Commit b0f6c9ac authored May 31, 2021 by Wander Lairson Costa Committed by David S. Miller Jun 01, 2021

netpoll: don't require irqs disabled in rt kernels

write_msg(netconsole.c:836) calls netpoll_send_udp after a call to
spin_lock_irqsave, which normally disables interrupts; but in PREEMPT_RT
this call just locks an rt_mutex without disabling irqs. In this case,
netpoll_send_udp is called with interrupts enabled.

Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent a20af95f

net/core/netpoll.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -36,6 +36,7 @@
		#include <net/ip6_checksum.h>
		#include <asm/unaligned.h>
		#include <trace/events/napi.h>
		#include <linux/kconfig.h>

		/*
		* We maintain a small pool of fully-sized skbs, to make sure the
		@@ -389,6 +390,7 @@ void netpoll_send_udp(struct netpoll np, const char msg, int len)
		static atomic_t ip_ident;
		struct ipv6hdr *ip6h;

		if (!IS_ENABLED(CONFIG_PREEMPT_RT))
		WARN_ON_ONCE(!irqs_disabled());

		udp_len = len + sizeof(*udph);