From nobody Sun Feb 8 22:58:17 2026 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.13]) (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 432A517DFE7 for ; Sun, 25 Jan 2026 02:06:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.13 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769306781; cv=none; b=SBWrX2uMPDQnasH7xKYtyuOmek7QujdTaCfFg+ck8zCanxE0P7gnpnqt0zUquxzw4IE2zsvwealPxkp1v5SqoN7jKunAZ5KFffjmdPDJN1H4fDOWARZwoj+R7oqH0aZuuNv79CflOHxBda463AlypBqPGubFnshz71fRtnXTtL0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769306781; c=relaxed/simple; bh=Poo+TxlExZWqFGtqU5gtnSaaD852RaUcR6E/vWDkTEI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JBZ+Z8WLCW3fd9NtHmWpWGku2LQHlq7dwS/Gs/93i8ovf/s5zZSPwx+jnTG0R1UJ173eaKltlBrMUjipJBw6hoylf53ZuwoDILVkPr4AZm5+n8/s1wHZxAjpFsFuacZ8qAAToapeFkyovrTp+UYYRUe2EfMxQe38icvFTg6CVMQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=kehH28NN; arc=none smtp.client-ip=192.198.163.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="kehH28NN" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1769306779; x=1800842779; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Poo+TxlExZWqFGtqU5gtnSaaD852RaUcR6E/vWDkTEI=; b=kehH28NNESyCtz5X5wOgWKBxdfsXPVMViK9ZnoAddjkmqL8+zaq+XhxI dYUAQ/GHgNhrcJ7WEstWgIHxMmyI1T4ffEzZm5209ug1/m6Q6zZIYmU8A Ki9kqEvFqxT0Jjva/UylsXnTjQ6CEmqbSawvwh7lAM8PbYcx9ALGOCwoA cs3FoYNwyGnLGFPPMOvCX4ukAj6s/6N0isLAzATxqotsGx0DgtD3LQ12R k4WYFju5hX3unntTaqX2R1ax9KUcS4y/JCRsnRKP8+m801EY//hTlpBND OjUTdijW5uaHzdtGHhTd7VhkKYYonv5WXhYBelISzJmvsCqxP88QKGlF2 g==; X-CSE-ConnectionGUID: zADjZVquTICpvj1xxncTvA== X-CSE-MsgGUID: UuBm/45vSB+mcjLj1vBxXw== X-IronPort-AV: E=McAfee;i="6800,10657,11681"; a="73101874" X-IronPort-AV: E=Sophos;i="6.21,252,1763452800"; d="scan'208";a="73101874" Received: from fmviesa009.fm.intel.com ([10.60.135.149]) by fmvoesa107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Jan 2026 18:06:17 -0800 X-CSE-ConnectionGUID: KWDW7o7SQs26lZh16M50MQ== X-CSE-MsgGUID: ZKMAAgXGTbmQ73M8VhZ4Uw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,252,1763452800"; d="scan'208";a="207783096" Received: from chang-linux-3.sc.intel.com (HELO chang-linux-3) ([172.25.66.172]) by fmviesa009.fm.intel.com with ESMTP; 24 Jan 2026 18:06:17 -0800 From: "Chang S. Bae" To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, peterz@infradead.org, david.kaplan@amd.com, chang.seok.bae@intel.com Subject: [PATCH 2/7] x86/apic: Implement self-NMI support Date: Sun, 25 Jan 2026 01:42:17 +0000 Message-ID: <20260125014224.249901-3-chang.seok.bae@intel.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260125014224.249901-1-chang.seok.bae@intel.com> References: <20260125014224.249901-1-chang.seok.bae@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: David Kaplan Add function to send an NMI-to-self which is needed for stop_machine_nmi(). Note that send_IPI_self() cannot be used to send an NMI so send_IPI() is used. Signed-off-by: David Kaplan Signed-off-by: Chang S. Bae --- Updates from the original version: * Rename the subject to highlight arch-side "implementation" --- arch/x86/kernel/apic/ipi.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/kernel/apic/ipi.c b/arch/x86/kernel/apic/ipi.c index 98a57cb4aa86..6d4e5aa27529 100644 --- a/arch/x86/kernel/apic/ipi.c +++ b/arch/x86/kernel/apic/ipi.c @@ -4,6 +4,7 @@ #include #include #include +#include =20 #include =20 @@ -248,6 +249,12 @@ void default_send_IPI_self(int vector) __default_send_IPI_shortcut(APIC_DEST_SELF, vector); } =20 +/* Self-NMI is used in stop_machine_nmi() */ +void arch_send_self_nmi(void) +{ + apic->send_IPI(smp_processor_id(), NMI_VECTOR); +} + #ifdef CONFIG_X86_32 void default_send_IPI_mask_sequence_logical(const struct cpumask *mask, in= t vector) { --=20 2.51.0