From 95f7f15461fa482a05237669507b4c9b06865b73 Mon Sep 17 00:00:00 2001
From: Sumit Garg <sumit.garg@linaro.org>
Date: Wed, 14 Jul 2021 11:26:20 +0530
Subject: kdb: Get rid of custom debug heap allocator

Currently the only user for debug heap is kdbnearsym() which can be
modified to rather use statically allocated buffer for symbol name as
per it's current usage. So do that and hence remove custom debug heap
allocator.

Note that this change puts a restriction on kdbnearsym() callers to
carefully use shared namebuf such that a caller should consume the symbol
returned immediately prior to another call to fetch a different symbol.

Also, this change uses standard KSYM_NAME_LEN macro for namebuf
allocation instead of local variable: knt1_size which should avoid any
conflicts caused by changes to KSYM_NAME_LEN macro value.

This change has been tested using kgdbtest on arm64 which doesn't show
any regressions.

Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20210714055620.369915-1-sumit.garg@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
---
 kernel/debug/kdb/kdb_debugger.c |   1 -
 kernel/debug/kdb/kdb_private.h  |   5 -
 kernel/debug/kdb/kdb_support.c  | 329 ++++------------------------------------
 3 files changed, 28 insertions(+), 307 deletions(-)

diff --git a/kernel/debug/kdb/kdb_debugger.c b/kernel/debug/kdb/kdb_debugger.c
index 0220afda3200..e91fc3e4edd5 100644
--- a/kernel/debug/kdb/kdb_debugger.c
+++ b/kernel/debug/kdb/kdb_debugger.c
@@ -140,7 +140,6 @@ int kdb_stub(struct kgdb_state *ks)
 	 */
 	kdb_common_deinit_state();
 	KDB_STATE_CLEAR(PAGER);
-	kdbnearsym_cleanup();
 	if (error == KDB_CMD_KGDB) {
 		if (KDB_STATE(DOING_KGDB))
 			KDB_STATE_CLEAR(DOING_KGDB);
diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h
index 170c69aedebb..8dbc840113c9 100644
--- a/kernel/debug/kdb/kdb_private.h
+++ b/kernel/debug/kdb/kdb_private.h
@@ -109,7 +109,6 @@ extern int kdbgetaddrarg(int, const char **, int*, unsigned long *,
 			 long *, char **);
 extern int kdbgetsymval(const char *, kdb_symtab_t *);
 extern int kdbnearsym(unsigned long, kdb_symtab_t *);
-extern void kdbnearsym_cleanup(void);
 extern char *kdb_strdup(const char *str, gfp_t type);
 extern void kdb_symbol_print(unsigned long, const kdb_symtab_t *, unsigned int);
 
@@ -233,10 +232,6 @@ extern struct task_struct *kdb_curr_task(int);
 
 #define GFP_KDB (in_dbg_master() ? GFP_ATOMIC : GFP_KERNEL)
 
-extern void *debug_kmalloc(size_t size, gfp_t flags);
-extern void debug_kfree(void *);
-extern void debug_kusage(void);
-
 extern struct task_struct *kdb_current_task;
 extern struct pt_regs *kdb_current_regs;
 
diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c
index 9f50d22d68e6..c605b17b2a0d 100644
--- a/kernel/debug/kdb/kdb_support.c
+++ b/kernel/debug/kdb/kdb_support.c
@@ -52,48 +52,48 @@ int kdbgetsymval(const char *symname, kdb_symtab_t *symtab)
 }
 EXPORT_SYMBOL(kdbgetsymval);
 
-static char *kdb_name_table[100];	/* arbitrary size */
-
-/*
- * kdbnearsym -	Return the name of the symbol with the nearest address
- *	less than 'addr'.
+/**
+ * kdbnearsym() - Return the name of the symbol with the nearest address
+ *                less than @addr.
+ * @addr: Address to check for near symbol
+ * @symtab: Structure to receive results
  *
- * Parameters:
- *	addr	Address to check for symbol near
- *	symtab  Structure to receive results
- * Returns:
- *	0	No sections contain this address, symtab zero filled
- *	1	Address mapped to module/symbol/section, data in symtab
- * Remarks:
- *	2.6 kallsyms has a "feature" where it unpacks the name into a
- *	string.  If that string is reused before the caller expects it
- *	then the caller sees its string change without warning.  To
- *	avoid cluttering up the main kdb code with lots of kdb_strdup,
- *	tests and kfree calls, kdbnearsym maintains an LRU list of the
- *	last few unique strings.  The list is sized large enough to
- *	hold active strings, no kdb caller of kdbnearsym makes more
- *	than ~20 later calls before using a saved value.
+ * WARNING: This function may return a pointer to a single statically
+ * allocated buffer (namebuf). kdb's unusual calling context (single
+ * threaded, all other CPUs halted) provides us sufficient locking for
+ * this to be safe. The only constraint imposed by the static buffer is
+ * that the caller must consume any previous reply prior to another call
+ * to lookup a new symbol.
+ *
+ * Note that, strictly speaking, some architectures may re-enter the kdb
+ * trap if the system turns out to be very badly damaged and this breaks
+ * the single-threaded assumption above. In these circumstances successful
+ * continuation and exit from the inner trap is unlikely to work and any
+ * user attempting this receives a prominent warning before being allowed
+ * to progress. In these circumstances we remain memory safe because
+ * namebuf[KSYM_NAME_LEN-1] will never change from '\0' although we do
+ * tolerate the possibility of garbled symbol display from the outer kdb
+ * trap.
+ *
+ * Return:
+ * * 0 - No sections contain this address, symtab zero filled
+ * * 1 - Address mapped to module/symbol/section, data in symtab
  */
 int kdbnearsym(unsigned long addr, kdb_symtab_t *symtab)
 {
 	int ret = 0;
 	unsigned long symbolsize = 0;
 	unsigned long offset = 0;
-#define knt1_size 128		/* must be >= kallsyms table size */
-	char *knt1 = NULL;
+	static char namebuf[KSYM_NAME_LEN];
 
 	kdb_dbg_printf(AR, "addr=0x%lx, symtab=%px\n", addr, symtab);
 	memset(symtab, 0, sizeof(*symtab));
 
 	if (addr < 4096)
 		goto out;
-	knt1 = debug_kmalloc(knt1_size, GFP_ATOMIC);
-	if (!knt1) {
-		kdb_func_printf("addr=0x%lx cannot kmalloc knt1\n", addr);
-		goto out;
-	}
+
 	symtab->sym_name = kallsyms_lookup(addr, &symbolsize , &offset,
-				(char **)(&symtab->mod_name), knt1);
+				(char **)(&symtab->mod_name), namebuf);
 	if (offset > 8*1024*1024) {
 		symtab->sym_name = NULL;
 		addr = offset = symbolsize = 0;
@@ -102,63 +102,14 @@ int kdbnearsym(unsigned long addr, kdb_symtab_t *symtab)
 	symtab->sym_end = symtab->sym_start + symbolsize;
 	ret = symtab->sym_name != NULL && *(symtab->sym_name) != '\0';
 
-	if (ret) {
-		int i;
-		/* Another 2.6 kallsyms "feature".  Sometimes the sym_name is
-		 * set but the buffer passed into kallsyms_lookup is not used,
-		 * so it contains garbage.  The caller has to work out which
-		 * buffer needs to be saved.
-		 *
-		 * What was Rusty smoking when he wrote that code?
-		 */
-		if (symtab->sym_name != knt1) {
-			strncpy(knt1, symtab->sym_name, knt1_size);
-			knt1[knt1_size-1] = '\0';
-		}
-		for (i = 0; i < ARRAY_SIZE(kdb_name_table); ++i) {
-			if (kdb_name_table[i] &&
-			    strcmp(kdb_name_table[i], knt1) == 0)
-				break;
-		}
-		if (i >= ARRAY_SIZE(kdb_name_table)) {
-			debug_kfree(kdb_name_table[0]);
-			memmove(kdb_name_table, kdb_name_table+1,
-			       sizeof(kdb_name_table[0]) *
-			       (ARRAY_SIZE(kdb_name_table)-1));
-		} else {
-			debug_kfree(knt1);
-			knt1 = kdb_name_table[i];
-			memmove(kdb_name_table+i, kdb_name_table+i+1,
-			       sizeof(kdb_name_table[0]) *
-			       (ARRAY_SIZE(kdb_name_table)-i-1));
-		}
-		i = ARRAY_SIZE(kdb_name_table) - 1;
-		kdb_name_table[i] = knt1;
-		symtab->sym_name = kdb_name_table[i];
-		knt1 = NULL;
-	}
-
 	if (symtab->mod_name == NULL)
 		symtab->mod_name = "kernel";
 	kdb_dbg_printf(AR, "returns %d symtab->sym_start=0x%lx, symtab->mod_name=%px, symtab->sym_name=%px (%s)\n",
 		       ret, symtab->sym_start, symtab->mod_name, symtab->sym_name, symtab->sym_name);
-
 out:
-	debug_kfree(knt1);
 	return ret;
 }
 
-void kdbnearsym_cleanup(void)
-{
-	int i;
-	for (i = 0; i < ARRAY_SIZE(kdb_name_table); ++i) {
-		if (kdb_name_table[i]) {
-			debug_kfree(kdb_name_table[i]);
-			kdb_name_table[i] = NULL;
-		}
-	}
-}
-
 static char ks_namebuf[KSYM_NAME_LEN+1], ks_namebuf_prev[KSYM_NAME_LEN+1];
 
 /*
@@ -656,230 +607,6 @@ unsigned long kdb_task_state(const struct task_struct *p, unsigned long mask)
 	return (mask & kdb_task_state_string(state)) != 0;
 }
 
