Merge tag 'nolibc.2023.06.22a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull nolibc updates from Paul McKenney:

 - Add stackprotector support

 - Fix RISC-V load-store instruction syntax to support 32-bit binaries,
   plus fixes for generic 32-bit support

 - Fix use of s390 sys_fork()

 - Add my_syscall6() for ARM

 - Support different platforms having different errno definitions

 - Fix ppoll/ppoll_time64 arguments (add the fifth argument)

 - Force use of little endian on MIPS

 - Improved testing, for example, better handling of different compilers
   and compiler versions, comparing nolibc behavior to that of libc, and
   additional test cases

 - Improve syntax and header ordering

 - Use existing <linux/reboot.h> instead of redefining constants

 - Add syscall()

* tag 'nolibc.2023.06.22a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (53 commits)
  selftests/nolibc: make sure gcc always use little endian on MIPS
  selftests/nolibc: also count skipped and failed tests in output
  selftests/nolibc: add new gettimeofday test cases
  selftests/nolibc: remove gettimeofday_bad1/2 completely
  selftests/nolibc: support two errnos with EXPECT_SYSER2()
  tools/nolibc: open: fix up compile warning for arm
  tools/nolibc: arm: add missing my_syscall6
  selftests/nolibc: use INT_MAX instead of __INT_MAX__
  selftests/nolibc: not include limits.h for nolibc
  selftests/nolibc: fix up compile warning with glibc on x86_64
  selftests/nolibc: allow specify extra arguments for qemu
  selftests/nolibc: remove test gettimeofday_null
  tools/nolibc: ensure fast64 integer types have 64 bits
  selftests/nolibc: test_fork: fix up duplicated print
  tools/nolibc: ppoll/ppoll_time64: add a missing argument
  selftests/nolibc: remove the duplicated gettimeofday_bad2
  selftests/nolibc: print name instead of number for EOVERFLOW
  tools/nolibc: support nanoseconds in stat()
  selftests/nolibc: prevent coredumps during test execution
  tools/nolibc: add support for prctl()
  ...

23 files changed, 704 insertions, 313 deletions

diff --git a/tools/include/nolibc/Makefile b/tools/include/nolibc/Makefile
index 9839feafd38a14..64d67b080744e6 100644
--- a/tools/include/nolibc/Makefile
+++ b/tools/include/nolibc/Makefile
@@ -25,8 +25,23 @@ endif
 
 nolibc_arch := $(patsubst arm64,aarch64,$(ARCH))
 arch_file := arch-$(nolibc_arch).h
-all_files := ctype.h errno.h nolibc.h signal.h stackprotector.h std.h stdint.h \
-             stdio.h stdlib.h string.h sys.h time.h types.h unistd.h
+all_files := \
+		compiler.h \
+		ctype.h \
+		errno.h \
+		nolibc.h \
+		signal.h \
+		stackprotector.h \
+		std.h \
+		stdint.h \
+		stdlib.h \
+		string.h \
+		sys.h \
+		time.h \
+		types.h \
+		unistd.h \
+		stdio.h \
+
 
 # install all headers needed to support a bare-metal compiler
 all: headers
diff --git a/tools/include/nolibc/arch-aarch64.h b/tools/include/nolibc/arch-aarch64.h
index 383baddef70191..11f294a406b7c6 100644
--- a/tools/include/nolibc/arch-aarch64.h
+++ b/tools/include/nolibc/arch-aarch64.h
@@ -7,6 +7,8 @@
 #ifndef _NOLIBC_ARCH_AARCH64_H
 #define _NOLIBC_ARCH_AARCH64_H
 
+#include "compiler.h"
+
 /* The struct returned by the newfstatat() syscall. Differs slightly from the
  * x86_64's stat one by field ordering, so be careful.
  */
@@ -173,27 +175,30 @@ char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
 /* startup code */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
 {
 	__asm__ volatile (
-		"ldr x0, [sp]\n"     // argc (x0) was in the stack
-		"add x1, sp, 8\n"    // argv (x1) = sp
-		"lsl x2, x0, 3\n"    // envp (x2) = 8*argc ...
-		"add x2, x2, 8\n"    //           + 8 (skip null)
-		"add x2, x2, x1\n"   //           + argv
-		"adrp x3, environ\n"          // x3 = &environ (high bits)
-		"str x2, [x3, #:lo12:environ]\n" // store envp into environ
-		"mov x4, x2\n"       // search for auxv (follows NULL after last env)
+#ifdef _NOLIBC_STACKPROTECTOR
+		"bl __stack_chk_init\n"   /* initialize stack protector                     */
+#endif
+		"ldr x0, [sp]\n"     /* argc (x0) was in the stack                          */
+		"add x1, sp, 8\n"    /* argv (x1) = sp                                      */
+		"lsl x2, x0, 3\n"    /* envp (x2) = 8*argc ...                              */
+		"add x2, x2, 8\n"    /*           + 8 (skip null)                           */
+		"add x2, x2, x1\n"   /*           + argv                                    */
+		"adrp x3, environ\n"          /* x3 = &environ (high bits)                  */
+		"str x2, [x3, #:lo12:environ]\n" /* store envp into environ                 */
+		"mov x4, x2\n"       /* search for auxv (follows NULL after last env)       */
 		"0:\n"
-		"ldr x5, [x4], 8\n"  // x5 = *x4; x4 += 8
-		"cbnz x5, 0b\n"      // and stop at NULL after last env
-		"adrp x3, _auxv\n"   // x3 = &_auxv (high bits)
-		"str x4, [x3, #:lo12:_auxv]\n" // store x4 into _auxv
-		"and sp, x1, -16\n"  // sp must be 16-byte aligned in the callee
-		"bl main\n"          // main() returns the status code, we'll exit with it.
-		"mov x8, 93\n"       // NR_exit == 93
+		"ldr x5, [x4], 8\n"  /* x5 = *x4; x4 += 8                                   */
+		"cbnz x5, 0b\n"      /* and stop at NULL after last env                     */
+		"adrp x3, _auxv\n"   /* x3 = &_auxv (high bits)                             */
+		"str x4, [x3, #:lo12:_auxv]\n" /* store x4 into _auxv                       */
+		"and sp, x1, -16\n"  /* sp must be 16-byte aligned in the callee            */
+		"bl main\n"          /* main() returns the status code, we'll exit with it. */
+		"mov x8, 93\n"       /* NR_exit == 93                                       */
 		"svc #0\n"
 	);
 	__builtin_unreachable();
 }
-#endif // _NOLIBC_ARCH_AARCH64_H
+#endif /* _NOLIBC_ARCH_AARCH64_H */
diff --git a/tools/include/nolibc/arch-arm.h b/tools/include/nolibc/arch-arm.h
index 42499f23e73c5c..ca4c669874973e 100644
--- a/tools/include/nolibc/arch-arm.h
+++ b/tools/include/nolibc/arch-arm.h
@@ -7,6 +7,8 @@
 #ifndef _NOLIBC_ARCH_ARM_H
 #define _NOLIBC_ARCH_ARM_H
 
+#include "compiler.h"
+
 /* The struct returned by the stat() syscall, 32-bit only, the syscall returns
  * exactly 56 bytes (stops before the unused array). In big endian, the format
  * differs as devices are returned as short only.
@@ -196,41 +198,67 @@ struct sys_stat_struct {
 	_arg1;                                                                \
 })
 
+#define my_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6)                  \
+({                                                                            \
+	register long _num  __asm__(_NOLIBC_SYSCALL_REG) = (num);             \
+	register long _arg1 __asm__ ("r0") = (long)(arg1);                    \
+	register long _arg2 __asm__ ("r1") = (long)(arg2);                    \
+	register long _arg3 __asm__ ("r2") = (long)(arg3);                    \
+	register long _arg4 __asm__ ("r3") = (long)(arg4);                    \
+	register long _arg5 __asm__ ("r4") = (long)(arg5);                    \
+	register long _arg6 __asm__ ("r5") = (long)(arg6);                    \
+	                                                                      \
+	__asm__  volatile (                                                   \
+		_NOLIBC_THUMB_SET_R7                                          \
+		"svc #0\n"                                                    \
+		_NOLIBC_THUMB_RESTORE_R7                                      \
+		: "=r"(_arg1), "=r" (_num)                                    \
+		: "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \
+		  "r"(_arg6), "r"(_num)                                       \
+		: "memory", "cc", "lr"                                        \
+	);                                                                    \
+	_arg1;                                                                \
+})
+
+
 char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
 /* startup code */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
 {
 	__asm__ volatile (
-		"pop {%r0}\n"                 // argc was in the stack
-		"mov %r1, %sp\n"              // argv = sp
+#ifdef _NOLIBC_STACKPROTECTOR
+		"bl __stack_chk_init\n"       /* initialize stack protector                          */
+#endif
+		"pop {%r0}\n"                 /* argc was in the stack                               */
+		"mov %r1, %sp\n"              /* argv = sp                                           */
 
-		"add %r2, %r0, $1\n"          // envp = (argc + 1) ...
-		"lsl %r2, %r2, $2\n"          //        * 4        ...
-		"add %r2, %r2, %r1\n"         //        + argv
-		"ldr %r3, 1f\n"               // r3 = &environ (see below)
-		"str %r2, [r3]\n"             // store envp into environ
+		"add %r2, %r0, $1\n"          /* envp = (argc + 1) ...                               */
+		"lsl %r2, %r2, $2\n"          /*        * 4        ...                               */
+		"add %r2, %r2, %r1\n"         /*        + argv                                       */
+		"ldr %r3, 1f\n"               /* r3 = &environ (see below)                           */
+		"str %r2, [r3]\n"             /* store envp into environ                             */
 
-		"mov r4, r2\n"                // search for auxv (follows NULL after last env)
+		"mov r4, r2\n"                /* search for auxv (follows NULL after last env)       */
 		"0:\n"
-		"mov r5, r4\n"                // r5 = r4
-		"add r4, r4, #4\n"            // r4 += 4
-		"ldr r5,[r5]\n"               // r5 = *r5 = *(r4-4)
-		"cmp r5, #0\n"                // and stop at NULL after last env
+		"mov r5, r4\n"                /* r5 = r4                                             */
+		"add r4, r4, #4\n"            /* r4 += 4                                             */
+		"ldr r5,[r5]\n"               /* r5 = *r5 = *(r4-4)                                  */
+		"cmp r5, #0\n"                /* and stop at NULL after last env                     */
 		"bne 0b\n"
-		"ldr %r3, 2f\n"               // r3 = &_auxv (low bits)
-		"str r4, [r3]\n"              // store r4 into _auxv
+		"ldr %r3, 2f\n"               /* r3 = &_auxv (low bits)                              */
+		"str r4, [r3]\n"              /* store r4 into _auxv                                 */
 
