Merge tag 'printk-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

Pull printk updates from Petr Mladek:

 - Fix printk ring buffer initialization and sanity checks

 - Workaround printf kunit test compilation with gcc < 12.1

 - Add IPv6 address printf format tests

 - Misc code and documentation cleanup

* tag 'printk-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printf: Compile the kunit test with DISABLE_BRANCH_PROFILING DISABLE_BRANCH_PROFILING
  lib/vsprintf: use bool for local decode variable
  lib/hexdump: print_hex_dump_bytes() calls print_hex_dump_debug()
  printk: ringbuffer: fix errors in comments
  printk_ringbuffer: Add sanity check for 0-size data
  printk_ringbuffer: Fix get_data() size sanity check
  printf: add IPv6 address format tests
  printk: Fix _DESCS_COUNT type for 64-bit systems

3 files changed, 26 insertions, 2 deletions

diff --git a/lib/tests/Makefile b/lib/tests/Makefile
index 05f74edbc62b..7e9c2fa52e35 100644
--- a/lib/tests/Makefile
+++ b/lib/tests/Makefile
@@ -40,6 +40,8 @@ obj-$(CONFIG_MEMCPY_KUNIT_TEST) += memcpy_kunit.o
 obj-$(CONFIG_MIN_HEAP_KUNIT_TEST) += min_heap_kunit.o
 CFLAGS_overflow_kunit.o = $(call cc-disable-warning, tautological-constant-out-of-range-compare)
 obj-$(CONFIG_OVERFLOW_KUNIT_TEST) += overflow_kunit.o
+# GCC < 12.1 can miscompile errptr() test when branch profiling is enabled.
+CFLAGS_printf_kunit.o += -DDISABLE_BRANCH_PROFILING
 obj-$(CONFIG_PRINTF_KUNIT_TEST) += printf_kunit.o
 obj-$(CONFIG_RANDSTRUCT_KUNIT_TEST) += randstruct_kunit.o
 obj-$(CONFIG_SCANF_KUNIT_TEST) += scanf_kunit.o
diff --git a/lib/tests/printf_kunit.c b/lib/tests/printf_kunit.c
index f6f21b445ece..bb70b9cddadd 100644
--- a/lib/tests/printf_kunit.c
+++ b/lib/tests/printf_kunit.c
@@ -17,6 +17,7 @@
 #include <linux/dcache.h>
 #include <linux/socket.h>
 #include <linux/in.h>
+#include <linux/in6.h>
 
 #include <linux/gfp.h>
 #include <linux/mm.h>
@@ -437,6 +438,27 @@ ip4(struct kunit *kunittest)
 static void
 ip6(struct kunit *kunittest)
 {
+	const struct in6_addr addr = {
+		.s6_addr = { 0x00, 0x01, 0x00, 0x02, 0x00, 0x03, 0x00, 0x04,
+			     0x00, 0x05, 0x00, 0x06, 0x00, 0x07, 0x00, 0x08 }
+	};
+	const struct in6_addr single_zero = {
+		.s6_addr = { 0x00, 0x01, 0x00, 0x00, 0x00, 0x03, 0x00, 0x04,
+			     0x00, 0x05, 0x00, 0x06, 0x00, 0x07, 0x00, 0x08 }
+	};
+	struct sockaddr_in6 sa = {
+		.sin6_family = AF_INET6,
+		.sin6_port = cpu_to_be16(12345),
+		.sin6_addr = addr,
+	};
+
+	test("00010002000300040005000600070008|0001:0002:0003:0004:0005:0006:0007:0008",
+	     "%pi6|%pI6", &addr, &addr);
+	test("00010002000300040005000600070008|0001:0002:0003:0004:0005:0006:0007:0008",
+	     "%piS|%pIS", &sa, &sa);
+	test("1:2:3:4:5:6:7:8", "%pI6c", &addr);
+	test("1:0:3:4:5:6:7:8", "%pI6c", &single_zero);
+	test("[1:2:3:4:5:6:7:8]:12345", "%pISpc", &sa);
 }
 
 static void
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 800b8ac49f53..9f359b31c8d1 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1107,7 +1107,7 @@ char *resource_string(char *buf, char *end, struct resource *res,
 		     2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
 
 	char *p = sym, *pend = sym + sizeof(sym);
-	int decode = (fmt[0] == 'R') ? 1 : 0;
+	bool decode = fmt[0] == 'R';
 	const struct printf_spec *specp;
 
 	if (check_pointer(&buf, end, res, spec))
@@ -1132,7 +1132,7 @@ char *resource_string(char *buf, char *end, struct resource *res,
 	} else {
 		p = string_nocheck(p, pend, "??? ", str_spec);
 		specp = &mem_spec;
-		decode = 0;
+		decode = false;
 	}
 	if (decode && res->flags & IORESOURCE_UNSET) {
 		p = string_nocheck(p, pend, "size ", str_spec);