-/* Last ditch allocator for debugging, so we can still debug even when
- * the GFP_ATOMIC pool has been exhausted.  The algorithms are tuned
- * for space usage, not for speed.  One smallish memory pool, the free
- * chain is always in ascending address order to allow coalescing,
- * allocations are done in brute force best fit.
- */
-
-struct debug_alloc_header {
-	u32 next;	/* offset of next header from start of pool */
-	u32 size;
-	void *caller;
-};
-
-/* The memory returned by this allocator must be aligned, which means
- * so must the header size.  Do not assume that sizeof(struct
- * debug_alloc_header) is a multiple of the alignment, explicitly
- * calculate the overhead of this header, including the alignment.
- * The rest of this code must not use sizeof() on any header or
- * pointer to a header.
- */
-#define dah_align 8
-#define dah_overhead ALIGN(sizeof(struct debug_alloc_header), dah_align)
-
-static u64 debug_alloc_pool_aligned[256*1024/dah_align];	/* 256K pool */
-static char *debug_alloc_pool = (char *)debug_alloc_pool_aligned;
-static u32 dah_first, dah_first_call = 1, dah_used, dah_used_max;
-
-/* Locking is awkward.  The debug code is called from all contexts,
- * including non maskable interrupts.  A normal spinlock is not safe
- * in NMI context.  Try to get the debug allocator lock, if it cannot
- * be obtained after a second then give up.  If the lock could not be
- * previously obtained on this cpu then only try once.
- *
- * sparse has no annotation for "this function _sometimes_ acquires a
- * lock", so fudge the acquire/release notation.
- */
-static DEFINE_SPINLOCK(dap_lock);
-static int get_dap_lock(void)
-	__acquires(dap_lock)
-{
-	static int dap_locked = -1;
-	int count;
-	if (dap_locked == smp_processor_id())
-		count = 1;
-	else
-		count = 1000;
-	while (1) {
-		if (spin_trylock(&dap_lock)) {
-			dap_locked = -1;
-			return 1;
-		}
-		if (!count--)
-			break;
-		udelay(1000);
-	}
-	dap_locked = smp_processor_id();
-	__acquire(dap_lock);
-	return 0;
-}
-
-void *debug_kmalloc(size_t size, gfp_t flags)
-{
-	unsigned int rem, h_offset;
-	struct debug_alloc_header *best, *bestprev, *prev, *h;
-	void *p = NULL;
-	if (!get_dap_lock()) {
-		__release(dap_lock);	/* we never actually got it */
-		return NULL;
-	}
-	h = (struct debug_alloc_header *)(debug_alloc_pool + dah_first);
-	if (dah_first_call) {
-		h->size = sizeof(debug_alloc_pool_aligned) - dah_overhead;
-		dah_first_call = 0;
-	}
-	size = ALIGN(size, dah_align);
-	prev = best = bestprev = NULL;
-	while (1) {
-		if (h->size >= size && (!best || h->size < best->size)) {
-			best = h;
-			bestprev = prev;
-			if (h->size == size)
-				break;
-		}
-		if (!h->next)
-			break;
-		prev = h;
-		h = (struct debug_alloc_header *)(debug_alloc_pool + h->next);
-	}
-	if (!best)
-		goto out;
-	rem = best->size - size;
-	/* The pool must always contain at least one header */
-	if (best->next == 0 && bestprev == NULL && rem < dah_overhead)
-		goto out;
-	if (rem >= dah_overhead) {
-		best->size = size;
-		h_offset = ((char *)best - debug_alloc_pool) +
-			   dah_overhead + best->size;
-		h = (struct debug_alloc_header *)(debug_alloc_pool + h_offset);
-		h->size = rem - dah_overhead;
-		h->next = best->next;
-	} else
-		h_offset = best->next;
-	best->caller = __builtin_return_address(0);
-	dah_used += best->size;
-	dah_used_max = max(dah_used, dah_used_max);
-	if (bestprev)
-		bestprev->next = h_offset;
-	else
-		dah_first = h_offset;
-	p = (char *)best + dah_overhead;
-	memset(p, POISON_INUSE, best->size - 1);
-	*((char *)p + best->size - 1) = POISON_END;
-out:
-	spin_unlock(&dap_lock);
-	return p;
-}
-
-void debug_kfree(void *p)
-{
-	struct debug_alloc_header *h;
-	unsigned int h_offset;
-	if (!p)
-		return;
-	if ((char *)p < debug_alloc_pool ||
-	    (char *)p >= debug_alloc_pool + sizeof(debug_alloc_pool_aligned)) {
-		kfree(p);
-		return;
-	}
-	if (!get_dap_lock()) {
-		__release(dap_lock);	/* we never actually got it */
-		return;		/* memory leak, cannot be helped */
-	}
-	h = (struct debug_alloc_header *)((char *)p - dah_overhead);
-	memset(p, POISON_FREE, h->size - 1);
-	*((char *)p + h->size - 1) = POISON_END;
-	h->caller = NULL;
-	dah_used -= h->size;
-	h_offset = (char *)h - debug_alloc_pool;
-	if (h_offset < dah_first) {
-		h->next = dah_first;
-		dah_first = h_offset;
-	} else {
-		struct debug_alloc_header *prev;
-		unsigned int prev_offset;
-		prev = (struct debug_alloc_header *)(debug_alloc_pool +
-						     dah_first);
-		while (1) {
-			if (!prev->next || prev->next > h_offset)
-				break;
-			prev = (struct debug_alloc_header *)
-				(debug_alloc_pool + prev->next);
-		}
-		prev_offset = (char *)prev - debug_alloc_pool;
-		if (prev_offset + dah_overhead + prev->size == h_offset) {
-			prev->size += dah_overhead + h->size;
-			memset(h, POISON_FREE, dah_overhead - 1);
-			*((char *)h + dah_overhead - 1) = POISON_END;
-			h = prev;
-			h_offset = prev_offset;
-		} else {
-			h->next = prev->next;
-			prev->next = h_offset;
-		}
-	}
-	if (h_offset + dah_overhead + h->size == h->next) {
-		struct debug_alloc_header *next;
-		next = (struct debug_alloc_header *)
-			(debug_alloc_pool + h->next);
-		h->size += dah_overhead + next->size;
-		h->next = next->next;
-		memset(next, POISON_FREE, dah_overhead - 1);
-		*((char *)next + dah_overhead - 1) = POISON_END;
-	}
-	spin_unlock(&dap_lock);
-}
-
-void debug_kusage(void)
-{
-	struct debug_alloc_header *h_free, *h_used;
-#ifdef	CONFIG_IA64
-	/* FIXME: using dah for ia64 unwind always results in a memory leak.
-	 * Fix that memory leak first, then set debug_kusage_one_time = 1 for
-	 * all architectures.
-	 */
-	static int debug_kusage_one_time;
-#else
-	static int debug_kusage_one_time = 1;
-#endif
-	if (!get_dap_lock()) {
-		__release(dap_lock);	/* we never actually got it */
-		return;
-	}
-	h_free = (struct debug_alloc_header *)(debug_alloc_pool + dah_first);
-	if (dah_first == 0 &&
-	    (h_free->size == sizeof(debug_alloc_pool_aligned) - dah_overhead ||
-	     dah_first_call))
-		goto out;
-	if (!debug_kusage_one_time)
-		goto out;
-	debug_kusage_one_time = 0;
-	kdb_func_printf("debug_kmalloc memory leak dah_first %d\n", dah_first);
-	if (dah_first) {
-		h_used = (struct debug_alloc_header *)debug_alloc_pool;
-		kdb_func_printf("h_used %px size %d\n", h_used, h_used->size);
-	}
-	do {
-		h_used = (struct debug_alloc_header *)
-			  ((char *)h_free + dah_overhead + h_free->size);
-		kdb_func_printf("h_used %px size %d caller %px\n",
-				h_used, h_used->size, h_used->caller);
-		h_free = (struct debug_alloc_header *)
-			  (debug_alloc_pool + h_free->next);
-	} while (h_free->next);
-	h_used = (struct debug_alloc_header *)
-		  ((char *)h_free + dah_overhead + h_free->size);
-	if ((char *)h_used - debug_alloc_pool !=
-	    sizeof(debug_alloc_pool_aligned))
-		kdb_func_printf("h_used %px size %d caller %px\n",
-				h_used, h_used->size, h_used->caller);
-out:
-	spin_unlock(&dap_lock);
-}
-
 /* Maintain a small stack of kdb_flags to allow recursion without disturbing
  * the global kdb state.
  */
-- 
cgit 


From b39cded834154cf54442489b56b33d047edd6d8f Mon Sep 17 00:00:00 2001
From: Sumit Garg <sumit.garg@linaro.org>
Date: Mon, 12 Jul 2021 19:16:17 +0530
Subject: kdb: Rename struct defcmd_set to struct kdb_macro

Rename struct defcmd_set to struct kdb_macro as that sounds more
appropriate given its purpose.

Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20210712134620.276667-2-sumit.garg@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
---
 kernel/debug/kdb/kdb_main.c | 40 ++++++++++++++++++++--------------------
 1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index d8ee5647b732..5cf9867fa118 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -654,7 +654,7 @@ static void kdb_cmderror(int diag)
  * Returns:
  *	zero for success, a kdb diagnostic if error
  */
-struct defcmd_set {
+struct kdb_macro {
 	int count;
 	bool usable;
 	char *name;
@@ -662,8 +662,8 @@ struct defcmd_set {
 	char *help;
 	char **command;
 };
-static struct defcmd_set *defcmd_set;
-static int defcmd_set_count;
+static struct kdb_macro *kdb_macro;
+static int kdb_macro_count;
 static bool defcmd_in_progress;
 
