diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 434877e..1c50327 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -86,7 +86,7 @@ jobs:
 
     - name: configure
       run: |
-       ./configure --prefix=/usr --host=${{ matrix.host }} --enable-werror --build=x86_64-linux-gnu CFLAGS='-O2 -g'
+       ./configure --prefix=/usr --host=${{ matrix.host }} --enable-werror --build=x86_64-linux-gnu CFLAGS='-O2 -g -Wextra -Wno-error=unused-parameter -Wno-error=nonnull'
 
     - name: Collect config.log
       if: ${{ failure() }}
diff --git a/src/drmgr/common.c b/src/drmgr/common.c
index 70f4dfd..15f8939 100644
--- a/src/drmgr/common.c
+++ b/src/drmgr/common.c
@@ -94,7 +94,7 @@ static const char * const hook_action_name[] = {
  * @param level level to set the output level to
  */
 inline void
-set_output_level(int level)
+set_output_level(unsigned level)
 {
 	output_level = level;
 
@@ -730,7 +730,7 @@ update_property(const char *buf, size_t len)
  * @returns 0 on success, -1 otherwise
  */
 static int
-get_att_prop(const char *path, const char *name, char *buf, size_t buf_sz,
+get_att_prop(const char *path, const char *name, char *buf, ssize_t buf_sz,
 	     const char *attr_type)
 {
 	FILE *fp;
@@ -797,7 +797,7 @@ get_att_prop(const char *path, const char *name, char *buf, size_t buf_sz,
  * @returns 0 on success, !0 otherwise
  */
 int
-get_property(const char *path, const char *property, void *buf, size_t buf_sz)
+get_property(const char *path, const char *property, void *buf, ssize_t buf_sz)
 {
 	return get_att_prop(path, property, buf, buf_sz, NULL);
 }
@@ -814,7 +814,7 @@ get_property(const char *path, const char *property, void *buf, size_t buf_sz)
  */
 int
 get_int_attribute(const char *path, const char *attribute, void *buf,
-		  size_t buf_sz)
+		  ssize_t buf_sz)
 {
 	return get_att_prop(path, attribute, buf, buf_sz, "%i");
 }
@@ -831,7 +831,7 @@ get_int_attribute(const char *path, const char *attribute, void *buf,
  */
 int
 get_str_attribute(const char *path, const char *attribute, void *buf,
-		  size_t buf_sz)
+		  ssize_t buf_sz)
 {
 	return get_att_prop(path, attribute, buf, buf_sz, "%s");
 }
@@ -1270,10 +1270,10 @@ int update_sysparm(void)
 			return 1;
 		}
 
-		usr_drc_count = -usr_drc_count;
+		return set_sysparm(linux_parm, curval - usr_drc_count);
+	} else {
+		return set_sysparm(linux_parm, curval + usr_drc_count);
 	}
-	
-	return set_sysparm(linux_parm, curval + usr_drc_count);
 }
 
 int
diff --git a/src/drmgr/common_numa.c b/src/drmgr/common_numa.c
index 898aab6..cf8a1cf 100644
--- a/src/drmgr/common_numa.c
+++ b/src/drmgr/common_numa.c
@@ -27,7 +27,7 @@
 #include "drmem.h"		/* for DYNAMIC_RECONFIG_MEM */
 #include "common_numa.h"
 
-struct ppcnuma_node *ppcnuma_fetch_node(struct ppcnuma_topology *numa, int nid)
+struct ppcnuma_node *ppcnuma_fetch_node(struct ppcnuma_topology *numa, unsigned nid)
 {
 	struct ppcnuma_node *node;
 
@@ -67,7 +67,8 @@ static int read_numa_topology(struct ppcnuma_topology *numa)
 {
 	struct bitmask *cpus;
 	struct ppcnuma_node *node;
-	int rc, max_node, nid, i;
+	int rc;
+	unsigned max_node, nid, i;
 
 	if (numa_available() < 0)
 		return -ENOENT;
diff --git a/src/drmgr/common_numa.h b/src/drmgr/common_numa.h
index c209a3e..06e28ce 100644
--- a/src/drmgr/common_numa.h
+++ b/src/drmgr/common_numa.h
@@ -46,10 +46,10 @@ struct ppcnuma_topology {
 
 int ppcnuma_get_topology(struct ppcnuma_topology *numa);
 struct ppcnuma_node *ppcnuma_fetch_node(struct ppcnuma_topology *numa,
-					int node_id);
+					unsigned node_id);
 