-		"mov %r3, $8\n"               // AAPCS : sp must be 8-byte aligned in the
-		"neg %r3, %r3\n"              //         callee, and bl doesn't push (lr=pc)
-		"and %r3, %r3, %r1\n"         // so we do sp = r1(=sp) & r3(=-8);
-		"mov %sp, %r3\n"              //
+		"mov %r3, $8\n"               /* AAPCS : sp must be 8-byte aligned in the            */
+		"neg %r3, %r3\n"              /*         callee, and bl doesn't push (lr=pc)         */
+		"and %r3, %r3, %r1\n"         /* so we do sp = r1(=sp) & r3(=-8);                    */
+		"mov %sp, %r3\n"
 
-		"bl main\n"                   // main() returns the status code, we'll exit with it.
-		"movs r7, $1\n"               // NR_exit == 1
+		"bl main\n"                   /* main() returns the status code, we'll exit with it. */
+		"movs r7, $1\n"               /* NR_exit == 1                                        */
 		"svc $0x00\n"
-		".align 2\n"                  // below are the pointers to a few variables
+		".align 2\n"                  /* below are the pointers to a few variables           */
 		"1:\n"
 		".word environ\n"
 		"2:\n"
@@ -239,4 +267,4 @@ void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
 	__builtin_unreachable();
 }
 
-#endif // _NOLIBC_ARCH_ARM_H
+#endif /* _NOLIBC_ARCH_ARM_H */
diff --git a/tools/include/nolibc/arch-i386.h b/tools/include/nolibc/arch-i386.h
index 2d98d78fd3f3a6..3d672d925e9e26 100644
--- a/tools/include/nolibc/arch-i386.h
+++ b/tools/include/nolibc/arch-i386.h
@@ -7,6 +7,8 @@
 #ifndef _NOLIBC_ARCH_I386_H
 #define _NOLIBC_ARCH_I386_H
 
+#include "compiler.h"
+
 /* The struct returned by the stat() syscall, 32-bit only, the syscall returns
  * exactly 56 bytes (stops before the unused array).
  */
@@ -181,8 +183,6 @@ struct sys_stat_struct {
 char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
-#define __ARCH_SUPPORTS_STACK_PROTECTOR
-
 /* startup code */
 /*
  * i386 System V ABI mandates:
@@ -190,35 +190,35 @@ const unsigned long *_auxv __attribute__((weak));
  * 2) The deepest stack frame should be set to zero
  *
  */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"),no_stack_protector)) _start(void)
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
 {
 	__asm__ volatile (
-#ifdef NOLIBC_STACKPROTECTOR
-		"call __stack_chk_init\n"   // initialize stack protector
+#ifdef _NOLIBC_STACKPROTECTOR
+		"call __stack_chk_init\n"   /* initialize stack protector                    */
 #endif
-		"pop %eax\n"                // argc   (first arg, %eax)
-		"mov %esp, %ebx\n"          // argv[] (second arg, %ebx)
-		"lea 4(%ebx,%eax,4),%ecx\n" // then a NULL then envp (third arg, %ecx)
-		"mov %ecx, environ\n"       // save environ
-		"xor %ebp, %ebp\n"          // zero the stack frame
-		"mov %ecx, %edx\n"          // search for auxv (follows NULL after last env)
+		"pop %eax\n"                /* argc   (first arg, %eax)                      */
+		"mov %esp, %ebx\n"          /* argv[] (second arg, %ebx)                     */
+		"lea 4(%ebx,%eax,4),%ecx\n" /* then a NULL then envp (third arg, %ecx)       */
+		"mov %ecx, environ\n"       /* save environ                                  */
+		"xor %ebp, %ebp\n"          /* zero the stack frame                          */
+		"mov %ecx, %edx\n"          /* search for auxv (follows NULL after last env) */
 		"0:\n"
-		"add $4, %edx\n"            // search for auxv using edx, it follows the
-		"cmp -4(%edx), %ebp\n"      // ... NULL after last env (ebp is zero here)
+		"add $4, %edx\n"            /* search for auxv using edx, it follows the     */
+		"cmp -4(%edx), %ebp\n"      /* ... NULL after last env (ebp is zero here)    */
 		"jnz 0b\n"
-		"mov %edx, _auxv\n"         // save it into _auxv
-		"and $-16, %esp\n"          // x86 ABI : esp must be 16-byte aligned before
-		"sub $4, %esp\n"            // the call instruction (args are aligned)
-		"push %ecx\n"               // push all registers on the stack so that we
-		"push %ebx\n"               // support both regparm and plain stack modes
+		"mov %edx, _auxv\n"         /* save it into _auxv                            */
+		"and $-16, %esp\n"          /* x86 ABI : esp must be 16-byte aligned before  */
+		"sub $4, %esp\n"            /* the call instruction (args are aligned)       */
+		"push %ecx\n"               /* push all registers on the stack so that we    */
+		"push %ebx\n"               /* support both regparm and plain stack modes    */
 		"push %eax\n"
-		"call main\n"               // main() returns the status code in %eax
-		"mov %eax, %ebx\n"          // retrieve exit code (32-bit int)
-		"movl $1, %eax\n"           // NR_exit == 1
-		"int $0x80\n"               // exit now
-		"hlt\n"                     // ensure it does not
+		"call main\n"               /* main() returns the status code in %eax        */
+		"mov %eax, %ebx\n"          /* retrieve exit code (32-bit int)               */
+		"movl $1, %eax\n"           /* NR_exit == 1                                  */
+		"int $0x80\n"               /* exit now                                      */
+		"hlt\n"                     /* ensure it does not                            */
 	);
 	__builtin_unreachable();
 }
 
-#endif // _NOLIBC_ARCH_I386_H
+#endif /* _NOLIBC_ARCH_I386_H */
diff --git a/tools/include/nolibc/arch-loongarch.h b/tools/include/nolibc/arch-loongarch.h
index 029ee3cd6bafa3..ad3f266e709303 100644
--- a/tools/include/nolibc/arch-loongarch.h
+++ b/tools/include/nolibc/arch-loongarch.h
@@ -7,6 +7,8 @@
 #ifndef _NOLIBC_ARCH_LOONGARCH_H
 #define _NOLIBC_ARCH_LOONGARCH_H
 
+#include "compiler.h"
+
 /* Syscalls for LoongArch :
  *   - stack is 16-byte aligned
  *   - syscall number is passed in a7
@@ -158,7 +160,7 @@ const unsigned long *_auxv __attribute__((weak));
 #define LONG_ADDI    "addi.w"
 #define LONG_SLL     "slli.w"
 #define LONG_BSTRINS "bstrins.w"
-#else // __loongarch_grlen == 64
+#else /* __loongarch_grlen == 64 */
 #define LONGLOG      "3"
 #define SZREG        "8"
 #define REG_L        "ld.d"
@@ -170,31 +172,34 @@ const unsigned long *_auxv __attribute__((weak));
 #endif
 
 /* startup code */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
 {
 	__asm__ volatile (
-		REG_L        " $a0, $sp, 0\n"         // argc (a0) was in the stack
-		LONG_ADDI    " $a1, $sp, "SZREG"\n"   // argv (a1) = sp + SZREG
-		LONG_SLL     " $a2, $a0, "LONGLOG"\n" // envp (a2) = SZREG*argc ...
-		LONG_ADDI    " $a2, $a2, "SZREG"\n"   //             + SZREG (skip null)
-		LONG_ADD     " $a2, $a2, $a1\n"       //             + argv
-
-		"move          $a3, $a2\n"            // iterate a3 over envp to find auxv (after NULL)
-		"0:\n"                                // do {
-		REG_L        " $a4, $a3, 0\n"         //   a4 = *a3;
-		LONG_ADDI    " $a3, $a3, "SZREG"\n"   //   a3 += sizeof(void*);
-		"bne           $a4, $zero, 0b\n"      // } while (a4);
-		"la.pcrel      $a4, _auxv\n"          // a4 = &_auxv
-		LONG_S       " $a3, $a4, 0\n"         // store a3 into _auxv
-
-		"la.pcrel      $a3, environ\n"        // a3 = &environ
-		LONG_S       " $a2, $a3, 0\n"         // store envp(a2) into environ
-		LONG_BSTRINS " $sp, $zero, 3, 0\n"    // sp must be 16-byte aligned
-		"bl            main\n"                // main() returns the status code, we'll exit with it.
-		"li.w          $a7, 93\n"             // NR_exit == 93
+#ifdef _NOLIBC_STACKPROTECTOR
+		"bl __stack_chk_init\n"               /* initialize stack protector                          */
+#endif
+		REG_L        " $a0, $sp, 0\n"         /* argc (a0) was in the stack                          */
+		LONG_ADDI    " $a1, $sp, "SZREG"\n"   /* argv (a1) = sp + SZREG                              */
+		LONG_SLL     " $a2, $a0, "LONGLOG"\n" /* envp (a2) = SZREG*argc ...                          */
+		LONG_ADDI    " $a2, $a2, "SZREG"\n"   /*             + SZREG (skip null)                     */
+		LONG_ADD     " $a2, $a2, $a1\n"       /*             + argv                                  */
+
+		"move          $a3, $a2\n"            /* iterate a3 over envp to find auxv (after NULL)      */
+		"0:\n"                                /* do {                                                */
+		REG_L        " $a4, $a3, 0\n"         /*   a4 = *a3;                                         */
+		LONG_ADDI    " $a3, $a3, "SZREG"\n"   /*   a3 += sizeof(void*);                              */
+		"bne           $a4, $zero, 0b\n"      /* } while (a4);                                       */
+		"la.pcrel      $a4, _auxv\n"          /* a4 = &_auxv                                         */
+		LONG_S       " $a3, $a4, 0\n"         /* store a3 into _auxv                                 */
+
+		"la.pcrel      $a3, environ\n"        /* a3 = &environ                                       */
+		LONG_S       " $a2, $a3, 0\n"         /* store envp(a2) into environ                         */
+		LONG_BSTRINS " $sp, $zero, 3, 0\n"    /* sp must be 16-byte aligned                          */
+		"bl            main\n"                /* main() returns the status code, we'll exit with it. */
+		"li.w          $a7, 93\n"             /* NR_exit == 93                                       */
 		"syscall       0\n"
 	);
 	__builtin_unreachable();
 }
 
-#endif // _NOLIBC_ARCH_LOONGARCH_H
+#endif /* _NOLIBC_ARCH_LOONGARCH_H */
diff --git a/tools/include/nolibc/arch-mips.h b/tools/include/nolibc/arch-mips.h
index bf83432d23ed31..db24e0837a39bf 100644
--- a/tools/include/nolibc/arch-mips.h
+++ b/tools/include/nolibc/arch-mips.h
@@ -7,6 +7,8 @@
 #ifndef _NOLIBC_ARCH_MIPS_H
 #define _NOLIBC_ARCH_MIPS_H
 
