* [PATCH v2 1/2] module: expose imported namespaces via sysfs
2026-03-07 9:00 [PATCH v2 0/2] module: expose imported namespaces via sysfs Nicholas Sielicki
@ 2026-03-07 9:00 ` Nicholas Sielicki
2026-03-07 9:30 ` Peter Zijlstra
2026-03-07 9:00 ` [PATCH v2 2/2] docs: symbol-namespaces: mention sysfs attribute Nicholas Sielicki
2026-03-20 17:45 ` [PATCH v2 0/2] module: expose imported namespaces via sysfs Sami Tolvanen
2 siblings, 1 reply; 6+ messages in thread
From: Nicholas Sielicki @ 2026-03-07 9:00 UTC (permalink / raw)
To: Luis Chamberlain, Petr Pavlu, Daniel Gomez
Cc: Sami Tolvanen, Aaron Tomlin, Matthias Maennich, Peter Zijlstra,
Jonathan Corbet, Shuah Khan, Randy Dunlap, linux-modules,
linux-doc, linux-kernel, Nicholas Sielicki
Previously, the only way for userspace to inspect the symbol
namespaces a module imports is to locate the .ko on disk and invoke
modinfo(8) to decompress/parse the metadata. The kernel validated
namespaces at load time, but it was otherwise discarded.
Add /sys/module/*/import_ns to expose imported namespaces for
currently loaded modules. The file contains one namespace per line and
only exists for modules that import at least one namespace.
Signed-off-by: Nicholas Sielicki <linux@opensource.nslick.com>
---
Documentation/ABI/testing/sysfs-module | 9 ++++
include/linux/module.h | 1 +
kernel/module/main.c | 69 +++++++++++++++++++++++++-
3 files changed, 78 insertions(+), 1 deletion(-)
diff --git a/Documentation/ABI/testing/sysfs-module b/Documentation/ABI/testing/sysfs-module
index 6bc9af6229f0..d5b7d19bd310 100644
--- a/Documentation/ABI/testing/sysfs-module
+++ b/Documentation/ABI/testing/sysfs-module
@@ -48,6 +48,15 @@ Contact: Kay Sievers <kay.sievers@vrfy.org>
Description: Show the initialization state(live, coming, going) of
the module.
+What: /sys/module/*/import_ns
+Date: January 2026
+KernelVersion: 7.1
+Contact: linux-modules@vger.kernel.org
+Description: List of symbol namespaces imported by this module via
+ MODULE_IMPORT_NS(). Each namespace appears on a separate line.
+ This file only exists for modules that import at least one
+ namespace.
+
What: /sys/module/*/taint
Date: Jan 2012
KernelVersion: 3.3
diff --git a/include/linux/module.h b/include/linux/module.h
index 14f391b186c6..60ed1c3e0ed9 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -413,6 +413,7 @@ struct module {
struct module_attribute *modinfo_attrs;
const char *version;
const char *srcversion;
+ const char *imported_namespaces;
struct kobject *holders_dir;
/* Exported symbols */
diff --git a/kernel/module/main.c b/kernel/module/main.c
index c3ce106c70af..53e421ff2ede 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -607,6 +607,36 @@ static const struct module_attribute modinfo_##field = { \
MODINFO_ATTR(version);
MODINFO_ATTR(srcversion);
+static void setup_modinfo_import_ns(struct module *mod, const char *s)
+{
+ mod->imported_namespaces = NULL;
+}
+
+static ssize_t show_modinfo_import_ns(const struct module_attribute *mattr,
+ struct module_kobject *mk, char *buffer)
+{
+ return sysfs_emit(buffer, "%s\n", mk->mod->imported_namespaces);
+}
+
+static int modinfo_import_ns_exists(struct module *mod)
+{
+ return mod->imported_namespaces != NULL;
+}
+
+static void free_modinfo_import_ns(struct module *mod)
+{
+ kfree(mod->imported_namespaces);
+ mod->imported_namespaces = NULL;
+}
+
+static const struct module_attribute modinfo_import_ns = {
+ .attr = { .name = "import_ns", .mode = 0444 },
+ .show = show_modinfo_import_ns,
+ .setup = setup_modinfo_import_ns,
+ .test = modinfo_import_ns_exists,
+ .free = free_modinfo_import_ns,
+};
+
static struct {
char name[MODULE_NAME_LEN];
char taints[MODULE_FLAGS_BUF_SIZE];
@@ -1058,6 +1088,7 @@ const struct module_attribute *const modinfo_attrs[] = {
&module_uevent,
&modinfo_version,
&modinfo_srcversion,
+ &modinfo_import_ns,
&modinfo_initstate,
&modinfo_coresize,
#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
@@ -1760,11 +1791,43 @@ static void module_license_taint_check(struct module *mod, const char *license)
}
}
+static int copy_modinfo_import_ns(struct module *mod, struct load_info *info)
