? diff.txt
? arch/amd64/compile/GENERIC
? arch/amd64/conf/GENERIC.local
Index: compat/linux/arch/amd64/linux_syscall.h
===================================================================
RCS file: /cvsroot/src/sys/compat/linux/arch/amd64/linux_syscall.h,v
retrieving revision 1.85
diff -u -r1.85 linux_syscall.h
--- compat/linux/arch/amd64/linux_syscall.h	26 Oct 2025 16:25:16 -0000	1.85
+++ compat/linux/arch/amd64/linux_syscall.h	8 Nov 2025 00:58:52 -0000
@@ -1,4 +1,4 @@
-/* $NetBSD: linux_syscall.h,v 1.85 2025/10/26 16:25:16 christos Exp $ */
+/* $NetBSD$ */
 
 /*
  * System call numbers.
@@ -471,6 +471,9 @@
 /* syscall: "__sysctl" ret: "int" args: "struct linux___sysctl *" */
 #define	LINUX_SYS___sysctl	156
 
+/* syscall: "__prctl" ret: "int" args: "int" "..." */
+#define	LINUX_SYS___prctl	157
+
 /* syscall: "arch_prctl" ret: "int" args: "int" "unsigned long" */
 #define	LINUX_SYS_arch_prctl	158
 
Index: compat/linux/arch/amd64/linux_syscallargs.h
===================================================================
RCS file: /cvsroot/src/sys/compat/linux/arch/amd64/linux_syscallargs.h,v
retrieving revision 1.85
diff -u -r1.85 linux_syscallargs.h
--- compat/linux/arch/amd64/linux_syscallargs.h	26 Oct 2025 16:25:16 -0000	1.85
+++ compat/linux/arch/amd64/linux_syscallargs.h	8 Nov 2025 00:58:53 -0000
@@ -1,4 +1,4 @@
-/* $NetBSD: linux_syscallargs.h,v 1.85 2025/10/26 16:25:16 christos Exp $ */
+/* $NetBSD$ */
 
 /*
  * System call argument lists.
@@ -652,6 +652,11 @@
 };
 check_syscall_args(linux_sys___sysctl)
 
+struct linux_sys___prctl_args {
+	syscallarg(int) code;
+	syscallarg(void *) args[SYS_MAXSYSARGS];
+};
+
 struct linux_sys_arch_prctl_args {
 	syscallarg(int) code;
 	syscallarg(unsigned long) addr;
@@ -1648,6 +1653,8 @@
 
 int	linux_sys___sysctl(struct lwp *, const struct linux_sys___sysctl_args *, register_t *);
 
+int	linux_sys___prctl(struct lwp *, const struct linux_sys___prctl_args *, register_t *);
+
 int	linux_sys_arch_prctl(struct lwp *, const struct linux_sys_arch_prctl_args *, register_t *);
 
 int	linux_sys_setrlimit(struct lwp *, const struct linux_sys_setrlimit_args *, register_t *);
Index: compat/linux/arch/amd64/linux_syscalls.c
===================================================================
RCS file: /cvsroot/src/sys/compat/linux/arch/amd64/linux_syscalls.c,v
retrieving revision 1.85
diff -u -r1.85 linux_syscalls.c
--- compat/linux/arch/amd64/linux_syscalls.c	26 Oct 2025 16:25:16 -0000	1.85
+++ compat/linux/arch/amd64/linux_syscalls.c	8 Nov 2025 00:58:53 -0000
@@ -1,4 +1,4 @@
-/* $NetBSD: linux_syscalls.c,v 1.85 2025/10/26 16:25:16 christos Exp $ */
+/* $NetBSD$ */
 
 /*
  * System call names.
@@ -8,7 +8,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: linux_syscalls.c,v 1.85 2025/10/26 16:25:16 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD$");
 
