ...) fprintf (stderr, format, ## __VA_ARGS__) #define pr_warn pr_err
diff --git a/tools/lib/perf/include/perf/event.h b/tools/lib/perf/include/perf/event.h
index 4d0c02ba3f7..095d60144a7 100644
--- a/tools/lib/perf/include/perf/event.h
+++ b/tools/lib/perf/include/perf/event.h@@ -95,7 +95,7 @@ struct perf_record_throttle { }; #ifndef KSYM_NAME_LEN -#define KSYM_NAME_LEN 256 +#define KSYM_NAME_LEN 512 #endif struct perf_record_ksymbol {
diff --git a/tools/lib/symbol/kallsyms.h b/tools/lib/symbol/kallsyms.h
index 72ab9870454..542f9b059c3 100644
--- a/tools/lib/symbol/kallsyms.h
+++ b/tools/lib/symbol/kallsyms.h@@ -7,7 +7,7 @@ #include <linux/types.h> #ifndef KSYM_NAME_LEN -#define KSYM_NAME_LEN 256 +#define KSYM_NAME_LEN 512 #endif static inline u8 kallsyms2elf_binding(char type)
--
2.32.0