-static inline int ppcnuma_next_node(struct ppcnuma_topology *numa, int nid,
-				    struct ppcnuma_node **node)
+static inline unsigned ppcnuma_next_node(struct ppcnuma_topology *numa, unsigned nid,
+				         struct ppcnuma_node **node)
 {
 	for (nid++; nid <= numa->node_max; nid++)
 		if (numa->nodes[nid]) {
diff --git a/src/drmgr/common_ofdt.c b/src/drmgr/common_ofdt.c
index 1e5fe53..02c1f70 100644
--- a/src/drmgr/common_ofdt.c
+++ b/src/drmgr/common_ofdt.c
@@ -844,7 +844,7 @@ int get_min_common_depth(void)
 	size = load_property(RTAS_DIRECTORY, ASSOC_REF_POINTS, &p);
 	if (size <= 0)
 		return size;
-	if (size < sizeof(uint32_t)) {
+	if (size < (int)sizeof(uint32_t)) {
 		report_unknown_error(__FILE__, __LINE__);
 		free(p);
 		return -EINVAL;
@@ -857,7 +857,7 @@ int get_min_common_depth(void)
 }
 
 int get_assoc_arrays(const char *dir, struct assoc_arrays *aa,
-		     int min_common_depth)
+		     unsigned min_common_depth)
 {
 	int size;
 	int rc;
@@ -884,7 +884,7 @@ int get_assoc_arrays(const char *dir, struct assoc_arrays *aa,
 	}
 
 	/* Sanity check */
-	if (size != (aa->n_arrays * aa->array_sz + 2)) {
+	if ((unsigned)size != (aa->n_arrays * aa->array_sz + 2)) {
 		say(ERROR, "Bad size of the associativity lookup arrays\n");
 		goto out_free;
 	}
@@ -908,7 +908,7 @@ int get_assoc_arrays(const char *dir, struct assoc_arrays *aa,
  * Read the associativity property and return the node id matching the
  * min_common_depth entry.
  */
-int of_associativity_to_node(const char *dir, int min_common_depth)
+int of_associativity_to_node(const char *dir, unsigned min_common_depth)
 {
 	int size;
 	uint32_t *prop;
diff --git a/src/drmgr/common_pci.c b/src/drmgr/common_pci.c
index 683d72d..8226e63 100644
--- a/src/drmgr/common_pci.c
+++ b/src/drmgr/common_pci.c
@@ -1050,7 +1050,7 @@ get_bus_id(char *loc_code)
 	DIR *d;
 	struct dirent *ent;
 	char *dir = "/sys/bus/pci/slots";
-	int inlen;
+	size_t inlen;
 	char *ptr;
 
 	/* Strip any newline from the input location */
diff --git a/src/drmgr/dr.h b/src/drmgr/dr.h
index 72ede55..a369a6e 100644
--- a/src/drmgr/dr.h
+++ b/src/drmgr/dr.h
@@ -30,7 +30,7 @@
 #include "rtas_calls.h"
 #include "drpci.h"
 
-extern int output_level;
+extern unsigned output_level;
 extern int log_fd;
 
 extern int read_dynamic_memory_v2;
@@ -79,7 +79,7 @@ extern int usr_timeout;
 extern char *usr_drc_name;
 extern uint32_t usr_drc_index;
 extern int usr_prompt;
-extern int usr_drc_count;
+extern unsigned usr_drc_count;
 extern enum drc_type usr_drc_type;
 extern char *usr_p_option;
 extern char *usr_t_option;
@@ -110,9 +110,9 @@ int add_device_tree_nodes(char *, struct of_node *);
 int remove_device_tree_nodes(const char *path);
 
 int update_property(const char *, size_t);
-int get_property(const char *, const char *, void *, size_t);
-int get_int_attribute(const char *, const char *, void *, size_t);
-int get_str_attribute(const char *, const char *, void *, size_t);
+int get_property(const char *, const char *, void *, ssize_t);
+int get_int_attribute(const char *, const char *, void *, ssize_t);
+int get_str_attribute(const char *, const char *, void *, ssize_t);
 int get_ofdt_uint_property(const char *, const char *, uint *);
 int get_property_size(const char *, const char *);
 int signal_handler(int, int, struct sigcontext *);
@@ -133,7 +133,7 @@ int cpu_entitlement_capable(void);
 int mem_entitlement_capable(void);
 void print_dlpar_capabilities(void);
 
