[PATCH v6 16/24] dyndbg: tighten fn-sig of ddebug_apply_class_bitmap
From: Jim Cromie <jim.cromie@gmail.com>
Date: 2026-07-08 02:19:01
Also in:
dri-devel, linux-arch, linux-doc, lkml
Subsystem:
dynamic debug, library code, the rest · Maintainers:
Jason Baron, Jim Cromie, Andrew Morton, Linus Torvalds
old_bits arg is currently a pointer to the input bits, but this could allow inadvertent changes to the input by the fn. Disallow this. And constify new_bits while here. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com> --- v2: move RvB after SoB --- lib/dynamic_debug.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-)
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 0fc9cd14e2d2..8c3b29904346 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c@@ -617,7 +617,8 @@ static int ddebug_exec_queries(char *query, const char *modname) /* apply a new class-param setting */ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, - unsigned long *new_bits, unsigned long *old_bits, + const unsigned long *new_bits, + const unsigned long old_bits, const char *query_modname) { #define QUERY_SIZE 128
@@ -626,12 +627,12 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, int matches = 0; int bi, ct; - if (*new_bits != *old_bits) + if (*new_bits != old_bits) v2pr_info("apply bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits, - *old_bits, query_modname ?: "'*'"); + old_bits, query_modname ?: "'*'"); for (bi = 0; bi < map->length; bi++) { - if (test_bit(bi, new_bits) == test_bit(bi, old_bits)) + if (test_bit(bi, new_bits) == test_bit(bi, &old_bits)) continue; snprintf(query, QUERY_SIZE, "class %s %c%s", map->class_names[bi],
@@ -643,9 +644,9 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, v2pr_info("bit_%d: %d matches on class: %s -> 0x%lx\n", bi, ct, map->class_names[bi], *new_bits); } - if (*new_bits != *old_bits) + if (*new_bits != old_bits) v2pr_info("applied bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits, - *old_bits, query_modname ?: "'*'"); + old_bits, query_modname ?: "'*'"); return matches; }
@@ -693,7 +694,7 @@ static int param_set_dyndbg_module_classes(const char *instr, inrep &= CLASSMAP_BITMASK(map->length); } v2pr_info("bits:0x%lx > %s.%s\n", inrep, mod_name ?: "*", KP_NAME(kp)); - totct += ddebug_apply_class_bitmap(dcp, &inrep, dcp->bits, mod_name); + totct += ddebug_apply_class_bitmap(dcp, &inrep, *dcp->bits, mod_name); *dcp->bits = inrep; break; case DD_CLASS_TYPE_LEVEL_NUM:
@@ -706,7 +707,7 @@ static int param_set_dyndbg_module_classes(const char *instr, old_bits = CLASSMAP_BITMASK(*dcp->lvl); new_bits = CLASSMAP_BITMASK(inrep); v2pr_info("lvl:%ld bits:0x%lx > %s\n", inrep, new_bits, KP_NAME(kp)); - totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits, mod_name); + totct += ddebug_apply_class_bitmap(dcp, &new_bits, old_bits, mod_name); *dcp->lvl = inrep; break; default:
--
2.55.0