 /* Forward references */
@@ -671,7 +671,7 @@ static int kdb_exec_defcmd(int argc, const char **argv);
 
 static int kdb_defcmd2(const char *cmdstr, const char *argv0)
 {
-	struct defcmd_set *s = defcmd_set + defcmd_set_count - 1;
+	struct kdb_macro *s = kdb_macro + kdb_macro_count - 1;
 	char **save_command = s->command;
 	if (strcmp(argv0, "endefcmd") == 0) {
 		defcmd_in_progress = false;
@@ -704,7 +704,7 @@ static int kdb_defcmd2(const char *cmdstr, const char *argv0)
 
 static int kdb_defcmd(int argc, const char **argv)
 {
-	struct defcmd_set *save_defcmd_set = defcmd_set, *s;
+	struct kdb_macro *save_kdb_macro = kdb_macro, *s;
 	if (defcmd_in_progress) {
 		kdb_printf("kdb: nested defcmd detected, assuming missing "
 			   "endefcmd\n");
@@ -712,7 +712,7 @@ static int kdb_defcmd(int argc, const char **argv)
 	}
 	if (argc == 0) {
 		int i;
-		for (s = defcmd_set; s < defcmd_set + defcmd_set_count; ++s) {
+		for (s = kdb_macro; s < kdb_macro + kdb_macro_count; ++s) {
 			kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->name,
 				   s->usage, s->help);
 			for (i = 0; i < s->count; ++i)
@@ -727,13 +727,13 @@ static int kdb_defcmd(int argc, const char **argv)
 		kdb_printf("Command only available during kdb_init()\n");
 		return KDB_NOTIMP;
 	}
-	defcmd_set = kmalloc_array(defcmd_set_count + 1, sizeof(*defcmd_set),
-				   GFP_KDB);
-	if (!defcmd_set)
+	kdb_macro = kmalloc_array(kdb_macro_count + 1, sizeof(*kdb_macro),
+				  GFP_KDB);
+	if (!kdb_macro)
 		goto fail_defcmd;
-	memcpy(defcmd_set, save_defcmd_set,
-	       defcmd_set_count * sizeof(*defcmd_set));
-	s = defcmd_set + defcmd_set_count;
+	memcpy(kdb_macro, save_kdb_macro,
+	       kdb_macro_count * sizeof(*kdb_macro));
+	s = kdb_macro + kdb_macro_count;
 	memset(s, 0, sizeof(*s));
 	s->usable = true;
 	s->name = kdb_strdup(argv[1], GFP_KDB);
@@ -753,19 +753,19 @@ static int kdb_defcmd(int argc, const char **argv)
 		strcpy(s->help, argv[3]+1);
 		s->help[strlen(s->help)-1] = '\0';
 	}
-	++defcmd_set_count;
+	++kdb_macro_count;
 	defcmd_in_progress = true;
-	kfree(save_defcmd_set);
+	kfree(save_kdb_macro);
 	return 0;
 fail_help:
 	kfree(s->usage);
 fail_usage:
 	kfree(s->name);
 fail_name:
-	kfree(defcmd_set);
+	kfree(kdb_macro);
 fail_defcmd:
-	kdb_printf("Could not allocate new defcmd_set entry for %s\n", argv[1]);
-	defcmd_set = save_defcmd_set;
+	kdb_printf("Could not allocate new kdb_macro entry for %s\n", argv[1]);
+	kdb_macro = save_kdb_macro;
 	return KDB_NOTIMP;
 }
 
@@ -781,14 +781,14 @@ fail_defcmd:
 static int kdb_exec_defcmd(int argc, const char **argv)
 {
 	int i, ret;
-	struct defcmd_set *s;
+	struct kdb_macro *s;
 	if (argc != 0)
 		return KDB_ARGCOUNT;
-	for (s = defcmd_set, i = 0; i < defcmd_set_count; ++i, ++s) {
+	for (s = kdb_macro, i = 0; i < kdb_macro_count; ++i, ++s) {
 		if (strcmp(s->name, argv[0]) == 0)
 			break;
 	}
-	if (i == defcmd_set_count) {
+	if (i == kdb_macro_count) {
 		kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
 			   argv[0]);
 		return KDB_NOTIMP;
-- 
cgit 


From c25abcd625505f53b72dc156bac32b5120826742 Mon Sep 17 00:00:00 2001
From: Sumit Garg <sumit.garg@linaro.org>
Date: Mon, 12 Jul 2021 19:16:18 +0530
Subject: kdb: Get rid of redundant kdb_register_flags()

Commit e4f291b3f7bb ("kdb: Simplify kdb commands registration")
allowed registration of pre-allocated kdb commands with pointer to
struct kdbtab_t. Lets switch other users as well to register pre-
allocated kdb commands via:
- Changing prototype for kdb_register() to pass a pointer to struct
  kdbtab_t instead.
- Embed kdbtab_t structure in kdb_macro_t rather than individual params.

With these changes kdb_register_flags() becomes redundant and hence
removed. Also, since we have switched all users to register
pre-allocated commands, "is_dynamic" flag in struct kdbtab_t becomes
redundant and hence removed as well.

Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20210712134620.276667-3-sumit.garg@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
---
 include/linux/kdb.h            |  27 ++++---
 kernel/debug/kdb/kdb_main.c    | 167 +++++++++++++----------------------------
 kernel/debug/kdb/kdb_private.h |  13 ----
 kernel/trace/trace_kdb.c       |  12 ++-
 samples/kdb/kdb_hello.c        |  20 +++--
 5 files changed, 88 insertions(+), 151 deletions(-)

diff --git a/include/linux/kdb.h b/include/linux/kdb.h
index 0125a677b67f..de858edfb3b8 100644
--- a/include/linux/kdb.h
+++ b/include/linux/kdb.h
@@ -13,6 +13,8 @@
  * Copyright (C) 2009 Jason Wessel <jason.wessel@windriver.com>
  */
 
+#include <linux/list.h>
+
 /* Shifted versions of the command enable bits are be used if the command
  * has no arguments (see kdb_check_flags). This allows commands, such as
  * go, to have different permissions depending upon whether it is called
@@ -64,6 +66,17 @@ typedef enum {
 
 typedef int (*kdb_func_t)(int, const char **);
 
+/* The KDB shell command table */
+typedef struct _kdbtab {
+	char    *cmd_name;		/* Command name */
+	kdb_func_t cmd_func;		/* Function to execute command */
+	char    *cmd_usage;		/* Usage String for this command */
+	char    *cmd_help;		/* Help message for this command */
+	short    cmd_minlen;		/* Minimum legal # cmd chars required */
+	kdb_cmdflags_t cmd_flags;	/* Command behaviour flags */
+	struct list_head list_node;	/* Command list */
+} kdbtab_t;
+
 #ifdef	CONFIG_KGDB_KDB
 #include <linux/init.h>
 #include <linux/sched.h>
@@ -193,19 +206,13 @@ static inline const char *kdb_walk_kallsyms(loff_t *pos)
 #endif /* ! CONFIG_KALLSYMS */
 
 /* Dynamic kdb shell command registration */
-extern int kdb_register(char *, kdb_func_t, char *, char *, short);
-extern int kdb_register_flags(char *, kdb_func_t, char *, char *,
-			      short, kdb_cmdflags_t);
-extern int kdb_unregister(char *);
+extern int kdb_register(kdbtab_t *cmd);
+extern void kdb_unregister(kdbtab_t *cmd);
 #else /* ! CONFIG_KGDB_KDB */
 static inline __printf(1, 2) int kdb_printf(const char *fmt, ...) { return 0; }
 static inline void kdb_init(int level) {}
-static inline int kdb_register(char *cmd, kdb_func_t func, char *usage,
-			       char *help, short minlen) { return 0; }
-static inline int kdb_register_flags(char *cmd, kdb_func_t func, char *usage,
-				     char *help, short minlen,
-				     kdb_cmdflags_t flags) { return 0; }
-static inline int kdb_unregister(char *cmd) { return 0; }
+static inline int kdb_register(kdbtab_t *cmd) { return 0; }
+static inline void kdb_unregister(kdbtab_t *cmd) {}
 #endif	/* CONFIG_KGDB_KDB */
 enum {
 	KDB_NOT_INITIALIZED,
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 5cf9867fa118..b2880fad26d4 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -33,7 +33,6 @@
 #include <linux/kallsyms.h>
 #include <linux/kgdb.h>
 #include <linux/kdb.h>
-#include <linux/list.h>
 #include <linux/notifier.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
@@ -657,9 +656,7 @@ static void kdb_cmderror(int diag)
 struct kdb_macro {
 	int count;
 	bool usable;
-	char *name;
-	char *usage;
-	char *help;
+	kdbtab_t cmd;
 	char **command;
 };
 static struct kdb_macro *kdb_macro;
@@ -678,13 +675,7 @@ static int kdb_defcmd2(const char *cmdstr, const char *argv0)
 		if (!s->count)
 			s->usable = false;
 		if (s->usable)
-			/* macros are always safe because when executed each
-			 * internal command re-enters kdb_parse() and is
-			 * safety checked individually.
-			 */
-			kdb_register_flags(s->name, kdb_exec_defcmd, s->usage,
-					   s->help, 0,
-					   KDB_ENABLE_ALWAYS_SAFE);
+			kdb_register(&s->cmd);
 		return 0;
 	}
 	if (!s->usable)
@@ -705,6 +696,8 @@ static int kdb_defcmd2(const char *cmdstr, const char *argv0)
 static int kdb_defcmd(int argc, const char **argv)
 {
 	struct kdb_macro *save_kdb_macro = kdb_macro, *s;
+	kdbtab_t *mp;
+
 	if (defcmd_in_progress) {
 		kdb_printf("kdb: nested defcmd detected, assuming missing "
 			   "endefcmd\n");
@@ -713,8 +706,8 @@ static int kdb_defcmd(int argc, const char **argv)
 	if (argc == 0) {
 		int i;
 		for (s = kdb_macro; s < kdb_macro + kdb_macro_count; ++s) {
-			kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->name,
-				   s->usage, s->help);
+			kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->cmd.cmd_name,
+				   s->cmd.cmd_usage, s->cmd.cmd_help);
 			for (i = 0; i < s->count; ++i)
 				kdb_printf("%s", s->command[i]);
 			kdb_printf("endefcmd\n");
@@ -736,31 +729,36 @@ static int kdb_defcmd(int argc, const char **argv)
 	s = kdb_macro + kdb_macro_count;
 	memset(s, 0, sizeof(*s));
 	s->usable = true;
-	s->name = kdb_strdup(argv[1], GFP_KDB);
-	if (!s->name)
+
+	mp = &s->cmd;
+	mp->cmd_func = kdb_exec_defcmd;
+	mp->cmd_minlen = 0;
+	mp->cmd_flags = KDB_ENABLE_ALWAYS_SAFE;
+	mp->cmd_name = kdb_strdup(argv[1], GFP_KDB);
+	if (!mp->cmd_name)
 		goto fail_name;
-	s->usage = kdb_strdup(argv[2], GFP_KDB);
-	if (!s->usage)
+	mp->cmd_usage = kdb_strdup(argv[2], GFP_KDB);
+	if (!mp->cmd_usage)
 		goto fail_usage;
-	s->help = kdb_strdup(argv[3], GFP_KDB);
-	if (!s->help)
+	mp->cmd_help = kdb_strdup(argv[3], GFP_KDB);
+	if (!mp->cmd_help)
 		goto fail_help;
-	if (s->usage[0] == '"') {
-		strcpy(s->usage, argv[2]+1);
-		s->usage[strlen(s->usage)-1] = '\0';
+	if (mp->cmd_usage[0] == '"') {
+		strcpy(mp->cmd_usage, argv[2]+1);
+		mp->cmd_usage[strlen(mp->cmd_usage)-1] = '\0';
 	}
-	if (s->help[0] == '"') {
-		strcpy(s->help, argv[3]+1);
-		s->help[strlen(s->help)-1] = '\0';
+	if (mp->cmd_help[0] == '"') {
+		strcpy(mp->cmd_help, argv[3]+1);
+		mp->cmd_help[strlen(mp->cmd_help)-1] = '\0';
 	}
 	++kdb_macro_count;
 	defcmd_in_progress = true;
 	kfree(save_kdb_macro);
 	return 0;
 fail_help:
-	kfree(s->usage);
+	kfree(mp->cmd_usage);
 fail_usage:
-	kfree(s->name);
+	kfree(mp->cmd_name);
 fail_name:
 	kfree(kdb_macro);
 fail_defcmd:
@@ -785,7 +783,7 @@ static int kdb_exec_defcmd(int argc, const char **argv)
 	if (argc != 0)
 		return KDB_ARGCOUNT;
 	for (s = kdb_macro, i = 0; i < kdb_macro_count; ++i, ++s) {
-		if (strcmp(s->name, argv[0]) == 0)
+		if (strcmp(s->cmd.cmd_name, argv[0]) == 0)
 			break;
 	}
 	if (i == kdb_macro_count) {
@@ -797,7 +795,7 @@ static int kdb_exec_defcmd(int argc, const char **argv)
 		/* Recursive use of kdb_parse, do not use argv after
 		 * this point */
 		argv = NULL;
-		kdb_printf("[%s]kdb> %s\n", s->name, s->command[i]);
+		kdb_printf("[%s]kdb> %s\n", s->cmd.cmd_name, s->command[i]);
 		ret = kdb_parse(s->command[i]);
 		if (ret)
 			return ret;
@@ -2613,56 +2611,32 @@ static int kdb_grep_help(int argc, const char **argv)
 	return 0;
 }
 
