From 22098763a10d9c1340827fcf6edab66f153b27f0 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 13 Sep 2026 12:27:00 -0700 Subject: Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Don't destroy user event fields when removal fails User event fields are destroyed before the event is removed from visibility. But that can fail leaving the still visible event with no fields. Move the destroying of the fields to after the event is successfully removed from visibility. - Initialize function graph state is fork before calling copy_exec_state() For non-CLONE_VM forks, copy_exec_state() allocates a new task_exec_state. If that allocation fails, ftrace_graph_exit_task() will free the tasks ret_stack pointer. Since that pointer is still using the parent's ret_stack, it mistakenly frees the parent's pointer too. Call ftrace_graph_init() on the task first which will NULL out the new tasks's ret_stack and if the copy fails, it will not free anything. - Remove FGRAPH_MAX_INDEX The macro FGRAPH_MAX_INDEX was added but never used. Remove it. - Save ent_size in function graph printing of nested functions The function graph tracer needs to look at the next event to see if the next event is the return of the current function entry. If it is, it prints a single line: ktime_get(); Otherwise it prints it like a nested function: tick_nohz_irq_exit() { ktime_get(); kcpustat_irq_exit(); } In order to look at the next event, it must save the current event so that it has the information to print from it. It saves the event in the iterator descriptor called "ent". What it doesn't save is the ent_size of the event which is now used to know if the function graph arguments are to be printed. The peek doesn't save the size so the size used happens to be that of the size of the last event that was seen. Save the entry event size in the iterator descriptor so that the correct size is used. - Fix several errors with freeing data in the histogram code The histogram code had a lot of leaked or or incorrect accounting when failures happen. Correct them. - Fix histogram regression of .percent and .graph modifiers Up until 6.3 histogram values could have "percent" or "graph" modifiers that changed how they were printed. But a change that added restricting histograms values from being strings, stack traces and other modifiers inadvertently prevented them from using the percent and graph modifiers, which were legal use cases for values. Put back the percent and graph modifiers. - Fix various typos in the comments - Set the trace_clock before initializing a histogram with clock argument The histogram API allows the user to specific which trace clock to use via a "clock=" string. The histogram is set up first before the clock is checked. If the passed in clock is not valid, it exits without fully fixing up the histogram leaving it on the list and a use-after-free can trigger. Update the clock argument first and if it fails then exit gracefully before the histogram trigger is placed on any lists. - Restore :mod: trailer after parsing in ftrace_set_clr_event The function ftrace_set_clr_event() modifies the parse string and needs to put it back to what was passed in. It searches for ":mod:" via a strsep() but fails to put back the first ':' in the string. Add back the ':' in the passed in string. - Take trace_array reference when opening a tracer options file The options files are dynamically created and some tracers add their own options. When a tracer adds their own list of options, the trace_array holding them has an array to hold the list of options for each tracer. This array increases in size via a krealloc(), and the new entry gets a newly allocated array to hold the options of the new tracer being added. The element in each entry of the tracer's option array holds a pointer back to the trace_array, a pointer to the tracer it is associated to, a pointer to the flags of the option. The issue is that these arrays are freed when the trace_array is freed when its instance it represents is removed from the instances directory. There's a race that an open of one of these options files can happen when the instance is being removed. Add a new helper function to be called by the open function of the options file to iterate all existing trace_arrays under a lock and find the one that has the given option element in one of it's tracer arrays. If found, then update the associated trace_array's reference counter to keep it from being freed. If not found, have the open call return -ENODEV. - Disable interrupts when acquiring the lock in rb_wake_up_waiters() The function rb_wake_up_waiters() assumes it will be called in interrupt context and does not disable irqs when taking cpu_buffer->reader_lock, which can be called in hard interrupt context. The issue is in PREEMPT_RT, this function is called in thread context leaving this lock open to a deadlock. Take the lock with interrupts disabled. - Use rcu_assign_pointer() for tmp_ops filter hash The tmp_ops used in update_ftrace_direct_mod() assigns its filter_hash field directly, but that field is annotated as __rcu and sparse complains. Assign it with rcu_assign_pointer() - Fix use-after-free in enable_trigger_private_data_free() The trace_event_call is accessed through the event_trigger_data's trace_event_file pointer to put the trace_event_call on freeing. The issue is that the trace_event_file data may have been freed already causing a use-after-free. Add a field to the event_trigger_data that points directly to the trace_event_call so that it can decrement its reference directly without needing to go through the trace_event_file. - Fix accounting of buffer data remote headers trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount the number of pages is needed for the asked for size as it doesn't take into account the meta data on each page. Add a helper function to do the calculation properly and use that in these functions. - Catch nr_page_va overflow in ring_buffer_desc sizing The number of pages per remote ring buffer is capped by ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to overflow that field would silently allocate a descriptor smaller than what was asked for. - Do not resize the subbuf order if any per_cpu buffer is disabled The mmapping of ring buffers disables resizing the subbuffers, but it is done per-cpu whereas the subbuf size change is done for all the per_cpu buffers under the buffer->mutex. It could change the size of some while the mapping is happening on others. Have the resize of the subbuf order check all the per_cpu buffers under the lock to see if any of them is disabled before starting and causing an inconsistency between buffers that are being mapped. * tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits) ring-buffer: Check resize_disabled before publishing the new subbuf order tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing tracing/remotes: Account for ring buffer page header in size calculation tracing: Don't dereference trace_event_file in deferred trigger free ftrace: Use rcu_assign_pointer() for tmp_ops filter hash ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters() tracing: Take trace_array reference when opening a tracer options file tracing: Fix ring_buffer_read_page_size() kernel-doc tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event() tracing: Fix memory corruption from a "STACKTRACE" histogram key tracing: Fix memory corruption from the histogram stacktrace modifier tracing: Undo the registration when enabling the histogram trigger fails tracing: Take the reference before publishing the named histogram trigger tracing: Set the trace clock before registering the histogram trigger tracing: Fix typo "preceeded" in comment tracing: Fix typo "availabe" in comment tracing: Let histogram values keep the percent and graph modifiers tracing: Keep the entry count when the histogram stats allocation fails tracing: Free histogram the field rejected for a bad modifier tracing: Free histogram the var ref when its initialization fails ... --- lib/dynamic_debug.c | 1495 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1495 insertions(+) create mode 100644 lib/dynamic_debug.c (limited to 'lib/dynamic_debug.c') diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c new file mode 100644 index 000000000..18a71a910 --- /dev/null +++ b/lib/dynamic_debug.c @@ -0,0 +1,1495 @@ +/* + * lib/dynamic_debug.c + * + * make pr_debug()/dev_dbg() calls runtime configurable based upon their + * source module. + * + * Copyright (C) 2008 Jason Baron + * By Greg Banks + * Copyright (c) 2008 Silicon Graphics Inc. All Rights Reserved. + * Copyright (C) 2011 Bart Van Assche. All Rights Reserved. + * Copyright (C) 2013 Du, Changbin + */ + +#define pr_fmt(fmt) "dyndbg: " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +extern struct _ddebug __start___dyndbg[]; +extern struct _ddebug __stop___dyndbg[]; +extern struct ddebug_class_map __start___dyndbg_classes[]; +extern struct ddebug_class_map __stop___dyndbg_classes[]; + +struct ddebug_table { + struct list_head link, maps; + const char *mod_name; + unsigned int num_ddebugs; + struct _ddebug *ddebugs; +}; + +struct ddebug_query { + const char *filename; + const char *module; + const char *function; + const char *format; + const char *class_string; + unsigned int first_lineno, last_lineno; +}; + +struct ddebug_iter { + struct ddebug_table *table; + int idx; +}; + +struct flag_settings { + unsigned int flags; + unsigned int mask; +}; + +static DEFINE_MUTEX(ddebug_lock); +static LIST_HEAD(ddebug_tables); +static int verbose; +module_param(verbose, int, 0644); +MODULE_PARM_DESC(verbose, " dynamic_debug/control processing " + "( 0 = off (default), 1 = module add/rm, 2 = >control summary, 3 = parsing, 4 = per-site changes)"); + +/* Return the path relative to source root */ +static inline const char *trim_prefix(const char *path) +{ + int skip = strlen(__FILE__) - strlen("lib/dynamic_debug.c"); + + if (strncmp(path, __FILE__, skip)) + skip = 0; /* prefix mismatch, don't skip */ + + return path + skip; +} + +static const struct { unsigned flag:8; char opt_char; } opt_array[] = { + { _DPRINTK_FLAGS_PRINT, 'p' }, + { _DPRINTK_FLAGS_INCL_MODNAME, 'm' }, + { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' }, + { _DPRINTK_FLAGS_INCL_SOURCENAME, 's' }, + { _DPRINTK_FLAGS_INCL_LINENO, 'l' }, + { _DPRINTK_FLAGS_INCL_TID, 't' }, + { _DPRINTK_FLAGS_INCL_STACK, 'd' }, + { _DPRINTK_FLAGS_NONE, '_' }, +}; + +struct flagsbuf { char buf[ARRAY_SIZE(opt_array)+1]; }; + +/* format a string into buf[] which describes the _ddebug's flags */ +static char *ddebug_describe_flags(unsigned int flags, struct flagsbuf *fb) +{ + char *p = fb->buf; + int i; + + for (i = 0; i < ARRAY_SIZE(opt_array); ++i) + if (flags & opt_array[i].flag) + *p++ = opt_array[i].opt_char; + if (p == fb->buf) + *p++ = '_'; + *p = '\0'; + + return fb->buf; +} + +#define vnpr_info(lvl, fmt, ...) \ +do { \ + if (verbose >= lvl) \ + pr_info(fmt, ##__VA_ARGS__); \ +} while (0) + +#define vpr_info(fmt, ...) vnpr_info(1, fmt, ##__VA_ARGS__) +#define v2pr_info(fmt, ...) vnpr_info(2, fmt, ##__VA_ARGS__) +#define v3pr_info(fmt, ...) vnpr_info(3, fmt, ##__VA_ARGS__) +#define v4pr_info(fmt, ...) vnpr_info(4, fmt, ##__VA_ARGS__) + +static void vpr_info_dq(const struct ddebug_query *query, const char *msg) +{ + /* trim any trailing newlines */ + int fmtlen = 0; + + if (query->format) { + fmtlen = strlen(query->format); + while (fmtlen && query->format[fmtlen - 1] == '\n') + fmtlen--; + } + + v3pr_info("%s: func=\"%s\" file=\"%s\" module=\"%s\" format=\"%.