From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B88C7C433ED for ; Sat, 15 May 2021 06:25:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 82FE5613DA for ; Sat, 15 May 2021 06:25:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230514AbhEOG0h (ORCPT ); Sat, 15 May 2021 02:26:37 -0400 Received: from terminus.zytor.com ([198.137.202.136]:42231 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229980AbhEOG0e (ORCPT ); Sat, 15 May 2021 02:26:34 -0400 Received: from [IPv6:2601:646:8602:8be1:e512:4e99:5d16:dcc6] ([IPv6:2601:646:8602:8be1:e512:4e99:5d16:dcc6]) (authenticated bits=0) by mail.zytor.com (8.16.1/8.15.2) with ESMTPSA id 14F6P2uK3245252 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO); Fri, 14 May 2021 23:25:06 -0700 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.zytor.com 14F6P2uK3245252 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2021042801; t=1621059906; bh=K2JDn0iVIHW+Qwi8Co3+G0Lt201NrH/X9imNdm2N4FY=; h=Date:In-Reply-To:References:Subject:To:CC:From:From; b=mphwezTPdEDxoESNYe9uWi/iKoIcOfKQRzSrM/gyp+UBmAcQTOCYhauxv5wWaAGEd OwDDlzmPKJiTKhXVJ06y4RZgqcEebdDUw8KqDH2DL3MMv/XPP+FyVJ/t5jNe6DQjJ+ k3VBDpqQmVMfumGfVYy+zfBEwgeJf/K1MSbzpoQq8HKwBFCEWmUywUpUS39+TC4HPG 15Tlvt6IZINmKCp7Q8iqqar3f9rPNTdjV4BFbKfyv/scDzMCJlZaJznVRL9G/6oZFd xMNAewZocnaGe55sfBAcalCBIF6T1QB13kxGETDY7cCamteWSoSkxq5B78yr4hJ/7W 7K6WB8kmwrSWw== Date: Fri, 14 May 2021 23:24:53 -0700 User-Agent: K-9 Mail for Android In-Reply-To: <20210515014400.2999028-8-hpa@zytor.com> References: <20210515014400.2999028-1-hpa@zytor.com> <20210515014400.2999028-8-hpa@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH v2 7/9] x86/irq: WARN_ONCE() if irq_move_cleanup is called on a pending interrupt To: Thomas Gleixner , Ingo Molnar , Andy Lutomirski , Borislav Petkov , "H. Peter Anvin" CC: Linux Kernel Mailing List From: "H. Peter Anvin" Message-ID: <09189009-FB0A-4DFA-917E-F447EB21798D@zytor.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ugh=2E=2E=2E I could swear I had fixed the patch description=2E On May 14, 2021 6:43:59 PM PDT, "H=2E Peter Anvin" wrote= : >From: "H=2E Peter Anvin (Intel)" > >The current IRQ vector allocation code should be "clean" and never >issue a IRQ_MOVE_CLEANUP_VECTOR IPI for an interrupt that could still >be pending=2E This should make it possible to move it to the "normal" >system IRQ vector range=2E This should probably be a three-step process: > >1=2E Introduce this WARN_ONCE() on this event ever occurring=2E >2=2E Move the IRQ_MOVE_CLEANUP_VECTOR to the sysvec range=2E >3=2E Remove the self-IPI hack=2E > >This implements step 1=2E > >Suggested-by: Thomas Gleixner >Signed-off-by: H=2E Peter Anvin (Intel) >--- > arch/x86/kernel/apic/vector=2Ec | 5 +++++ > 1 file changed, 5 insertions(+) > >diff --git a/arch/x86/kernel/apic/vector=2Ec >b/arch/x86/kernel/apic/vector=2Ec >index 6dbdc7c22bb7=2E=2E7ba2982a3585 100644 >--- a/arch/x86/kernel/apic/vector=2Ec >+++ b/arch/x86/kernel/apic/vector=2Ec >@@ -939,9 +939,14 @@ DEFINE_IDTENTRY_SYSVEC(sysvec_irq_move_cleanup) > * to this CPU=2E IRQ_MOVE_CLEANUP_VECTOR is the lowest > * priority external vector, so on return from this > * interrupt the device interrupt will happen first=2E >+ * >+ * *** This should never happen with the current IRQ >+ * cleanup code, so WARN_ONCE() for now, and >+ * eventually get rid of this hack=2E > */ > irr =3D apic_read(APIC_IRR + (vector / 32 * 0x10)); > if (irr & (1U << (vector % 32))) { >+ WARN_ONCE(1, "irq_move_cleanup called on still pending >interrupt\n"); > apic->send_IPI_self(IRQ_MOVE_CLEANUP_VECTOR); > continue; > } --=20 Sent from my Android device with K-9 Mail=2E Please excuse my brevity=2E