-/*
- * kdb_register_flags - This function is used to register a kernel
- * 	debugger command.
- * Inputs:
- *	cmd	Command name
- *	func	Function to execute the command
- *	usage	A simple usage string showing arguments
- *	help	A simple help string describing command
- *	repeat	Does the command auto repeat on enter?
- * Returns:
- *	zero for success, one if a duplicate command.
+/**
+ * kdb_register() - This function is used to register a kernel debugger
+ *                  command.
+ * @cmd: pointer to kdb command
+ *
+ * Note that it's the job of the caller to keep the memory for the cmd
+ * allocated until unregister is called.
  */
-int kdb_register_flags(char *cmd,
-		       kdb_func_t func,
-		       char *usage,
-		       char *help,
-		       short minlen,
-		       kdb_cmdflags_t flags)
+int kdb_register(kdbtab_t *cmd)
 {
 	kdbtab_t *kp;
 
 	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
-		if (strcmp(kp->cmd_name, cmd) == 0) {
-			kdb_printf("Duplicate kdb command registered: "
-				"%s, func %px help %s\n", cmd, func, help);
+		if (strcmp(kp->cmd_name, cmd->cmd_name) == 0) {
+			kdb_printf("Duplicate kdb cmd: %s, func %p help %s\n",
+				   cmd->cmd_name, cmd->cmd_func, cmd->cmd_help);
 			return 1;
 		}
 	}
 
-	kp = kmalloc(sizeof(*kp), GFP_KDB);
-	if (!kp) {
-		kdb_printf("Could not allocate new kdb_command table\n");
-		return 1;
-	}
-
-	kp->cmd_name   = cmd;
-	kp->cmd_func   = func;
-	kp->cmd_usage  = usage;
-	kp->cmd_help   = help;
-	kp->cmd_minlen = minlen;
-	kp->cmd_flags  = flags;
-	kp->is_dynamic = true;
-
-	list_add_tail(&kp->list_node, &kdb_cmds_head);
-
+	list_add_tail(&cmd->list_node, &kdb_cmds_head);
 	return 0;
 }
-EXPORT_SYMBOL_GPL(kdb_register_flags);
+EXPORT_SYMBOL_GPL(kdb_register);
 
-/*
+/**
  * kdb_register_table() - This function is used to register a kdb command
  *                        table.
  * @kp: pointer to kdb command table
@@ -2676,55 +2650,15 @@ void kdb_register_table(kdbtab_t *kp, size_t len)
 	}
 }
 
-/*
- * kdb_register - Compatibility register function for commands that do
- *	not need to specify a repeat state.  Equivalent to
- *	kdb_register_flags with flags set to 0.
- * Inputs:
- *	cmd	Command name
- *	func	Function to execute the command
- *	usage	A simple usage string showing arguments
- *	help	A simple help string describing command
- * Returns:
- *	zero for success, one if a duplicate command.
- */
-int kdb_register(char *cmd,
-	     kdb_func_t func,
-	     char *usage,
-	     char *help,
-	     short minlen)
-{
-	return kdb_register_flags(cmd, func, usage, help, minlen, 0);
-}
-EXPORT_SYMBOL_GPL(kdb_register);
-
-/*
- * kdb_unregister - This function is used to unregister a kernel
- *	debugger command.  It is generally called when a module which
- *	implements kdb commands is unloaded.
- * Inputs:
- *	cmd	Command name
- * Returns:
- *	zero for success, one command not registered.
+/**
+ * kdb_unregister() - This function is used to unregister a kernel debugger
+ *                    command. It is generally called when a module which
+ *                    implements kdb command is unloaded.
+ * @cmd: pointer to kdb command
  */
-int kdb_unregister(char *cmd)
+void kdb_unregister(kdbtab_t *cmd)
 {
-	kdbtab_t *kp;
-
-	/*
-	 *  find the command.
-	 */
-	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
-		if (strcmp(kp->cmd_name, cmd) == 0) {
-			list_del(&kp->list_node);
-			if (kp->is_dynamic)
-				kfree(kp);
-			return 0;
-		}
-	}
-
-	/* Couldn't find it.  */
-	return 1;
+	list_del(&cmd->list_node);
 }
 EXPORT_SYMBOL_GPL(kdb_unregister);
 
@@ -2900,6 +2834,11 @@ static kdbtab_t maintab[] = {
 		.cmd_func = kdb_defcmd,
 		.cmd_usage = "name \"usage\" \"help\"",
 		.cmd_help = "Define a set of commands, down to endefcmd",
+		/*
+		 * Macros are always safe because when executed each
+		 * internal command re-enters kdb_parse() and is safety
+		 * checked individually.
+		 */
 		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
 	},
 	{	.cmd_name = "kill",
diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h
index 8dbc840113c9..629590084a0d 100644
--- a/kernel/debug/kdb/kdb_private.h
+++ b/kernel/debug/kdb/kdb_private.h
@@ -164,19 +164,6 @@ typedef struct _kdb_bp {
 #ifdef CONFIG_KGDB_KDB
 extern kdb_bp_t kdb_breakpoints[/* KDB_MAXBPT */];
 
-/* The KDB shell command table */
-typedef struct _kdbtab {
-	char    *cmd_name;		/* Command name */
-	kdb_func_t cmd_func;		/* Function to execute command */
-	char    *cmd_usage;		/* Usage String for this command */
-	char    *cmd_help;		/* Help message for this command */
-	short    cmd_minlen;		/* Minimum legal # command
-					 * chars required */
-	kdb_cmdflags_t cmd_flags;	/* Command behaviour flags */
-	struct list_head list_node;	/* Command list */
-	bool    is_dynamic;		/* Command table allocation type */
-} kdbtab_t;
-
 extern void kdb_register_table(kdbtab_t *kp, size_t len);
 extern int kdb_bt(int, const char **);	/* KDB display back trace */
 
diff --git a/kernel/trace/trace_kdb.c b/kernel/trace/trace_kdb.c
index 9da76104f7a2..6c4f92c79e43 100644
--- a/kernel/trace/trace_kdb.c
+++ b/kernel/trace/trace_kdb.c
@@ -147,11 +147,17 @@ static int kdb_ftdump(int argc, const char **argv)
 	return 0;
 }
 
+static kdbtab_t ftdump_cmd = {
+	.cmd_name = "ftdump",
+	.cmd_func = kdb_ftdump,
+	.cmd_usage = "[skip_#entries] [cpu]",
+	.cmd_help = "Dump ftrace log; -skip dumps last #entries",
+	.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
+};
+
 static __init int kdb_ftrace_register(void)
 {
-	kdb_register_flags("ftdump", kdb_ftdump, "[skip_#entries] [cpu]",
-			    "Dump ftrace log; -skip dumps last #entries", 0,
-			    KDB_ENABLE_ALWAYS_SAFE);
+	kdb_register(&ftdump_cmd);
 	return 0;
 }
 
diff --git a/samples/kdb/kdb_hello.c b/samples/kdb/kdb_hello.c
index c1c2fa0f62c2..9ad514a6648b 100644
--- a/samples/kdb/kdb_hello.c
+++ b/samples/kdb/kdb_hello.c
@@ -28,28 +28,26 @@ static int kdb_hello_cmd(int argc, const char **argv)
 	return 0;
 }
 
+static kdbtab_t hello_cmd = {
+	.cmd_name = "hello",
+	.cmd_func = kdb_hello_cmd,
+	.cmd_usage = "[string]",
+	.cmd_help = "Say Hello World or Hello [string]",
+};
 
 static int __init kdb_hello_cmd_init(void)
 {
 	/*
 	 * Registration of a dynamically added kdb command is done with
-	 * kdb_register() with the arguments being:
-	 *   1: The name of the shell command
-	 *   2: The function that processes the command
-	 *   3: Description of the usage of any arguments
-	 *   4: Descriptive text when you run help
-	 *   5: Number of characters to complete the command
-	 *      0 == type the whole command
-	 *      1 == match both "g" and "go" for example
+	 * kdb_register().
 	 */
-	kdb_register("hello", kdb_hello_cmd, "[string]",
-		     "Say Hello World or Hello [string]", 0);
+	kdb_register(&hello_cmd);
 	return 0;
 }
 
 static void __exit kdb_hello_cmd_exit(void)
 {
-	kdb_unregister("hello");
+	kdb_unregister(&hello_cmd);
 }
 
 module_init(kdb_hello_cmd_init);
-- 
cgit 


From 9a5db530aa7d98b10c4f5104027565c98cca49e6 Mon Sep 17 00:00:00 2001
From: Sumit Garg <sumit.garg@linaro.org>
Date: Mon, 12 Jul 2021 19:16:19 +0530
Subject: kdb: Simplify kdb_defcmd macro logic

Switch to use a linked list instead of dynamic array which makes
allocation of kdb macro and traversing the kdb macro commands list
simpler.

Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20210712134620.276667-4-sumit.garg@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
---
 kernel/debug/kdb/kdb_main.c | 107 ++++++++++++++++++++++++--------------------
 1 file changed, 58 insertions(+), 49 deletions(-)

diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index b2880fad26d4..7c7a2ef834fc 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -654,13 +654,16 @@ static void kdb_cmderror(int diag)
  *	zero for success, a kdb diagnostic if error
  */
 struct kdb_macro {
-	int count;
-	bool usable;
-	kdbtab_t cmd;
-	char **command;
+	kdbtab_t cmd;			/* Macro command */
+	struct list_head statements;	/* Associated statement list */
 };
+
+struct kdb_macro_statement {
+	char *statement;		/* Statement text */
+	struct list_head list_node;	/* Statement list node */
+};
+
 static struct kdb_macro *kdb_macro;
-static int kdb_macro_count;
 static bool defcmd_in_progress;
 
 /* Forward references */
@@ -668,34 +671,33 @@ static int kdb_exec_defcmd(int argc, const char **argv);
 
 static int kdb_defcmd2(const char *cmdstr, const char *argv0)
 {
-	struct kdb_macro *s = kdb_macro + kdb_macro_count - 1;
-	char **save_command = s->command;
+	struct kdb_macro_statement *kms;
+
+	if (!kdb_macro)
+		return KDB_NOTIMP;
+
 	if (strcmp(argv0, "endefcmd") == 0) {
 		defcmd_in_progress = false;
-		if (!s->count)
-			s->usable = false;
-		if (s->usable)
-			kdb_register(&s->cmd);
+		if (!list_empty(&kdb_macro->statements))
+			kdb_register(&kdb_macro->cmd);
 		return 0;
 	}
-	if (!s->usable)
-		return KDB_NOTIMP;
-	s->command = kcalloc(s->count + 1, sizeof(*(s->command)), GFP_KDB);
-	if (!s->command) {
-		kdb_printf("Could not allocate new kdb_defcmd table for %s\n",
+
+	kms = kmalloc(sizeof(*kms), GFP_KDB);
+	if (!kms) {
+		kdb_printf("Could not allocate new kdb macro command: %s\n",
 			   cmdstr);
-		s->usable = false;
 		return KDB_NOTIMP;
 	}
-	memcpy(s->command, save_command, s->count * sizeof(*(s->command)));
-	s->command[s->count++] = kdb_strdup(cmdstr, GFP_KDB);
-	kfree(save_command);
+
+	kms->statement = kdb_strdup(cmdstr, GFP_KDB);
+	list_add_tail(&kms->list_node, &kdb_macro->statements);
+
 	return 0;
 }
 
 static int kdb_defcmd(int argc, const char **argv)
 {
-	struct kdb_macro *save_kdb_macro = kdb_macro, *s;
 	kdbtab_t *mp;
 
 	if (defcmd_in_progress) {
@@ -704,13 +706,21 @@ static int kdb_defcmd(int argc, const char **argv)
 		kdb_defcmd2("endefcmd", "endefcmd");
 	}
 	if (argc == 0) {
-		int i;
-		for (s = kdb_macro; s < kdb_macro + kdb_macro_count; ++s) {
-			kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->cmd.cmd_name,
-				   s->cmd.cmd_usage, s->cmd.cmd_help);
-			for (i = 0; i < s->count; ++i)
-				kdb_printf("%s", s->command[i]);
-			kdb_printf("endefcmd\n");
+		kdbtab_t *kp;
+		struct kdb_macro *kmp;
+		struct kdb_macro_statement *kms;
+
+		list_for_each_entry(kp, &kdb_cmds_head, list_node) {
+			if (kp->cmd_func == kdb_exec_defcmd) {
+				kdb_printf("defcmd %s \"%s\" \"%s\"\n",
+					   kp->cmd_name, kp->cmd_usage,
+					   kp->cmd_help);
+				kmp = container_of(kp, struct kdb_macro, cmd);
+				list_for_each_entry(kms, &kmp->statements,
+						    list_node)
+					kdb_printf("%s", kms->statement);
+				kdb_printf("endefcmd\n");
+			}
 		}
 		return 0;
 	}
@@ -720,17 +730,11 @@ static int kdb_defcmd(int argc, const char **argv)
 		kdb_printf("Command only available during kdb_init()\n");
 		return KDB_NOTIMP;
 	}
-	kdb_macro = kmalloc_array(kdb_macro_count + 1, sizeof(*kdb_macro),
-				  GFP_KDB);
+	kdb_macro = kzalloc(sizeof(*kdb_macro), GFP_KDB);
 	if (!kdb_macro)
 		goto fail_defcmd;
-	memcpy(kdb_macro, save_kdb_macro,
-	       kdb_macro_count * sizeof(*kdb_macro));
-	s = kdb_macro + kdb_macro_count;
-	memset(s, 0, sizeof(*s));
-	s->usable = true;
 
-	mp = &s->cmd;
+	mp = &kdb_macro->cmd;
 	mp->cmd_func = kdb_exec_defcmd;
 	mp->cmd_minlen = 0;
 	mp->cmd_flags = KDB_ENABLE_ALWAYS_SAFE;
@@ -751,9 +755,9 @@ static int kdb_defcmd(int argc, const char **argv)
 		strcpy(mp->cmd_help, argv[3]+1);
 		mp->cmd_help[strlen(mp->cmd_help)-1] = '\0';
 	}
-	++kdb_macro_count;
+
+	INIT_LIST_HEAD(&kdb_macro->statements);
 	defcmd_in_progress = true;
-	kfree(save_kdb_macro);
 	return 0;
 fail_help:
 	kfree(mp->cmd_usage);
@@ -763,7 +767,6 @@ fail_name:
 	kfree(kdb_macro);
 fail_defcmd:
 	kdb_printf("Could not allocate new kdb_macro entry for %s\n", argv[1]);
-	kdb_macro = save_kdb_macro;
 	return KDB_NOTIMP;
 }
 
@@ -778,25 +781,31 @@ fail_defcmd:
  */
 static int kdb_exec_defcmd(int argc, const char **argv)
 {
-	int i, ret;
-	struct kdb_macro *s;
+	int ret;
+	kdbtab_t *kp;
+	struct kdb_macro *kmp;
+	struct kdb_macro_statement *kms;
+
 	if (argc != 0)
 		return KDB_ARGCOUNT;
-	for (s = kdb_macro, i = 0; i < kdb_macro_count; ++i, ++s) {
-		if (strcmp(s->cmd.cmd_name, argv[0]) == 0)
+
+	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
+		if (strcmp(kp->cmd_name, argv[0]) == 0)
 			break;
 	}
-	if (i == kdb_macro_count) {
+	if (list_entry_is_head(kp, &kdb_cmds_head, list_node)) {
 		kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
 			   argv[0]);
 		return KDB_NOTIMP;
 	}
-	for (i = 0; i < s->count; ++i) {
-		/* Recursive use of kdb_parse, do not use argv after
-		 * this point */
+	kmp = container_of(kp, struct kdb_macro, cmd);
+	list_for_each_entry(kms, &kmp->statements, list_node) {
+		/*
+		 * Recursive use of kdb_parse, do not use argv after this point.
+		 */
 		argv = NULL;
-		kdb_printf("[%s]kdb> %s\n", s->cmd.cmd_name, s->command[i]);
-		ret = kdb_parse(s->command[i]);
+		kdb_printf("[%s]kdb> %s\n", kmp->cmd.cmd_name, kms->statement);
+		ret = kdb_parse(kms->statement);
 		if (ret)
 			return ret;
 	}
-- 
cgit 


From e868f0a3c4b9c1d7721f08b703142a876814a3f8 Mon Sep 17 00:00:00 2001
From: Sumit Garg <sumit.garg@linaro.org>
Date: Mon, 12 Jul 2021 19:16:20 +0530
Subject: kdb: Rename members of struct kdbtab_t

Remove redundant prefix "cmd_" from name of members in struct kdbtab_t
for better readibility.

