From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- net/rxrpc/misc.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 net/rxrpc/misc.c (limited to 'net/rxrpc/misc.c') diff --git a/net/rxrpc/misc.c b/net/rxrpc/misc.c new file mode 100644 index 000000000..8fcc8139d --- /dev/null +++ b/net/rxrpc/misc.c @@ -0,0 +1,62 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Miscellaneous bits + * + * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include +#include +#include +#include "ar-internal.h" + +/* + * The maximum listening backlog queue size that may be set on a socket by + * listen(). + */ +unsigned int rxrpc_max_backlog __read_mostly = 10; + +/* + * How long to wait before scheduling an ACK with subtype DELAY (in ms). + * + * We use this when we've received new data packets. If those packets aren't + * all consumed within this time we will send a DELAY ACK if an ACK was not + * requested to let the sender know it doesn't need to resend. + */ +unsigned long rxrpc_soft_ack_delay = 1000; + +/* + * How long to wait before scheduling an ACK with subtype IDLE (in ms). + * + * We use this when we've consumed some previously soft-ACK'd packets when + * further packets aren't immediately received to decide when to send an IDLE + * ACK let the other end know that it can free up its Tx buffer space. + */ +unsigned long rxrpc_idle_ack_delay = 500; + +/* + * Receive window size in packets. This indicates the maximum number of + * unconsumed received packets we're willing to retain in memory. Once this + * limit is hit, we should generate an EXCEEDS_WINDOW ACK and discard further + * packets. + */ +unsigned int rxrpc_rx_window_size = 255; + +/* + * Maximum Rx MTU size. This indicates to the sender the size of jumbo packet + * made by gluing normal packets together that we're willing to handle. + */ +unsigned int rxrpc_rx_mtu = RXRPC_JUMBO(46); + +/* + * The maximum number of fragments in a received jumbo packet that we tell the + * sender that we're willing to handle. + */ +unsigned int rxrpc_rx_jumbo_max = 46; + +#ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY +/* + * The delay to inject into packet reception. + */ +unsigned long rxrpc_inject_rx_delay; +#endif -- cgit v1.3.1