From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Fri, 4 Jun 2021 17:17:32 +0200
Subject: wireguard: do not use -O3
Patch-mainline: v5.13-rc5
Git-commit: cc5060ca0285efe2728bced399a1955a7ce808b2
References: git-fixes

Apparently, various versions of gcc have O3-related miscompiles. Looking
at the difference between -O2 and -O3 for gcc 11 doesn't indicate
miscompiles, but the difference also doesn't seem so significant for
performance that it's worth risking.

Link: https://lore.kernel.org/lkml/CAHk-=wjuoGyxDhAF8SsrTkN0-YfCx7E6jUN3ikC_tn2AKWTTsA@mail.gmail.com/
Link: https://lore.kernel.org/lkml/CAHmME9otB5Wwxp7H8bR_i2uH2esEMvoBMC8uEXBMH9p0q1s6Bw@mail.gmail.com/
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Cc: stable@vger.kernel.org
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Daniel Wagner <dwagner@suse.de>
---
 drivers/net/wireguard/Makefile |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/drivers/net/wireguard/Makefile
+++ b/drivers/net/wireguard/Makefile
@@ -1,5 +1,4 @@
-ccflags-y := -O3
-ccflags-y += -D'pr_fmt(fmt)=KBUILD_MODNAME ": " fmt'
+ccflags-y := -D'pr_fmt(fmt)=KBUILD_MODNAME ": " fmt'
 ccflags-$(CONFIG_WIREGUARD_DEBUG) += -DDEBUG
 wireguard-y := main.o
 wireguard-y += noise.o