Suggested-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20210712134620.276667-5-sumit.garg@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
---
 include/linux/kdb.h         |  12 +-
 kernel/debug/kdb/kdb_bp.c   |  72 ++++----
 kernel/debug/kdb/kdb_main.c | 404 ++++++++++++++++++++++----------------------
 kernel/trace/trace_kdb.c    |  10 +-
 samples/kdb/kdb_hello.c     |   8 +-
 5 files changed, 252 insertions(+), 254 deletions(-)

diff --git a/include/linux/kdb.h b/include/linux/kdb.h
index de858edfb3b8..ea0f5e580fac 100644
--- a/include/linux/kdb.h
+++ b/include/linux/kdb.h
@@ -68,12 +68,12 @@ typedef int (*kdb_func_t)(int, const char **);
 
 /* The KDB shell command table */
 typedef struct _kdbtab {
-	char    *cmd_name;		/* Command name */
-	kdb_func_t cmd_func;		/* Function to execute command */
-	char    *cmd_usage;		/* Usage String for this command */
-	char    *cmd_help;		/* Help message for this command */
-	short    cmd_minlen;		/* Minimum legal # cmd chars required */
-	kdb_cmdflags_t cmd_flags;	/* Command behaviour flags */
+	char    *name;			/* Command name */
+	kdb_func_t func;		/* Function to execute command */
+	char    *usage;			/* Usage String for this command */
+	char    *help;			/* Help message for this command */
+	short    minlen;		/* Minimum legal # cmd chars required */
+	kdb_cmdflags_t flags;		/* Command behaviour flags */
 	struct list_head list_node;	/* Command list */
 } kdbtab_t;
 
diff --git a/kernel/debug/kdb/kdb_bp.c b/kernel/debug/kdb/kdb_bp.c
index 2168f8dacb99..372025cf1ca3 100644
--- a/kernel/debug/kdb/kdb_bp.c
+++ b/kernel/debug/kdb/kdb_bp.c
@@ -523,51 +523,51 @@ static int kdb_ss(int argc, const char **argv)
 }
 
 static kdbtab_t bptab[] = {
-	{	.cmd_name = "bp",
-		.cmd_func = kdb_bp,
-		.cmd_usage = "[<vaddr>]",
-		.cmd_help = "Set/Display breakpoints",
-		.cmd_flags = KDB_ENABLE_FLOW_CTRL | KDB_REPEAT_NO_ARGS,
+	{	.name = "bp",
+		.func = kdb_bp,
+		.usage = "[<vaddr>]",
+		.help = "Set/Display breakpoints",
+		.flags = KDB_ENABLE_FLOW_CTRL | KDB_REPEAT_NO_ARGS,
 	},
-	{	.cmd_name = "bl",
-		.cmd_func = kdb_bp,
-		.cmd_usage = "[<vaddr>]",
-		.cmd_help = "Display breakpoints",
-		.cmd_flags = KDB_ENABLE_FLOW_CTRL | KDB_REPEAT_NO_ARGS,
+	{	.name = "bl",
+		.func = kdb_bp,
+		.usage = "[<vaddr>]",
+		.help = "Display breakpoints",
+		.flags = KDB_ENABLE_FLOW_CTRL | KDB_REPEAT_NO_ARGS,
 	},
-	{	.cmd_name = "bc",
-		.cmd_func = kdb_bc,
-		.cmd_usage = "<bpnum>",
-		.cmd_help = "Clear Breakpoint",
-		.cmd_flags = KDB_ENABLE_FLOW_CTRL,
+	{	.name = "bc",
+		.func = kdb_bc,
+		.usage = "<bpnum>",
+		.help = "Clear Breakpoint",
+		.flags = KDB_ENABLE_FLOW_CTRL,
 	},
-	{	.cmd_name = "be",
-		.cmd_func = kdb_bc,
-		.cmd_usage = "<bpnum>",
-		.cmd_help = "Enable Breakpoint",
-		.cmd_flags = KDB_ENABLE_FLOW_CTRL,
+	{	.name = "be",
+		.func = kdb_bc,
+		.usage = "<bpnum>",
+		.help = "Enable Breakpoint",
+		.flags = KDB_ENABLE_FLOW_CTRL,
 	},
-	{	.cmd_name = "bd",
-		.cmd_func = kdb_bc,
-		.cmd_usage = "<bpnum>",
-		.cmd_help = "Disable Breakpoint",
-		.cmd_flags = KDB_ENABLE_FLOW_CTRL,
+	{	.name = "bd",
+		.func = kdb_bc,
+		.usage = "<bpnum>",
+		.help = "Disable Breakpoint",
+		.flags = KDB_ENABLE_FLOW_CTRL,
 	},
-	{	.cmd_name = "ss",
-		.cmd_func = kdb_ss,
-		.cmd_usage = "",
-		.cmd_help = "Single Step",
-		.cmd_minlen = 1,
-		.cmd_flags = KDB_ENABLE_FLOW_CTRL | KDB_REPEAT_NO_ARGS,
+	{	.name = "ss",
+		.func = kdb_ss,
+		.usage = "",
+		.help = "Single Step",
+		.minlen = 1,
+		.flags = KDB_ENABLE_FLOW_CTRL | KDB_REPEAT_NO_ARGS,
 	},
 };
 
 static kdbtab_t bphcmd = {
-	.cmd_name = "bph",
-	.cmd_func = kdb_bp,
-	.cmd_usage = "[<vaddr>]",
-	.cmd_help = "[datar [length]|dataw [length]]   Set hw brk",
-	.cmd_flags = KDB_ENABLE_FLOW_CTRL | KDB_REPEAT_NO_ARGS,
+	.name = "bph",
+	.func = kdb_bp,
+	.usage = "[<vaddr>]",
+	.help = "[datar [length]|dataw [length]]   Set hw brk",
+	.flags = KDB_ENABLE_FLOW_CTRL | KDB_REPEAT_NO_ARGS,
 };
 
 /* Initialize the breakpoint table and register	breakpoint commands. */
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 7c7a2ef834fc..fa6deda894a1 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -711,10 +711,9 @@ static int kdb_defcmd(int argc, const char **argv)
 		struct kdb_macro_statement *kms;
 
 		list_for_each_entry(kp, &kdb_cmds_head, list_node) {
-			if (kp->cmd_func == kdb_exec_defcmd) {
+			if (kp->func == kdb_exec_defcmd) {
 				kdb_printf("defcmd %s \"%s\" \"%s\"\n",
-					   kp->cmd_name, kp->cmd_usage,
-					   kp->cmd_help);
+					   kp->name, kp->usage, kp->help);
 				kmp = container_of(kp, struct kdb_macro, cmd);
 				list_for_each_entry(kms, &kmp->statements,
 						    list_node)
@@ -735,34 +734,34 @@ static int kdb_defcmd(int argc, const char **argv)
 		goto fail_defcmd;
 
 	mp = &kdb_macro->cmd;
-	mp->cmd_func = kdb_exec_defcmd;
-	mp->cmd_minlen = 0;
-	mp->cmd_flags = KDB_ENABLE_ALWAYS_SAFE;
-	mp->cmd_name = kdb_strdup(argv[1], GFP_KDB);
-	if (!mp->cmd_name)
+	mp->func = kdb_exec_defcmd;
+	mp->minlen = 0;
+	mp->flags = KDB_ENABLE_ALWAYS_SAFE;
+	mp->name = kdb_strdup(argv[1], GFP_KDB);
+	if (!mp->name)
 		goto fail_name;
-	mp->cmd_usage = kdb_strdup(argv[2], GFP_KDB);
-	if (!mp->cmd_usage)
+	mp->usage = kdb_strdup(argv[2], GFP_KDB);
+	if (!mp->usage)
 		goto fail_usage;
-	mp->cmd_help = kdb_strdup(argv[3], GFP_KDB);
-	if (!mp->cmd_help)
+	mp->help = kdb_strdup(argv[3], GFP_KDB);
+	if (!mp->help)
 		goto fail_help;
-	if (mp->cmd_usage[0] == '"') {
-		strcpy(mp->cmd_usage, argv[2]+1);
-		mp->cmd_usage[strlen(mp->cmd_usage)-1] = '\0';
+	if (mp->usage[0] == '"') {
+		strcpy(mp->usage, argv[2]+1);
+		mp->usage[strlen(mp->usage)-1] = '\0';
 	}
-	if (mp->cmd_help[0] == '"') {
-		strcpy(mp->cmd_help, argv[3]+1);
-		mp->cmd_help[strlen(mp->cmd_help)-1] = '\0';
+	if (mp->help[0] == '"') {
+		strcpy(mp->help, argv[3]+1);
+		mp->help[strlen(mp->help)-1] = '\0';
 	}
 
 	INIT_LIST_HEAD(&kdb_macro->statements);
 	defcmd_in_progress = true;
 	return 0;
 fail_help:
-	kfree(mp->cmd_usage);
+	kfree(mp->usage);
 fail_usage:
-	kfree(mp->cmd_name);
+	kfree(mp->name);
 fail_name:
 	kfree(kdb_macro);
 fail_defcmd:
@@ -790,7 +789,7 @@ static int kdb_exec_defcmd(int argc, const char **argv)
 		return KDB_ARGCOUNT;
 
 	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
-		if (strcmp(kp->cmd_name, argv[0]) == 0)
+		if (strcmp(kp->name, argv[0]) == 0)
 			break;
 	}
 	if (list_entry_is_head(kp, &kdb_cmds_head, list_node)) {
@@ -804,7 +803,7 @@ static int kdb_exec_defcmd(int argc, const char **argv)
 		 * Recursive use of kdb_parse, do not use argv after this point.
 		 */
 		argv = NULL;
-		kdb_printf("[%s]kdb> %s\n", kmp->cmd.cmd_name, kms->statement);
+		kdb_printf("[%s]kdb> %s\n", kmp->cmd.name, kms->statement);
 		ret = kdb_parse(kms->statement);
 		if (ret)
 			return ret;
@@ -1016,11 +1015,11 @@ int kdb_parse(const char *cmdstr)
 		 * If this command is allowed to be abbreviated,
 		 * check to see if this is it.
 		 */
-		if (tp->cmd_minlen && (strlen(argv[0]) <= tp->cmd_minlen) &&
-		    (strncmp(argv[0], tp->cmd_name, tp->cmd_minlen) == 0))
+		if (tp->minlen && (strlen(argv[0]) <= tp->minlen) &&
+		    (strncmp(argv[0], tp->name, tp->minlen) == 0))
 			break;
 
-		if (strcmp(argv[0], tp->cmd_name) == 0)
+		if (strcmp(argv[0], tp->name) == 0)
 			break;
 	}
 
@@ -1031,8 +1030,7 @@ int kdb_parse(const char *cmdstr)
 	 */
 	if (list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
 		list_for_each_entry(tp, &kdb_cmds_head, list_node) {
-			if (strncmp(argv[0], tp->cmd_name,
-				    strlen(tp->cmd_name)) == 0)
+			if (strncmp(argv[0], tp->name, strlen(tp->name)) == 0)
 				break;
 		}
 	}
@@ -1040,19 +1038,19 @@ int kdb_parse(const char *cmdstr)
 	if (!list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
 		int result;
 
