From 83fb49389bbe07defb85b063f7ff0fd016f06b35 Mon Sep 17 00:00:00 2001 From: Alexey Gladkov Date: Thu, 18 Sep 2025 10:05:50 +0200 Subject: modpost: Add modname to mod_device_table alias At this point, if a symbol is compiled as part of the kernel, information about which module the symbol belongs to is lost. To save this it is possible to add the module name to the alias name. It's not very pretty, but it's possible for now. Cc: Miguel Ojeda Cc: Andreas Hindborg Cc: Danilo Krummrich Cc: Alex Gaynor Cc: rust-for-linux@vger.kernel.org Signed-off-by: Alexey Gladkov Acked-by: Danilo Krummrich Acked-by: Nicolas Schier Link: https://patch.msgid.link/1a0d0bd87a4981d465b9ed21e14f4e78eaa03ded.1758182101.git.legion@kernel.org Signed-off-by: Nathan Chancellor --- scripts/mod/file2alias.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'scripts/mod/file2alias.c') diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index 00586119a25b..1260bc2287fb 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -1476,7 +1476,7 @@ void handle_moddevtable(struct module *mod, struct elf_info *info, { void *symval; char *zeros = NULL; - const char *type, *name; + const char *type, *name, *modname; size_t typelen; static const char *prefix = "__mod_device_table__"; @@ -1488,10 +1488,19 @@ void handle_moddevtable(struct module *mod, struct elf_info *info, if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT) return; - /* All our symbols are of form __mod_device_table____. */ + /* All our symbols are of form __mod_device_table__kmod_____. */ if (!strstarts(symname, prefix)) return; - type = symname + strlen(prefix); + + modname = strstr(symname, "__kmod_"); + if (!modname) + return; + modname += strlen("__kmod_"); + + type = strstr(modname, "__"); + if (!type) + return; + type += strlen("__"); name = strstr(type, "__"); if (!name) -- cgit From 5ab23c7923a1d2ae1890026866a2d8506b010a4a Mon Sep 17 00:00:00 2001 From: Alexey Gladkov Date: Thu, 18 Sep 2025 10:05:51 +0200 Subject: modpost: Create modalias for builtin modules For some modules, modalias is generated using the modpost utility and the section is added to the module file. When a module is added inside vmlinux, modpost does not generate modalias for such modules and the information is lost. As a result kmod (which uses modules.builtin.modinfo in userspace) cannot determine that modalias is handled by a builtin kernel module. $ cat /sys/devices/pci0000:00/0000:00:14.0/modalias pci:v00008086d0000A36Dsv00001043sd00008694bc0Csc03i30 $ modinfo xhci_pci name: xhci_pci filename: (builtin) license: GPL file: drivers/usb/host/xhci-pci description: xHCI PCI Host Controller Driver Missing modalias "pci:v*d*sv*sd*bc0Csc03i30*" which will be generated by modpost if the module is built separately. To fix this it is necessary to generate the same modalias for vmlinux as for the individual modules. Fortunately '.vmlinux.export.o' is already generated from which '.modinfo' can be extracted in the same way as for vmlinux.o. Signed-off-by: Masahiro Yamada Signed-off-by: Alexey Gladkov Tested-by: Stephen Rothwell Reviewed-by: Nicolas Schier Link: https://patch.msgid.link/28d4da3b0e3fc8474142746bcf469e03752c3208.1758182101.git.legion@kernel.org Signed-off-by: Nathan Chancellor --- scripts/mod/file2alias.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) (limited to 'scripts/mod/file2alias.c') diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index 1260bc2287fb..7da9735e7ab3 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -1477,7 +1477,7 @@ void handle_moddevtable(struct module *mod, struct elf_info *info, void *symval; char *zeros = NULL; const char *type, *name, *modname; - size_t typelen; + size_t typelen, modnamelen; static const char *prefix = "__mod_device_table__"; /* We're looking for a section relative symbol */ @@ -1500,6 +1500,7 @@ void handle_moddevtable(struct module *mod, struct elf_info *info, type = strstr(modname, "__"); if (!type) return; + modnamelen = type - modname; type += strlen("__"); name = strstr(type, "__"); @@ -1526,5 +1527,21 @@ void handle_moddevtable(struct module *mod, struct elf_info *info, } } + if (mod->is_vmlinux) { + struct module_alias *alias; + + /* + * If this is vmlinux, record the name of the builtin module. + * Traverse the linked list in the reverse order, and set the + * builtin_modname unless it has already been set in the + * previous call. + */ + list_for_each_entry_reverse(alias, &mod->aliases, node) { + if (alias->builtin_modname) + break; + alias->builtin_modname = xstrndup(modname, modnamelen); + } + } + free(zeros); } -- cgit