+#include "compiler.h"
+
 /* The struct returned by the stat() syscall. 88 bytes are returned by the
  * syscall.
  */
@@ -180,45 +182,49 @@ char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
 /* startup code, note that it's called __start on MIPS */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __start(void)
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector __start(void)
 {
 	__asm__ volatile (
-		//".set nomips16\n"
+		/*".set nomips16\n"*/
 		".set push\n"
 		".set    noreorder\n"
 		".option pic0\n"
-		//".ent __start\n"
-		//"__start:\n"
-		"lw $a0,($sp)\n"        // argc was in the stack
-		"addiu  $a1, $sp, 4\n"  // argv = sp + 4
-		"sll $a2, $a0, 2\n"     // a2 = argc * 4
-		"add   $a2, $a2, $a1\n" // envp = argv + 4*argc ...
-		"addiu $a2, $a2, 4\n"   //        ... + 4
-		"lui $a3, %hi(environ)\n"     // load environ into a3 (hi)
-		"addiu $a3, %lo(environ)\n"   // load environ into a3 (lo)
-		"sw $a2,($a3)\n"              // store envp(a2) into environ
-
-		"move $t0, $a2\n"             // iterate t0 over envp, look for NULL
-		"0:"                          // do {
-		"lw $a3, ($t0)\n"             //   a3=*(t0);
-		"bne $a3, $0, 0b\n"           // } while (a3);
-		"addiu $t0, $t0, 4\n"         // delayed slot: t0+=4;
-		"lui $a3, %hi(_auxv)\n"       // load _auxv into a3 (hi)
-		"addiu $a3, %lo(_auxv)\n"     // load _auxv into a3 (lo)
-		"sw $t0, ($a3)\n"             // store t0 into _auxv
+#ifdef _NOLIBC_STACKPROTECTOR
+		"jal __stack_chk_init\n" /* initialize stack protector                         */
+		"nop\n"                  /* delayed slot                                       */
+#endif
+		/*".ent __start\n"*/
+		/*"__start:\n"*/
+		"lw $a0,($sp)\n"        /* argc was in the stack                               */
+		"addiu  $a1, $sp, 4\n"  /* argv = sp + 4                                       */
+		"sll $a2, $a0, 2\n"     /* a2 = argc * 4                                       */
+		"add   $a2, $a2, $a1\n" /* envp = argv + 4*argc ...                            */
+		"addiu $a2, $a2, 4\n"   /*        ... + 4                                      */
+		"lui $a3, %hi(environ)\n"     /* load environ into a3 (hi)                     */
+		"addiu $a3, %lo(environ)\n"   /* load environ into a3 (lo)                     */
+		"sw $a2,($a3)\n"              /* store envp(a2) into environ                   */
+
+		"move $t0, $a2\n"             /* iterate t0 over envp, look for NULL           */
+		"0:"                          /* do {                                          */
+		"lw $a3, ($t0)\n"             /*   a3=*(t0);                                   */
+		"bne $a3, $0, 0b\n"           /* } while (a3);                                 */
+		"addiu $t0, $t0, 4\n"         /* delayed slot: t0+=4;                          */
+		"lui $a3, %hi(_auxv)\n"       /* load _auxv into a3 (hi)                       */
+		"addiu $a3, %lo(_auxv)\n"     /* load _auxv into a3 (lo)                       */
+		"sw $t0, ($a3)\n"             /* store t0 into _auxv                           */
 
 		"li $t0, -8\n"
-		"and $sp, $sp, $t0\n"   // sp must be 8-byte aligned
-		"addiu $sp,$sp,-16\n"   // the callee expects to save a0..a3 there!
-		"jal main\n"            // main() returns the status code, we'll exit with it.
-		"nop\n"                 // delayed slot
-		"move $a0, $v0\n"       // retrieve 32-bit exit code from v0
-		"li $v0, 4001\n"        // NR_exit == 4001
+		"and $sp, $sp, $t0\n"   /* sp must be 8-byte aligned                           */
+		"addiu $sp,$sp,-16\n"   /* the callee expects to save a0..a3 there!            */
+		"jal main\n"            /* main() returns the status code, we'll exit with it. */
+		"nop\n"                 /* delayed slot                                        */
+		"move $a0, $v0\n"       /* retrieve 32-bit exit code from v0                   */
+		"li $v0, 4001\n"        /* NR_exit == 4001                                     */
 		"syscall\n"
-		//".end __start\n"
+		/*".end __start\n"*/
 		".set pop\n"
 	);
 	__builtin_unreachable();
 }
 
-#endif // _NOLIBC_ARCH_MIPS_H
+#endif /* _NOLIBC_ARCH_MIPS_H */
diff --git a/tools/include/nolibc/arch-riscv.h b/tools/include/nolibc/arch-riscv.h
index e197fcb10ac002..a2e8564e66d6a8 100644
--- a/tools/include/nolibc/arch-riscv.h
+++ b/tools/include/nolibc/arch-riscv.h
@@ -7,6 +7,8 @@
 #ifndef _NOLIBC_ARCH_RISCV_H
 #define _NOLIBC_ARCH_RISCV_H
 
+#include "compiler.h"
+
 struct sys_stat_struct {
 	unsigned long	st_dev;		/* Device.  */
 	unsigned long	st_ino;		/* File serial number.  */
@@ -33,9 +35,13 @@ struct sys_stat_struct {
 #if   __riscv_xlen == 64
 #define PTRLOG "3"
 #define SZREG  "8"
+#define REG_L  "ld"
+#define REG_S  "sd"
 #elif __riscv_xlen == 32
 #define PTRLOG "2"
 #define SZREG  "4"
+#define REG_L  "lw"
+#define REG_S  "sw"
 #endif
 
 /* Syscalls for RISCV :
@@ -174,35 +180,38 @@ char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
 /* startup code */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
 {
 	__asm__ volatile (
 		".option push\n"
 		".option norelax\n"
 		"lla   gp, __global_pointer$\n"
 		".option pop\n"
-		"lw    a0, 0(sp)\n"          // argc (a0) was in the stack
-		"add   a1, sp, "SZREG"\n"    // argv (a1) = sp
-		"slli  a2, a0, "PTRLOG"\n"   // envp (a2) = SZREG*argc ...
-		"add   a2, a2, "SZREG"\n"    //             + SZREG (skip null)
-		"add   a2,a2,a1\n"           //             + argv
-
-		"add   a3, a2, zero\n"       // iterate a3 over envp to find auxv (after NULL)
-		"0:\n"                       // do {
-		"ld    a4, 0(a3)\n"          //   a4 = *a3;
-		"add   a3, a3, "SZREG"\n"    //   a3 += sizeof(void*);
-		"bne   a4, zero, 0b\n"       // } while (a4);
-		"lui   a4, %hi(_auxv)\n"     // a4 = &_auxv (high bits)
-		"sd    a3, %lo(_auxv)(a4)\n" // store a3 into _auxv
-
-		"lui a3, %hi(environ)\n"     // a3 = &environ (high bits)
-		"sd a2,%lo(environ)(a3)\n"   // store envp(a2) into environ
-		"andi  sp,a1,-16\n"          // sp must be 16-byte aligned
-		"call  main\n"               // main() returns the status code, we'll exit with it.
-		"li a7, 93\n"                // NR_exit == 93
+#ifdef _NOLIBC_STACKPROTECTOR
+		"call __stack_chk_init\n"    /* initialize stack protector                          */
+#endif
+		REG_L" a0, 0(sp)\n"          /* argc (a0) was in the stack                          */
+		"add   a1, sp, "SZREG"\n"    /* argv (a1) = sp                                      */
+		"slli  a2, a0, "PTRLOG"\n"   /* envp (a2) = SZREG*argc ...                          */
+		"add   a2, a2, "SZREG"\n"    /*             + SZREG (skip null)                     */
+		"add   a2,a2,a1\n"           /*             + argv                                  */
+
+		"add   a3, a2, zero\n"       /* iterate a3 over envp to find auxv (after NULL)      */
+		"0:\n"                       /* do {                                                */
+		REG_L" a4, 0(a3)\n"          /*   a4 = *a3;                                         */
+		"add   a3, a3, "SZREG"\n"    /*   a3 += sizeof(void*);                              */
+		"bne   a4, zero, 0b\n"       /* } while (a4);                                       */
+		"lui   a4, %hi(_auxv)\n"     /* a4 = &_auxv (high bits)                             */
+		REG_S" a3, %lo(_auxv)(a4)\n" /* store a3 into _auxv                                 */
+
+		"lui   a3, %hi(environ)\n"   /* a3 = &environ (high bits)                           */
+		REG_S" a2,%lo(environ)(a3)\n"/* store envp(a2) into environ                         */
+		"andi  sp,a1,-16\n"          /* sp must be 16-byte aligned                          */
+		"call  main\n"               /* main() returns the status code, we'll exit with it. */
+		"li a7, 93\n"                /* NR_exit == 93                                       */
 		"ecall\n"
 	);
 	__builtin_unreachable();
 }
 
-#endif // _NOLIBC_ARCH_RISCV_H
+#endif /* _NOLIBC_ARCH_RISCV_H */
diff --git a/tools/include/nolibc/arch-s390.h b/tools/include/nolibc/arch-s390.h
index 6b0e54ed543dd8..516dff5bff8bce 100644
--- a/tools/include/nolibc/arch-s390.h
+++ b/tools/include/nolibc/arch-s390.h
@@ -5,8 +5,11 @@
 
 #ifndef _NOLIBC_ARCH_S390_H
 #define _NOLIBC_ARCH_S390_H
+#include <asm/signal.h>
 #include <asm/unistd.h>
 
+#include "compiler.h"
+
 /* The struct returned by the stat() syscall, equivalent to stat64(). The
  * syscall returns 116 bytes and stops in the middle of __unused.
  */
@@ -163,7 +166,7 @@ char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
 /* startup code */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
 {
 	__asm__ volatile (
 		"lg	%r2,0(%r15)\n"		/* argument count */
@@ -223,4 +226,12 @@ void *sys_mmap(void *addr, size_t length, int prot, int flags, int fd,
 	return (void *)my_syscall1(__NR_mmap, &args);
 }
 #define sys_mmap sys_mmap
-#endif // _NOLIBC_ARCH_S390_H
+
+static __attribute__((unused))
+pid_t sys_fork(void)
+{
+	return my_syscall5(__NR_clone, 0, SIGCHLD, 0, 0, 0);
+}
+#define sys_fork sys_fork
+
+#endif /* _NOLIBC_ARCH_S390_H */
diff --git a/tools/include/nolibc/arch-x86_64.h b/tools/include/nolibc/arch-x86_64.h
index f7f2a11d4c3b08..6fc4d83927429d 100644
--- a/tools/include/nolibc/arch-x86_64.h
+++ b/tools/include/nolibc/arch-x86_64.h
@@ -7,6 +7,8 @@
 #ifndef _NOLIBC_ARCH_X86_64_H
 #define _NOLIBC_ARCH_X86_64_H
 