+{
+ char *ns;
+ size_t len, total_len = 0;
+ char *buf, *p;
+
+ for_each_modinfo_entry(ns, info, "import_ns")
+ total_len += strlen(ns) + 1;
+
+ if (!total_len) {
+ mod->imported_namespaces = NULL;
+ return 0;
+ }
+
+ buf = kmalloc(total_len, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ p = buf;
+ for_each_modinfo_entry(ns, info, "import_ns") {
+ len = strlen(ns);
+ memcpy(p, ns, len);
+ p += len;
+ *p++ = '\n';
+ }
+ /* Replace trailing newline with null terminator. */
+ *(p - 1) = '\0';
+
+ mod->imported_namespaces = buf;
+ return 0;
+}
+
static int setup_modinfo(struct module *mod, struct load_info *info)
{
const struct module_attribute *attr;
char *imported_namespace;
- int i;
+ int i, err;
for (i = 0; (attr = modinfo_attrs[i]); i++) {
if (attr->setup)
@@ -1783,6 +1846,10 @@ static int setup_modinfo(struct module *mod, struct load_info *info)
}
}
+ err = copy_modinfo_import_ns(mod, info);
+ if (err)
+ return err;
+
return 0;
}
--
2.53.0
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v2 2/2] docs: symbol-namespaces: mention sysfs attribute
2026-03-07 9:00 [PATCH v2 0/2] module: expose imported namespaces via sysfs Nicholas Sielicki
2026-03-07 9:00 ` [PATCH v2 1/2] " Nicholas Sielicki
@ 2026-03-07 9:00 ` Nicholas Sielicki
2026-03-20 17:45 ` [PATCH v2 0/2] module: expose imported namespaces via sysfs Sami Tolvanen
2 siblings, 0 replies; 6+ messages in thread
From: Nicholas Sielicki @ 2026-03-07 9:00 UTC (permalink / raw)
To: Luis Chamberlain, Petr Pavlu, Daniel Gomez
Cc: Sami Tolvanen, Aaron Tomlin, Matthias Maennich, Peter Zijlstra,
Jonathan Corbet, Shuah Khan, Randy Dunlap, linux-modules,
linux-doc, linux-kernel, Nicholas Sielicki
Reference the new /sys/module/*/import_ns sysfs attribute in docs as an
alternative to modinfo for inspecting imported namespaces of loaded
modules.
Signed-off-by: Nicholas Sielicki <linux@opensource.nslick.com>
---
Documentation/core-api/symbol-namespaces.rst | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/Documentation/core-api/symbol-namespaces.rst b/Documentation/core-api/symbol-namespaces.rst
index 034898e81ba2..2304d5bffcce 100644
--- a/Documentation/core-api/symbol-namespaces.rst
+++ b/Documentation/core-api/symbol-namespaces.rst
@@ -114,6 +114,11 @@ inspected with modinfo::
import_ns: USB_STORAGE
[...]
+For modules that are currently loaded, imported namespaces are also available
+via sysfs::
+
+ $ cat /sys/module/ums_karma/import_ns
+ USB_STORAGE
It is advisable to add the MODULE_IMPORT_NS() statement close to other module
metadata definitions like MODULE_AUTHOR() or MODULE_LICENSE().
--
2.53.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v2 0/2] module: expose imported namespaces via sysfs
2026-03-07 9:00 [PATCH v2 0/2] module: expose imported namespaces via sysfs Nicholas Sielicki
2026-03-07 9:00 ` [PATCH v2 1/2] " Nicholas Sielicki
2026-03-07 9:00 ` [PATCH v2 2/2] docs: symbol-namespaces: mention sysfs attribute Nicholas Sielicki
@ 2026-03-20 17:45 ` Sami Tolvanen
2 siblings, 0 replies; 6+ messages in thread
From: Sami Tolvanen @ 2026-03-20 17:45 UTC (permalink / raw)
To: Luis Chamberlain, Petr Pavlu, Daniel Gomez, Nicholas Sielicki
Cc: Aaron Tomlin, Matthias Maennich, Peter Zijlstra, Jonathan Corbet,
Shuah Khan, Randy Dunlap, linux-modules, linux-doc, linux-kernel
On Sat, 07 Mar 2026 03:00:08 -0600, Nicholas Sielicki wrote:
> Add /sys/module/*/import_ns to expose the symbol namespaces imported
> by a loaded module.
>
> Changes since v1:
> - Simplified commit message to drop unnecessary/incorrect background
> - Use .setup/.free callbacks in module_attribute to ensure
> imported_namespaces is NULL-initialized before error paths and
> NULL'd after kfree (Sami)
> - Updated KernelVersion to 7.1 in docs for next merge window
>
> [...]
Applied to modules-next, thanks!
[1/2] module: expose imported namespaces via sysfs
commit: 3fe1dcbc2d20c5dbc581c0bb458e05365bfffcf7
[2/2] docs: symbol-namespaces: mention sysfs attribute
commit: f15dbe8a94b6e3768b10e10bf8ab95b28682db80
Best regards,
Sami
^ permalink raw reply [flat|nested] 6+ messages in thread