modpost, kallsyms: Treat add '$'-prefixed symbols as mapping symbols

Trying to restrict the '$'-prefix change to RISC-V caused some fallout,
so let's just treat all those symbols as special.

Fixes: c05780ef3c ("module: Ignore RISC-V mapping symbols too")
Link: https://lore.kernel.org/all/20230712015747.77263-1-wangkefeng.wang@huawei.com/
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
This commit is contained in:
Palmer Dabbelt 2023-07-21 08:01:48 -07:00 committed by Luis Chamberlain
parent 9ce170cef6
commit ff09f6fd29
3 changed files with 4 additions and 16 deletions

View File

@ -3,25 +3,13 @@
#define _LINUX_MODULE_SYMBOL_H
/* This ignores the intensely annoying "mapping symbols" found in ELF files. */
static inline int is_mapping_symbol(const char *str, int is_riscv)
static inline int is_mapping_symbol(const char *str)
{
if (str[0] == '.' && str[1] == 'L')
return true;
if (str[0] == 'L' && str[1] == '0')
return true;
/*
* RISC-V defines various special symbols that start with "$".  The
* mapping symbols, which exist to differentiate between incompatible
* instruction encodings when disassembling, show up all over the place
* and are generally not meant to be treated like other symbols.  So
* just ignore any of the special symbols.
*/
if (is_riscv)
return str[0] == '$';
return str[0] == '$' &&
(str[1] == 'a' || str[1] == 'd' || str[1] == 't' || str[1] == 'x')
&& (str[2] == '\0' || str[2] == '.');
return str[0] == '$';
}
#endif /* _LINUX_MODULE_SYMBOL_H */

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@ -289,7 +289,7 @@ static const char *find_kallsyms_symbol(struct module *mod,
* and inserted at a whim.
*/
if (*kallsyms_symbol_name(kallsyms, i) == '\0' ||
is_mapping_symbol(kallsyms_symbol_name(kallsyms, i), IS_ENABLED(CONFIG_RISCV)))
is_mapping_symbol(kallsyms_symbol_name(kallsyms, i)))
continue;
if (thisval <= addr && thisval > bestval) {

View File

@ -1052,7 +1052,7 @@ static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
if (!name || !strlen(name))
return 0;
return !is_mapping_symbol(name, elf->hdr->e_machine == EM_RISCV);
return !is_mapping_symbol(name);
}
/* Look up the nearest symbol based on the section and the address */