+#include "compiler.h"
+
 /* The struct returned by the stat() syscall, equivalent to stat64(). The
  * syscall returns 116 bytes and stops in the middle of __unused.
  */
@@ -181,8 +183,6 @@ struct sys_stat_struct {
 char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
-#define __ARCH_SUPPORTS_STACK_PROTECTOR
-
 /* startup code */
 /*
  * x86-64 System V ABI mandates:
@@ -190,31 +190,31 @@ const unsigned long *_auxv __attribute__((weak));
  * 2) The deepest stack frame should be zero (the %rbp).
  *
  */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(void)
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void)
 {
 	__asm__ volatile (
-#ifdef NOLIBC_STACKPROTECTOR
-		"call __stack_chk_init\n"   // initialize stack protector
+#ifdef _NOLIBC_STACKPROTECTOR
+		"call __stack_chk_init\n"   /* initialize stack protector                          */
 #endif
-		"pop %rdi\n"                // argc   (first arg, %rdi)
-		"mov %rsp, %rsi\n"          // argv[] (second arg, %rsi)
-		"lea 8(%rsi,%rdi,8),%rdx\n" // then a NULL then envp (third arg, %rdx)
-		"mov %rdx, environ\n"       // save environ
-		"xor %ebp, %ebp\n"          // zero the stack frame
-		"mov %rdx, %rax\n"          // search for auxv (follows NULL after last env)
+		"pop %rdi\n"                /* argc   (first arg, %rdi)                            */
+		"mov %rsp, %rsi\n"          /* argv[] (second arg, %rsi)                           */
+		"lea 8(%rsi,%rdi,8),%rdx\n" /* then a NULL then envp (third arg, %rdx)             */
+		"mov %rdx, environ\n"       /* save environ                                        */
+		"xor %ebp, %ebp\n"          /* zero the stack frame                                */
+		"mov %rdx, %rax\n"          /* search for auxv (follows NULL after last env)       */
 		"0:\n"
-		"add $8, %rax\n"            // search for auxv using rax, it follows the
-		"cmp -8(%rax), %rbp\n"      // ... NULL after last env (rbp is zero here)
+		"add $8, %rax\n"            /* search for auxv using rax, it follows the           */
+		"cmp -8(%rax), %rbp\n"      /* ... NULL after last env (rbp is zero here)          */
 		"jnz 0b\n"
-		"mov %rax, _auxv\n"         // save it into _auxv
-		"and $-16, %rsp\n"          // x86 ABI : esp must be 16-byte aligned before call
-		"call main\n"               // main() returns the status code, we'll exit with it.
-		"mov %eax, %edi\n"          // retrieve exit code (32 bit)
-		"mov $60, %eax\n"           // NR_exit == 60
-		"syscall\n"                 // really exit
-		"hlt\n"                     // ensure it does not return
+		"mov %rax, _auxv\n"         /* save it into _auxv                                  */
+		"and $-16, %rsp\n"          /* x86 ABI : esp must be 16-byte aligned before call   */
+		"call main\n"               /* main() returns the status code, we'll exit with it. */
+		"mov %eax, %edi\n"          /* retrieve exit code (32 bit)                         */
+		"mov $60, %eax\n"           /* NR_exit == 60                                       */
+		"syscall\n"                 /* really exit                                         */
+		"hlt\n"                     /* ensure it does not return                           */
 	);
 	__builtin_unreachable();
 }
 
-#endif // _NOLIBC_ARCH_X86_64_H
+#endif /* _NOLIBC_ARCH_X86_64_H */
diff --git a/tools/include/nolibc/arch.h b/tools/include/nolibc/arch.h
index 2d5386a8d6aacc..82b43935650f4e 100644
--- a/tools/include/nolibc/arch.h
+++ b/tools/include/nolibc/arch.h
@@ -7,7 +7,7 @@
  * the syscall declarations and the _start code definition. This is the only
  * global part. On all architectures the kernel puts everything in the stack
  * before jumping to _start just above us, without any return address (_start
- * is not a function but an entry pint). So at the stack pointer we find argc.
+ * is not a function but an entry point). So at the stack pointer we find argc.
  * Then argv[] begins, and ends at the first NULL. Then we have envp which
  * starts and ends with a NULL as well. So envp=argv+argc+1.
  */
diff --git a/tools/include/nolibc/compiler.h b/tools/include/nolibc/compiler.h
new file mode 100644
index 00000000000000..beddc3665d690e
--- /dev/null
+++ b/tools/include/nolibc/compiler.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * NOLIBC compiler support header
+ * Copyright (C) 2023 Thomas Weißschuh <linux@weissschuh.net>
+ */
+#ifndef _NOLIBC_COMPILER_H
+#define _NOLIBC_COMPILER_H
+
+#if defined(__SSP__) || defined(__SSP_STRONG__) || defined(__SSP_ALL__) || defined(__SSP_EXPLICIT__)
+
+#define _NOLIBC_STACKPROTECTOR
+
+#endif /* defined(__SSP__) ... */
+
+#if defined(__has_attribute)
+#  if __has_attribute(no_stack_protector)
+#    define __no_stack_protector __attribute__((no_stack_protector))
+#  else
+#    define __no_stack_protector __attribute__((__optimize__("-fno-stack-protector")))
+#  endif
+#else
+#  define __no_stack_protector __attribute__((__optimize__("-fno-stack-protector")))
+#endif /* defined(__has_attribute) */
+
+#endif /* _NOLIBC_COMPILER_H */
diff --git a/tools/include/nolibc/nolibc.h b/tools/include/nolibc/nolibc.h
index 04739a6293c488..05a228a6ee782d 100644
--- a/tools/include/nolibc/nolibc.h
+++ b/tools/include/nolibc/nolibc.h
@@ -99,11 +99,11 @@
 #include "sys.h"
 #include "ctype.h"
 #include "signal.h"
+#include "unistd.h"
 #include "stdio.h"
 #include "stdlib.h"
 #include "string.h"
 #include "time.h"
-#include "unistd.h"
 #include "stackprotector.h"
 
 /* Used by programs to avoid std includes */
diff --git a/tools/include/nolibc/stackprotector.h b/tools/include/nolibc/stackprotector.h
index d119cbbbc256f1..88f7b2d098ff70 100644
--- a/tools/include/nolibc/stackprotector.h
+++ b/tools/include/nolibc/stackprotector.h
@@ -7,13 +7,9 @@
 #ifndef _NOLIBC_STACKPROTECTOR_H
 #define _NOLIBC_STACKPROTECTOR_H
 
-#include "arch.h"
+#include "compiler.h"
 
-#if defined(NOLIBC_STACKPROTECTOR)
-
-#if !defined(__ARCH_SUPPORTS_STACK_PROTECTOR)
-#error "nolibc does not support stack protectors on this arch"
-#endif
+#if defined(_NOLIBC_STACKPROTECTOR)
 
 #include "sys.h"
 #include "stdlib.h"
@@ -41,13 +37,14 @@ void __stack_chk_fail_local(void)
 __attribute__((weak,section(".data.nolibc_stack_chk")))
 uintptr_t __stack_chk_guard;
 
-__attribute__((weak,no_stack_protector,section(".text.nolibc_stack_chk")))
+__attribute__((weak,section(".text.nolibc_stack_chk"))) __no_stack_protector
 void __stack_chk_init(void)
 {
 	my_syscall3(__NR_getrandom, &__stack_chk_guard, sizeof(__stack_chk_guard), 0);
-	/* a bit more randomness in case getrandom() fails */
-	__stack_chk_guard ^= (uintptr_t) &__stack_chk_guard;
+	/* a bit more randomness in case getrandom() fails, ensure the guard is never 0 */
+	if (__stack_chk_guard != (uintptr_t) &__stack_chk_guard)
+		__stack_chk_guard ^= (uintptr_t) &__stack_chk_guard;
 }
-#endif // defined(NOLIBC_STACKPROTECTOR)
+#endif /* defined(_NOLIBC_STACKPROTECTOR) */
 
-#endif // _NOLIBC_STACKPROTECTOR_H
+#endif /* _NOLIBC_STACKPROTECTOR_H */
diff --git a/tools/include/nolibc/stdint.h b/tools/include/nolibc/stdint.h
index c1ce4f5e060341..4b282435a59a63 100644
--- a/tools/include/nolibc/stdint.h
+++ b/tools/include/nolibc/stdint.h
@@ -36,8 +36,8 @@ typedef  ssize_t       int_fast16_t;
 typedef   size_t      uint_fast16_t;
 typedef  ssize_t       int_fast32_t;
 typedef   size_t      uint_fast32_t;
-typedef  ssize_t       int_fast64_t;
-typedef   size_t      uint_fast64_t;
+typedef  int64_t       int_fast64_t;
+typedef uint64_t      uint_fast64_t;
 
 typedef  int64_t           intmax_t;
 typedef uint64_t          uintmax_t;
@@ -84,16 +84,30 @@ typedef uint64_t          uintmax_t;
 #define  INT_FAST8_MIN   INT8_MIN
 #define INT_FAST16_MIN   INTPTR_MIN
 #define INT_FAST32_MIN   INTPTR_MIN
-#define INT_FAST64_MIN   INTPTR_MIN
+#define INT_FAST64_MIN   INT64_MIN
 
 #define  INT_FAST8_MAX   INT8_MAX
 #define INT_FAST16_MAX   INTPTR_MAX
 #define INT_FAST32_MAX   INTPTR_MAX
-#define INT_FAST64_MAX   INTPTR_MAX
+#define INT_FAST64_MAX   INT64_MAX
 
 #define  UINT_FAST8_MAX  UINT8_MAX
 #define UINT_FAST16_MAX  SIZE_MAX
 #define UINT_FAST32_MAX  SIZE_MAX
-#define UINT_FAST64_MAX  SIZE_MAX
+#define UINT_FAST64_MAX  UINT64_MAX
+
+#ifndef INT_MIN
+#define INT_MIN          (-__INT_MAX__ - 1)
+#endif
+#ifndef INT_MAX
+#define INT_MAX          __INT_MAX__
+#endif
+
+#ifndef LONG_MIN
+#define LONG_MIN         (-__LONG_MAX__ - 1)
+#endif
+#ifndef LONG_MAX
+#define LONG_MAX         __LONG_MAX__
+#endif
 
 #endif /* _NOLIBC_STDINT_H */
diff --git a/tools/include/nolibc/stdio.h b/tools/include/nolibc/stdio.h
index 6cbbb52836a00f..0eef91daf2898b 100644
--- a/tools/include/nolibc/stdio.h
+++ b/tools/include/nolibc/stdio.h
@@ -21,17 +21,75 @@
 #define EOF (-1)
 #endif
 
-/* just define FILE as a non-empty type */
+/* just define FILE as a non-empty type. The value of the pointer gives
+ * the FD: FILE=~fd for fd>=0 or NULL for fd<0. This way positive FILE
+ * are immediately identified as abnormal entries (i.e. possible copies
+ * of valid pointers to something else).
+ */
 typedef struct FILE {
 	char dummy[1];
 } FILE;
 
-/* We define the 3 common stdio files as constant invalid pointers that
- * are easily recognized.
- */
-static __attribute__((unused)) FILE* const stdin  = (FILE*)-3;
-static __attribute__((unused)) FILE* const stdout = (FILE*)-2;
-static __attribute__((unused)) FILE* const stderr = (FILE*)-1;
+static __attribute__((unused)) FILE* const stdin  = (FILE*)(intptr_t)~STDIN_FILENO;
+static __attribute__((unused)) FILE* const stdout = (FILE*)(intptr_t)~STDOUT_FILENO;
+static __attribute__((unused)) FILE* const stderr = (FILE*)(intptr_t)~STDERR_FILENO;
+
+/* provides a FILE* equivalent of fd. The mode is ignored. */
+static __attribute__((unused))
+FILE *fdopen(int fd, const char *mode __attribute__((unused)))
+{
+	if (fd < 0) {
+		SET_ERRNO(EBADF);
+		return NULL;
+	}
+	return (FILE*)(intptr_t)~fd;
+}
+
+/* provides the fd of stream. */
+static __attribute__((unused))
+int fileno(FILE *stream)
+{
+	intptr_t i = (intptr_t)stream;
+
+	if (i >= 0) {
+		SET_ERRNO(EBADF);
+		return -1;
+	}
+	return ~i;
+}
+
+/* flush a stream. */
+static __attribute__((unused))
+int fflush(FILE *stream)
+{
+	intptr_t i = (intptr_t)stream;
+
+	/* NULL is valid here. */
+	if (i > 0) {
+		SET_ERRNO(EBADF);
+		return -1;
+	}
+
+	/* Don't do anything, nolibc does not support buffering. */
+	return 0;
+}
+
+/* flush a stream. */
+static __attribute__((unused))
+int fclose(FILE *stream)
+{
+	intptr_t i = (intptr_t)stream;
+
+	if (i >= 0) {
+		SET_ERRNO(EBADF);
+		return -1;
+	}
+
+	if (close(~i))
+		return EOF;
+
+	return 0;
+}
 
 /* getc(), fgetc(), getchar() */
 
@@ -41,14 +99,8 @@ static __attribute__((unused))
 int fgetc(FILE* stream)
 {
 	unsigned char ch;
-	int fd;
 
-	if (stream < stdin || stream > stderr)
-		return EOF;
-
-	fd = 3 + (long)stream;
-
-	if (read(fd, &ch, 1) <= 0)
+	if (read(fileno(stream), &ch, 1) <= 0)
 		return EOF;
 	return ch;
 }
@@ -68,14 +120,8 @@ static __attribute__((unused))
 int fputc(int c, FILE* stream)
 {
 	unsigned char ch = c;
-	int fd;
-
-	if (stream < stdin || stream > stderr)
-		return EOF;
-
-	fd = 3 + (long)stream;
 
-	if (write(fd, &ch, 1) <= 0)
+	if (write(fileno(stream), &ch, 1) <= 0)
 		return EOF;
 	return ch;
 }
@@ -96,12 +142,7 @@ static __attribute__((unused))
 int _fwrite(const void *buf, size_t size, FILE *stream)
 {
 	ssize_t ret;
-	int fd;
-
-	if (stream < stdin || stream > stderr)
-		return EOF;
-
-	fd = 3 + (long)stream;
+	int fd = fileno(stream);
 
 	while (size) {
 		ret = write(fd, buf, size);
diff --git a/tools/include/nolibc/stdlib.h b/tools/include/nolibc/stdlib.h
index 894c955d027e48..902162f80337d7 100644
--- a/tools/include/nolibc/stdlib.h
+++ b/tools/include/nolibc/stdlib.h
@@ -102,7 +102,7 @@ char *_getenv(const char *name, char **environ)
 	return NULL;
 }
 
-static inline __attribute__((unused,always_inline))
+static __inline__ __attribute__((unused,always_inline))
 char *getenv(const char *name)
 {
 	extern char **environ;
@@ -231,7 +231,7 @@ int utoh_r(unsigned long in, char *buffer)
 /* converts unsigned long <in> to an hex string using the static itoa_buffer
  * and returns the pointer to that string.
  */
-static inline __attribute__((unused))
+static __inline__ __attribute__((unused))
 char *utoh(unsigned long in)
 {
 	utoh_r(in, itoa_buffer);
@@ -293,7 +293,7 @@ int itoa_r(long in, char *buffer)
 /* for historical compatibility, same as above but returns the pointer to the
  * buffer.
  */
-static inline __attribute__((unused))
+static __inline__ __attribute__((unused))
 char *ltoa_r(long in, char *buffer)
 {
 	itoa_r(in, buffer);
@@ -303,7 +303,7 @@ char *ltoa_r(long in, char *buffer)
 /* converts long integer <in> to a string using the static itoa_buffer and
  * returns the pointer to that string.
  */
-static inline __attribute__((unused))
+static __inline__ __attribute__((unused))
 char *itoa(long in)
 {
 	itoa_r(in, itoa_buffer);
@@ -313,7 +313,7 @@ char *itoa(long in)
 /* converts long integer <in> to a string using the static itoa_buffer and
  * returns the pointer to that string. Same as above, for compatibility.
  */
-static inline __attribute__((unused))
+static __inline__ __attribute__((unused))
 char *ltoa(long in)
 {
 	itoa_r(in, itoa_buffer);
@@ -323,7 +323,7 @@ char *ltoa(long in)
 /* converts unsigned long integer <in> to a string using the static itoa_buffer
  * and returns the pointer to that string.
  */
-static inline __attribute__((unused))
+static __inline__ __attribute__((unused))
 char *utoa(unsigned long in)
 {
 	utoa_r(in, itoa_buffer);
@@ -367,7 +367,7 @@ int u64toh_r(uint64_t in, char *buffer)
 /* converts uint64_t <in> to an hex string using the static itoa_buffer and
  * returns the pointer to that string.
  */
-static inline __attribute__((unused))
+static __inline__ __attribute__((unused))
 char *u64toh(uint64_t in)
 {
 	u64toh_r(in, itoa_buffer);
@@ -429,7 +429,7 @@ int i64toa_r(int64_t in, char *buffer)
 /* converts int64_t <in> to a string using the static itoa_buffer and returns
  * the pointer to that string.
  */
-static inline __attribute__((unused))
+static __inline__ __attribute__((unused))
 char *i64toa(int64_t in)
 {
 	i64toa_r(in, itoa_buffer);
@@ -439,7 +439,7 @@ char *i64toa(int64_t in)
 /* converts uint64_t <in> to a string using the static itoa_buffer and returns
  * the pointer to that string.
  */
-static inline __attribute__((unused))
+static __inline__ __attribute__((unused))
 char *u64toa(uint64_t in)
 {
 	u64toa_r(in, itoa_buffer);
diff --git a/tools/include/nolibc/string.h b/tools/include/nolibc/string.h
index fffdaf6ff46731..0c2e06c7c4772b 100644
--- a/tools/include/nolibc/string.h
+++ b/tools/include/nolibc/string.h
@@ -90,7 +90,7 @@ void *memset(void *dst, int b, size_t len)
 
 	while (len--) {
 		/* prevent gcc from recognizing memset() here */
-		asm volatile("");
+		__asm__ volatile("");
 		*(p++) = b;
 	}
 	return dst;
@@ -139,7 +139,7 @@ size_t strlen(const char *str)
 	size_t len;
 
 	for (len = 0; str[len]; len++)
-		asm("");
+		__asm__("");
 	return len;
 }
 
diff --git a/tools/include/nolibc/sys.h b/tools/include/nolibc/sys.h
index 5d624dc63a424c..856249a118901c 100644
--- a/tools/include/nolibc/sys.h
+++ b/tools/include/nolibc/sys.h
@@ -12,15 +12,17 @@
 
 /* system includes */
 #include <asm/unistd.h>
-#include <asm/signal.h>  // for SIGCHLD
+#include <asm/signal.h>  /* for SIGCHLD */
 #include <asm/ioctls.h>
 #include <asm/mman.h>
 #include <linux/fs.h>
 #include <linux/loop.h>
 #include <linux/time.h>
 #include <linux/auxvec.h>
-#include <linux/fcntl.h> // for O_* and AT_*
-#include <linux/stat.h>  // for statx()
+#include <linux/fcntl.h> /* for O_* and AT_* */
+#include <linux/stat.h>  /* for statx() */
+#include <linux/reboot.h> /* for LINUX_REBOOT_* */
+#include <linux/prctl.h>
 
 #include "arch.h"
 #include "errno.h"
@@ -322,7 +324,7 @@ static __attribute__((noreturn,unused))
 void sys_exit(int status)
 {
 	my_syscall1(__NR_exit, status & 255);
-	while(1); // shut the "noreturn" warnings.
+	while(1); /* shut the "noreturn" warnings. */
 }
 
 static __attribute__((noreturn,unused))
@@ -336,6 +338,7 @@ void exit(int status)
  * pid_t fork(void);
  */
 
+#ifndef sys_fork
 static __attribute__((unused))
 pid_t sys_fork(void)
 {
@@ -351,6 +354,7 @@ pid_t sys_fork(void)
 #error Neither __NR_clone nor __NR_fork defined, cannot implement sys_fork()
 #endif
 }
+#endif
 
 static __attribute__((unused))
 pid_t fork(void)
@@ -858,7 +862,7 @@ int open(const char *path, int flags, ...)
 		va_list args;
 
 		va_start(args, flags);
-		mode = va_arg(args, mode_t);
+		mode = va_arg(args, int);
 		va_end(args);
 	}
 
@@ -873,6 +877,32 @@ int open(const char *path, int flags, ...)
 
 
 /*
+ * int prctl(int option, unsigned long arg2, unsigned long arg3,
+ *                       unsigned long arg4, unsigned long arg5);
+ */
+
+static __attribute__((unused))
+int sys_prctl(int option, unsigned long arg2, unsigned long arg3,
+		          unsigned long arg4, unsigned long arg5)
+{
+	return my_syscall5(__NR_prctl, option, arg2, arg3, arg4, arg5);
+}
+
+static __attribute__((unused))
+int prctl(int option, unsigned long arg2, unsigned long arg3,
+		      unsigned long arg4, unsigned long arg5)
+{
+	int ret = sys_prctl(option, arg2, arg3, arg4, arg5);
+
+	if (ret < 0) {
+		SET_ERRNO(-ret);
+		ret = -1;
+	}
+	return ret;
+}
+
+
+/*
  * int pivot_root(const char *new, const char *old);
  */
 
