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charset=UTF-8 Content-Transfer-Encoding: 7bit On 11/23/24 03:42, Matthew Maurer wrote: > Document where exported and imported symbols are kept, format options, > and limitations. > > Signed-off-by: Matthew Maurer > --- > Documentation/kbuild/modules.rst | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/Documentation/kbuild/modules.rst b/Documentation/kbuild/modules.rst > index 101de236cd0c9abe1f5684d80063ff3f9a7fc673..c32e3ed67cd26070f6929f6ad98c4308a1ab71f8 100644 > --- a/Documentation/kbuild/modules.rst > +++ b/Documentation/kbuild/modules.rst > @@ -423,6 +423,26 @@ Symbols From the Kernel (vmlinux + modules) > 1) It lists all exported symbols from vmlinux and all modules. > 2) It lists the CRC if CONFIG_MODVERSIONS is enabled. > > +Version Information Formats > +--------------------------- > + > + Exported symbols have information stored in __ksymtab or __ksymtab_gpl > + sections. Symbol names and namespaces are stored in __kstrtab and > + __kstrtabns respectively, using a format similar to the string table > + used for ELF. If CONFIG_MODVERSIONS is enabled, the CRCs corresponding > + to exported symbols will be added to the __kcrctab or __kcrctab_gpl. The second sentence should be that symbol names and namespaces of exported symbols are both stored in the __ksymtab_strings section. > + > + If CONFIG_BASIC_MODVERSIONS is enabled (default with > + CONFIG_MODVERSIONS), imported symbols will have their symbol name and > + CRC stored in the __versions section of the importing module. This > + mode only supports symbols of length up to 64 bytes. > + > + If CONFIG_EXTENDED_MODVERSIONS is enabled (required to enable both > + CONFIG_MODVERSIONS and CONFIG_RUST at the same time), imported symbols > + will have their symbol name recorded in the __version_ext_names > + section as a series of concatenated, null-terminated strings. CRCs for > + these symbols will be recorded in the __version_ext_crcs section. > + > Symbols and External Modules > ---------------------------- > > -- Thanks, Petr