-		if (!kdb_check_flags(tp->cmd_flags, kdb_cmd_enabled, argc <= 1))
+		if (!kdb_check_flags(tp->flags, kdb_cmd_enabled, argc <= 1))
 			return KDB_NOPERM;
 
 		KDB_STATE_SET(CMD);
-		result = (*tp->cmd_func)(argc-1, (const char **)argv);
+		result = (*tp->func)(argc-1, (const char **)argv);
 		if (result && ignore_errors && result > KDB_CMD_GO)
 			result = 0;
 		KDB_STATE_CLEAR(CMD);
 
-		if (tp->cmd_flags & KDB_REPEAT_WITH_ARGS)
+		if (tp->flags & KDB_REPEAT_WITH_ARGS)
 			return result;
 
-		argc = tp->cmd_flags & KDB_REPEAT_NO_ARGS ? 1 : 0;
+		argc = tp->flags & KDB_REPEAT_NO_ARGS ? 1 : 0;
 		if (argv[argc])
 			*(argv[argc]) = '\0';
 		return result;
@@ -2419,12 +2417,12 @@ static int kdb_help(int argc, const char **argv)
 		char *space = "";
 		if (KDB_FLAG(CMD_INTERRUPT))
 			return 0;
-		if (!kdb_check_flags(kt->cmd_flags, kdb_cmd_enabled, true))
+		if (!kdb_check_flags(kt->flags, kdb_cmd_enabled, true))
 			continue;
-		if (strlen(kt->cmd_usage) > 20)
+		if (strlen(kt->usage) > 20)
 			space = "\n                                    ";
-		kdb_printf("%-15.15s %-20s%s%s\n", kt->cmd_name,
-			   kt->cmd_usage, space, kt->cmd_help);
+		kdb_printf("%-15.15s %-20s%s%s\n", kt->name,
+			   kt->usage, space, kt->help);
 	}
 	return 0;
 }
@@ -2633,9 +2631,9 @@ int kdb_register(kdbtab_t *cmd)
 	kdbtab_t *kp;
 
 	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
-		if (strcmp(kp->cmd_name, cmd->cmd_name) == 0) {
+		if (strcmp(kp->name, cmd->name) == 0) {
 			kdb_printf("Duplicate kdb cmd: %s, func %p help %s\n",
-				   cmd->cmd_name, cmd->cmd_func, cmd->cmd_help);
+				   cmd->name, cmd->func, cmd->help);
 			return 1;
 		}
 	}
@@ -2672,218 +2670,218 @@ void kdb_unregister(kdbtab_t *cmd)
 EXPORT_SYMBOL_GPL(kdb_unregister);
 
 static kdbtab_t maintab[] = {
-	{	.cmd_name = "md",
-		.cmd_func = kdb_md,
-		.cmd_usage = "<vaddr>",
-		.cmd_help = "Display Memory Contents, also mdWcN, e.g. md8c1",
-		.cmd_minlen = 1,
-		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
+	{	.name = "md",
+		.func = kdb_md,
+		.usage = "<vaddr>",
+		.help = "Display Memory Contents, also mdWcN, e.g. md8c1",
+		.minlen = 1,
+		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
 	},
-	{	.cmd_name = "mdr",
-		.cmd_func = kdb_md,
-		.cmd_usage = "<vaddr> <bytes>",
-		.cmd_help = "Display Raw Memory",
-		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
+	{	.name = "mdr",
+		.func = kdb_md,
+		.usage = "<vaddr> <bytes>",
+		.help = "Display Raw Memory",
+		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
 	},
-	{	.cmd_name = "mdp",
-		.cmd_func = kdb_md,
-		.cmd_usage = "<paddr> <bytes>",
-		.cmd_help = "Display Physical Memory",
-		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
+	{	.name = "mdp",
+		.func = kdb_md,
+		.usage = "<paddr> <bytes>",
+		.help = "Display Physical Memory",
+		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
 	},
-	{	.cmd_name = "mds",
-		.cmd_func = kdb_md,
-		.cmd_usage = "<vaddr>",
-		.cmd_help = "Display Memory Symbolically",
-		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
+	{	.name = "mds",
+		.func = kdb_md,
+		.usage = "<vaddr>",
+		.help = "Display Memory Symbolically",
+		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
 	},
-	{	.cmd_name = "mm",
-		.cmd_func = kdb_mm,
-		.cmd_usage = "<vaddr> <contents>",
-		.cmd_help = "Modify Memory Contents",
-		.cmd_flags = KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS,
+	{	.name = "mm",
+		.func = kdb_mm,
+		.usage = "<vaddr> <contents>",
+		.help = "Modify Memory Contents",
+		.flags = KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS,
 	},
-	{	.cmd_name = "go",
-		.cmd_func = kdb_go,
-		.cmd_usage = "[<vaddr>]",
-		.cmd_help = "Continue Execution",
-		.cmd_minlen = 1,
-		.cmd_flags = KDB_ENABLE_REG_WRITE |
+	{	.name = "go",
+		.func = kdb_go,
+		.usage = "[<vaddr>]",
+		.help = "Continue Execution",
+		.minlen = 1,
+		.flags = KDB_ENABLE_REG_WRITE |
 			     KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
 	},
-	{	.cmd_name = "rd",
-		.cmd_func = kdb_rd,
-		.cmd_usage = "",
-		.cmd_help = "Display Registers",
-		.cmd_flags = KDB_ENABLE_REG_READ,
+	{	.name = "rd",
+		.func = kdb_rd,
+		.usage = "",
+		.help = "Display Registers",
+		.flags = KDB_ENABLE_REG_READ,
 	},
-	{	.cmd_name = "rm",
-		.cmd_func = kdb_rm,
-		.cmd_usage = "<reg> <contents>",
-		.cmd_help = "Modify Registers",
-		.cmd_flags = KDB_ENABLE_REG_WRITE,
+	{	.name = "rm",
+		.func = kdb_rm,
+		.usage = "<reg> <contents>",
+		.help = "Modify Registers",
+		.flags = KDB_ENABLE_REG_WRITE,
 	},
-	{	.cmd_name = "ef",
-		.cmd_func = kdb_ef,
-		.cmd_usage = "<vaddr>",
-		.cmd_help = "Display exception frame",
-		.cmd_flags = KDB_ENABLE_MEM_READ,
+	{	.name = "ef",
+		.func = kdb_ef,
+		.usage = "<vaddr>",
+		.help = "Display exception frame",
+		.flags = KDB_ENABLE_MEM_READ,
 	},
-	{	.cmd_name = "bt",
-		.cmd_func = kdb_bt,
-		.cmd_usage = "[<vaddr>]",
-		.cmd_help = "Stack traceback",
-		.cmd_minlen = 1,
-		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
+	{	.name = "bt",
+		.func = kdb_bt,
+		.usage = "[<vaddr>]",
+		.help = "Stack traceback",
+		.minlen = 1,
+		.flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
 	},
-	{	.cmd_name = "btp",
-		.cmd_func = kdb_bt,
-		.cmd_usage = "<pid>",
-		.cmd_help = "Display stack for process <pid>",
-		.cmd_flags = KDB_ENABLE_INSPECT,
+	{	.name = "btp",
+		.func = kdb_bt,
+		.usage = "<pid>",
+		.help = "Display stack for process <pid>",
+		.flags = KDB_ENABLE_INSPECT,
 	},
-	{	.cmd_name = "bta",
-		.cmd_func = kdb_bt,
-		.cmd_usage = "[D|R|S|T|C|Z|E|U|I|M|A]",
-		.cmd_help = "Backtrace all processes matching state flag",
-		.cmd_flags = KDB_ENABLE_INSPECT,
+	{	.name = "bta",
+		.func = kdb_bt,
+		.usage = "[D|R|S|T|C|Z|E|U|I|M|A]",
+		.help = "Backtrace all processes matching state flag",
+		.flags = KDB_ENABLE_INSPECT,
 	},
-	{	.cmd_name = "btc",
-		.cmd_func = kdb_bt,
-		.cmd_usage = "",
-		.cmd_help = "Backtrace current process on each cpu",
-		.cmd_flags = KDB_ENABLE_INSPECT,
+	{	.name = "btc",
+		.func = kdb_bt,
+		.usage = "",
+		.help = "Backtrace current process on each cpu",
+		.flags = KDB_ENABLE_INSPECT,
 	},
-	{	.cmd_name = "btt",
-		.cmd_func = kdb_bt,
-		.cmd_usage = "<vaddr>",
-		.cmd_help = "Backtrace process given its struct task address",
-		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
+	{	.name = "btt",
+		.func = kdb_bt,
+		.usage = "<vaddr>",
+		.help = "Backtrace process given its struct task address",
+		.flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
 	},
-	{	.cmd_name = "env",
-		.cmd_func = kdb_env,
-		.cmd_usage = "",
-		.cmd_help = "Show environment variables",
-		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
+	{	.name = "env",
+		.func = kdb_env,
+		.usage = "",
+		.help = "Show environment variables",
+		.flags = KDB_ENABLE_ALWAYS_SAFE,
 	},
-	{	.cmd_name = "set",
-		.cmd_func = kdb_set,
-		.cmd_usage = "",
-		.cmd_help = "Set environment variables",
-		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
+	{	.name = "set",
+		.func = kdb_set,
+		.usage = "",
+		.help = "Set environment variables",
+		.flags = KDB_ENABLE_ALWAYS_SAFE,
 	},
-	{	.cmd_name = "help",
-		.cmd_func = kdb_help,
-		.cmd_usage = "",
-		.cmd_help = "Display Help Message",
-		.cmd_minlen = 1,
-		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
+	{	.name = "help",
+		.func = kdb_help,
+		.usage = "",
+		.help = "Display Help Message",
+		.minlen = 1,
+		.flags = KDB_ENABLE_ALWAYS_SAFE,
 	},
-	{	.cmd_name = "?",
-		.cmd_func = kdb_help,
-		.cmd_usage = "",
-		.cmd_help = "Display Help Message",
-		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
+	{	.name = "?",
+		.func = kdb_help,
+		.usage = "",
+		.help = "Display Help Message",
+		.flags = KDB_ENABLE_ALWAYS_SAFE,
 	},
-	{	.cmd_name = "cpu",
-		.cmd_func = kdb_cpu,
-		.cmd_usage = "<cpunum>",
-		.cmd_help = "Switch to new cpu",
-		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
+	{	.name = "cpu",
+		.func = kdb_cpu,
+		.usage = "<cpunum>",
+		.help = "Switch to new cpu",
+		.flags = KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
 	},
-	{	.cmd_name = "kgdb",
-		.cmd_func = kdb_kgdb,
-		.cmd_usage = "",
-		.cmd_help = "Enter kgdb mode",
-		.cmd_flags = 0,
+	{	.name = "kgdb",
+		.func = kdb_kgdb,
+		.usage = "",
+		.help = "Enter kgdb mode",
+		.flags = 0,
 	},
-	{	.cmd_name = "ps",
-		.cmd_func = kdb_ps,
-		.cmd_usage = "[<flags>|A]",
-		.cmd_help = "Display active task list",
-		.cmd_flags = KDB_ENABLE_INSPECT,
+	{	.name = "ps",
+		.func = kdb_ps,
+		.usage = "[<flags>|A]",
+		.help = "Display active task list",
+		.flags = KDB_ENABLE_INSPECT,
 	},
-	{	.cmd_name = "pid",
-		.cmd_func = kdb_pid,
-		.cmd_usage = "<pidnum>",
-		.cmd_help = "Switch to another task",
-		.cmd_flags = KDB_ENABLE_INSPECT,
+	{	.name = "pid",
+		.func = kdb_pid,
+		.usage = "<pidnum>",
+		.help = "Switch to another task",
+		.flags = KDB_ENABLE_INSPECT,
 	},
-	{	.cmd_name = "reboot",
-		.cmd_func = kdb_reboot,
-		.cmd_usage = "",
-		.cmd_help = "Reboot the machine immediately",
-		.cmd_flags = KDB_ENABLE_REBOOT,
+	{	.name = "reboot",
+		.func = kdb_reboot,
+		.usage = "",
+		.help = "Reboot the machine immediately",
+		.flags = KDB_ENABLE_REBOOT,
 	},
 #if defined(CONFIG_MODULES)
-	{	.cmd_name = "lsmod",
-		.cmd_func = kdb_lsmod,
-		.cmd_usage = "",
-		.cmd_help = "List loaded kernel modules",
-		.cmd_flags = KDB_ENABLE_INSPECT,
+	{	.name = "lsmod",
+		.func = kdb_lsmod,
+		.usage = "",
+		.help = "List loaded kernel modules",
+		.flags = KDB_ENABLE_INSPECT,
 	},
 #endif
 #if defined(CONFIG_MAGIC_SYSRQ)
-	{	.cmd_name = "sr",
-		.cmd_func = kdb_sr,
-		.cmd_usage = "<key>",
-		.cmd_help = "Magic SysRq key",
-		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
+	{	.name = "sr",
+		.func = kdb_sr,
+		.usage = "<key>",
+		.help = "Magic SysRq key",
+		.flags = KDB_ENABLE_ALWAYS_SAFE,
 	},
 #endif
 #if defined(CONFIG_PRINTK)
-	{	.cmd_name = "dmesg",
-		.cmd_func = kdb_dmesg,
-		.cmd_usage = "[lines]",
-		.cmd_help = "Display syslog buffer",
-		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
+	{	.name = "dmesg",
+		.func = kdb_dmesg,
+		.usage = "[lines]",
+		.help = "Display syslog buffer",
+		.flags = KDB_ENABLE_ALWAYS_SAFE,
 	},
 #endif
-	{	.cmd_name = "defcmd",
-		.cmd_func = kdb_defcmd,
-		.cmd_usage = "name \"usage\" \"help\"",
-		.cmd_help = "Define a set of commands, down to endefcmd",
+	{	.name = "defcmd",
+		.func = kdb_defcmd,
+		.usage = "name \"usage\" \"help\"",
+		.help = "Define a set of commands, down to endefcmd",
 		/*
 		 * Macros are always safe because when executed each
 		 * internal command re-enters kdb_parse() and is safety
 		 * checked individually.
 		 */
-		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
+		.flags = KDB_ENABLE_ALWAYS_SAFE,
 	},
-	{	.cmd_name = "kill",
-		.cmd_func = kdb_kill,
-		.cmd_usage = "<-signal> <pid>",
-		.cmd_help = "Send a signal to a process",
-		.cmd_flags = KDB_ENABLE_SIGNAL,
+	{	.name = "kill",
+		.func = kdb_kill,
+		.usage = "<-signal> <pid>",
+		.help = "Send a signal to a process",
+		.flags = KDB_ENABLE_SIGNAL,
 	},
-	{	.cmd_name = "summary",
-		.cmd_func = kdb_summary,
-		.cmd_usage = "",
-		.cmd_help = "Summarize the system",
-		.cmd_minlen = 4,
-		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
+	{	.name = "summary",
+		.func = kdb_summary,
+		.usage = "",
+		.help = "Summarize the system",
+		.minlen = 4,
+		.flags = KDB_ENABLE_ALWAYS_SAFE,
 	},
-	{	.cmd_name = "per_cpu",
-		.cmd_func = kdb_per_cpu,
-		.cmd_usage = "<sym> [<bytes>] [<cpu>]",
-		.cmd_help = "Display per_cpu variables",
-		.cmd_minlen = 3,
-		.cmd_flags = KDB_ENABLE_MEM_READ,
+	{	.name = "per_cpu",
+		.func = kdb_per_cpu,
+		.usage = "<sym> [<bytes>] [<cpu>]",
+		.help = "Display per_cpu variables",
+		.minlen = 3,
+		.flags = KDB_ENABLE_MEM_READ,
 	},
-	{	.cmd_name = "grephelp",
-		.cmd_func = kdb_grep_help,
-		.cmd_usage = "",
-		.cmd_help = "Display help on | grep",
-		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
+	{	.name = "grephelp",
+		.func = kdb_grep_help,
+		.usage = "",
+		.help = "Display help on | grep",
+		.flags = KDB_ENABLE_ALWAYS_SAFE,
 	},
 };
 