-void set_output_level(int);
+void set_output_level(unsigned);
 
 int run_hooks(enum drc_type drc_type, enum drmgr_action, enum hook_phase phase,
 	      int drc_count);
diff --git a/src/drmgr/dracc_chrp_acc.c b/src/drmgr/dracc_chrp_acc.c
index 527be56..b8e2f75 100644
--- a/src/drmgr/dracc_chrp_acc.c
+++ b/src/drmgr/dracc_chrp_acc.c
@@ -79,11 +79,6 @@ int dracc_chrp_acc(void)
 		return -1;
 	}
 
-	if (usr_drc_count < 0) {
-		say(ERROR, "Invalid QoS credit count %d\n", usr_drc_count);
-		return -1;
-	}
-
 	fd = open(SYSFS_VAS_QOSCREDIT_FILE, O_WRONLY);
 	if (fd < 0) {
 		say(ERROR, "Could not open \"%s\" to write QoS credits\n",
diff --git a/src/drmgr/drmem.h b/src/drmgr/drmem.h
index 48108c5..550cbd2 100644
--- a/src/drmgr/drmem.h
+++ b/src/drmgr/drmem.h
@@ -24,7 +24,7 @@ struct lmb_list_head {
 	struct dr_node	*last;
 	char		*drconf_buf;
 	int		drconf_buf_sz;
-	int		lmbs_modified;
+	unsigned	lmbs_modified;
 	int		sort;
 	int		lmbs_found;
 };
diff --git a/src/drmgr/drmgr.c b/src/drmgr/drmgr.c
index bb3e175..01f4cc1 100644
--- a/src/drmgr/drmgr.c
+++ b/src/drmgr/drmgr.c
@@ -32,7 +32,7 @@
 
 #define DRMGR_ARGS	"ac:d:Iimnp:P:Qq:Rrs:w:t:hCVH"
 
-int output_level = 1; /* default to lowest output level */
+unsigned output_level = 1; /* default to lowest output level */
 
 int log_fd = 0;
 int action_cnt = 0;
@@ -202,7 +202,7 @@ int parse_options(int argc, char *argv[])
 			display_capabilities = 1;
 			break;
 		    case 'd':
-			set_output_level(atoi(optarg));
+			set_output_level(strtoul(optarg, NULL, 10));
 			break;
 		    case 'I':
 			usr_slot_identification = 0;
diff --git a/src/drmgr/drslot_chrp_cpu.c b/src/drmgr/drslot_chrp_cpu.c
index 3ef24f4..a6bac4a 100644
--- a/src/drmgr/drslot_chrp_cpu.c
+++ b/src/drmgr/drslot_chrp_cpu.c
@@ -231,7 +231,7 @@ struct dr_node *get_available_cpu(struct dr_info *dr_info)
  * @param nr_cpus
  * @returns 0 on success, !0 otherwise
  */
-static int add_cpus(struct dr_info *dr_info, int *count)
+static int add_cpus(struct dr_info *dr_info, unsigned *count)
 {
 	int rc = -1;
 	struct dr_node *cpu = NULL;
@@ -285,7 +285,7 @@ static int add_cpus(struct dr_info *dr_info, int *count)
  * @param nr_cpus
  * @returns 0 on success, !0 otherwise
  */
-static int remove_cpus(struct dr_info *dr_info, int *count)
+static int remove_cpus(struct dr_info *dr_info, unsigned *count)
 {
 	int rc = 0;
 	struct dr_node *cpu;
@@ -405,7 +405,8 @@ int valid_cpu_options(void)
 int drslot_chrp_cpu(void)
 {
 	struct dr_info dr_info;
-	int rc, count = 0;
+	int rc;
+	unsigned count = 0;
 
