git: ea8fd844183f - stable/15 - kern/proc: expose reaper PID and subtree root in struct kinfo_proc

The branch stable/15 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=ea8fd844183feb8ff44a32aa30291477e88fe4ae

commit ea8fd844183feb8ff44a32aa30291477e88fe4ae
Author:     GenericRikka <rikka.goering@outlook.de>
AuthorDate: 2026-04-20 23:32:49 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2026-04-27 01:28:59 +0000

    kern/proc: expose reaper PID and subtree root in struct kinfo_proc
    
    PR:     293871
    
    (cherry picked from commit 0f89380a3d208d67698f2d35afd35257e5fdbe09)
---
 lib/libkvm/kvm_proc.c            | 8 ++++++++
 sys/compat/freebsd32/freebsd32.h | 4 +++-
 sys/kern/kern_proc.c             | 4 ++++
 sys/sys/user.h                   | 4 +++-
 4 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/lib/libkvm/kvm_proc.c b/lib/libkvm/kvm_proc.c
index fed483978e62..a952888c9ef0 100644
--- a/lib/libkvm/kvm_proc.c
+++ b/lib/libkvm/kvm_proc.c
@@ -121,6 +121,7 @@ kvm_proclist(kvm_t *kd, int what, int arg, struct proc *p,
 	struct thread mtd;
 	struct proc proc;
 	struct proc pproc;
+	struct proc rproc;
 	struct sysentvec sysent;
 	char svname[KI_EMULNAMELEN];
 	struct thread *td = NULL;
@@ -365,6 +366,13 @@ nopgrp:
 		kp->ki_xstat = KW_EXITCODE(proc.p_xexit, proc.p_xsig);
 		kp->ki_acflag = proc.p_acflag;
 		kp->ki_lock = proc.p_lock;
+		if (KREAD(kd, (u_long)proc.p_reaper, &rproc)) {
+			_kvm_err(kd, kd->program,
+			    "can't read reaper at %p", proc.p_reaper);
+			return (-1);
+		}
+		kp->ki_reaper = rproc.p_pid;
+		kp->ki_reapsubtree = proc.p_reapsubtree;
 		kp->ki_tdev_freebsd11 = kp->ki_tdev; /* truncate */
 
 		/* Per-thread items; iterate as appropriate. */
diff --git a/sys/compat/freebsd32/freebsd32.h b/sys/compat/freebsd32/freebsd32.h
index 1436b630689f..3f5b93859f5c 100644
--- a/sys/compat/freebsd32/freebsd32.h
+++ b/sys/compat/freebsd32/freebsd32.h
@@ -392,8 +392,10 @@ struct kinfo_proc32 {
 	char	ki_emul[KI_EMULNAMELEN+1];
 	char	ki_loginclass[LOGINCLASSLEN+1];
 	char	ki_moretdname[MAXCOMLEN-TDNAMLEN+1];
-	char	ki_sparestrings[46];
+	char	ki_sparestrings[38];
 	int	ki_spareints[KI_NSPARE_INT];
+	pid_t	ki_reaper;
+	pid_t	ki_reapsubtree;
 	freebsd32_uint64_t ki_tdev;
 	int	ki_oncpu;
 	int	ki_lastcpu;
diff --git a/sys/kern/kern_proc.c b/sys/kern/kern_proc.c
index e6541c73ccac..758f54c540ab 100644
--- a/sys/kern/kern_proc.c
+++ b/sys/kern/kern_proc.c
@@ -1237,6 +1237,8 @@ fill_kinfo_proc_pgrp(struct proc *p, struct kinfo_proc *kp)
 		kp->ki_tdev = NODEV;
 		kp->ki_tdev_freebsd11 = kp->ki_tdev; /* truncate */
 	}
+	kp->ki_reaper = p->p_reaper->p_pid;
+	kp->ki_reapsubtree = p->p_reapsubtree;
 }
 
 /*
@@ -1496,6 +1498,8 @@ freebsd32_kinfo_proc_out(const struct kinfo_proc *ki, struct kinfo_proc32 *ki32)
 	CP(*ki, *ki32, ki_fibnum);
 	CP(*ki, *ki32, ki_cr_flags);
 	CP(*ki, *ki32, ki_jid);
+	CP(*ki, *ki32, ki_reaper);
+	CP(*ki, *ki32, ki_reapsubtree);
 	CP(*ki, *ki32, ki_numthreads);
 	CP(*ki, *ki32, ki_tid);
 	CP(*ki, *ki32, ki_pri);
diff --git a/sys/sys/user.h b/sys/sys/user.h
index 59210913f889..e1a3897cd319 100644
--- a/sys/sys/user.h
+++ b/sys/sys/user.h
@@ -186,8 +186,10 @@ struct kinfo_proc {
 	 * front of ki_sparestrings, and ints from the end of ki_spareints.
 	 * That way the spare room from both arrays will remain contiguous.
 	 */
-	char	ki_sparestrings[46];	/* spare string space */
+	char	ki_sparestrings[38];	/* spare string space */
 	int	ki_spareints[KI_NSPARE_INT];	/* spare room for growth */
+	pid_t	ki_reaper;		/* pid of reaper process */
+	pid_t	ki_reapsubtree;		/* reaper subtree id */
 	uint64_t ki_tdev;		/* controlling tty dev */
 	int	ki_oncpu;		/* Which cpu we are on */
 	int	ki_lastcpu;		/* Last cpu we were on */