Merge tag 'kgdb-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux

Pull kgdb updates from Daniel Thompson:
 "Two cleanups this cycle. The larger of which is the removal of a
  private allocator within kdb and replacing it with regular memory
  allocation. The other adopts the simplified version of strscpy() in a
  couple of places in kdb"

* tag 'kgdb-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
  kdb: Remove optional size arguments from strscpy() calls
  kdb: remove usage of static environment buffer

Author: torvalds

include/linux/kdb.h

@@ -104,7 +104,7 @@ extern int kdb_initial_cpu;
 #define KDB_NOENVVALUE	(-6)
 #define KDB_NOTIMP	(-7)
 #define KDB_ENVFULL	(-8)
-#define KDB_ENVBUFFULL	(-9)
+#define KDB_KMALLOCFAILED	(-9)
 #define KDB_TOOMANYBPT	(-10)
 #define KDB_TOOMANYDBREGS (-11)
 #define KDB_DUPBPT	(-12)

kernel/debug/kdb/kdb_io.c

@@ -334,7 +334,7 @@ static char *kdb_read(char *buffer, size_t bufsize)
 		*cp = '\0';
 		p_tmp = strrchr(buffer, ' ');
 		p_tmp = (p_tmp ? p_tmp + 1 : buffer);
-		strscpy(tmpbuffer, p_tmp, sizeof(tmpbuffer));
+		strscpy(tmpbuffer, p_tmp);
 		*cp = tmp;
 
 		len = strlen(tmpbuffer);
@@ -452,7 +452,7 @@ static char *kdb_read(char *buffer, size_t bufsize)
 char *kdb_getstr(char *buffer, size_t bufsize, const char *prompt)
 {
 	if (prompt && kdb_prompt_str != prompt)
-		strscpy(kdb_prompt_str, prompt, CMD_BUFLEN);
+		strscpy(kdb_prompt_str, prompt);
 	kdb_printf("%s", kdb_prompt_str);
 	kdb_nextline = 1;	/* Prompt and input resets line number */
 	return kdb_read(buffer, bufsize);

kernel/debug/kdb/kdb_main.c

@@ -105,7 +105,7 @@ static kdbmsg_t kdbmsgs[] = {
 	KDBMSG(NOENVVALUE, "Environment variable should have value"),
 	KDBMSG(NOTIMP, "Command not implemented"),
 	KDBMSG(ENVFULL, "Environment full"),
-	KDBMSG(ENVBUFFULL, "Environment buffer full"),
+	KDBMSG(KMALLOCFAILED, "Failed to allocate memory"),
 	KDBMSG(TOOMANYBPT, "Too many breakpoints defined"),
 #ifdef CONFIG_CPU_XSCALE
 	KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"),
@@ -130,13 +130,9 @@ static const int __nkdb_err = ARRAY_SIZE(kdbmsgs);
 
 
 /*
- * Initial environment.   This is all kept static and local to
- * this file.   We don't want to rely on the memory allocation
- * mechanisms in the kernel, so we use a very limited allocate-only
- * heap for new and altered environment variables.  The entire
- * environment is limited to a fixed number of entries (add more
- * to __env[] if required) and a fixed amount of heap (add more to
- * KDB_ENVBUFSIZE if required).
+ * Initial environment. This is all kept static and local to this file.
+ * The entire environment is limited to a fixed number of entries
+ * (add more to __env[] if required)
  */
 
 static char *__env[31] = {
@@ -258,35 +254,6 @@ char *kdbgetenv(const char *match)
 	return NULL;
 }
 
-/*
- * kdballocenv - This function is used to allocate bytes for
- *	environment entries.
- * Parameters:
- *	bytes	The number of bytes to allocate in the static buffer.
- * Returns:
- *	A pointer to the allocated space in the buffer on success.
- *	NULL if bytes > size available in the envbuffer.
- * Remarks:
- *	We use a static environment buffer (envbuffer) to hold the values
- *	of dynamically generated environment variables (see kdb_set).  Buffer
- *	space once allocated is never free'd, so over time, the amount of space
- *	(currently 512 bytes) will be exhausted if env variables are changed
- *	frequently.
- */
-static char *kdballocenv(size_t bytes)
-{
-#define	KDB_ENVBUFSIZE	512
-	static char envbuffer[KDB_ENVBUFSIZE];
-	static int envbufsize;
-	char *ep = NULL;
-
-	if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
-		ep = &envbuffer[envbufsize];
-		envbufsize += bytes;
-	}
-	return ep;
-}
-
 /*
  * kdbgetulenv - This function will return the value of an unsigned
  *	long-valued environment variable.
@@ -348,9 +315,9 @@ static int kdb_setenv(const char *var, const char *val)
 
 	varlen = strlen(var);
 	vallen = strlen(val);
-	ep = kdballocenv(varlen + vallen + 2);
-	if (ep == (char *)0)
-		return KDB_ENVBUFFULL;
+	ep = kmalloc(varlen + vallen + 2, GFP_KDB);
+	if (!ep)
+		return KDB_KMALLOCFAILED;
 
 	sprintf(ep, "%s=%s", var, val);
 
@@ -359,6 +326,7 @@ static int kdb_setenv(const char *var, const char *val)
 		 && ((strncmp(__env[i], var, varlen) == 0)
 		   && ((__env[i][varlen] == '\0')
 		    || (__env[i][varlen] == '=')))) {
+			kfree_const(__env[i]);
 			__env[i] = ep;
 			return 0;
 		}