*s\" lineno=%u-%u class=%s\n", + msg, + query->function ?: "", + query->filename ?: "", + query->module ?: "", + fmtlen, query->format ?: "", + query->first_lineno, query->last_lineno, query->class_string); +} + +static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table const *dt, + const char *class_string, int *class_id) +{ + struct ddebug_class_map *map; + int idx; + + list_for_each_entry(map, &dt->maps, link) { + idx = match_string(map->class_names, map->length, class_string); + if (idx >= 0) { + *class_id = idx + map->base; + return map; + } + } + *class_id = -ENOENT; + return NULL; +} + +#define __outvar /* filled by callee */ +/* + * Search the tables for _ddebug's which match the given `query' and + * apply the `flags' and `mask' to them. Returns number of matching + * callsites, normally the same as number of changes. If verbose, + * logs the changes. Takes ddebug_lock. + */ +static int ddebug_change(const struct ddebug_query *query, + struct flag_settings *modifiers) +{ + int i; + struct ddebug_table *dt; + unsigned int newflags; + unsigned int nfound = 0; + struct flagsbuf fbuf, nbuf; + struct ddebug_class_map *map = NULL; + int __outvar valid_class; + + /* search for matching ddebugs */ + mutex_lock(&ddebug_lock); + list_for_each_entry(dt, &ddebug_tables, link) { + + /* match against the module name */ + if (query->module && + !match_wildcard(query->module, dt->mod_name)) + continue; + + if (query->class_string) { + map = ddebug_find_valid_class(dt, query->class_string, &valid_class); + if (!map) + continue; + } else { + /* constrain query, do not touch class'd callsites */ + valid_class = _DPRINTK_CLASS_DFLT; + } + + for (i = 0; i < dt->num_ddebugs; i++) { + struct _ddebug *dp = &dt->ddebugs[i]; + + /* match site against query-class */ + if (dp->class_id != valid_class) + continue; + + /* match against the source filename */ + if (query->filename && + !match_wildcard(query->filename, dp->filename) && + !match_wildcard(query->filename, + kbasename(dp->filename)) && + !match_wildcard(query->filename, + trim_prefix(dp->filename))) + continue; + + /* match against the function */ + if (query->function && + !match_wildcard(query->function, dp->function)) + continue; + + /* match against the format */ + if (query->format) { + if (*query->format == '^') { + char *p; + /* anchored search. match must be at beginning */ + p = strstr(dp->format, query->format+1); + if (p != dp->format) + continue; + } else if (!strstr(dp->format, query->format)) + continue; + } + + /* match against the line number range */ + if (query->first_lineno && + dp->lineno < query->first_lineno) + continue; + if (query->last_lineno && + dp->lineno > query->last_lineno) + continue; + + nfound++; + + newflags = (dp->flags & modifiers->mask) | modifiers->flags; + if (newflags == dp->flags) + continue; +#ifdef CONFIG_JUMP_LABEL + if (dp->flags & _DPRINTK_FLAGS_PRINT) { + if (!(newflags & _DPRINTK_FLAGS_PRINT)) + static_branch_disable(&dp->key.dd_key_true); + } else if (newflags & _DPRINTK_FLAGS_PRINT) { + static_branch_enable(&dp->key.dd_key_true); + } +#endif + v4pr_info("changed %s:%d [%s]%s %s => %s\n", + trim_prefix(dp->filename), dp->lineno, + dt->mod_name, dp->function, + ddebug_describe_flags(dp->flags, &fbuf), + ddebug_describe_flags(newflags, &nbuf)); + dp->flags = newflags; + } + } + mutex_unlock(&ddebug_lock); + + if (!nfound && verbose) + pr_info("no matches for query\n"); + + return nfound; +} + +/* + * Split the buffer `buf' into space-separated words. + * Handles simple " and ' quoting, i.e. without nested, + * embedded or escaped \". Return the number of words + * or <0 on error. + */ +static int ddebug_tokenize(char *buf, char *words[], int maxwords) +{ + int nwords = 0; + + while (*buf) { + char *end; + + /* Skip leading whitespace */ + buf = skip_spaces(buf); + if (!*buf) + break; /* oh, it was trailing whitespace */ + if (*buf == '#') + break; /* token starts comment, skip rest of line */ + + /* find `end' of word, whitespace separated or quoted */ + if (*buf == '"' || *buf == '\'') { + int quote = *buf++; + for (end = buf; *end && *end != quote; end++) + ; + if (!*end) { + pr_err("unclosed quote: %s\n", buf); + return -EINVAL; /* unclosed quote */ + } + } else { + for (end = buf; *end && !isspace(*end); end++) + ; + if (end == buf) { + pr_err("parse err after word:%d=%s\n", nwords, + nwords ? words[nwords - 1] : ""); + return -EINVAL; + } + } + + /* `buf' is start of word, `end' is one past its end */ + if (nwords == maxwords) { + pr_err("too many words, legal max <=%d\n", maxwords); + return -EINVAL; /* ran out of words[] before bytes */ + } + if (*end) + *end++ = '\0'; /* terminate the word */ + words[nwords++] = buf; + buf = end; + } + + if (verbose >= 3) { + int i; + pr_info("split into words:"); + for (i = 0; i < nwords; i++) + pr_cont(" \"%s\"", words[i]); + pr_cont("\n"); + } + + return nwords; +} + +/* + * Parse a single line number. Note that the empty string "" + * is treated as a special case and converted to zero, which + * is later treated as a "don't care" value. + */ +static inline int parse_lineno(const char *str, unsigned int *val) +{ + BUG_ON(str == NULL); + if (*str == '\0') { + *val = 0; + return 0; + } + if (kstrtouint(str, 10, val) < 0) { + pr_err("bad line-number: %s\n", str); + return -EINVAL; + } + return 0; +} + +static int parse_linerange(struct ddebug_query *query, const char *first) +{ + char *last = strchr(first, '-'); + + if (query->first_lineno || query->last_lineno) { + pr_err("match-spec: line used 2x\n"); + return -EINVAL; + } + if (last) + *last++ = '\0'; + if (parse_lineno(first, &query->first_lineno) < 