Merge tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk

Pull printk updates from Petr Mladek:

 - Allow to print symbolic error names via new %pe modifier.

 - Use pr_warn() instead of the remaining pr_warning() calls. Fix
   formatting of the related lines.

 - Add VSPRINTF entry to MAINTAINERS.

* tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (32 commits)
  checkpatch: don't warn about new vsprintf pointer extension '%pe'
  MAINTAINERS: Add VSPRINTF
  tools lib api: Renaming pr_warning to pr_warn
  ASoC: samsung: Use pr_warn instead of pr_warning
  lib: cpu_rmap: Use pr_warn instead of pr_warning
  trace: Use pr_warn instead of pr_warning
  dma-debug: Use pr_warn instead of pr_warning
  vgacon: Use pr_warn instead of pr_warning
  fs: afs: Use pr_warn instead of pr_warning
  sh/intc: Use pr_warn instead of pr_warning
  scsi: Use pr_warn instead of pr_warning
  platform/x86: intel_oaktrail: Use pr_warn instead of pr_warning
  platform/x86: asus-laptop: Use pr_warn instead of pr_warning
  platform/x86: eeepc-laptop: Use pr_warn instead of pr_warning
  oprofile: Use pr_warn instead of pr_warning
  of: Use pr_warn instead of pr_warning
  macintosh: Use pr_warn instead of pr_warning
  idsn: Use pr_warn instead of pr_warning
  ide: Use pr_warn instead of pr_warning
  crypto: n2: Use pr_warn instead of pr_warning
  ...

6 files changed, 282 insertions, 1 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 6c1be6181e38..ecde997db751 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -164,6 +164,15 @@ config DYNAMIC_DEBUG
 	  See Documentation/admin-guide/dynamic-debug-howto.rst for additional
 	  information.
 
+config SYMBOLIC_ERRNAME
+	bool "Support symbolic error names in printf"
+	default y if PRINTK
+	help
+	  If you say Y here, the kernel's printf implementation will
+	  be able to print symbolic error names such as ENOSPC instead
+	  of the number 28. It makes the kernel image slightly larger
+	  (about 3KB), but can make the kernel logs easier to read.
+
 endmenu # "printk and dmesg options"
 
 menu "Compile-time checks and compiler options"
diff --git a/lib/Makefile b/lib/Makefile
index 890e581d00c4..3eea32105afc 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -183,6 +183,7 @@ lib-$(CONFIG_GENERIC_BUG) += bug.o
 obj-$(CONFIG_HAVE_ARCH_TRACEHOOK) += syscall.o
 
 obj-$(CONFIG_DYNAMIC_DEBUG) += dynamic_debug.o
+obj-$(CONFIG_SYMBOLIC_ERRNAME) += errname.o
 
 obj-$(CONFIG_NLATTR) += nlattr.o
 
diff --git a/lib/cpu_rmap.c b/lib/cpu_rmap.c
index 075f3788bbe4..f08d9c56f712 100644
--- a/lib/cpu_rmap.c
+++ b/lib/cpu_rmap.c
@@ -255,7 +255,7 @@ irq_cpu_rmap_notify(struct irq_affinity_notify *notify, const cpumask_t *mask)
 
 	rc = cpu_rmap_update(glue->rmap, glue->index, mask);
 	if (rc)
-		pr_warning("irq_cpu_rmap_notify: update failed: %d\n", rc);
+		pr_warn("irq_cpu_rmap_notify: update failed: %d\n", rc);
 }
 
