Merge tag 'nolibc-20251130-for-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/nolibc/linux-nolibc

Pull nolibc updates from Thomas Weißschuh:

 - Preparations to the use of nolibc in UML:
     - Cleanup of sparse warnings
     - Library mode without _start()
     - More consistency when disabling errno

 - Unconditional installation of all architecture support files

 - Always 64-bit wide ino_t and off_t

 - Various cleanups and bug fixes

* tag 'nolibc-20251130-for-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/nolibc/linux-nolibc: (25 commits)
  selftests/nolibc: error out on linker warnings
  selftests/nolibc: use lld to link loongarch binaries
  tools/nolibc: remove more __nolibc_enosys() fallbacks
  tools/nolibc: remove now superfluous overflow check in llseek
  tools/nolibc: use 64-bit off_t
  tools/nolibc: prefer the llseek syscall
  tools/nolibc: handle 64-bit off_t for llseek
  tools/nolibc: use 64-bit ino_t
  tools/nolibc: avoid using plain integer as NULL pointer
  tools/nolibc: add support for fchdir()
  tools/nolibc: clean up outdated comments in generic arch.h
  tools/nolibc: make the "headers" target install all supported archs
  tools/nolibc: add the more portable inttypes.h
  tools/nolibc: provide the portable sys/select.h
  tools/nolibc: add missing memchr() to string.h
  tools/nolibc: fix misleading help message regarding installation path
  tools/nolibc: add uio.h with readv and writev
  tools/nolibc: add option to disable runtime
  tools/nolibc: use __fallthrough__ rather than fallthrough
  tools/nolibc: implement %m if errno is not defined
  ...