 	if (! cpu_dlpar_capable()) {
 		say(ERROR, "CPU DLPAR capability is not enabled on this "
diff --git a/src/drmgr/drslot_chrp_mem.c b/src/drmgr/drslot_chrp_mem.c
index d37ee80..395997b 100644
--- a/src/drmgr/drslot_chrp_mem.c
+++ b/src/drmgr/drslot_chrp_mem.c
@@ -312,12 +312,14 @@ get_mem_node_lmbs(struct lmb_list_head *lmb_list)
 
 static int link_lmb_to_numa_node(struct dr_node *lmb)
 {
-	int nid;
+	int ret;
+	unsigned nid;
 	struct ppcnuma_node *node;
 
-	nid = aa_index_to_node(&numa.aa, lmb->lmb_aa_index);
-	if (nid == -1)
+	ret = aa_index_to_node(&numa.aa, lmb->lmb_aa_index);
+	if (ret == -1)
 		return 0;
+	nid = ret;
 
 	node = ppcnuma_fetch_node(&numa, nid);
 	if (!node)
@@ -439,7 +441,8 @@ int get_dynamic_reconfig_lmbs_v2(uint64_t lmb_sz,
 {
 	struct drconf_mem_v2 *drmem;
 	uint32_t lmb_sets;
-	int i, rc = 0;
+	unsigned i;
+	int rc;
 
 	lmb_list->drconf_buf_sz = get_property_size(DYNAMIC_RECONFIG_MEM,
 						   "ibm,dynamic-memory-v2");
@@ -469,7 +472,7 @@ int get_dynamic_reconfig_lmbs_v2(uint64_t lmb_sz,
 	for (i = 0; i < lmb_sets; i++) {
 		uint32_t drc_index, seq_lmbs;
 		uint64_t address;
-		int j;
+		unsigned j;
 
 		address = be64toh(drmem->base_addr);
 		drc_index = be32toh(drmem->drc_index);
@@ -739,7 +742,7 @@ static void update_drconf_affinity(struct dr_node *lmb,
 	uint32_t assoc_entries;
 	uint32_t assoc_entry_sz;
 	uint32_t *prop_val;
-	int i;
+	unsigned i;
 
 	/* find the ibm,associativity property */
 	node = lmb->lmb_of_node;
@@ -1470,7 +1473,8 @@ static int remove_lmb_by_index(uint32_t drc_index)
 static int remove_lmb_from_node(struct ppcnuma_node *node, uint32_t count)
 {
 	struct dr_node *lmb;
-	int err, done = 0, unlinked = 0;
+	int err;
+	unsigned done = 0, unlinked = 0;
 
 	say(DEBUG, "Try removing %d / %d LMBs from node %d\n",
 	    count, node->n_lmbs, node->node_id);
@@ -1521,7 +1525,7 @@ static int remove_lmb_from_node(struct ppcnuma_node *node, uint32_t count)
 static void update_cpuless_node_ratio(void)
 {
 	struct ppcnuma_node *node;
-	int nid;
+	unsigned nid;
 
 	/*
 	 * Assumptions:
@@ -1549,7 +1553,7 @@ static void update_cpuless_node_ratio(void)
 static int remove_cpuless_lmbs(uint32_t count)
 {
 	struct ppcnuma_node *node;
-	int nid;
+	unsigned nid;
 	uint32_t total = count, todo, done = 0, this_loop;
 
 	while (count) {
@@ -1593,7 +1597,7 @@ static int remove_cpuless_lmbs(uint32_t count)
 
 static void update_node_ratio(void)
 {
-	int nid;
+	unsigned nid;
 	struct ppcnuma_node *node, *n, **p;
 	uint32_t cpu_ratio, mem_ratio;
 