@@ -909,7 +939,7 @@ int sys_poll(struct pollfd *fds, int nfds, int timeout)
 		t.tv_sec  = timeout / 1000;
 		t.tv_nsec = (timeout % 1000) * 1000000;
 	}
-	return my_syscall4(__NR_ppoll, fds, nfds, (timeout >= 0) ? &t : NULL, NULL);
+	return my_syscall5(__NR_ppoll, fds, nfds, (timeout >= 0) ? &t : NULL, NULL, 0);
 #elif defined(__NR_poll)
 	return my_syscall3(__NR_poll, fds, nfds, timeout);
 #else
@@ -1131,23 +1161,26 @@ int sys_stat(const char *path, struct stat *buf)
 	long ret;
 
 	ret = sys_statx(AT_FDCWD, path, AT_NO_AUTOMOUNT, STATX_BASIC_STATS, &statx);
-	buf->st_dev     = ((statx.stx_dev_minor & 0xff)
-			  | (statx.stx_dev_major << 8)
-			  | ((statx.stx_dev_minor & ~0xff) << 12));
-	buf->st_ino     = statx.stx_ino;
-	buf->st_mode    = statx.stx_mode;
-	buf->st_nlink   = statx.stx_nlink;
-	buf->st_uid     = statx.stx_uid;
-	buf->st_gid     = statx.stx_gid;
-	buf->st_rdev    = ((statx.stx_rdev_minor & 0xff)
-			  | (statx.stx_rdev_major << 8)
-			  | ((statx.stx_rdev_minor & ~0xff) << 12));
-	buf->st_size    = statx.stx_size;
-	buf->st_blksize = statx.stx_blksize;
-	buf->st_blocks  = statx.stx_blocks;
-	buf->st_atime   = statx.stx_atime.tv_sec;
-	buf->st_mtime   = statx.stx_mtime.tv_sec;
-	buf->st_ctime   = statx.stx_ctime.tv_sec;
+	buf->st_dev          = ((statx.stx_dev_minor & 0xff)
+			       | (statx.stx_dev_major << 8)
+			       | ((statx.stx_dev_minor & ~0xff) << 12));
+	buf->st_ino          = statx.stx_ino;
+	buf->st_mode         = statx.stx_mode;
+	buf->st_nlink        = statx.stx_nlink;
+	buf->st_uid          = statx.stx_uid;
+	buf->st_gid          = statx.stx_gid;
+	buf->st_rdev         = ((statx.stx_rdev_minor & 0xff)
+			       | (statx.stx_rdev_major << 8)
+			       | ((statx.stx_rdev_minor & ~0xff) << 12));
+	buf->st_size         = statx.stx_size;
+	buf->st_blksize      = statx.stx_blksize;
+	buf->st_blocks       = statx.stx_blocks;
+	buf->st_atim.tv_sec  = statx.stx_atime.tv_sec;
+	buf->st_atim.tv_nsec = statx.stx_atime.tv_nsec;
+	buf->st_mtim.tv_sec  = statx.stx_mtime.tv_sec;
+	buf->st_mtim.tv_nsec = statx.stx_mtime.tv_nsec;
+	buf->st_ctim.tv_sec  = statx.stx_ctime.tv_sec;
+	buf->st_ctim.tv_nsec = statx.stx_ctime.tv_nsec;
 	return ret;
 }
 #else
@@ -1165,19 +1198,22 @@ int sys_stat(const char *path, struct stat *buf)
 #else
 #error Neither __NR_newfstatat nor __NR_stat defined, cannot implement sys_stat()
 #endif
-	buf->st_dev     = stat.st_dev;
-	buf->st_ino     = stat.st_ino;
-	buf->st_mode    = stat.st_mode;
-	buf->st_nlink   = stat.st_nlink;
-	buf->st_uid     = stat.st_uid;
-	buf->st_gid     = stat.st_gid;
-	buf->st_rdev    = stat.st_rdev;
-	buf->st_size    = stat.st_size;
-	buf->st_blksize = stat.st_blksize;
-	buf->st_blocks  = stat.st_blocks;
-	buf->st_atime   = stat.st_atime;
-	buf->st_mtime   = stat.st_mtime;
-	buf->st_ctime   = stat.st_ctime;
+	buf->st_dev          = stat.st_dev;
+	buf->st_ino          = stat.st_ino;
+	buf->st_mode         = stat.st_mode;
+	buf->st_nlink        = stat.st_nlink;
+	buf->st_uid          = stat.st_uid;
+	buf->st_gid          = stat.st_gid;
+	buf->st_rdev         = stat.st_rdev;
+	buf->st_size         = stat.st_size;
+	buf->st_blksize      = stat.st_blksize;
+	buf->st_blocks       = stat.st_blocks;
+	buf->st_atim.tv_sec  = stat.st_atime;
+	buf->st_atim.tv_nsec = stat.st_atime_nsec;
+	buf->st_mtim.tv_sec  = stat.st_mtime;
+	buf->st_mtim.tv_nsec = stat.st_mtime_nsec;
+	buf->st_ctim.tv_sec  = stat.st_ctime;
+	buf->st_ctim.tv_nsec = stat.st_ctime_nsec;
 	return ret;
 }
 #endif
@@ -1365,6 +1401,29 @@ ssize_t write(int fd, const void *buf, size_t count)
 	return ret;
 }
 
+
+/*
+ * int memfd_create(const char *name, unsigned int flags);
+ */
+
+static __attribute__((unused))
+int sys_memfd_create(const char *name, unsigned int flags)
+{
+	return my_syscall2(__NR_memfd_create, name, flags);
+}
+
+static __attribute__((unused))
+int memfd_create(const char *name, unsigned int flags)
+{
+	ssize_t ret = sys_memfd_create(name, flags);
+
+	if (ret < 0) {
+		SET_ERRNO(-ret);
+		ret = -1;
+	}
+	return ret;
+}
+
 /* make sure to include all global symbols */
 #include "nolibc.h"
 
diff --git a/tools/include/nolibc/types.h b/tools/include/nolibc/types.h
index aedd7d9e3f6440..f96e28bff4bacc 100644
--- a/tools/include/nolibc/types.h
+++ b/tools/include/nolibc/types.h
@@ -86,14 +86,6 @@
 #define SEEK_CUR       1
 #define SEEK_END       2
 
-/* cmd for reboot() */
-#define LINUX_REBOOT_MAGIC1         0xfee1dead
-#define LINUX_REBOOT_MAGIC2         0x28121969
-#define LINUX_REBOOT_CMD_HALT       0xcdef0123
-#define LINUX_REBOOT_CMD_POWER_OFF  0x4321fedc
-#define LINUX_REBOOT_CMD_RESTART    0x01234567
-#define LINUX_REBOOT_CMD_SW_SUSPEND 0xd000fce2
-
 /* Macros used on waitpid()'s return status */
 #define WEXITSTATUS(status) (((status) & 0xff00) >> 8)
 #define WIFEXITED(status)   (((status) & 0x7f) == 0)
@@ -206,9 +198,9 @@ struct stat {
 	off_t     st_size;    /* total size, in bytes */
 	blksize_t st_blksize; /* blocksize for file system I/O */
 	blkcnt_t  st_blocks;  /* number of 512B blocks allocated */
-	time_t    st_atime;   /* time of last access */
-	time_t    st_mtime;   /* time of last modification */
-	time_t    st_ctime;   /* time of last status change */
+	union { time_t st_atime; struct timespec st_atim; }; /* time of last access */
+	union { time_t st_mtime; struct timespec st_mtim; }; /* time of last modification */
+	union { time_t st_ctime; struct timespec st_ctim; }; /* time of last status change */
 };
 
 /* WARNING, it only deals with the 4096 first majors and 256 first minors */
diff --git a/tools/include/nolibc/unistd.h b/tools/include/nolibc/unistd.h
index ac7d53d986cd11..0e832e10a0b278 100644
--- a/tools/include/nolibc/unistd.h
+++ b/tools/include/nolibc/unistd.h
@@ -56,6 +56,21 @@ int tcsetpgrp(int fd, pid_t pid)
 	return ioctl(fd, TIOCSPGRP, &pid);
 }
 
+#define _syscall(N, ...)                                                      \
+({                                                                            \
+	long _ret = my_syscall##N(__VA_ARGS__);                               \
+	if (_ret < 0) {                                                       \
+		SET_ERRNO(-_ret);                                             \
+		_ret = -1;                                                    \
+	}                                                                     \
+	_ret;                                                                 \
+})
+
+#define _syscall_narg(...) __syscall_narg(__VA_ARGS__, 6, 5, 4, 3, 2, 1, 0)
+#define __syscall_narg(_0, _1, _2, _3, _4, _5, _6, N, ...) N
+#define _syscall_n(N, ...) _syscall(N, __VA_ARGS__)
+#define syscall(...) _syscall_n(_syscall_narg(__VA_ARGS__), ##__VA_ARGS__)
+
 /* make sure to include all global symbols */
 #include "nolibc.h"
 
diff --git a/tools/testing/selftests/nolibc/.gitignore b/tools/testing/selftests/nolibc/.gitignore
index 4696df589d68e5..52f613cdad5477 100644
--- a/tools/testing/selftests/nolibc/.gitignore
+++ b/tools/testing/selftests/nolibc/.gitignore
@@ -1,4 +1,5 @@
 /initramfs/
+/libc-test
 /nolibc-test
 /run.out
 /sysroot/
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index bbce57420465cd..1b7b3c82f8add3 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -64,7 +64,7 @@ QEMU_ARGS_mips       = -M malta -append "panic=-1 $(TEST:%=NOLIBC_TEST=%)"
 QEMU_ARGS_riscv      = -M virt -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
 QEMU_ARGS_s390       = -M s390-ccw-virtio -m 1G -append "console=ttyS0 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
 QEMU_ARGS_loongarch  = -M virt -append "console=ttyS0,115200 panic=-1 $(TEST:%=NOLIBC_TEST=%)"
-QEMU_ARGS            = $(QEMU_ARGS_$(ARCH))
+QEMU_ARGS            = $(QEMU_ARGS_$(ARCH)) $(QEMU_ARGS_EXTRA)
 
 # OUTPUT is only set when run from the main makefile, otherwise
 # it defaults to this nolibc directory.
@@ -76,16 +76,12 @@ else
 Q=@
 endif
 
-CFLAGS_STACKPROTECTOR = -DNOLIBC_STACKPROTECTOR \
-			$(call cc-option,-mstack-protector-guard=global) \
-			$(call cc-option,-fstack-protector-all)
-CFLAGS_STKP_i386 = $(CFLAGS_STACKPROTECTOR)
-CFLAGS_STKP_x86_64 = $(CFLAGS_STACKPROTECTOR)
-CFLAGS_STKP_x86 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_s390 = -m64
-CFLAGS  ?= -Os -fno-ident -fno-asynchronous-unwind-tables \
+CFLAGS_mips = -EL
+CFLAGS_STACKPROTECTOR ?= $(call cc-option,-mstack-protector-guard=global $(call cc-option,-fstack-protector-all))
+CFLAGS  ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 \
 		$(call cc-option,-fno-stack-protector) \
-		$(CFLAGS_STKP_$(ARCH)) $(CFLAGS_$(ARCH))
+		$(CFLAGS_$(ARCH)) $(CFLAGS_STACKPROTECTOR)
 LDFLAGS := -s
 
 help:
@@ -94,6 +90,7 @@ help:
 	@echo "  help         this help"
 	@echo "  sysroot      create the nolibc sysroot here (uses \$$ARCH)"
 	@echo "  nolibc-test  build the executable (uses \$$CC and \$$CROSS_COMPILE)"
+	@echo "  libc-test    build an executable using the compiler's default libc instead"
 	@echo "  run-user     runs the executable under QEMU (uses \$$ARCH, \$$TEST)"
 	@echo "  initramfs    prepare the initramfs with nolibc-test"
 	@echo "  defconfig    create a fresh new default config (uses \$$ARCH)"
@@ -128,10 +125,16 @@ nolibc-test: nolibc-test.c sysroot/$(ARCH)/include
 	$(QUIET_CC)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ \
 	  -nostdlib -static -Isysroot/$(ARCH)/include $< -lgcc
 