3 files changed, 15 insertions, 1 deletions

diff --git a/tools/testing/selftests/nolibc/Makefile.nolibc b/tools/testing/selftests/nolibc/Makefile.nolibc
index 9416ae952e18..f9d43cbdc894 100644
--- a/tools/testing/selftests/nolibc/Makefile.nolibc
+++ b/tools/testing/selftests/nolibc/Makefile.nolibc
@@ -225,6 +225,7 @@ CFLAGS_mipsn32le = -EL -mabi=n32 -fPIC -march=mips64r2
 CFLAGS_mipsn32be = -EB -mabi=n32 -march=mips64r6
 CFLAGS_mips64le = -EL -mabi=64 -march=mips64r6
 CFLAGS_mips64be = -EB -mabi=64 -march=mips64r2
+CFLAGS_loongarch = $(if $(LLVM),-fuse-ld=lld)
 CFLAGS_sparc32 = $(call cc-option,-m32)
 CFLAGS_sh4 = -ml -m4
 ifeq ($(origin XARCH),command line)
diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index 29de21595fc9..3c5a226dad3a 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -25,6 +25,7 @@
 #include <sys/sysmacros.h>
 #include <sys/time.h>
 #include <sys/timerfd.h>
+#include <sys/uio.h>
 #include <sys/utsname.h>
 #include <sys/wait.h>
 #include <dirent.h>
@@ -1282,6 +1283,10 @@ int run_syscall(int min, int max)
 	int proc;
 	int test;
 	int tmp;
+	struct iovec iov_one = {
+		.iov_base = &tmp,
+		.iov_len = 1,
+	};
 	int ret = 0;
 	void *p1, *p2;
 	int has_gettid = 1;
@@ -1343,6 +1348,8 @@ int run_syscall(int min, int max)
 		CASE_TEST(dup3_0);            tmp = dup3(0, 100, 0);  EXPECT_SYSNE(1, tmp, -1); close(tmp); break;
 		CASE_TEST(dup3_m1);           tmp = dup3(-1, 100, 0); EXPECT_SYSER(1, tmp, -1, EBADF); if (tmp != -1) close(tmp); break;
 		CASE_TEST(execve_root);       EXPECT_SYSER(1, execve("/", (char*[]){ [0] = "/", [1] = NULL }, NULL), -1, EACCES); break;
+		CASE_TEST(fchdir_stdin);      EXPECT_SYSER(1, fchdir(STDIN_FILENO), -1, ENOTDIR); break;
+		CASE_TEST(fchdir_badfd);      EXPECT_SYSER(1, fchdir(-1), -1, EBADF); break;
 		CASE_TEST(file_stream);       EXPECT_SYSZR(1, test_file_stream()); break;
 		CASE_TEST(fork);              EXPECT_SYSZR(1, test_fork(FORK_STANDARD)); break;
 		CASE_TEST(getdents64_root);   EXPECT_SYSNE(1, test_getdents64("/"), -1); break;
@@ -1395,6 +1402,10 @@ int run_syscall(int min, int max)
 		CASE_TEST(waitpid_child);     EXPECT_SYSER(1, waitpid(getpid(), &tmp, WNOHANG), -1, ECHILD); break;
 		CASE_TEST(write_badf);        EXPECT_SYSER(1, write(-1, &tmp, 1), -1, EBADF); break;
 		CASE_TEST(write_zero);        EXPECT_SYSZR(1, write(1, &tmp, 0)); break;
+		CASE_TEST(readv_badf);        EXPECT_SYSER(1, readv(-1, &iov_one, 1), -1, EBADF); break;
+		CASE_TEST(readv_zero);        EXPECT_SYSZR(1, readv(1, NULL, 0)); break;
+		CASE_TEST(writev_badf);       EXPECT_SYSER(1, writev(-1, &iov_one, 1), -1, EBADF); break;
+		CASE_TEST(writev_zero);       EXPECT_SYSZR(1, writev(1, NULL, 0)); break;
 		CASE_TEST(syscall_noargs);    EXPECT_SYSEQ(1, syscall(__NR_getpid), getpid()); break;
 		CASE_TEST(syscall_args);      EXPECT_SYSER(1, syscall(__NR_statx, 0, NULL, 0, 0, NULL), -1, EFAULT); break;
 		CASE_TEST(namespace);         EXPECT_SYSZR(euid0 && proc, test_namespace()); break;
@@ -1540,6 +1551,8 @@ int run_stdlib(int min, int max)
 		CASE_TEST(abs);                     EXPECT_EQ(1, abs(-10), 10); break;
 		CASE_TEST(abs_noop);                EXPECT_EQ(1, abs(10), 10); break;
 		CASE_TEST(difftime);                EXPECT_ZR(1, test_difftime()); break;
+		CASE_TEST(memchr_foobar6_o);        EXPECT_STREQ(1, memchr("foobar", 'o', 6), "oobar"); break;
+		CASE_TEST(memchr_foobar3_b);        EXPECT_STRZR(1, memchr("foobar", 'b', 3)); break;
 
 		case __LINE__:
 			return ret; /* must be last */
diff --git a/tools/testing/selftests/nolibc/run-tests.sh b/tools/testing/selftests/nolibc/run-tests.sh
index 210abe715ed9..3917cfb8fdc4 100755
--- a/tools/testing/selftests/nolibc/run-tests.sh
+++ b/tools/testing/selftests/nolibc/run-tests.sh
@@ -169,7 +169,7 @@ test_arch() {
 	cross_compile=$(realpath "${download_location}gcc-${crosstool_version}-nolibc/${ct_arch}-${ct_abi}/bin/${ct_arch}-${ct_abi}-")
 	build_dir="${build_location}/${arch}"
 	if [ "$werror" -ne 0 ]; then
-		CFLAGS_EXTRA="$CFLAGS_EXTRA -Werror"
+		CFLAGS_EXTRA="$CFLAGS_EXTRA -Werror -Wl,--fatal-warnings"
 	fi
 	MAKE=(make -f Makefile.nolibc -j"${nproc}" XARCH="${arch}" CROSS_COMPILE="${cross_compile}" LLVM="${llvm}" O="${build_dir}")