@@ -1695,7 +1699,7 @@ static void build_numa_topology(void)
 
 static void clear_numa_lmb_links(void)
 {
-	int nid;
+	unsigned nid;
 	struct ppcnuma_node *node;
 
 	ppcnuma_foreach_node(&numa, nid, node)
@@ -1706,7 +1710,7 @@ static int numa_based_remove(uint32_t count)
 {
 	struct lmb_list_head *lmb_list;
 	struct ppcnuma_node *node;
-	int nid;
+	unsigned nid;
 	uint32_t done = 0;
 
 	/*
diff --git a/src/drmgr/lparnumascore.c b/src/drmgr/lparnumascore.c
index ffb974c..559d838 100644
--- a/src/drmgr/lparnumascore.c
+++ b/src/drmgr/lparnumascore.c
@@ -39,9 +39,9 @@
 
 #define NUMA_NO_NODE	-1
 
-int output_level = 0;
+unsigned output_level = 0;
 int log_fd = 0;
-int min_common_depth;
+unsigned min_common_depth;
 int read_dynamic_memory_v2 = 1;
 
 static bool check_node(char *syspath, int node)
@@ -249,7 +249,7 @@ static int parse_options(int argc, char *argv[])
 			}
 			break;
 		case 'd':
-			set_output_level(atoi(optarg));
+			set_output_level(strtoul(optarg, NULL, 10));
 			break;
 		case 'h':
 			usage();
@@ -276,6 +276,8 @@ static int parse_options(int argc, char *argv[])
 
 int main(int argc, char *argv[])
 {
+	int rc;
+
 	if (parse_options(argc, argv))
 		exit(1);
 
@@ -290,9 +292,10 @@ int main(int argc, char *argv[])
 		exit(1);
 	}
 
-	min_common_depth = get_min_common_depth();
-	if (min_common_depth < 0)
+	rc = get_min_common_depth();
+	if (rc < 0)
 		exit(1);
+	min_common_depth = rc;
 
 	switch (usr_drc_type) {
 	case DRC_TYPE_CPU:
diff --git a/src/drmgr/lsslot.c b/src/drmgr/lsslot.c
index 83e9e85..6a0c305 100644
--- a/src/drmgr/lsslot.c
+++ b/src/drmgr/lsslot.c
@@ -33,7 +33,7 @@
 
 #include "options.c"
 
-int output_level = 0;
+unsigned output_level = 0;
 int log_fd = 0;
 
 int read_dynamic_memory_v2 = 1;
@@ -435,7 +435,7 @@ static void parse_options(int argc, char *argv[])
 			break;
 
 		    case 'd':
-			set_output_level(atoi(optarg));
+			set_output_level(strtoul(optarg, NULL, 10));
 			break;
 
 		    case 'F':
diff --git a/src/drmgr/ofdt.h b/src/drmgr/ofdt.h
index e9ebd03..ca28b4c 100644
--- a/src/drmgr/ofdt.h
+++ b/src/drmgr/ofdt.h
@@ -182,8 +182,8 @@ int get_drc_by_index(uint32_t, struct dr_connector *, char *, char *);
 
 int get_min_common_depth(void);
 int get_assoc_arrays(const char *dir, struct assoc_arrays *aa,
-		     int min_common_depth);
-int of_associativity_to_node(const char *dir, int min_common_depth);
+		     unsigned min_common_depth);
+int of_associativity_to_node(const char *dir, unsigned min_common_depth);
 int init_node(struct dr_node *);
 
 static inline int aa_index_to_node(struct assoc_arrays *aa, uint32_t aa_index)
diff --git a/src/drmgr/options.c b/src/drmgr/options.c
index fba9158..7925072 100644
--- a/src/drmgr/options.c
+++ b/src/drmgr/options.c
@@ -45,7 +45,7 @@ int usr_prompt = 1;
 
 /* user-specified quantity of devices to add/remove */
 /* user-specified quantity of accelerator QoS credits to assign */
-int usr_drc_count = 0;
+unsigned usr_drc_count = 0;
 