 /**
diff --git a/lib/errname.c b/lib/errname.c
new file mode 100644
index 000000000000..0c4d3e66170e
--- /dev/null
+++ b/lib/errname.c
@@ -0,0 +1,223 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/build_bug.h>
+#include <linux/errno.h>
+#include <linux/errname.h>
+#include <linux/kernel.h>
+
+/*
+ * Ensure these tables do not accidentally become gigantic if some
+ * huge errno makes it in. On most architectures, the first table will
+ * only have about 140 entries, but mips and parisc have more sparsely
+ * allocated errnos (with EHWPOISON = 257 on parisc, and EDQUOT = 1133
+ * on mips), so this wastes a bit of space on those - though we
+ * special case the EDQUOT case.
+ */
+#define E(err) [err + BUILD_BUG_ON_ZERO(err <= 0 || err > 300)] = "-" #err
+static const char *names_0[] = {
+	E(E2BIG),
+	E(EACCES),
+	E(EADDRINUSE),
+	E(EADDRNOTAVAIL),
+	E(EADV),
+	E(EAFNOSUPPORT),
+	E(EALREADY),
+	E(EBADE),
+	E(EBADF),
+	E(EBADFD),
+	E(EBADMSG),
+	E(EBADR),
+	E(EBADRQC),
+	E(EBADSLT),
+	E(EBFONT),
+	E(EBUSY),
+#ifdef ECANCELLED
+	E(ECANCELLED),
+#endif
+	E(ECHILD),
+	E(ECHRNG),
+	E(ECOMM),
+	E(ECONNABORTED),
+	E(ECONNRESET),
+	E(EDEADLOCK),
+	E(EDESTADDRREQ),
+	E(EDOM),
+	E(EDOTDOT),
+#ifndef CONFIG_MIPS
+	E(EDQUOT),
+#endif
+	E(EEXIST),
+	E(EFAULT),
+	E(EFBIG),
+	E(EHOSTDOWN),
+	E(EHOSTUNREACH),
+	E(EHWPOISON),
+	E(EIDRM),
+	E(EILSEQ),
+#ifdef EINIT
+	E(EINIT),
+#endif
+	E(EINPROGRESS),
+	E(EINTR),
+	E(EINVAL),
+	E(EIO),
+	E(EISCONN),
+	E(EISDIR),
+	E(EISNAM),
+	E(EKEYEXPIRED),
+	E(EKEYREJECTED),
+	E(EKEYREVOKED),
+	E(EL2HLT),
+	E(EL2NSYNC),
+	E(EL3HLT),
+	E(EL3RST),
+	E(ELIBACC),
+	E(ELIBBAD),
+	E(ELIBEXEC),
+	E(ELIBMAX),
+	E(ELIBSCN),
+	E(ELNRNG),
+	E(ELOOP),
+	E(EMEDIUMTYPE),
+	E(EMFILE),
+	E(EMLINK),
+	E(EMSGSIZE),
+	E(EMULTIHOP),
+	E(ENAMETOOLONG),
+	E(ENAVAIL),
+	E(ENETDOWN),
+	E(ENETRESET),
+	E(ENETUNREACH),
+	E(ENFILE),
+	E(ENOANO),
+	E(ENOBUFS),
+	E(ENOCSI),
+	E(ENODATA),
+	E(ENODEV),
+	E(ENOENT),
+	E(ENOEXEC),
+	E(ENOKEY),
+	E(ENOLCK),
+	E(ENOLINK),
+	E(ENOMEDIUM),
+	E(ENOMEM),
+	E(ENOMSG),
+	E(ENONET),
+	E(ENOPKG),
+	E(ENOPROTOOPT),
+	E(ENOSPC),
+	E(ENOSR),
+	E(ENOSTR),
+#ifdef ENOSYM
+	E(ENOSYM),
+#endif
+	E(ENOSYS),
+	E(ENOTBLK),
+	E(ENOTCONN),
+	E(ENOTDIR),
+	E(ENOTEMPTY),
+	E(ENOTNAM),
+	E(ENOTRECOVERABLE),
+	E(ENOTSOCK),
+	E(ENOTTY),
+	E(ENOTUNIQ),
+	E(ENXIO),
+	E(EOPNOTSUPP),
+	E(EOVERFLOW),
+	E(EOWNERDEAD),
+	E(EPERM),
+	E(EPFNOSUPPORT),
+	E(EPIPE),
+#ifdef EPROCLIM
+	E(EPROCLIM),
+#endif
+	E(EPROTO),
+	E(EPROTONOSUPPORT),
+	E(EPROTOTYPE),
+	E(ERANGE),
+	E(EREMCHG),
+#ifdef EREMDEV
+	E(EREMDEV),
+#endif
+	E(EREMOTE),
+	E(EREMOTEIO),
+#ifdef EREMOTERELEASE
+	E(EREMOTERELEASE),
+#endif
+	E(ERESTART),
+	E(ERFKILL),
+	E(EROFS),
+#ifdef ERREMOTE
+	E(ERREMOTE),
+#endif
+	E(ESHUTDOWN),
+	E(ESOCKTNOSUPPORT),
+	E(ESPIPE),
+	E(ESRCH),
+	E(ESRMNT),
+	E(ESTALE),
+	E(ESTRPIPE),
+	E(ETIME),
+	E(ETIMEDOUT),
+	E(ETOOMANYREFS),
+	E(ETXTBSY),
+	E(EUCLEAN),
+	E(EUNATCH),
+	E(EUSERS),
+	E(EXDEV),
+	E(EXFULL),
+
+	E(ECANCELED), /* ECANCELLED */
+	E(EAGAIN), /* EWOULDBLOCK */
+	E(ECONNREFUSED), /* EREFUSED */
+	E(EDEADLK), /* EDEADLOCK */
+};
+#undef E
+
+#define E(err) [err - 512 + BUILD_BUG_ON_ZERO(err < 512 || err > 550)] = "-" #err
+static const char *names_512[] = {
+	E(ERESTARTSYS),
+	E(ERESTARTNOINTR),
+	E(ERESTARTNOHAND),
+	E(ENOIOCTLCMD),
+	E(ERESTART_RESTARTBLOCK),
+	E(EPROBE_DEFER),
+	E(EOPENSTALE),
+	E(ENOPARAM),
+
+	E(EBADHANDLE),
+	E(ENOTSYNC),
+	E(EBADCOOKIE),
+	E(ENOTSUPP),
+	E(ETOOSMALL),
+	E(ESERVERFAULT),
+	E(EBADTYPE),
+	E(EJUKEBOX),
+	E(EIOCBQUEUED),
+	E(ERECALLCONFLICT),
+};
+#undef E
+
+static const char *__errname(unsigned err)
+{
+	if (err < ARRAY_SIZE(names_0))
+		return names_0[err];
+	if (err >= 512 && err - 512 < ARRAY_SIZE(names_512))
+		return names_512[err - 512];
+	/* But why? */
+	if (IS_ENABLED(CONFIG_MIPS) && err == EDQUOT) /* 1133 */
+		return "-EDQUOT";
+	return NULL;
+}
+
+/*
+ * errname(EIO) -> "EIO"
+ * errname(-EIO) -> "-EIO"
+ */
+const char *errname(int err)
+{
+	const char *name = __errname(abs(err));
+	if (!name)
+		return NULL;
+
+	return err > 0 ? name + 1 : name;
+}
diff --git a/lib/test_printf.c b/lib/test_printf.c
index 5d94cbff2120..030daeb4fe21 100644
--- a/lib/test_printf.c
+++ b/lib/test_printf.c
@@ -594,6 +594,26 @@ flags(void)
 }
 
