[PATCH v10 35/38] dyndbg: Ignore additional arguments from pr_fmt
From: Jim Cromie via B4 Relay <devnull+jim.cromie.gmail.com@kernel.org>
Date: 2026-09-16 15:33:03
Also in:
b4-sent, dri-devel, linux-arch, linux-doc, linux-kbuild, linux-kselftest, linux-pm, lkml
Subsystem:
dynamic debug, kernel selftest framework, library code, printk, the rest · Maintainers:
Jason Baron, Jim Cromie, Shuah Khan, Shuah Khan, Andrew Morton, Petr Mladek, Linus Torvalds
From: Philipp Hahn <redacted> pr_fmt can be used to add a common prefix to any output from a module: #define pr_fmt(fmt) KBUILD_MODNAME ".%s " fmt, __func__ But adding additional arguments breaks dynamic debug:
error: macro "DEFINE_DYNAMIC_DEBUG_METADATA_CLS" passed 4 arguments, but takes just 3
| pr_debug_ratelimited("%s", "Hello world!");
| ^
note: macro "DEFINE_DYNAMIC_DEBUG_METADATA_CLS" defined here
| #define DEFINE_DYNAMIC_DEBUG_METADATA_CLS(name, cls, fmt) \
|
error: ‘DEFINE_DYNAMIC_DEBUG_METADATA_CLS’ undeclared (first use in this function)
| DEFINE_DYNAMIC_DEBUG_METADATA_CLS(name, _DPRINTK_CLASS_DFLT, fmt)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
note: in expansion of macro ‘DEFINE_DYNAMIC_DEBUG_METADATA’
| DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, pr_fmt(fmt)); \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
note: in expansion of macro ‘pr_debug_ratelimited’
| pr_debug_ratelimited("%s", "Hello world!");
| ^~~~~~~~~~~~~~~~~~~~Add an additional ', ...' to DEFINE_DYNAMIC_DEBUG_METADATA_CLS to slurp any additional argument, which `pr_fmt` might add. Signed-off-by: Philipp Hahn <redacted> [pr_fmt change on test_dynamic_debug_submod instead of parent] Reviewed-by: Jim Cromie <jim.cromie@gmail.com> --- v10: . pass raw fmt to DEFINE_DYNAMIC_DEBUG_METADATA in pr_debug_ratelimited(). --- include/linux/dynamic_debug.h | 2 +- include/linux/printk.h | 2 +- lib/test_dynamic_debug.c | 4 ++-- .../selftests/dynamic_debug/dyndbg_selftest.sh | 26 +++++++++++----------- 4 files changed, 17 insertions(+), 17 deletions(-)
diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
index 2542d7c41b3e..d94ad3a2018a 100644
--- a/include/linux/dynamic_debug.h
+++ b/include/linux/dynamic_debug.h@@ -359,7 +359,7 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor, dump_stack(); \ } -#define DEFINE_DYNAMIC_DEBUG_METADATA_CLS(name, cls, fmt) \ +#define DEFINE_DYNAMIC_DEBUG_METADATA_CLS(name, cls, fmt, ...) \ static struct _ddebug __aligned(8) \ __section("__dyndbg_descs") name = { \ .modname = DDEBUG_MODNAME, \
diff --git a/include/linux/printk.h b/include/linux/printk.h
index f594c1266bfd..5d701952e739 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h@@ -742,7 +742,7 @@ do { \ static DEFINE_RATELIMIT_STATE(_rs, \ DEFAULT_RATELIMIT_INTERVAL, \ DEFAULT_RATELIMIT_BURST); \ - DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, pr_fmt(fmt)); \ + DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \ if (DYNAMIC_DEBUG_BRANCH(descriptor) && \ __ratelimit(&_rs)) \ __dynamic_pr_debug(&descriptor, pr_fmt(fmt), ##__VA_ARGS__); \
diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c
index fe5b885398f3..2710c4ea39a0 100644
--- a/lib/test_dynamic_debug.c
+++ b/lib/test_dynamic_debug.c@@ -23,7 +23,7 @@ * the usage clearer. */ #if defined(TEST_DYNAMIC_DEBUG_SUBMOD) - #define pr_fmt(fmt) "test_dd_submod: " fmt + #define pr_fmt(fmt) "test_dd_submod: %s " fmt, __func__ #else #define pr_fmt(fmt) "test_dd: " fmt #endif
@@ -272,7 +272,7 @@ static int __init test_dynamic_debug_init(void) static void __exit test_dynamic_debug_exit(void) { - pr_debug("exited\n"); + pr_debug_ratelimited("exited\n"); } module_init(test_dynamic_debug_init);