0) + return -EINVAL; + if (last) { + /* range - */ + if (parse_lineno(last, &query->last_lineno) < 0) + return -EINVAL; + + /* special case for last lineno not specified */ + if (query->last_lineno == 0) + query->last_lineno = UINT_MAX; + + if (query->last_lineno < query->first_lineno) { + pr_err("last-line:%d < 1st-line:%d\n", + query->last_lineno, + query->first_lineno); + return -EINVAL; + } + } else { + query->last_lineno = query->first_lineno; + } + v3pr_info("parsed line %d-%d\n", query->first_lineno, + query->last_lineno); + return 0; +} + +static int check_set(const char **dest, char *src, char *name) +{ + int rc = 0; + + if (*dest) { + rc = -EINVAL; + pr_err("match-spec:%s val:%s overridden by %s\n", + name, *dest, src); + } + *dest = src; + return rc; +} + +/* + * Parse words[] as a ddebug query specification, which is a series + * of (keyword, value) pairs chosen from these possibilities: + * + * func + * file + * file + * module + * format + * line + * line - // where either may be empty + * + * Only 1 of each type is allowed. + * Returns 0 on success, <0 on error. + */ +static int ddebug_parse_query(char *words[], int nwords, + struct ddebug_query *query, const char *modname) +{ + unsigned int i; + int rc = 0; + char *fline; + + /* check we have an even number of words */ + if (nwords % 2 != 0) { + pr_err("expecting pairs of match-spec \n"); + return -EINVAL; + } + + for (i = 0; i < nwords; i += 2) { + char *keyword = words[i]; + char *arg = words[i+1]; + + if (!strcmp(keyword, "func")) { + rc = check_set(&query->function, arg, "func"); + } else if (!strcmp(keyword, "file")) { + if (check_set(&query->filename, arg, "file")) + return -EINVAL; + + /* tail :$info is function or line-range */ + fline = strchr(query->filename, ':'); + if (!fline) + continue; + *fline++ = '\0'; + if (isalpha(*fline) || *fline == '*' || *fline == '?') { + /* take as function name */ + if (check_set(&query->function, fline, "func")) + return -EINVAL; + } else { + if (parse_linerange(query, fline)) + return -EINVAL; + } + } else if (!strcmp(keyword, "module")) { + rc = check_set(&query->module, arg, "module"); + } else if (!strcmp(keyword, "format")) { + string_unescape_inplace(arg, UNESCAPE_SPACE | + UNESCAPE_OCTAL | + UNESCAPE_SPECIAL); + rc = check_set(&query->format, arg, "format"); + } else if (!strcmp(keyword, "line")) { + if (parse_linerange(query, arg)) + return -EINVAL; + } else if (!strcmp(keyword, "class")) { + rc = check_set(&query->class_string, arg, "class"); + } else { + pr_err("unknown keyword \"%s\"\n", keyword); + return -EINVAL; + } + if (rc) + return rc; + } + if (!query->module && modname) + /* + * support $modname.dyndbg=, when + * not given in the query itself + */ + query->module = modname; + + vpr_info_dq(query, "parsed"); + return 0; +} + +/* + * Parse `str' as a flags specification, format [-+=][p]+. + * Sets up *maskp and *flagsp to be used when changing the + * flags fields of matched _ddebug's. Returns 0 on success + * or <0 on error. + */ +static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers) +{ + int op, i; + + switch (*str) { + case '+': + case '-': + case '=': + op = *str++; + break; + default: + pr_err("bad flag-op %c, at start of %s\n", *str, str); + return -EINVAL; + } + v3pr_info("op='%c'\n", op); + + for (; *str ; ++str) { + for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) { + if (*str == opt_array[i].opt_char) { + modifiers->flags |= opt_array[i].flag; + break; + } + } + if (i < 0) { + pr_err("unknown flag '%c'\n", *str); + return -EINVAL; + } + } + v3pr_info("flags=0x%x\n", modifiers->flags); + + /* calculate final flags, mask based upon op */ + switch (op) { + case '=': + /* modifiers->flags already set */ + modifiers->mask = 0; + break; + case '+': + modifiers->mask = ~0U; + break; + case '-': + modifiers->mask = ~modifiers->flags; + modifiers->flags = 0; + break; + } + v3pr_info("*flagsp=0x%x *maskp=0x%x\n", modifiers->flags, modifiers->mask); + + return 0; +} + +static int ddebug_exec_query(char *query_string, const char *modname) +{ + struct flag_settings modifiers = {}; + struct ddebug_query query = {}; +#define MAXWORDS 9 + int nwords, nfound; + char *words[MAXWORDS]; + + nwords = ddebug_tokenize(query_string, words, MAXWORDS); + if (nwords <= 0) { + pr_err("tokenize failed\n"); + return -EINVAL; + } + /* check flags 1st (last arg) so query is pairs of spec,val */ + if (ddebug_parse_flags(words[nwords-1], &modifiers)) { + pr_err("flags parse failed\n"); + return -EINVAL; + } + if (ddebug_parse_query(words, nwords-1, &query, modname)) { + pr_err("query parse failed\n"); + return -EINVAL; + } + /* actually go and implement the change */ + nfound = ddebug_change(&query, &modifiers); + vpr_info_dq(&query, nfound ? "applied" : "no-match"); + + return nfound; +} + +/* handle multiple queries in query string, continue on error, return + last error or number of matching callsites. Module name is either + in param (for boot arg) or perhaps in query string. +*/ +static int ddebug_exec_queries(char *query, const char *modname) +{ + char *split; + int i, errs = 0, exitcode = 0, rc, nfound = 0; + + for (i = 0; query; query = split) { + split = strpbrk(query, ";\n"); + if (split) + *split++ = '\0'; + + query = skip_spaces(query); + if (!query || !