Currently, `struct ddebug_class_param` uses `unsigned long` pointers to store the state of `bits` and `lvl`. On 32-bit architectures, this limits the bit-vector to 32 bits, which truncates 64-bit classmaps (such as the one needed by `__drm_debug`).
To guarantee support for 64-bit debug categories across all architectures, upgrade the internal storage types in `struct _ddebug_class_param` to `u64`. This inherently makes both union members the same size while safely avoiding truncation. This includes: - Changing union members `bits` and `lvl` to `u64 *`. - Using `kstrtou64()` for sysfs input parsing. - Replacing array-based `test_bit()` operations with safe `u64` scalar bitwise logic (`!!(val & (1ULL << bi))`). - adjusting lib/test_dynamic_debug.c too Not yet done: - Updating `drm_print`'s `__drm_debug` to `u64` and configuring the associated module parameter as `ullong`. - Fixing an unused variable warning in `__drm_printfn_dbg`. Signed-off-by: Jim Cromie <[email protected]> --- v2: patch was "make bits & lvl same size" but that size was unsigned long, only 32 bits on i386 etc use u64 for all bits, and %llu %llx --- include/linux/dynamic_debug.h | 4 ++-- lib/dynamic_debug.c | 34 ++++++++++++++++++---------------- lib/test_dynamic_debug.c | 2 +- 3 files changed, 21 insertions(+), 19 deletions(-) diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index 0a137a586510..a84dcc127e5a 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -91,8 +91,8 @@ struct _ddebug_info { struct ddebug_class_param { union { - unsigned long *bits; - unsigned int *lvl; + u64 *bits; + u64 *lvl; }; char flags[8]; const struct ddebug_class_map *map; diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index e9481ef21825..580aa258f902 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -624,8 +624,7 @@ 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, - const unsigned long *new_bits, - const unsigned long old_bits, + const u64 *new_bits, const u64 old_bits, const char *query_modname) { #define QUERY_SIZE 128 @@ -635,24 +634,27 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, int bi, ct; if (*new_bits != old_bits) - v2pr_info("apply bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits, + v2pr_info("apply bitmap: 0x%llx to: 0x%llx for %s\n", *new_bits, old_bits, query_modname ?: "'*'"); for (bi = 0; bi < map->length; bi++) { - if (test_bit(bi, new_bits) == test_bit(bi, &old_bits)) + bool new_b = !!(*new_bits & (1ULL << bi)); + bool old_b = !!(old_bits & (1ULL << bi)); + + if (new_b == old_b) continue; snprintf(query, QUERY_SIZE, "class %s %c%s", map->class_names[bi], - test_bit(bi, new_bits) ? '+' : '-', dcp->flags); + new_b ? '+' : '-', dcp->flags); ct = ddebug_exec_queries(query, query_modname); matches += ct; - v2pr_info("bit_%d: %d matches on class: %s -> 0x%lx\n", bi, + v2pr_info("bit_%d: %d matches on class: %s -> 0x%llx\n", bi, ct, map->class_names[bi], *new_bits); } if (*new_bits != old_bits) - v2pr_info("applied bitmap: 0x%lx to: 0x%lx for %s\n", *new_bits, + v2pr_info("applied bitmap: 0x%llx to: 0x%llx for %s\n", *new_bits, old_bits, query_modname ?: "'*'"); return matches; @@ -661,7 +663,7 @@ static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, /* stub to later conditionally add "$module." prefix where not already done */ #define KP_NAME(kp) kp->name -#define CLASSMAP_BITMASK(width) ((1UL << (width)) - 1) +#define CLASSMAP_BITMASK(width) ((1ULL << (width)) - 1) /** * param_set_dyndbg_classes - class FOO >control @@ -681,10 +683,10 @@ static int param_set_dyndbg_module_classes(const char *instr, { const struct ddebug_class_param *dcp = kp->arg; const struct ddebug_class_map *map = dcp->map; - unsigned long inrep, new_bits, old_bits; + u64 inrep, new_bits, old_bits; int rc, totct = 0; - rc = kstrtoul(instr, 0, &inrep); + rc = kstrtou64(instr, 0, &inrep); if (rc) { int len = strcspn(instr, "\n"); pr_err("expecting numeric input, not: %.*s > %s\n", @@ -696,24 +698,24 @@ static int param_set_dyndbg_module_classes(const char *instr, case DD_CLASS_TYPE_DISJOINT_BITS: /* expect bits. mask and warn if too many */ if (inrep & ~CLASSMAP_BITMASK(map->length)) { - pr_warn("%s: input: 0x%lx exceeds mask: 0x%lx, masking\n", + pr_warn("%s: input: 0x%llx exceeds mask: 0x%llx, masking\n", KP_NAME(kp), inrep, CLASSMAP_BITMASK(map->length)); inrep &= CLASSMAP_BITMASK(map->length); } - v2pr_info("bits:0x%lx > %s.%s\n", inrep, mod_name ?: "*", KP_NAME(kp)); + v2pr_info("bits:0x%llx > %s.%s\n", inrep, mod_name ?: "*", KP_NAME(kp)); totct += ddebug_apply_class_bitmap(dcp, &inrep, *dcp->bits, mod_name); *dcp->bits = inrep; break; case DD_CLASS_TYPE_LEVEL_NUM: /* input is bitpos, of highest verbosity to be enabled */ if (inrep > map->length) { - pr_warn("%s: level:%ld exceeds max:%d, clamping\n", + pr_warn("%s: level:%llu exceeds max:%d, clamping\n", KP_NAME(kp), inrep, map->length); inrep = map->length; } 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)); + v2pr_info("lvl:%llu bits:0x%llx > %s\n", inrep, new_bits, KP_NAME(kp)); totct += ddebug_apply_class_bitmap(dcp, &new_bits, old_bits, mod_name); *dcp->lvl = inrep; break; @@ -759,9 +761,9 @@ int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp) switch (map->map_type) { case DD_CLASS_TYPE_DISJOINT_BITS: - return scnprintf(buffer, PAGE_SIZE, "0x%lx\n", *dcp->bits); + return scnprintf(buffer, PAGE_SIZE, "0x%llx\n", *dcp->bits); case DD_CLASS_TYPE_LEVEL_NUM: - return scnprintf(buffer, PAGE_SIZE, "%d\n", *dcp->lvl); + return scnprintf(buffer, PAGE_SIZE, "%llu\n", *dcp->lvl); default: return -1; } diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c index 74d183ebf3e0..c049580d2152 100644 --- a/lib/test_dynamic_debug.c +++ b/lib/test_dynamic_debug.c @@ -40,7 +40,7 @@ module_param_cb(do_prints, ¶m_ops_do_prints, NULL, 0600); * - tie together sysname, mapname, bitsname, flagsname */ #define DD_SYS_WRAP(_model, _flags) \ - static unsigned long bits_##_model; \ + static u64 bits_##_model; \ static struct ddebug_class_param _flags##_model = { \ .bits = &bits_##_model, \ .flags = #_flags, \ -- 2.54.0