diff --git a/tools/testing/selftests/dynamic_debug/dyndbg_selftest.sh b/tools/testing/selftests/dynamic_debug/dyndbg_selftest.sh
index ef5f41ca7f7d..5eae762d6f78 100755
--- a/tools/testing/selftests/dynamic_debug/dyndbg_selftest.sh
+++ b/tools/testing/selftests/dynamic_debug/dyndbg_selftest.sh@@ -588,40 +588,40 @@ function GOLDEN_RECORDS { #K= 1d43471dca765597d88a1be25d776c92 FT_classmap_inheritance.2 #K= 0708a283f0f1959135c797e36119e4af FT_classmap_inheritance.3 #K= a0b9a8a9530706b85c4f8bf911607db0 FT_classmap_inheritance.4 -#K= f43e0aff8a4b38435b73d90ed8100d1b FT_classmap_inheritance.5 +#K= 62b6803edf43519186d6185bebf34352 FT_classmap_inheritance.5 #K= 53d1b6875b65c79cfd759e209ae50b11 FT_modprobe_w_param.1 #K= 53d1b6875b65c79cfd759e209ae50b11 FT_modprobe_w_param.2 -#K= 79d912e2aeb04dea70f9c7e701333f0a FT_modprobe_w_param.3 +#K= 117ebf415c886c14b22e473d9b49886b FT_modprobe_w_param.3 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.4 -#K= 7cd75277388a6e7cf9c849442388f4af FT_modprobe_w_param.5 +#K= 23bf93d8d91b2e033f91caf2e5d2df2c FT_modprobe_w_param.5 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.6 -#K= 9196c43693f5e6059f3512e4d87e7347 FT_modprobe_w_param.7 +#K= 7090bc68365ad55564c54b1ba7355c73 FT_modprobe_w_param.7 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.8 #K= f9cee4512e5604603e0262fba4bea223 FT_modprobe_w_param.9 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.10 -#K= 7c645692e3e3796d4d3b8604c49583f7 FT_modprobe_w_param.11 +#K= 076874eb43826e97586f034f4d2786e6 FT_modprobe_w_param.11 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.12 -#K= e995f70c0509334a33aec40ada9e6e6c FT_modprobe_w_param.13 +#K= 872dbd5d067953e34cd5a88db3a3b5e4 FT_modprobe_w_param.13 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.14 -#K= 72f97ca3e8f4c3e7f34fbe91de62e223 FT_modprobe_w_param.15 +#K= dce720419939a1baadaae27e98ceabea FT_modprobe_w_param.15 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.16 #K= 1aacb7c196a8354c46c60c73d78c6bf2 FT_modprobe_w_param.17 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.18 #K= e62014acf5ab6a76dfbfbcf67b2ca0e8 FT_modprobe_w_param.19 #K= e62014acf5ab6a76dfbfbcf67b2ca0e8 FT_modprobe_w_param.20 -#K= 58c009cb287fa5df3f8c1c72c832cb42 FT_modprobe_w_param.21 +#K= 4bfcf87a67b1a5a5a56212deac36c20a FT_modprobe_w_param.21 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.22 -#K= e7831be2aac4a82daba43966b9d31e19 FT_modprobe_w_param.23 +#K= f0d3016e22d88ee9f810b81235c6acdc FT_modprobe_w_param.23 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.24 -#K= 4df2fbc0cae329debb14bedb5e7d86c0 FT_modprobe_w_param.25 +#K= da3e0531675fc96503a7077ef8fa5eeb FT_modprobe_w_param.25 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.26 #K= 7fa4c84490c42c750986614c3539d56a FT_modprobe_w_param.27 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.28 -#K= fc098897aa3e1472a536e7ae8069c84f FT_modprobe_w_param.29 +#K= 923ca0e8a24d3e365b9dc89624062708 FT_modprobe_w_param.29 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.30 -#K= 38ea63fed62a0308241325e57020b28e FT_modprobe_w_param.31 +#K= 7eb76bdeb6e42f46e9c16b5932db79e1 FT_modprobe_w_param.31 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.32 -#K= 4b896adb5e7cfcc79f9ffa879d791f37 FT_modprobe_w_param.33 +#K= 5aaa5a8e367ec2871785f0c64853e243 FT_modprobe_w_param.33 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.34 #K= 7f961a7d3facd89bdd4b9d8e7b5541e9 FT_modprobe_w_param.35 #K= 6a320774e2b535ceb89d6cdde6f5d0fb FT_modprobe_w_param.36
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2.55.0