From nobody Fri Dec 19 02:17:52 2025 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A82D518EB7; Sat, 16 Dec 2023 12:58:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="D8G7Gs5C"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="1e3LxO2b" Date: Sat, 16 Dec 2023 12:58:51 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1702731532; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=anal0gKvCrGV42YD75/clg9vkB6MDtNjy8h56W2p3PQ=; b=D8G7Gs5C8gU6AHoiYGs3G1YTToFJ+tVgZK4jDaw20+H/C6PTuxzki+2sFGHIkuDHiU8/2r 0HiJb3TKeQ8Tndpp3jyw9mUdN9Qv1Hhq4UP8cEnk3f3OOO6dqWSAjlXQubQ1dj1F9z5tuj 09Cj2M7PUhC5XTgP+AHCzR7+0mIeJumuFcC6pq6xbot/DmQDeQEQ1F0XcFLPVWscXBDowo xe+nkeHSnW60wzSjZSnX4Ykd+EPFs6TS3Qm1j4aDWonjfmeeYH2Ax5tLGWzkmZBMyGilzc mUrmt3R+jtBYo8ldl4LE2CiEdpHxKKMtErnx0/SKsxYLTG40R4nA3XXi6Np1sQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1702731532; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=anal0gKvCrGV42YD75/clg9vkB6MDtNjy8h56W2p3PQ=; b=1e3LxO2bYh4tr7rOHq+BFaJ+rQceGMayRtQL/AVtQcxEUH+yN3tvpy/UYJAeiFQ57BWosb 7CWQvuKR3eNpiNBg== From: "tip-bot2 for Thomas Gleixner" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/urgent] x86/alternatives: Sync core before enabling interrupts Cc: Thomas Gleixner , "Borislav Petkov (AMD)" , "Peter Zijlstra (Intel)" , , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <170273153128.398.15915411825430136039.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the x86/urgent branch of tip: Commit-ID: 3ea1704a92967834bf0e64ca1205db4680d04048 Gitweb: https://git.kernel.org/tip/3ea1704a92967834bf0e64ca1205db468= 0d04048 Author: Thomas Gleixner AuthorDate: Thu, 07 Dec 2023 20:49:24 +01:00 Committer: Borislav Petkov (AMD) CommitterDate: Fri, 15 Dec 2023 19:34:42 +01:00 x86/alternatives: Sync core before enabling interrupts text_poke_early() does: local_irq_save(flags); memcpy(addr, opcode, len); local_irq_restore(flags); sync_core(); That's not really correct because the synchronization should happen before interrupts are re-enabled to ensure that a pending interrupt observes the complete update of the opcodes. It's not entirely clear whether the interrupt entry provides enough serialization already, but moving the sync_core() invocation into interrupt disabled region does no harm and is obviously correct. Fixes: 6fffacb30349 ("x86/alternatives, jumplabel: Use text_poke_early() be= fore mm_init()") Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov (AMD) Acked-by: Peter Zijlstra (Intel) Cc: Link: https://lore.kernel.org/r/ZT6narvE%2BLxX%2B7Be@windriver.com --- arch/x86/kernel/alternative.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 73be393..fd44739 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -1685,8 +1685,8 @@ void __init_or_module text_poke_early(void *addr, con= st void *opcode, } else { local_irq_save(flags); memcpy(addr, opcode, len); - local_irq_restore(flags); sync_core(); + local_irq_restore(flags); =20 /* * Could also do a CLFLUSH here to speed up CPU recovery; but