*query || *query == '#') + continue; + + vpr_info("query %d: \"%s\" mod:%s\n", i, query, modname ?: "*"); + + rc = ddebug_exec_query(query, modname); + if (rc < 0) { + errs++; + exitcode = rc; + } else { + nfound += rc; + } + i++; + } + if (i) + v2pr_info("processed %d queries, with %d matches, %d errs\n", + i, nfound, errs); + + if (exitcode) + return exitcode; + return nfound; +} + +/* apply a new bitmap to the sys-knob's current bit-state */ +static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, + unsigned long *new_bits, unsigned long *old_bits) +{ +#define QUERY_SIZE 128 + char query[QUERY_SIZE]; + const struct ddebug_class_map *map = dcp->map; + int matches = 0; + int bi, ct; + + v2pr_info("apply: 0x%lx to: 0x%lx\n", *new_bits, *old_bits); + + for (bi = 0; bi < map->length; bi++) { + if (test_bit(bi, new_bits) == test_bit(bi, old_bits)) + continue; + + snprintf(query, QUERY_SIZE, "class %s %c%s", map->class_names[bi], + test_bit(bi, new_bits) ? '+' : '-', dcp->flags); + + ct = ddebug_exec_queries(query, NULL); + matches += ct; + + v2pr_info("bit_%d: %d matches on class: %s -> 0x%lx\n", bi, + ct, map->class_names[bi], *new_bits); + } + return matches; +} + +/* stub to later conditionally add "$module." prefix where not already done */ +#define KP_NAME(kp) kp->name + +#define CLASSMAP_BITMASK(width) ((1UL << (width)) - 1) + +/* accept comma-separated-list of [+-] classnames */ +static int param_set_dyndbg_classnames(const char *instr, const struct kernel_param *kp) +{ + const struct ddebug_class_param *dcp = kp->arg; + const struct ddebug_class_map *map = dcp->map; + unsigned long curr_bits, old_bits; + char *cl_str, *p, *tmp; + int cls_id, totct = 0; + bool wanted; + + cl_str = tmp = kstrdup_and_replace(instr, '\n', '\0', GFP_KERNEL); + if (!tmp) + return -ENOMEM; + + /* start with previously set state-bits, then modify */ + curr_bits = old_bits = *dcp->bits; + vpr_info("\"%s\" > %s:0x%lx\n", cl_str, KP_NAME(kp), curr_bits); + + for (; cl_str; cl_str = p) { + p = strchr(cl_str, ','); + if (p) + *p++ = '\0'; + + if (*cl_str == '-') { + wanted = false; + cl_str++; + } else { + wanted = true; + if (*cl_str == '+') + cl_str++; + } + cls_id = match_string(map->class_names, map->length, cl_str); + if (cls_id < 0) { + pr_err("%s unknown to %s\n", cl_str, KP_NAME(kp)); + continue; + } + + /* have one or more valid class_ids of one *_NAMES type */ + switch (map->map_type) { + case DD_CLASS_TYPE_DISJOINT_NAMES: + /* the +/- pertains to a single bit */ + if (test_bit(cls_id, &curr_bits) == wanted) { + v3pr_info("no change on %s\n", cl_str); + continue; + } + curr_bits ^= BIT(cls_id); + totct += ddebug_apply_class_bitmap(dcp, &curr_bits, dcp->bits); + *dcp->bits = curr_bits; + v2pr_info("%s: changed bit %d:%s\n", KP_NAME(kp), cls_id, + map->class_names[cls_id]); + break; + case DD_CLASS_TYPE_LEVEL_NAMES: + /* cls_id = N in 0..max. wanted +/- determines N or N-1 */ + old_bits = CLASSMAP_BITMASK(*dcp->lvl); + curr_bits = CLASSMAP_BITMASK(cls_id + (wanted ? 1 : 0 )); + + totct += ddebug_apply_class_bitmap(dcp, &curr_bits, &old_bits); + *dcp->lvl = (cls_id + (wanted ? 1 : 0)); + v2pr_info("%s: changed bit-%d: \"%s\" %lx->%lx\n", KP_NAME(kp), cls_id, + map->class_names[cls_id], old_bits, curr_bits); + break; + default: + pr_err("illegal map-type value %d\n", map->map_type); + } + } + kfree(tmp); + vpr_info("total matches: %d\n", totct); + return 0; +} + +/** + * param_set_dyndbg_classes - class FOO >control + * @instr: string echo>d to sysfs, input depends on map_type + * @kp: kp->arg has state: bits/lvl, map, map_type + * + * Enable/disable prdbgs by their class, as given in the arguments to + * DECLARE_DYNDBG_CLASSMAP. For LEVEL map-types, enforce relative + * levels by bitpos. + * + * Returns: 0 or <0 if error. + */ +int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) +{ + const struct ddebug_class_param *dcp = kp->arg; + const struct ddebug_class_map *map = dcp->map; + unsigned long inrep, new_bits, old_bits; + int rc, totct = 0; + + switch (map->map_type) { + + case DD_CLASS_TYPE_DISJOINT_NAMES: + case DD_CLASS_TYPE_LEVEL_NAMES: + /* handle [+-]classnames list separately, we are done here */ + return param_set_dyndbg_classnames(instr, kp); + + case DD_CLASS_TYPE_DISJOINT_BITS: + case DD_CLASS_TYPE_LEVEL_NUM: + /* numeric input, accept and fall-thru */ + rc = kstrtoul(instr, 0, &inrep); + if (rc) { + pr_err("expecting numeric input: %s > %s\n", instr, KP_NAME(kp)); + return -EINVAL; + } + break; + default: + pr_err("%s: bad map type: %d\n", KP_NAME(kp), map->map_type); + return -EINVAL; + } + + /* only _BITS,_NUM (numeric) map-types get here */ + switch (map->map_type) { + 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", + KP_NAME(kp), inrep, CLASSMAP_BITMASK(map->length)); + inrep &= CLASSMAP_BITMASK(map->length); + } + v2pr_info("bits:%lx > %s\n", inrep, KP_NAME(kp)); + totct += ddebug_apply_class_bitmap(dcp, &inrep, dcp->bits); + *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", + 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)); + totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits); + *dcp->lvl = inrep; + break; + default: + pr_warn("%s: bad map type: %d\n", KP_NAME(kp), map->map_type); + } + vpr_info("%s: total matches: %d\n", KP_NAME(kp), totct); + return 0; +} +EXPORT_SYMBOL(param_set_dyndbg_classes); + +/** + * param_get_dyndbg_classes - classes reader + * @buffer: string description of controlled bits -> classes + * @kp: kp->arg has state: bits, map + * + * Reads last written state, underlying prdbg state may have been + * altered by direct >control. Displays 0x for DISJOINT, 0-N for + * LEVEL Returns: #chars written or <0 on error + */ +int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp) +{ + const struct ddebug_class_param *dcp = kp->arg; + const struct ddebug_class_map *map = dcp->map; + + switch (map->map_type) { + + case DD_CLASS_TYPE_DISJOINT_NAMES: + case DD_CLASS_TYPE_DISJOINT_BITS: + return scnprintf(buffer, PAGE_SIZE, "0x%lx\n", *dcp->bits); + + case DD_CLASS_TYPE_LEVEL_NAMES: + case DD_CLASS_TYPE_LEVEL_NUM: + return scnprintf(buffer, PAGE_SIZE, "%d\n", *dcp->lvl); + default: + return -1; + } +} +EXPORT_SYMBOL(param_get_dyndbg_classes); + +const