+libc-test: nolibc-test.c
+	$(QUIET_CC)$(CC) -o $@ $<
+
 # qemu user-land test
 run-user: nolibc-test
 	$(Q)qemu-$(QEMU_ARCH) ./nolibc-test > "$(CURDIR)/run.out" || :
-	$(Q)grep -w FAIL "$(CURDIR)/run.out" && echo "See all results in $(CURDIR)/run.out" || echo "$$(grep -c ^[0-9].*OK $(CURDIR)/run.out) test(s) passed."
+	$(Q)awk '/\[OK\][\r]*$$/{p++} /\[FAIL\][\r]*$$/{f++} /\[SKIPPED\][\r]*$$/{s++} \
+	         END{ printf("%d test(s) passed, %d skipped, %d failed.", p, s, f); \
+	         if (s+f > 0) printf(" See all results in %s\n", ARGV[1]); else print; }' \
+	         $(CURDIR)/run.out
 
 initramfs: nolibc-test
 	$(QUIET_MKDIR)mkdir -p initramfs
@@ -147,18 +150,26 @@ kernel: initramfs
 # run the tests after building the kernel
 run: kernel
 	$(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(srctree)/$(IMAGE)" -serial stdio $(QEMU_ARGS) > "$(CURDIR)/run.out"
-	$(Q)grep -w FAIL "$(CURDIR)/run.out" && echo "See all results in $(CURDIR)/run.out" || echo "$$(grep -c ^[0-9].*OK $(CURDIR)/run.out) test(s) passed."
+	$(Q)awk '/\[OK\][\r]*$$/{p++} /\[FAIL\][\r]*$$/{f++} /\[SKIPPED\][\r]*$$/{s++} \
+	         END{ printf("%d test(s) passed, %d skipped, %d failed.", p, s, f); \
+	         if (s+f > 0) printf(" See all results in %s\n", ARGV[1]); else print; }' \
+	         $(CURDIR)/run.out
 
 # re-run the tests from an existing kernel
 rerun:
 	$(Q)qemu-system-$(QEMU_ARCH) -display none -no-reboot -kernel "$(srctree)/$(IMAGE)" -serial stdio $(QEMU_ARGS) > "$(CURDIR)/run.out"
-	$(Q)grep -w FAIL "$(CURDIR)/run.out" && echo "See all results in $(CURDIR)/run.out" || echo "$$(grep -c ^[0-9].*OK $(CURDIR)/run.out) test(s) passed."
+	$(Q)awk '/\[OK\][\r]*$$/{p++} /\[FAIL\][\r]*$$/{f++} /\[SKIPPED\][\r]*$$/{s++} \
+	         END{ printf("%d test(s) passed, %d skipped, %d failed.", p, s, f); \
+	         if (s+f > 0) printf(" See all results in %s\n", ARGV[1]); else print; }' \
+	         $(CURDIR)/run.out
 
 clean:
 	$(call QUIET_CLEAN, sysroot)
 	$(Q)rm -rf sysroot
 	$(call QUIET_CLEAN, nolibc-test)
 	$(Q)rm -f nolibc-test
+	$(call QUIET_CLEAN, libc-test)
+	$(Q)rm -f libc-test
 	$(call QUIET_CLEAN, initramfs)
 	$(Q)rm -rf initramfs
 	$(call QUIET_CLEAN, run.out)
diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index 21bacc928bf7b2..486334981e6015 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -1,10 +1,7 @@
-// SPDX-License-Identifier: GPL-2.0
+/* SPDX-License-Identifier: GPL-2.0 */
 
 #define _GNU_SOURCE
 
-/* platform-specific include files coming from the compiler */
-#include <limits.h>
-
 /* libc-specific include files
  * The program may be built in 3 ways:
  *   $(CC) -nostdlib -include /path/to/nolibc.h => NOLIBC already defined
@@ -20,7 +17,9 @@
 #include <linux/reboot.h>
 #include <sys/io.h>
 #include <sys/ioctl.h>
+#include <sys/mman.h>
 #include <sys/mount.h>
+#include <sys/prctl.h>
 #include <sys/reboot.h>
 #include <sys/stat.h>
 #include <sys/syscall.h>
@@ -34,7 +33,10 @@
 #include <sched.h>
 #include <signal.h>
 #include <stdarg.h>
+#include <stddef.h>
+#include <stdint.h>
 #include <unistd.h>
+#include <limits.h>
 #endif
 #endif
 
@@ -43,8 +45,8 @@ char **environ;
 
 /* definition of a series of tests */
 struct test {
-	const char *name;              // test name
-	int (*func)(int min, int max); // handler
+	const char *name;              /* test name */
+	int (*func)(int min, int max); /* handler */
 };
 
 #ifndef _NOLIBC_STDLIB_H
@@ -103,24 +105,32 @@ const char *errorname(int err)
 	CASE_ERR(EDOM);
 	CASE_ERR(ERANGE);
 	CASE_ERR(ENOSYS);
+	CASE_ERR(EOVERFLOW);
 	default:
 		return itoa(err);
 	}
 }
 
+static void putcharn(char c, size_t n)
+{
+	char buf[64];
+
+	memset(buf, c, n);
+	buf[n] = '\0';
+	fputs(buf, stdout);
+}
+
 static int pad_spc(int llen, int cnt, const char *fmt, ...)
 {
 	va_list args;
-	int len;
 	int ret;
 
-	for (len = 0; len < cnt - llen; len++)
-		putchar(' ');
+	putcharn(' ', cnt - llen);
 
 	va_start(args, fmt);
 	ret = vfprintf(stdout, fmt, args);
 	va_end(args);
-	return ret < 0 ? ret : ret + len;
+	return ret < 0 ? ret : ret + cnt - llen;
 }
 
 /* The tests below are intended to be used by the macroes, which evaluate
@@ -162,7 +172,7 @@ static int expect_eq(uint64_t expr, int llen, uint64_t val)
 {
 	int ret = !(expr == val);
 
-	llen += printf(" = %lld ", expr);
+	llen += printf(" = %lld ", (long long)expr);
 	pad_spc(llen, 64, ret ? "[FAIL]\n" : " [OK]\n");
 	return ret;
 }
@@ -290,18 +300,24 @@ static int expect_sysne(int expr, int llen, int val)
 }
 
 
+#define EXPECT_SYSER2(cond, expr, expret, experr1, experr2)		\
+	do { if (!cond) pad_spc(llen, 64, "[SKIPPED]\n"); else ret += expect_syserr2(expr, expret, experr1, experr2, llen); } while (0)
+
 #define EXPECT_SYSER(cond, expr, expret, experr)			\
-	do { if (!cond) pad_spc(llen, 64, "[SKIPPED]\n"); else ret += expect_syserr(expr, expret, experr, llen); } while (0)
+	EXPECT_SYSER2(cond, expr, expret, experr, 0)
 
-static int expect_syserr(int expr, int expret, int experr, int llen)
+static int expect_syserr2(int expr, int expret, int experr1, int experr2, int llen)
 {
 	int ret = 0;
 	int _errno = errno;
 
 	llen += printf(" = %d %s ", expr, errorname(_errno));
-	if (expr != expret || _errno != experr) {
+	if (expr != expret || (_errno != experr1 && _errno != experr2)) {
 		ret = 1;
-		llen += printf(" != (%d %s) ", expret, errorname(experr));
+		if (experr2 == 0)
+			llen += printf(" != (%d %s) ", expret, errorname(experr1));
+		else
+			llen += printf(" != (%d %s %s) ", expret, errorname(experr1), errorname(experr2));
 		llen += pad_spc(llen, 64, "[FAIL]\n");
 	} else {
 		llen += pad_spc(llen, 64, " [OK]\n");
@@ -471,11 +487,60 @@ static int test_getpagesize(void)
 	return !c;
 }
 
+static int test_fork(void)
+{
+	int status;
+	pid_t pid;
+
+	/* flush the printf buffer to avoid child flush it */
+	fflush(stdout);
+	fflush(stderr);
+
+	pid = fork();
+
+	switch (pid) {
+	case -1:
+		return 1;
+
+	case 0:
+		exit(123);
+
+	default:
+		pid = waitpid(pid, &status, 0);
+
+		return pid == -1 || !WIFEXITED(status) || WEXITSTATUS(status) != 123;
+	}
+}
+
+static int test_stat_timestamps(void)
+{
+	struct stat st;
+
+	if (sizeof(st.st_atim.tv_sec) != sizeof(st.st_atime))
+		return 1;
+
+	if (stat("/proc/self/", &st))
+		return 1;
+
+	if (st.st_atim.tv_sec != st.st_atime || st.st_atim.tv_nsec > 1000000000)
+		return 1;
+
+	if (st.st_mtim.tv_sec != st.st_mtime || st.st_mtim.tv_nsec > 1000000000)
+		return 1;
+
+	if (st.st_ctim.tv_sec != st.st_ctime || st.st_ctim.tv_nsec > 1000000000)
+		return 1;
+
+	return 0;
+}
+
 /* Run syscall tests between IDs <min> and <max>.
  * Return 0 on success, non-zero on failure.
  */
 int run_syscall(int min, int max)
 {
+	struct timeval tv;
+	struct timezone tz;
 	struct stat stat_buf;
 	int euid0;
 	int proc;
@@ -491,7 +556,7 @@ int run_syscall(int min, int max)
 	euid0 = geteuid() == 0;
 
 	for (test = min; test >= 0 && test <= max; test++) {
-		int llen = 0; // line length
+		int llen = 0; /* line length */
 