 #if defined(_KERNEL_OPT)
 #if defined(_KERNEL_OPT)
@@ -227,7 +227,7 @@
 	/* 154 */	"modify_ldt",
 	/* 155 */	"#155 (unimplemented pivot_root)",
 	/* 156 */	"__sysctl",
-	/* 157 */	"#157 (unimplemented prctl)",
+	/* 157 */	"__prctl",
 	/* 158 */	"arch_prctl",
 	/* 159 */	"#159 (unimplemented adjtimex)",
 	/* 160 */	"setrlimit",
@@ -771,7 +771,7 @@
 	/* 154 */	NULL, /* modify_ldt */
 	/* 155 */	NULL, /* unimplemented pivot_root */
 	/* 156 */	NULL, /* __sysctl */
-	/* 157 */	NULL, /* unimplemented prctl */
+	/* 157 */	NULL, /* __prctl */
 	/* 158 */	NULL, /* arch_prctl */
 	/* 159 */	NULL, /* unimplemented adjtimex */
 	/* 160 */	NULL, /* setrlimit */
Index: compat/linux/arch/amd64/linux_sysent.c
===================================================================
RCS file: /cvsroot/src/sys/compat/linux/arch/amd64/linux_sysent.c,v
retrieving revision 1.85
diff -u -r1.85 linux_sysent.c
--- compat/linux/arch/amd64/linux_sysent.c	26 Oct 2025 16:25:16 -0000	1.85
+++ compat/linux/arch/amd64/linux_sysent.c	8 Nov 2025 00:58:53 -0000
@@ -1,4 +1,4 @@
-/* $NetBSD: linux_sysent.c,v 1.85 2025/10/26 16:25:16 christos Exp $ */
+/* $NetBSD$ */
 
 /*
  * System call switch table.
@@ -8,7 +8,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: linux_sysent.c,v 1.85 2025/10/26 16:25:16 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD$");
 
 #if defined(_KERNEL_OPT)
 #include "opt_sysv.h"
@@ -793,8 +793,10 @@
 		.sy_call = (sy_call_t *)linux_sys___sysctl
 	},		/* 156 = __sysctl */
 	{
-		.sy_call = linux_sys_nosys,
-	},		/* 157 = filler */
+		ns(struct linux_sys___prctl_args),
+		.sy_flags = SYCALL_ARG_PTR | SYCALL_INDIRECT,
+		.sy_call = (sy_call_t *)linux_sys___prctl
+	},		/* 157 = __prctl */
 	{
 		ns(struct linux_sys_arch_prctl_args),
 		.sy_call = (sy_call_t *)linux_sys_arch_prctl
Index: compat/linux/arch/amd64/linux_systrace_args.c
===================================================================
RCS file: /cvsroot/src/sys/compat/linux/arch/amd64/linux_systrace_args.c,v
retrieving revision 1.29
diff -u -r1.29 linux_systrace_args.c
--- compat/linux/arch/amd64/linux_systrace_args.c	26 Oct 2025 16:25:16 -0000	1.29
+++ compat/linux/arch/amd64/linux_systrace_args.c	8 Nov 2025 00:58:54 -0000
@@ -1,4 +1,4 @@
-/* $NetBSD: linux_systrace_args.c,v 1.29 2025/10/26 16:25:16 christos Exp $ */
+/* $NetBSD$ */
 