struct kernel_param_ops param_ops_dyndbg_classes = { + .set = param_set_dyndbg_classes, + .get = param_get_dyndbg_classes, +}; +EXPORT_SYMBOL(param_ops_dyndbg_classes); + +#define PREFIX_SIZE 128 + +static int remaining(int wrote) +{ + if (PREFIX_SIZE - wrote > 0) + return PREFIX_SIZE - wrote; + return 0; +} + +static char *__dynamic_emit_prefix(const struct _ddebug *desc, char *buf) +{ + int pos_after_tid; + int pos = 0; + + if (desc->flags & _DPRINTK_FLAGS_INCL_TID) { + if (in_interrupt()) + pos += snprintf(buf + pos, remaining(pos), " "); + else + pos += snprintf(buf + pos, remaining(pos), "[%d] ", + task_pid_vnr(current)); + } + pos_after_tid = pos; + if (desc->flags & _DPRINTK_FLAGS_INCL_MODNAME) + pos += snprintf(buf + pos, remaining(pos), "%s:", + desc->modname); + if (desc->flags & _DPRINTK_FLAGS_INCL_FUNCNAME) + pos += snprintf(buf + pos, remaining(pos), "%s:", + desc->function); + if (desc->flags & _DPRINTK_FLAGS_INCL_SOURCENAME) + pos += snprintf(buf + pos, remaining(pos), "%s:", + trim_prefix(desc->filename)); + if (desc->flags & _DPRINTK_FLAGS_INCL_LINENO) + pos += snprintf(buf + pos, remaining(pos), "%d:", + desc->lineno); + if (pos - pos_after_tid) + pos += snprintf(buf + pos, remaining(pos), " "); + if (pos >= PREFIX_SIZE) + buf[PREFIX_SIZE - 1] = '\0'; + + return buf; +} + +static inline char *dynamic_emit_prefix(struct _ddebug *desc, char *buf) +{ + if (unlikely(desc->flags & _DPRINTK_FLAGS_INCL_ANY)) + return __dynamic_emit_prefix(desc, buf); + return buf; +} + +void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...) +{ + va_list args; + struct va_format vaf; + char buf[PREFIX_SIZE] = ""; + + BUG_ON(!descriptor); + BUG_ON(!fmt); + + va_start(args, fmt); + + vaf.fmt = fmt; + vaf.va = &args; + + printk(KERN_DEBUG "%s%pV", dynamic_emit_prefix(descriptor, buf), &vaf); + + va_end(args); +} +EXPORT_SYMBOL(__dynamic_pr_debug); + +void __dynamic_dev_dbg(struct _ddebug *descriptor, + const struct device *dev, const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + BUG_ON(!descriptor); + BUG_ON(!fmt); + + va_start(args, fmt); + + vaf.fmt = fmt; + vaf.va = &args; + + if (!dev) { + printk(KERN_DEBUG "(NULL device *): %pV", &vaf); + } else { + char buf[PREFIX_SIZE] = ""; + + dev_printk_emit(LOGLEVEL_DEBUG, dev, "%s%s %s: %pV", + dynamic_emit_prefix(descriptor, buf), + dev_driver_string(dev), dev_name(dev), + &vaf); + } + + va_end(args); +} +EXPORT_SYMBOL(__dynamic_dev_dbg); + +#ifdef CONFIG_NET + +void __dynamic_netdev_dbg(struct _ddebug *descriptor, + const struct net_device *dev, const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + BUG_ON(!descriptor); + BUG_ON(!fmt); + + va_start(args, fmt); + + vaf.fmt = fmt; + vaf.va = &args; + + if (dev && dev->dev.parent) { + char buf[PREFIX_SIZE] = ""; + + dev_printk_emit(LOGLEVEL_DEBUG, dev->dev.parent, + "%s%s %s %s%s: %pV", + dynamic_emit_prefix(descriptor, buf), + dev_driver_string(dev->dev.parent), + dev_name(dev->dev.parent), + netdev_name(dev), netdev_reg_state(dev), + &vaf); + } else if (dev) { + printk(KERN_DEBUG "%s%s: %pV", netdev_name(dev), + netdev_reg_state(dev), &vaf); + } else { + printk(KERN_DEBUG "(NULL net_device): %pV", &vaf); + } + + va_end(args); +} +EXPORT_SYMBOL(__dynamic_netdev_dbg); + +#endif + +#if IS_ENABLED(CONFIG_INFINIBAND) + +void __dynamic_ibdev_dbg(struct _ddebug *descriptor, + const struct ib_device *ibdev, const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, fmt); + + vaf.fmt = fmt; + vaf.va = &args; + + if (ibdev && ibdev->dev.parent) { + char buf[PREFIX_SIZE] = ""; + + dev_printk_emit(LOGLEVEL_DEBUG, ibdev->dev.parent, + "%s%s %s %s: %pV", + dynamic_emit_prefix(descriptor, buf), + dev_driver_string(ibdev->dev.parent), + dev_name(ibdev->dev.parent), + dev_name(&ibdev->dev), + &vaf); + } else if (ibdev) { + printk(KERN_DEBUG "%s: %pV", dev_name(&ibdev->dev), &vaf); + } else { + printk(KERN_DEBUG "(NULL ib_device): %pV", &vaf); + } + + va_end(args); +} +EXPORT_SYMBOL(__dynamic_ibdev_dbg); + +#endif + +/* + * Install a noop handler to make dyndbg look like a normal kernel cli param. + * This avoids warnings about dyndbg being an unknown cli param when supplied + * by a user. + */ +static __init int dyndbg_setup(char *str) +{ + return 1; +} + +__setup("dyndbg=", dyndbg_setup); + +/* + * File_ops->write method for /dynamic_debug/control. Gathers the + * command text from userspace, parses and executes it. + */ +#define USER_BUF_PAGE 4096 +static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf, + size_t len, loff_t *offp) +{ + char *tmpbuf; + int ret; + + if (len == 0) + return 0; + if (len > USER_BUF_PAGE - 1) { + pr_warn("expected <%d bytes into control\n", USER_BUF_PAGE); + return -E2BIG; + } + tmpbuf = memdup_user_nul(ubuf, len); + if (IS_ERR(tmpbuf)) + return PTR_ERR(tmpbuf); + v2pr_info("read %zu bytes from userspace\n", len); + + ret = ddebug_exec_queries(tmpbuf, NULL); + kfree(tmpbuf); + if (ret < 0) + return ret; + + *offp += len; + return len; +} + +/* + * Set the iterator to point to the first _ddebug object + * and return a pointer to that first object. Returns + * NULL if there are no _ddebugs at all. + */ +static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter) +{ + if (list_empty(&ddebug_tables)) { + iter->table = NULL; + return NULL; + } + iter->table = list_entry(ddebug_tables.next, + struct ddebug_table, link); + iter->idx = iter->table->num_ddebugs; + return &iter->table->ddebugs[--iter->idx]; +} + +/* + * Advance the iterator to point to the next _ddebug + * object from the one the iterator currently points at, + * and returns a pointer to the new _ddebug. Returns + * NULL if the iterator has seen all the _ddebugs. + */ +static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter) +{ + if (iter->table == NULL) + return NULL; + if (--iter->idx < 0) { + /* iterate to next table */ + if (list_is_last(&iter->table->link, &ddebug_tables)) { + iter->table = NULL; + return NULL; + } + iter->table = list_entry(iter->table->link.next, + struct ddebug_table, link); + iter->idx = iter->table->num_ddebugs; + --iter->idx; + } + return &iter->table->ddebugs[iter->idx]; +} + +/* + * Seq_ops start method. Called at the start of every + * read() call from userspace. Takes the ddebug_lock and + * seeks the seq_file's iterator to the given position. + */ +static void *ddebug_proc_start(struct seq_file *m, loff_t *pos) +{ + struct ddebug_iter *iter = m->private; + struct _ddebug *dp; + int n = *pos; + + mutex_lock(&ddebug_lock); + + if (!n) + return SEQ_START_TOKEN; + if (n < 0) + return NULL; + dp = ddebug_iter_first(iter); + while (dp != NULL && --n > 0) + dp = ddebug_iter_next(iter); + return dp; +} + +/* + * Seq_ops next method. Called several times within a read() + * call from userspace, with ddebug_lock held. Walks to the + * next _ddebug object with a special case for the header line. + */ +static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos) +{ + struct ddebug_iter *iter = m->private; + struct _ddebug *dp; + + if (p == SEQ_START_TOKEN) + dp = ddebug_iter_first(iter); + else + dp = ddebug_iter_next(iter); + ++*pos; + return dp; +} + +#define class_in_range(class_id, map) \ + (class_id >= map->base && class_id < map->base + map->length) + +static const char *ddebug_class_name(struct ddebug_iter *iter, struct _ddebug *dp) +{ + struct ddebug_class_map *map; + + list_for_each_entry(map, &iter->table->maps, link) + if (class_in_range(dp->class_id, map)) + return map->class_names[dp->class_id - map->base]; + + return NULL; +} + +/* + * Seq_ops show method. Called several times within a read() + * call from userspace, with ddebug_lock held. Formats the + * current _ddebug as a single human-readable line, with a + * special case for the header line. + */ +static int ddebug_proc_show(struct seq_file *m, void *p) +{ + struct ddebug_iter *iter = m->private; + struct _ddebug *dp = p; + struct flagsbuf flags; + char const *class; + + if (p == SEQ_START_TOKEN) { + seq_puts(m, + "# filename:lineno [module]function flags format\n"); + return 0; + } + + seq_printf(m, "%s:%u [%s]%s =%s \"", + trim_prefix(dp->filename), dp->lineno, + iter->table->mod_name, dp->function, + ddebug_describe_flags(dp->flags, &flags)); + seq_escape_str(m, dp->format, ESCAPE_SPACE, "\t\r\n\""); + seq_putc(m, '"'); + + if (dp->class_id != _DPRINTK_CLASS_DFLT) { + class = ddebug_class_name(iter, dp); + if (class) + seq_printf(m, " class:%s", class); + else + seq_printf(m, " class unknown, _id:%d", dp->class_id); + } + seq_putc(m, '\n'); + + return 0; +} + +/* + * Seq_ops stop method. Called at the end of each read() + * call from userspace. Drops ddebug_lock. + */ +static void ddebug_proc_stop(struct seq_file *m, void *p) +{ + mutex_unlock(&ddebug_lock); +} + +static const struct seq_operations ddebug_proc_seqops = { + .start = ddebug_proc_start, + .next = ddebug_proc_next, + .show = ddebug_proc_show, + .stop = ddebug_proc_stop +}; + +static int ddebug_proc_open(struct inode *inode, struct file *file) +{ + return seq_open_private(file, &ddebug_proc_seqops, + sizeof(struct ddebug_iter)); +} + +static const struct file_operations ddebug_proc_fops = { + .owner = THIS_MODULE, + .open = ddebug_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release_private, + .write = ddebug_proc_write +}; + +static const struct proc_ops proc_fops = { + .proc_open = ddebug_proc_open, + .proc_read = seq_read, + .proc_lseek = seq_lseek, + .proc_release = seq_release_private, + .proc_write = ddebug_proc_write +}; + +static void ddebug_attach_module_classes(struct ddebug_table *dt, + struct ddebug_class_map *classes, + int num_classes) +{ + struct ddebug_class_map *cm; + int i, j, ct = 0; + + for (cm = classes, i = 0; i < num_classes; i++, cm++) { + + if (!strcmp(cm->mod_name, dt->mod_name)) { + + v2pr_info("class[%d]: module:%s base:%d len:%d ty:%d\n", i, + cm->mod_name, cm->base, cm->length, cm->map_type); + + for (j = 0; j < cm->length; j++) + v3pr_info(" %d: %d %s\n", j + cm->base, j, + cm->class_names[j]); + + list_add(&cm->link, &dt->maps); + ct++; + } + } + if (ct) + vpr_info("module:%s attached %d classes\n", dt->mod_name, ct); +} + +/* + * Allocate a new ddebug_table for the given module + * and add it to the global list. + */ +static int ddebug_add_module(struct _ddebug_info *di, const char *modname) +{ + struct ddebug_table *dt; + + v3pr_info("add-module: %s.%d sites\n", modname, di->num_descs); + if (!di->num_descs) { + v3pr_info(" skip %s\n", modname); + return 0; + } + + dt = kzalloc_obj(*dt); + if (dt == NULL) { + pr_err("error adding module: %s\n", modname); + return -ENOMEM; + } + /* + * For built-in modules, name lives in .rodata and is + * immortal. For loaded modules, name points at the name[] + * member of struct module, which lives at least as long as + * this struct ddebug_table. + */ + dt->mod_name = modname; + dt->ddebugs = di->descs; + dt->num_ddebugs = di->num_descs; + + INIT_LIST_HEAD(&dt->link); + INIT_LIST_HEAD(&dt->maps); + + if (di->classes && di->num_classes) + ddebug_attach_module_classes(dt, di->classes, di->num_classes); + + mutex_lock(&ddebug_lock); + list_add_tail(&dt->link, &ddebug_tables); + mutex_unlock(&ddebug_lock); + + vpr_info("%3u debug prints in module %s\n", di->num_descs, modname); + return 0; +} + +/* helper for ddebug_dyndbg_(boot|module)_param_cb */ +static int ddebug_dyndbg_param_cb(char *param, char *val, + const char *modname, int on_err) +{ + char *sep; + + sep = strchr(param, '.'); + if (sep) { + /* needed only for ddebug_dyndbg_boot_param_cb */ + *sep = '\0'; + modname = param; + param = sep + 1; + } + if (strcmp(param, "dyndbg")) + return on_err; /* determined by caller */ + + ddebug_exec_queries((val ? val : "+p"), modname); + + return 0; /* query failure shouldn't stop module load */ +} + +/* handle both dyndbg and $module.dyndbg params at boot */ +static int ddebug_dyndbg_boot_param_cb(char *param, char *val, + const char *unused, void *arg) +{ + vpr_info("%s=\"%s\"\n", param, val); + return ddebug_dyndbg_param_cb(param, val, NULL, 0); +} + +/* + * modprobe foo finds foo.params in boot-args, strips "foo.", and + * passes them to load_module(). This callback gets unknown params, + * processes dyndbg params, rejects others. + */ +int ddebug_dyndbg_module_param_cb(char *param, char *val, const char *module) +{ + vpr_info("module: %s %s=\"%s\"\n", module, param, val); + return ddebug_dyndbg_param_cb(param, val, module, -ENOENT); +} + +static void ddebug_table_free(struct ddebug_table *dt) +{ + list_del_init(&dt->link); + kfree(dt); +} + +#ifdef CONFIG_MODULES + +/* + * Called in response to a module being unloaded. Removes + * any ddebug_table's which point at the module. + */ +static int ddebug_remove_module(const char *mod_name) +{ + struct ddebug_table *dt, *nextdt; + int ret = -ENOENT; + + mutex_lock(&ddebug_lock); + list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) { + if (dt->mod_name == mod_name) { + ddebug_table_free(dt); + ret = 0; + break; + } + } + mutex_unlock(&ddebug_lock); + if (!ret) + v2pr_info("removed module \"%s\"\n", mod_name); + return ret; +} + +static int ddebug_module_notify(struct notifier_block *self, unsigned long val, + void *data) +{ + struct module *mod = data; + int ret = 0; + + switch (val) { + case MODULE_STATE_COMING: + ret = ddebug_add_module(&mod->dyndbg_info, mod->name); + if (ret) + WARN(1, "Failed to allocate memory: dyndbg may not work properly.\n"); + break; + case MODULE_STATE_GOING: + ddebug_remove_module(mod->name); + break; + } + + return notifier_from_errno(ret); +} + +static struct notifier_block ddebug_module_nb = { + .notifier_call = ddebug_module_notify, + .priority = 0, /* dynamic debug depends on jump label */ +}; + +#endif /* CONFIG_MODULES */ + +static void ddebug_remove_all_tables(void) +{ + mutex_lock(&ddebug_lock); + while (!list_empty(&ddebug_tables)) { + struct ddebug_table *dt = list_entry(ddebug_tables.next, + struct ddebug_table, + link); + ddebug_table_free(dt); + } + mutex_unlock(&ddebug_lock); +} + +static __initdata int ddebug_init_success; + +static int __init dynamic_debug_init_control(void) +{ + struct proc_dir_entry *procfs_dir; + struct dentry *debugfs_dir; + + if (!ddebug_init_success) + return -ENODEV; + + /* Create the control file in debugfs if it is enabled */ + if (debugfs_initialized()) { + debugfs_dir = debugfs_create_dir("dynamic_debug", NULL); + debugfs_create_file("control", 0644, debugfs_dir, NULL, + &ddebug_proc_fops); + } + + /* Also create the control file in procfs */ + procfs_dir = proc_mkdir("dynamic_debug", NULL); + if (procfs_dir) + proc_create("control", 0644, procfs_dir, &proc_fops); + + return 0; +} + +static int __init dynamic_debug_init(void) +{ + struct _ddebug *iter, *iter_mod_start; + int ret, i, mod_sites, mod_ct; + const char *modname; + char *cmdline; + + struct _ddebug_info di = { + .descs = __start___dyndbg, + .classes = __start___dyndbg_classes, + .num_descs = __stop___dyndbg - __start___dyndbg, + .num_classes = __stop___dyndbg_classes - __start___dyndbg_classes, + }; + +#ifdef CONFIG_MODULES + ret = register_module_notifier(&ddebug_module_nb); + if (ret) { + pr_warn("Failed to register dynamic debug module notifier\n"); + return ret; + } +#endif /* CONFIG_MODULES */ + + if (&__start___dyndbg == &__stop___dyndbg) { + if (IS_ENABLED(CONFIG_DYNAMIC_DEBUG)) { + pr_warn("_ddebug table is empty in a CONFIG_DYNAMIC_DEBUG build\n"); + return 1; + } + pr_info("Ignore empty _ddebug table in a CONFIG_DYNAMIC_DEBUG_CORE build\n"); + ddebug_init_success = 1; + return 0; + } + + iter = iter_mod_start = __start___dyndbg; + modname = iter->modname; + i = mod_sites = mod_ct = 0; + + for (; iter < __stop___dyndbg; iter++, i++, mod_sites++) { + + if (strcmp(modname, iter->modname)) { + mod_ct++; + di.num_descs = mod_sites; + di.descs = iter_mod_start; + ret = ddebug_add_module(&di, modname); + if (ret) + goto out_err; + + mod_sites = 0; + modname = iter->modname; + iter_mod_start = iter; + } + } + di.num_descs = mod_sites; + di.descs = iter_mod_start; + ret = ddebug_add_module(&di, modname); + if (ret) + goto out_err; + + ddebug_init_success = 1; + vpr_info("%d prdebugs in %d modules, %d KiB in ddebug tables, %d kiB in __dyndbg section\n", + i, mod_ct, (int)((mod_ct * sizeof(struct ddebug_table)) >> 10), + (int)((i * sizeof(struct _ddebug)) >> 10)); + + if (di.num_classes) + v2pr_info(" %d builtin ddebug class-maps\n", di.num_classes); + + /* now that ddebug tables are loaded, process all boot args + * again to find and activate queries given in dyndbg params. + * While this has already been done for known boot params, it + * ignored the unknown ones (dyndbg in particular). Reusing + * parse_args avoids ad-hoc parsing. This will also attempt + * to activate queries for not-yet-loaded modules, which is + * slightly noisy if verbose, but harmless. + */ + cmdline = kstrdup(saved_command_line, GFP_KERNEL); + parse_args("dyndbg params", cmdline, NULL, + 0, 0, 0, NULL, &ddebug_dyndbg_boot_param_cb); + kfree(cmdline); + return 0; + +out_err: + ddebug_remove_all_tables(); + return 0; +} +/* Allow early initialization for boot messages via boot param */ +early_initcall(dynamic_debug_init); + +/* Debugfs setup must be done later */ +fs_initcall(dynamic_debug_init_control); -- cgit v1.3.1