 /* user specified drc type to use */
 enum drc_type usr_drc_type = DRC_TYPE_NONE;
diff --git a/src/lparstat.c b/src/lparstat.c
index fe8b0fc..54d2bcd 100644
--- a/src/lparstat.c
+++ b/src/lparstat.c
@@ -134,7 +134,7 @@ static int assign_cpu_sysfs_fds(int threads_in_system)
 	char sysfs_file_path[SYSFS_PATH_MAX];
 
 	cpu_sysfs_fds =
-		(cpu_sysfs_fd*)calloc(sizeof(cpu_sysfs_fd), threads_in_system);
+		(cpu_sysfs_fd*)calloc(threads_in_system, sizeof(cpu_sysfs_fd));
 	if (!cpu_sysfs_fds) {
 		fprintf(stderr, "Failed to allocate memory for sysfs file descriptors\n");
 		return -1;
diff --git a/src/nvram.c b/src/nvram.c
index 1987c3d..7c40cf7 100644
--- a/src/nvram.c
+++ b/src/nvram.c
@@ -670,7 +670,7 @@ getsmallvalue(char *p, char *buf)
 static char *
 lookupfield(char *p)
 {
-    int i;
+    unsigned i;
 
     for (i = 0; (i < sizeof(descs) / sizeof(descs[0])); i++) {
 	if (strcmp(p, descs[i].name) == 0)
@@ -1181,7 +1181,7 @@ print_of_config_part(struct nvram *nvram, char *pname)
 {
     struct partition_header	*phead;
     char	*data;
-    int		i;
+    unsigned	i;
 
     phead = nvram_find_partition(nvram, 0, pname, NULL);
     if (phead == NULL) 
@@ -1223,7 +1223,8 @@ print_of_config(struct nvram *nvram, char *config_var, char *pname,
 {
     struct partition_header *phead;
     char *data, terminator;
-    int  i, varlen;
+    int  i;
+    size_t varlen;
     int  rc = -1;
 
     terminator = '\n';
diff --git a/src/ppc64_cpu.c b/src/ppc64_cpu.c
index ad9f4dc..d6f33c5 100644
--- a/src/ppc64_cpu.c
+++ b/src/ppc64_cpu.c
@@ -792,7 +792,7 @@ static void report_system_power_mode(void)
 static void setrlimit_open_files(void)
 {
 	struct rlimit old_rlim, new_rlim;
-	int new = threads_in_system + 8;
+	unsigned new = threads_in_system + 8;
 
 	getrlimit(RLIMIT_NOFILE, &old_rlim);
 
diff --git a/src/rtas_dbg.c b/src/rtas_dbg.c
index 6c7854a..a738113 100644
--- a/src/rtas_dbg.c
+++ b/src/rtas_dbg.c
@@ -182,7 +182,7 @@ struct rtas_token *get_rtas_token_by_name(char *name,
 	return NULL;
 }
 
-struct rtas_token *get_rtas_token_by_value(int value,
+struct rtas_token *get_rtas_token_by_value(unsigned value,
 					   struct rtas_token *tok_list)
 {
 	struct rtas_token *tok;
@@ -269,7 +269,7 @@ int main(int argc, char *argv[])
 	}
 
 	if ((dbg_arg[0] >= '0') && (dbg_arg[0] <= '9'))
-		tok = get_rtas_token_by_value(strtol(dbg_arg, NULL, 0),
+		tok = get_rtas_token_by_value(strtoul(dbg_arg, NULL, 0),
 					      tok_list);
 	else
 		tok = get_rtas_token_by_name(dbg_arg, tok_list);
diff --git a/src/sys_ident.c b/src/sys_ident.c
index 2c5c06b..20fe2e8 100644
--- a/src/sys_ident.c
+++ b/src/sys_ident.c
@@ -386,7 +386,7 @@ print_sys_part_id(void)
 
 	close(fd);
 
-	strncpy(tttt, model+4, 4);
+	memcpy(tttt, model+4, 4);
 	tttt[4] = '\0';
 
 	fd = open("/proc/device-tree/ibm,partition-no", O_RDONLY);
diff --git a/src/uesensor.c b/src/uesensor.c
index 0420137..ea17aff 100644
--- a/src/uesensor.c
+++ b/src/uesensor.c
@@ -422,6 +422,8 @@ main (int argc, char **argv)
 	}
 
 	if (text || numerical) {
+		unsigned i;
+
 		/* Print the status/value of all sensors */
 		fd = open(PATH_RTAS_SENSORS, O_RDONLY);