 /*
  * System call argument to DTrace register array conversion.
@@ -1230,6 +1230,14 @@
 		*n_args = 1;
 		break;
 	}
+	/* linux_sys___prctl */
+	case 157: {
+		const struct linux_sys___prctl_args *p = params;
+		iarg[0] = SCARG(p, code); /* int */
+		uarg[1] = (intptr_t) SCARG(p, args[0]); /* void * */
+		*n_args = 2;
+		break;
+	}
 	/* linux_sys_arch_prctl */
 	case 158: {
 		const struct linux_sys_arch_prctl_args *p = params;
@@ -4187,6 +4195,19 @@
 			break;
 		};
 		break;
+	/* linux_sys___prctl */
+	case 157:
+		switch(ndx) {
+		case 0:
+			p = "int";
+			break;
+		case 1:
+			p = "void *";
+			break;
+		default:
+			break;
+		};
+		break;
 	/* linux_sys_arch_prctl */
 	case 158:
 		switch(ndx) {
@@ -6614,6 +6635,11 @@
 		if (ndx == 0 || ndx == 1)
 			p = "int";
 		break;
+	/* linux_sys___prctl */
+	case 157:
+		if (ndx == 0 || ndx == 1)
+			p = "int";
+		break;
 	/* linux_sys_arch_prctl */
 	case 158:
 		if (ndx == 0 || ndx == 1)
Index: compat/linux/arch/amd64/syscalls.master
===================================================================
RCS file: /cvsroot/src/sys/compat/linux/arch/amd64/syscalls.master,v
retrieving revision 1.76
diff -u -r1.76 syscalls.master
--- compat/linux/arch/amd64/syscalls.master	26 Oct 2025 16:19:05 -0000	1.76
+++ compat/linux/arch/amd64/syscalls.master	8 Nov 2025 00:58:55 -0000
@@ -340,7 +340,8 @@
 			    size_t bytecount); }
 155	UNIMPL		pivot_root
 156	STD		{ int|linux_sys||__sysctl(struct linux___sysctl *lsp); }
-157	UNIMPL		prctl
+157	INDIR		{ int|linux_sys||__prctl(int code, \
+                                  ... void * args[SYS_MAXSYSARGS]); }
 158	STD		{ int|linux_sys||arch_prctl(int code, \
 			    unsigned long addr); }
 159	UNIMPL		adjtimex
Index: compat/linux/common/linux_sched.c
===================================================================
RCS file: /cvsroot/src/sys/compat/linux/common/linux_sched.c,v
retrieving revision 1.85
diff -u -r1.85 linux_sched.c
--- compat/linux/common/linux_sched.c	19 Sep 2025 19:35:15 -0000	1.85
+++ compat/linux/common/linux_sched.c	8 Nov 2025 00:58:55 -0000
@@ -782,3 +782,78 @@
 
 	return sys__sched_setaffinity(l, &ssa, retval);
 }
+
+int
+linux_sys___prctl(struct lwp *l, const struct linux_sys___prctl_args *uap,
+    register_t *retval)
+{
+	/* {
+		syscallarg(int)    code;
+		syscallarg(void *) args[SYS_MAXSYSARGS];
+	} */
+
+        /* linux prctl truncates name to 16 bytes */
+	size_t len = 16;
+	lwpid_t target = l->l_lid;
+	proc_t *p = curproc;
+	lwp_t *t;
+	unsigned int c = SCARG(uap, code);
+	int error;
+
+        /* TODO: add other commonly used prctl codes */
+        switch(c) {
+        case 15: { // PR_SET_NAME
+	        char *name, *oname;
+		name = kmem_alloc(len, KM_SLEEP);
+		error = copyinstr(SCARG(uap, args[0]), name, len, NULL);
+		switch (error) {
+		case ENAMETOOLONG:
+		case 0:
+			name[len - 1] = '\0';
+			break;
+		default:
+			kmem_free(name, len);
+			return error;
+		}
+	
+		p = curproc;
+		mutex_enter(p->p_lock);
+		if ((t = lwp_find(p, target)) == NULL) {
+			mutex_exit(p->p_lock);
+			kmem_free(name, len);
+			return ESRCH;
+		}
+		lwp_lock(t);
+		oname = t->l_name;
+		t->l_name = name;
+		lwp_unlock(t);
+		mutex_exit(p->p_lock);
+	
+		if (oname != NULL)
+			kmem_free(oname, len);
+	
+		return 0;
+	}
+
+        case 16: {  // PR_GET_NAME
+	        char name[len];
+		mutex_enter(p->p_lock);
+		if ((t = lwp_find(p, target)) == NULL) {
+			mutex_exit(p->p_lock);
+			return ESRCH;
+		}
+		lwp_lock(t);
+		if (t->l_name == NULL)
+			name[0] = '\0';
+		else
+			strlcpy(name, t->l_name, sizeof(name));
+		lwp_unlock(t);
+		mutex_exit(p->p_lock);
+	
+		return copyoutstr(name, SCARG(uap, args[0]), len, NULL);
+		}
+	default:
+		return 0;	
+	}
+
+}