 static kdbtab_t nmicmd = {
-	.cmd_name = "disable_nmi",
-	.cmd_func = kdb_disable_nmi,
-	.cmd_usage = "",
-	.cmd_help = "Disable NMI entry to KDB",
-	.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
+	.name = "disable_nmi",
+	.func = kdb_disable_nmi,
+	.usage = "",
+	.help = "Disable NMI entry to KDB",
+	.flags = KDB_ENABLE_ALWAYS_SAFE,
 };
 
 /* Initialize the kdb command table. */
diff --git a/kernel/trace/trace_kdb.c b/kernel/trace/trace_kdb.c
index 6c4f92c79e43..59857a1ee44c 100644
--- a/kernel/trace/trace_kdb.c
+++ b/kernel/trace/trace_kdb.c
@@ -148,11 +148,11 @@ static int kdb_ftdump(int argc, const char **argv)
 }
 
 static kdbtab_t ftdump_cmd = {
-	.cmd_name = "ftdump",
-	.cmd_func = kdb_ftdump,
-	.cmd_usage = "[skip_#entries] [cpu]",
-	.cmd_help = "Dump ftrace log; -skip dumps last #entries",
-	.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
+	.name = "ftdump",
+	.func = kdb_ftdump,
+	.usage = "[skip_#entries] [cpu]",
+	.help = "Dump ftrace log; -skip dumps last #entries",
+	.flags = KDB_ENABLE_ALWAYS_SAFE,
 };
 
 static __init int kdb_ftrace_register(void)
diff --git a/samples/kdb/kdb_hello.c b/samples/kdb/kdb_hello.c
index 9ad514a6648b..82736e5a5e32 100644
--- a/samples/kdb/kdb_hello.c
+++ b/samples/kdb/kdb_hello.c
@@ -29,10 +29,10 @@ static int kdb_hello_cmd(int argc, const char **argv)
 }
 
 static kdbtab_t hello_cmd = {
-	.cmd_name = "hello",
-	.cmd_func = kdb_hello_cmd,
-	.cmd_usage = "[string]",
-	.cmd_help = "Say Hello World or Hello [string]",
+	.name = "hello",
+	.func = kdb_hello_cmd,
+	.usage = "[string]",
+	.help = "Say Hello World or Hello [string]",
 };
 
 static int __init kdb_hello_cmd_init(void)
-- 
cgit 


From f8416aa29185468e0d914ba4b2a330fd53ee263f Mon Sep 17 00:00:00 2001
From: Cai Huoqing <caihuoqing@baidu.com>
Date: Mon, 6 Sep 2021 19:23:02 +0800
Subject: kernel: debug: Convert to SPDX identifier

use SPDX-License-Identifier instead of a verbose license text

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Link: https://lore.kernel.org/r/20210906112302.937-1-caihuoqing@baidu.com
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
---
 kernel/debug/debug_core.c | 5 +----
 kernel/debug/gdbstub.c    | 5 +----
 2 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index b4aa6bb6b2bd..da06a5553835 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Kernel Debug Core
  *
@@ -22,10 +23,6 @@
  *
  * Original KGDB stub: David Grothe <dave@gcom.com>,
  * Tigran Aivazian <tigran@sco.com>
- *
- * This file is licensed under the terms of the GNU General Public License
- * version 2. This program is licensed "as is" without any warranty of any
- * kind, whether express or implied.
  */
 
 #define pr_fmt(fmt) "KGDB: " fmt
diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c
index b6f28fad4307..9d34d2364b5a 100644
--- a/kernel/debug/gdbstub.c
+++ b/kernel/debug/gdbstub.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Kernel Debug Core
  *
@@ -22,10 +23,6 @@
  *
  * Original KGDB stub: David Grothe <dave@gcom.com>,
  * Tigran Aivazian <tigran@sco.com>
- *
- * This file is licensed under the terms of the GNU General Public License
- * version 2. This program is licensed "as is" without any warranty of any
- * kind, whether express or implied.
  */
 
 #include <linux/kernel.h>
-- 
cgit