From patchwork Fri Dec 18 06:21:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thiago Jung Bauermann X-Patchwork-Id: 1418102 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4CxzLn3z41z9sWT for ; Fri, 18 Dec 2020 17:22:57 +1100 (AEDT) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=TVpDwF5F; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4CxzLn36qzzDqXr for ; Fri, 18 Dec 2020 17:22:57 +1100 (AEDT) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.ibm.com (client-ip=148.163.158.5; helo=mx0b-001b2d01.pphosted.com; envelope-from=bauerman@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=TVpDwF5F; dkim-atps=neutral Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4CxzKD5l1vzDqQs for ; Fri, 18 Dec 2020 17:21:30 +1100 (AEDT) Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 0BI62Jv6160568; Fri, 18 Dec 2020 01:21:22 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=pp1; bh=v0I4Firm0Qr586y5SeVV+M1N6ptYXQ/oTT7Jl73AOCc=; b=TVpDwF5FoljaNIbcfaOA2Uue9DH85YjBloyDzPkdSiGP4fDVUB3BNjByEvcty24Zeb+s i0TJN9ejdupz1AqxO91WEGudPcsSgwDnOOZSffvE9hE/oZpK+IPuZQbxo4txDERLz6Y2 iSvqGreu9EGHemDOZVhNNTH34viJla0vVhS/TLRrLLFY7UagBN4WXDq8Kh5yTWUVw3GC SeTH5WBBAPI+hUhmC58/mRa3SDpjCiJjtu1x/ra0qWjoZ4fHSqKZSo2K1CN8AihRe9xz WTxDlafekJwNlbxYgrHb9Nh4lDWjwuu7Ydav1bRO5GQtuIIGQAC9Fjh5UDFCY8UsZBkR /w== Received: from ppma01wdc.us.ibm.com (fd.55.37a9.ip4.static.sl-reverse.com [169.55.85.253]) by mx0a-001b2d01.pphosted.com with ESMTP id 35gpkerphc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 18 Dec 2020 01:21:22 -0500 Received: from pps.filterd (ppma01wdc.us.ibm.com [127.0.0.1]) by ppma01wdc.us.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 0BI6FrHK023987; Fri, 18 Dec 2020 06:21:22 GMT Received: from b03cxnp07028.gho.boulder.ibm.com (b03cxnp07028.gho.boulder.ibm.com [9.17.130.15]) by ppma01wdc.us.ibm.com with ESMTP id 35cng9dfyq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 18 Dec 2020 06:21:22 +0000 Received: from b03ledav005.gho.boulder.ibm.com (b03ledav005.gho.boulder.ibm.com [9.17.130.236]) by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 0BI6LLth29426150 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 18 Dec 2020 06:21:21 GMT Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 18B19BE059; Fri, 18 Dec 2020 06:21:21 +0000 (GMT) Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5548CBE054; Fri, 18 Dec 2020 06:21:19 +0000 (GMT) Received: from manicouagan.localdomain.com (unknown [9.85.195.64]) by b03ledav005.gho.boulder.ibm.com (Postfix) with ESMTP; Fri, 18 Dec 2020 06:21:18 +0000 (GMT) From: Thiago Jung Bauermann To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH] powerpc/mm: Limit allocation of SWIOTLB on server machines Date: Fri, 18 Dec 2020 03:21:03 -0300 Message-Id: <20201218062103.76102-1-bauerman@linux.ibm.com> X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.343, 18.0.737 definitions=2020-12-18_03:2020-12-17, 2020-12-18 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 impostorscore=0 phishscore=0 lowpriorityscore=0 suspectscore=0 spamscore=0 malwarescore=0 mlxlogscore=999 adultscore=0 clxscore=1011 mlxscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2012180040 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Satheesh Rajendran , Ram Pai , linux-kernel@vger.kernel.org, Thiago Jung Bauermann Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" On server-class POWER machines, we don't need the SWIOTLB unless we're a secure VM. Nevertheless, if CONFIG_SWIOTLB is enabled we unconditionally allocate it. In most cases this is harmless, but on a few machine configurations (e.g., POWER9 powernv systems with 4 GB area reserved for crashdump kernel) it can happen that memblock can't find a 64 MB chunk of memory for the SWIOTLB and fails with a scary-looking WARN_ONCE: ------------[ cut here ]------------ memblock: bottom-up allocation failed, memory hotremove may be affected WARNING: CPU: 0 PID: 0 at mm/memblock.c:332 memblock_find_in_range_node+0x328/0x340 Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 5.10.0-rc2-orig+ #6 NIP: c000000000442f38 LR: c000000000442f34 CTR: c0000000001e0080 REGS: c000000001def900 TRAP: 0700 Not tainted (5.10.0-rc2-orig+) MSR: 9000000002021033 CR: 28022222 XER: 20040000 CFAR: c00000000014b7b4 IRQMASK: 1 GPR00: c000000000442f34 c000000001defba0 c000000001deff00 0000000000000047 GPR04: 00000000ffff7fff c000000001def828 c000000001def820 0000000000000000 GPR08: 0000001ffc3e0000 c000000001b75478 c000000001b75478 0000000000000001 GPR12: 0000000000002000 c000000002030000 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000002030000 GPR20: 0000000000000000 0000000000010000 0000000000010000 c000000001defc10 GPR24: c000000001defc08 c000000001c91868 c000000001defc18 c000000001c91890 GPR28: 0000000000000000 ffffffffffffffff 0000000004000000 00000000ffffffff NIP [c000000000442f38] memblock_find_in_range_node+0x328/0x340 LR [c000000000442f34] memblock_find_in_range_node+0x324/0x340 Call Trace: [c000000001defba0] [c000000000442f34] memblock_find_in_range_node+0x324/0x340 (unreliable) [c000000001defc90] [c0000000015ac088] memblock_alloc_range_nid+0xec/0x1b0 [c000000001defd40] [c0000000015ac1f8] memblock_alloc_internal+0xac/0x110 [c000000001defda0] [c0000000015ac4d0] memblock_alloc_try_nid+0x94/0xcc [c000000001defe30] [c00000000159c3c8] swiotlb_init+0x78/0x104 [c000000001defea0] [c00000000158378c] mem_init+0x4c/0x98 [c000000001defec0] [c00000000157457c] start_kernel+0x714/0xac8 [c000000001deff90] [c00000000000d244] start_here_common+0x1c/0x58 Instruction dump: 2c230000 4182ffd4 ea610088 ea810090 4bfffe84 39200001 3d42fff4 3c62ff60 3863c560 992a8bfc 4bd0881d 60000000 <0fe00000> ea610088 4bfffd94 60000000 random: get_random_bytes called from __warn+0x128/0x184 with crng_init=0 ---[ end trace 0000000000000000 ]--- software IO TLB: Cannot allocate buffer Unless this is a secure VM the message can actually be ignored, because the SWIOTLB isn't needed. Therefore, let's avoid the SWIOTLB in those cases. Fixes: eae9eec476d1 ("powerpc/pseries/svm: Allocate SWIOTLB buffer anywhere in memory") Signed-off-by: Thiago Jung Bauermann --- arch/powerpc/mm/mem.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index afab328d0887..3af991844145 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -300,7 +300,8 @@ void __init mem_init(void) memblock_set_bottom_up(true); if (is_secure_guest()) svm_swiotlb_init(); - else + /* Server machines don't need SWIOTLB if they're not secure guests. */ + else if (!machine_is(pseries) && !machine_is(powernv)) swiotlb_init(0); #endif