 		/* avoid leaving empty lines below, this will insert holes into
 		 * test numbers.
@@ -527,14 +592,11 @@ 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(fork);              EXPECT_SYSZR(1, test_fork()); break;
 		CASE_TEST(getdents64_root);   EXPECT_SYSNE(1, test_getdents64("/"), -1); break;
 		CASE_TEST(getdents64_null);   EXPECT_SYSER(1, test_getdents64("/dev/null"), -1, ENOTDIR); break;
-		CASE_TEST(gettimeofday_null); EXPECT_SYSZR(1, gettimeofday(NULL, NULL)); break;
-#ifdef NOLIBC
-		CASE_TEST(gettimeofday_bad1); EXPECT_SYSER(1, gettimeofday((void *)1, NULL), -1, EFAULT); break;
-		CASE_TEST(gettimeofday_bad2); EXPECT_SYSER(1, gettimeofday(NULL, (void *)1), -1, EFAULT); break;
-		CASE_TEST(gettimeofday_bad2); EXPECT_SYSER(1, gettimeofday(NULL, (void *)1), -1, EFAULT); break;
-#endif
+		CASE_TEST(gettimeofday_tv);   EXPECT_SYSZR(1, gettimeofday(&tv, NULL)); break;
+		CASE_TEST(gettimeofday_tv_tz);EXPECT_SYSZR(1, gettimeofday(&tv, &tz)); break;
 		CASE_TEST(getpagesize);       EXPECT_SYSZR(1, test_getpagesize()); break;
 		CASE_TEST(ioctl_tiocinq);     EXPECT_SYSZR(1, ioctl(0, TIOCINQ, &tmp)); break;
 		CASE_TEST(ioctl_tiocinq);     EXPECT_SYSZR(1, ioctl(0, TIOCINQ, &tmp)); break;
@@ -550,6 +612,7 @@ int run_syscall(int min, int max)
 		CASE_TEST(poll_null);         EXPECT_SYSZR(1, poll(NULL, 0, 0)); break;
 		CASE_TEST(poll_stdout);       EXPECT_SYSNE(1, ({ struct pollfd fds = { 1, POLLOUT, 0}; poll(&fds, 1, 0); }), -1); break;
 		CASE_TEST(poll_fault);        EXPECT_SYSER(1, poll((void *)1, 1, 0), -1, EFAULT); break;
+		CASE_TEST(prctl);             EXPECT_SYSER(1, prctl(PR_SET_NAME, (unsigned long)NULL, 0, 0, 0), -1, EFAULT); break;
 		CASE_TEST(read_badf);         EXPECT_SYSER(1, read(-1, &tmp, 1), -1, EBADF); break;
 		CASE_TEST(sched_yield);       EXPECT_SYSZR(1, sched_yield()); break;
 		CASE_TEST(select_null);       EXPECT_SYSZR(1, ({ struct timeval tv = { 0 }; select(0, NULL, NULL, NULL, &tv); })); break;
@@ -557,6 +620,7 @@ int run_syscall(int min, int max)
 		CASE_TEST(select_fault);      EXPECT_SYSER(1, select(1, (void *)1, NULL, NULL, 0), -1, EFAULT); break;
 		CASE_TEST(stat_blah);         EXPECT_SYSER(1, stat("/proc/self/blah", &stat_buf), -1, ENOENT); break;
 		CASE_TEST(stat_fault);        EXPECT_SYSER(1, stat(NULL, &stat_buf), -1, EFAULT); break;
+		CASE_TEST(stat_timestamps);   EXPECT_SYSZR(1, test_stat_timestamps()); break;
 		CASE_TEST(symlink_root);      EXPECT_SYSER(1, symlink("/", "/"), -1, EEXIST); break;
 		CASE_TEST(unlink_root);       EXPECT_SYSER(1, unlink("/"), -1, EISDIR); break;
 		CASE_TEST(unlink_blah);       EXPECT_SYSER(1, unlink("/proc/self/blah"), -1, ENOENT); break;
@@ -565,6 +629,8 @@ 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(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 __LINE__:
 			return ret; /* must be last */
 		/* note: do not set any defaults so as to permit holes above */
@@ -581,7 +647,7 @@ int run_stdlib(int min, int max)
 	void *p1, *p2;
 
 	for (test = min; test >= 0 && test <= max; test++) {
-		int llen = 0; // line length
+		int llen = 0; /* line length */
 
 		/* avoid leaving empty lines below, this will insert holes into
 		 * test numbers.
@@ -639,9 +705,9 @@ int run_stdlib(int min, int max)
 		CASE_TEST(limit_int_fast32_min);    EXPECT_EQ(1, INT_FAST32_MIN,   (int_fast32_t)    INTPTR_MIN); break;
 		CASE_TEST(limit_int_fast32_max);    EXPECT_EQ(1, INT_FAST32_MAX,   (int_fast32_t)    INTPTR_MAX); break;
 		CASE_TEST(limit_uint_fast32_max);   EXPECT_EQ(1, UINT_FAST32_MAX,  (uint_fast32_t)   UINTPTR_MAX); break;
-		CASE_TEST(limit_int_fast64_min);    EXPECT_EQ(1, INT_FAST64_MIN,   (int_fast64_t)    INTPTR_MIN); break;
-		CASE_TEST(limit_int_fast64_max);    EXPECT_EQ(1, INT_FAST64_MAX,   (int_fast64_t)    INTPTR_MAX); break;
-		CASE_TEST(limit_uint_fast64_max);   EXPECT_EQ(1, UINT_FAST64_MAX,  (uint_fast64_t)   UINTPTR_MAX); break;
+		CASE_TEST(limit_int_fast64_min);    EXPECT_EQ(1, INT_FAST64_MIN,   (int_fast64_t)    INT64_MIN); break;
+		CASE_TEST(limit_int_fast64_max);    EXPECT_EQ(1, INT_FAST64_MAX,   (int_fast64_t)    INT64_MAX); break;
+		CASE_TEST(limit_uint_fast64_max);   EXPECT_EQ(1, UINT_FAST64_MAX,  (uint_fast64_t)   UINT64_MAX); break;
 #if __SIZEOF_LONG__ == 8
 		CASE_TEST(limit_intptr_min);        EXPECT_EQ(1, INTPTR_MIN,       (intptr_t)        0x8000000000000000LL); break;
 		CASE_TEST(limit_intptr_max);        EXPECT_EQ(1, INTPTR_MAX,       (intptr_t)        0x7fffffffffffffffLL); break;
@@ -667,17 +733,98 @@ int run_stdlib(int min, int max)
 	return ret;
 }
 
-#if defined(__clang__)
-__attribute__((optnone))
-#elif defined(__GNUC__)
-__attribute__((optimize("O0")))
-#endif
+#define EXPECT_VFPRINTF(c, expected, fmt, ...)				\
+	ret += expect_vfprintf(llen, c, expected, fmt, ##__VA_ARGS__)
+
+static int expect_vfprintf(int llen, size_t c, const char *expected, const char *fmt, ...)
+{
+	int ret, fd, w, r;
+	char buf[100];
+	FILE *memfile;
+	va_list args;
+
+	fd = memfd_create("vfprintf", 0);
+	if (fd == -1) {
+		pad_spc(llen, 64, "[FAIL]\n");
+		return 1;
+	}
+
+	memfile = fdopen(fd, "w+");
+	if (!memfile) {
+		pad_spc(llen, 64, "[FAIL]\n");
+		return 1;
+	}
+
+	va_start(args, fmt);
+	w = vfprintf(memfile, fmt, args);
+	va_end(args);
+
+	if (w != c) {
+		llen += printf(" written(%d) != %d", w, (int) c);
+		pad_spc(llen, 64, "[FAIL]\n");
+		return 1;
+	}
+
+	fflush(memfile);
+	lseek(fd, 0, SEEK_SET);
+
+	r = read(fd, buf, sizeof(buf) - 1);
+	buf[r] = '\0';
+
+	fclose(memfile);
+
+	if (r != w) {
+		llen += printf(" written(%d) != read(%d)", w, r);
+		pad_spc(llen, 64, "[FAIL]\n");
+		return 1;
+	}
+
+	llen += printf(" \"%s\" = \"%s\"", expected, buf);
+	ret = strncmp(expected, buf, c);
+
+	pad_spc(llen, 64, ret ? "[FAIL]\n" : " [OK]\n");
+	return ret;
+}
+
+static int run_vfprintf(int min, int max)
+{
+	int test;
+	int tmp;
+	int ret = 0;
+	void *p1, *p2;
+
+	for (test = min; test >= 0 && test <= max; test++) {
+		int llen = 0; /* line length */
+
+		/* avoid leaving empty lines below, this will insert holes into
+		 * test numbers.
+		 */
+		switch (test + __LINE__ + 1) {
+		CASE_TEST(empty);        EXPECT_VFPRINTF(0, "", ""); break;
+		CASE_TEST(simple);       EXPECT_VFPRINTF(3, "foo", "foo"); break;
+		CASE_TEST(string);       EXPECT_VFPRINTF(3, "foo", "%s", "foo"); break;
+		CASE_TEST(number);       EXPECT_VFPRINTF(4, "1234", "%d", 1234); break;
+		CASE_TEST(negnumber);    EXPECT_VFPRINTF(5, "-1234", "%d", -1234); break;
+		CASE_TEST(unsigned);     EXPECT_VFPRINTF(5, "12345", "%u", 12345); break;
+		CASE_TEST(char);         EXPECT_VFPRINTF(1, "c", "%c", 'c'); break;
+		CASE_TEST(hex);          EXPECT_VFPRINTF(1, "f", "%x", 0xf); break;
+		CASE_TEST(pointer);      EXPECT_VFPRINTF(3, "0x1", "%p", (void *) 0x1); break;
+		case __LINE__:
+			return ret; /* must be last */
+		/* note: do not set any defaults so as to permit holes above */
+		}
+	}
+	return ret;
+}
+
 static int smash_stack(void)
 {
 	char buf[100];
+	volatile char *ptr = buf;
+	size_t i;
 
-	for (size_t i = 0; i < 200; i++)
-		buf[i] = 'P';
+	for (i = 0; i < 200; i++)
+		ptr[i] = 'P';
 
 	return 1;
 }
@@ -689,12 +836,20 @@ static int run_protection(int min, int max)
 
 	llen += printf("0 -fstackprotector ");
 
-#if !defined(NOLIBC_STACKPROTECTOR)
+#if !defined(_NOLIBC_STACKPROTECTOR)
 	llen += printf("not supported");
 	pad_spc(llen, 64, "[SKIPPED]\n");
 	return 0;
 #endif
 
+#if defined(_NOLIBC_STACKPROTECTOR)
+	if (!__stack_chk_guard) {
+		llen += printf("__stack_chk_guard not initialized");
+		pad_spc(llen, 64, "[FAIL]\n");
+		return 1;
+	}
+#endif
+
 	pid = -1;
 	pid = fork();
 
@@ -708,6 +863,7 @@ static int run_protection(int min, int max)
 		close(STDOUT_FILENO);
 		close(STDERR_FILENO);
 
+		prctl(PR_SET_DUMPABLE, 0, 0, 0, 0);
 		smash_stack();
 		return 1;
 
@@ -778,6 +934,7 @@ static const struct test test_names[] = {
 	/* add new tests here */
 	{ .name = "syscall",    .func = run_syscall    },
 	{ .name = "stdlib",     .func = run_stdlib     },
+	{ .name = "vfprintf",   .func = run_vfprintf   },
 	{ .name = "protection", .func = run_protection },
 	{ 0 }
 };
@@ -785,7 +942,7 @@ static const struct test test_names[] = {
 int main(int argc, char **argv, char **envp)
 {
 	int min = 0;
-	int max = __INT_MAX__;
+	int max = INT_MAX;
 	int ret = 0;
 	int err;
 	int idx;
@@ -833,7 +990,7 @@ int main(int argc, char **argv, char **envp)
 				 * here, which defaults to the full range.
 				 */
 				do {
-					min = 0; max = __INT_MAX__;
+					min = 0; max = INT_MAX;
 					value = colon;
 					if (value && *value) {
 						colon = strchr(value, ':');
@@ -899,7 +1056,7 @@ int main(int argc, char **argv, char **envp)
 #else
 		else if (ioperm(0x501, 1, 1) == 0)
 #endif
-			asm volatile ("outb %%al, %%dx" :: "d"(0x501), "a"(0));
+			__asm__ volatile ("outb %%al, %%dx" :: "d"(0x501), "a"(0));
 		/* if it does nothing, fall back to the regular panic */
 #endif
 	}