git: 18905fc31b31 - main - sysctl net.inet.tcp.ktcplist: try to handle EDEADLK

The branch main has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=18905fc31b31fd72a1a1918b26ebbf6c4f0fb5aa

commit 18905fc31b31fd72a1a1918b26ebbf6c4f0fb5aa
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2025-07-03 17:59:30 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2025-07-10 14:42:27 +0000

    sysctl net.inet.tcp.ktcplist: try to handle EDEADLK
    
    If EDEADLK is returned from the locked handler, restart it.  Do it
    limited number of times.  Catch signals between tries.
    
    Reviewed by:    glebius, markj
    Sponsored by:   Nvidia networking
    Differential revision:  https://reviews.freebsd.org/D51143
---
 sys/netinet/tcp_subr.c | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c
index f8811649fe19..45048fb3848d 100644
--- a/sys/netinet/tcp_subr.c
+++ b/sys/netinet/tcp_subr.c
@@ -2869,21 +2869,28 @@ tcp_ktlslist_locked(SYSCTL_HANDLER_ARGS, bool export_keys)
 
 	zfree(buf, M_TEMP);
 	return (error);
-
-again_reset:
-	req->oldidx = 0;
-	goto again;
 }
 
 static int
 tcp_ktlslist1(SYSCTL_HANDLER_ARGS, bool export_keys)
 {
-	int res;
-
-	sx_xlock(&ktlslist_lock);
-	res = tcp_ktlslist_locked(oidp, arg1, arg2, req, export_keys);
-	sx_xunlock(&ktlslist_lock);
-	return (res);
+	int repeats, error;
+
+	for (repeats = 0; repeats < 100; repeats++) {
+		if (sx_xlock_sig(&ktlslist_lock))
+			return (EINTR);
+		error = tcp_ktlslist_locked(oidp, arg1, arg2, req,
+		    export_keys);
+		sx_xunlock(&ktlslist_lock);
+		if (error != EDEADLK)
+			break;
+		if (sig_intr() != 0) {
+			error = EINTR;
+			break;
+		}
+		req->oldidx = 0;
+	}
+	return (error);
 }
 	
 static int