 static void __init
+errptr(void)
+{
+	test("-1234", "%pe", ERR_PTR(-1234));
+
+	/* Check that %pe with a non-ERR_PTR gets treated as ordinary %p. */
+	BUILD_BUG_ON(IS_ERR(PTR));
+	test_hashed("%pe", PTR);
+
+#ifdef CONFIG_SYMBOLIC_ERRNAME
+	test("(-ENOTSOCK)", "(%pe)", ERR_PTR(-ENOTSOCK));
+	test("(-EAGAIN)", "(%pe)", ERR_PTR(-EAGAIN));
+	BUILD_BUG_ON(EAGAIN != EWOULDBLOCK);
+	test("(-EAGAIN)", "(%pe)", ERR_PTR(-EWOULDBLOCK));
+	test("[-EIO    ]", "[%-8pe]", ERR_PTR(-EIO));
+	test("[    -EIO]", "[%8pe]", ERR_PTR(-EIO));
+	test("-EPROBE_DEFER", "%pe", ERR_PTR(-EPROBE_DEFER));
+#endif
+}
+
+static void __init
 test_pointer(void)
 {
 	plain();
@@ -615,6 +635,7 @@ test_pointer(void)
 	bitmap();
 	netdev_features();
 	flags();
+	errptr();
 }
 
 static void __init selftest(void)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index e78017a3e1bd..b54d252b398e 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -21,6 +21,7 @@
 #include <linux/build_bug.h>
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
+#include <linux/errname.h>
 #include <linux/module.h>	/* for KSYM_SYMBOL_LEN */
 #include <linux/types.h>
 #include <linux/string.h>
@@ -613,6 +614,25 @@ static char *string_nocheck(char *buf, char *end, const char *s,
 	return widen_string(buf, len, end, spec);
 }
 
+static char *err_ptr(char *buf, char *end, void *ptr,
+		     struct printf_spec spec)
+{
+	int err = PTR_ERR(ptr);
+	const char *sym = errname(err);
+
+	if (sym)
+		return string_nocheck(buf, end, sym, spec);
+
+	/*
+	 * Somebody passed ERR_PTR(-1234) or some other non-existing
+	 * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to
+	 * printing it as its decimal representation.
+	 */
+	spec.flags |= SIGN;
+	spec.base = 10;
+	return number(buf, end, err, spec);
+}
+
 /* Be careful: error messages must fit into the given buffer. */
 static char *error_string(char *buf, char *end, const char *s,
 			  struct printf_spec spec)
@@ -2187,6 +2207,11 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 		return kobject_string(buf, end, ptr, spec, fmt);
 	case 'x':
 		return pointer_string(buf, end, ptr, spec);
+	case 'e':
+		/* %pe with a non-ERR_PTR gets treated as plain %p */
+		if (!IS_ERR(ptr))
+			break;
+		return err_ptr(buf, end, ptr, spec);
 	}
 
 	/* default is to _not_ leak addresses, hash before printing */
@@ -2823,6 +2848,7 @@ int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
 			case 'f':
 			case 'x':
 			case 'K':
+			case 'e':
 				save_arg(void *);
 				break;
 			default:
@@ -2999,6 +3025,7 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
 			case 'f':
 			case 'x':
 			case 'K':
+			case 'e':
 				process = true;
 				break;
 			default: