From nobody Mon Feb 9 04:13:45 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org ARC-Seal: i=1; a=rsa-sha256; t=1587100019; cv=none; d=zohomail.com; s=zohoarc; b=kuQPvlb+bO5sAvaj9tUE/XLGpB8L0wjjSBGMKNzamgvA+I/hEiPg+MOUpkhZwIfAcQF1qo0zmUCotCkeEkTA2nbV8Rt97IVfJ9frDyMbbU8XbatmSiYx2/A4JWg6db+WdMnpobq+Jq7JtkCfa+zO898bZJRUx7zHBuvC1TNH2vY= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1587100019; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=As1kjkA008H+MqCx9ZgXGTO1Szi6X4P5IU6M4E34dFg=; b=Q9W+vzFgUqFtMSK1uOybGVaZy2rt1z6I6kaw8cSaXpCsbBtalcsPWMc/U/R85ioU7RNWX45gO5Soh4cl+VnQ//nSLtf48OGBIknWkNBka8ynwLEFd+19qe6g90MnzdDdTMT+mM7zA/a7vtuGcJQjU1/v6tyxff2x+B9pLOUaEt0= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1587100019210956.5892949892591; Thu, 16 Apr 2020 22:06:59 -0700 (PDT) Received: from localhost ([::1]:42508 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jPJDN-0001vz-WE for importer@patchew.org; Fri, 17 Apr 2020 01:06:58 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53913) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jPJBz-0000gl-Ay for qemu-devel@nongnu.org; Fri, 17 Apr 2020 01:05:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1jPJBy-0007SL-1g for qemu-devel@nongnu.org; Fri, 17 Apr 2020 01:05:31 -0400 Received: from bilbo.ozlabs.org ([203.11.71.1]:41189 helo=ozlabs.org) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1jPJBv-0007RU-Of; Fri, 17 Apr 2020 01:05:29 -0400 Received: by ozlabs.org (Postfix, from userid 1007) id 493PDM4l3Qz9sSs; Fri, 17 Apr 2020 15:05:23 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gibson.dropbear.id.au; s=201602; t=1587099923; bh=uB/pOlpSyK6RnSOjkZjsdS+Li7f3wH6cGmH3QFWMPrI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=l1LpHJNMi1JpK3kAh+psr5CQ4+vCUXfSVY1xMnVfUf4q/1nfCEgEu2qsCFjnQT1df eDv7h/2Yp+J8V4bTDT+phm29dnqr/F3dVu44tUTzPhjF1PBLEQ8bczpLdPg1oA4G+w NDvICM03UopTp5K7Sg30kNWDy0PjFhA8Q5pi8SSo= From: David Gibson To: peter.maydell@linaro.org Subject: [PULL 2/3] target/ppc: Fix wrong interpretation of the disposition flag. Date: Fri, 17 Apr 2020 15:05:13 +1000 Message-Id: <20200417050514.235060-3-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.25.2 In-Reply-To: <20200417050514.235060-1-david@gibson.dropbear.id.au> References: <20200417050514.235060-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 203.11.71.1 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-devel@nongnu.org, groug@kaod.org, Ganesh Goudar , clg@kaod.org, qemu-ppc@nongnu.org, David Gibson Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" From: Ganesh Goudar Bitwise AND with kvm_run->flags to evaluate if we recovered from MCE or not is not correct, As disposition in kvm_run->flags is a two-bit integer value and not a bit map, So check for equality instead of bitwise AND. Without the fix qemu treats any unrecoverable mce error as recoverable and ends up in a mce loop inside the guest, Below are the MCE logs before and after the fix. Before fix: [ 66.775757] MCE: CPU0: Initiator CPU [ 66.775891] MCE: CPU0: Unknown [ 66.776587] MCE: CPU0: machine check (Harmless) Host UE Indeterminate [R= ecovered] [ 66.776857] MCE: CPU0: NIP: [c0080000000e00b8] mcetest_tlbie+0xb0/0x128 = [mcetest_tlbie] After fix: [ 20.650577] CPU: 0 PID: 1415 Comm: insmod Tainted: G M O 5.6.0-fwnmi-arv+ = #11 [ 20.650618] NIP: c0080000023a00e8 LR: c0080000023a00d8 CTR: c000000000021f= e0 [ 20.650660] REGS: c0000001fffd3d70 TRAP: 0200 Tainted: G M O (5.6.0-fwnmi-= arv+) [ 20.650708] MSR: 8000000002a0b033 CR: 42= 000222 XER: 20040000 [ 20.650758] CFAR: c00000000000b940 DAR: c0080000025e00e0 DSISR: 00000200 I= RQMASK: 0 [ 20.650758] GPR00: c0080000023a00d8 c0000001fddd79a0 c0080000023a8500 0000= 000000000039 [ 20.650758] GPR04: 0000000000000001 0000000000000000 0000000000000000 0000= 000000000007 [ 20.650758] GPR08: 0000000000000007 c0080000025e00e0 0000000000000000 0000= 0000000000f7 [ 20.650758] GPR12: 0000000000000000 c000000001900000 c00000000101f398 c008= 0000025c052f [ 20.650758] GPR16: 00000000000003a8 c0080000025c0000 c0000001fddd7d70 c000= 0000015b7940 [ 20.650758] GPR20: 000000000000fff1 c000000000f72c28 c0080000025a0988 0000= 000000000000 [ 20.650758] GPR24: 0000000000000100 c0080000023a05d0 c0000000001f1d70 0000= 000000000000 [ 20.650758] GPR28: c0000001fde20000 c0000001fd02b2e0 c0080000023a0000 c008= 0000025e0000 [ 20.651178] NIP [c0080000023a00e8] mcetest_tlbie+0xe8/0xf0 [mcetest_tlbie] [ 20.651220] LR [c0080000023a00d8] mcetest_tlbie+0xd8/0xf0 [mcetest_tlbie] [ 20.651262] Call Trace: [ 20.651280] [c0000001fddd79a0] [c0080000023a00d8] mcetest_tlbie+0xd8/0xf0 = [mcetest_tlbie] (unreliable) [ 20.651340] [c0000001fddd7a10] [c00000000001091c] do_one_initcall+0x6c/0x2= c0 [ 20.651390] [c0000001fddd7af0] [c0000000001f7998] do_init_module+0x90/0x298 [ 20.651433] [c0000001fddd7b80] [c0000000001f61a8] load_module+0x1f58/0x27a0 [ 20.651476] [c0000001fddd7d40] [c0000000001f6c70] __do_sys_finit_module+0x= e0/0x100 [ 20.651526] [c0000001fddd7e20] [c00000000000b9d0] system_call+0x5c/0x68 [ 20.651567] Instruction dump: [ 20.651594] e8410018 3c620000 e8638020 480000cd e8410018 3c620000 e8638028= 480000bd [ 20.651646] e8410018 7be904e4 39400000 612900e0 <7d434a64> 4bffff74 3c4c00= 01 38428410 [ 20.651699] ---[ end trace 4c40897f016b4340 ]--- [ 20.653310] Bus error [ 20.655575] MCE: CPU0: machine check (Harmless) Host UE Indeterminate [Not= recovered] [ 20.655575] MCE: CPU0: NIP: [c0080000023a00e8] mcetest_tlbie+0xe8/0xf0 [mc= etest_tlbie] [ 20.655576] MCE: CPU0: Initiator CPU [ 20.655576] MCE: CPU0: Unknown Signed-off-by: Ganesh Goudar Message-Id: <20200408170944.16003-1-ganeshgr@linux.ibm.com> Signed-off-by: David Gibson --- target/ppc/kvm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c index 03d0667e8f..2692f76130 100644 --- a/target/ppc/kvm.c +++ b/target/ppc/kvm.c @@ -2816,11 +2816,11 @@ int kvm_arch_msi_data_to_gsi(uint32_t data) #if defined(TARGET_PPC64) int kvm_handle_nmi(PowerPCCPU *cpu, struct kvm_run *run) { - bool recovered =3D run->flags & KVM_RUN_PPC_NMI_DISP_FULLY_RECOV; + uint16_t flags =3D run->flags & KVM_RUN_PPC_NMI_DISP_MASK; =20 cpu_synchronize_state(CPU(cpu)); =20 - spapr_mce_req_event(cpu, recovered); + spapr_mce_req_event(cpu, flags =3D=3D KVM_RUN_PPC_NMI_DISP_FULLY_RECOV= ); =20 return 0; } --=20 2.25.2