From patchwork Fri Sep 20 13:05:21 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Laurent Dufour X-Patchwork-Id: 11154433 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E653D16B1 for ; Fri, 20 Sep 2019 13:05:46 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B306220665 for ; Fri, 20 Sep 2019 13:05:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B306220665 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 94A8F6B0006; Fri, 20 Sep 2019 09:05:43 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 8AC816B0007; Fri, 20 Sep 2019 09:05:43 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 727BB6B0008; Fri, 20 Sep 2019 09:05:43 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0023.hostedemail.com [216.40.44.23]) by kanga.kvack.org (Postfix) with ESMTP id 4C3E86B0006 for ; Fri, 20 Sep 2019 09:05:43 -0400 (EDT) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id EE2A8181AC9BA for ; Fri, 20 Sep 2019 13:05:42 +0000 (UTC) X-FDA: 75955320924.03.spot45_6c0d5e67a2d3d X-Spam-Summary: 2,0,0,065af2366bbad019,d41d8cd98f00b204,ldufour@linux.ibm.com,:mpe@ellerman.id.au:benh@kernel.crashing.org:paulus@samba.org:aneesh.kumar@linux.ibm.com:npiggin@gmail.com:linuxppc-dev@lists.ozlabs.org::linux-kernel@vger.kernel.org,RULES_HIT:2:41:355:379:541:960:968:973:988:989:1260:1261:1311:1314:1345:1381:1437:1515:1535:1605:1606:1730:1747:1777:1792:2393:2553:2559:2562:2693:3138:3139:3140:3141:3142:3865:3866:3867:3868:3870:3871:3874:4119:4250:4321:5007:6119:6238:6261:7875:8603:8660:9010:10004:11026:11473:11658:11914:12043:12048:12219:12291:12296:12297:12438:12555:12679:12895:12986:13141:13148:13153:13161:13228:13229:13230:13869:13870:13894:14096:14394:21080:21212:21433:21451:21524:21627:21740:30005:30054:30056:30060:30070:30074:30090,0,RBL:148.163.158.5:@linux.ibm.com:.lbl8.mailshell.net-62.2.0.100 64.100.201.201,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:25,LUA_SUMMARY:none X-HE-Tag: spot45_6c0d5e67a2d3d X-Filterd-Recvd-Size: 8282 Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by imf48.hostedemail.com (Postfix) with ESMTP for ; Fri, 20 Sep 2019 13:05:42 +0000 (UTC) Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x8KD5cE8169861 for ; Fri, 20 Sep 2019 09:05:41 -0400 Received: from e06smtp04.uk.ibm.com (e06smtp04.uk.ibm.com [195.75.94.100]) by mx0b-001b2d01.pphosted.com with ESMTP id 2v4wjtcp2a-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 20 Sep 2019 09:05:40 -0400 Received: from localhost by e06smtp04.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Fri, 20 Sep 2019 14:05:27 +0100 Received: from d06av25.portsmouth.uk.ibm.com (d06av25.portsmouth.uk.ibm.com [9.149.105.61]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x8KD5PkD56557750 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 20 Sep 2019 13:05:25 GMT Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id AEA9111C066; Fri, 20 Sep 2019 13:05:25 +0000 (GMT) Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E2A2511C04C; Fri, 20 Sep 2019 13:05:24 +0000 (GMT) Received: from pomme.com (unknown [9.145.3.52]) by d06av25.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 20 Sep 2019 13:05:24 +0000 (GMT) From: Laurent Dufour To: mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org, aneesh.kumar@linux.ibm.com, npiggin@gmail.com, linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 0/2] powerpc/mm: Conditionally call H_BLOCK_REMOVE Date: Fri, 20 Sep 2019 15:05:21 +0200 X-Mailer: git-send-email 2.23.0 MIME-Version: 1.0 X-TM-AS-GCONF: 00 x-cbid: 19092013-0016-0000-0000-000002AE913D X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19092013-0017-0000-0000-0000330F465C Message-Id: <20190920130523.20441-1-ldufour@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-09-20_04:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=864 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1909200126 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Since the commit ba2dd8a26baa ("powerpc/pseries/mm: call H_BLOCK_REMOVE"), the call to H_BLOCK_REMOVE is always done if the feature is exhibited. However, the hypervisor may not support all the block size for the hcall H_BLOCK_REMOVE depending on the segment base page size and actual page size. When unsupported block size is used, the hcall H_BLOCK_REMOVE is returning H_PARAM, which is triggering a BUG_ON check leading to a panic like this: kernel BUG at /home/srikar/work/linux.git/arch/powerpc/platforms/pseries/lpar.c:466! Oops: Exception in kernel mode, sig: 5 [#1] BE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: CPU: 28 PID: 583 Comm: modprobe Not tainted 5.2.0-master #5 NIP: c0000000000be8dc LR: c0000000000be880 CTR: 0000000000000000 REGS: c0000007e77fb130 TRAP: 0700 Not tainted (5.2.0-master) MSR: 8000000000029032 CR: 42224824 XER: 20000000 CFAR: c0000000000be8fc IRQMASK: 0 GPR00: 0000000022224828 c0000007e77fb3c0 c000000001434d00 0000000000000005 GPR04: 9000000004fa8c00 0000000000000000 0000000000000003 0000000000000001 GPR08: c0000007e77fb450 0000000000000000 0000000000000001 ffffffffffffffff GPR12: c0000007e77fb450 c00000000edfcb80 0000cd7d3ea30000 c0000000016022b0 GPR16: 00000000000000b0 0000cd7d3ea30000 0000000000000001 c080001f04f00105 GPR20: 0000000000000003 0000000000000004 c000000fbeb05f58 c000000001602200 GPR24: 0000000000000000 0000000000000004 8800000000000000 c000000000c5d148 GPR28: c000000000000000 8000000000000000 a000000000000000 c0000007e77fb580 NIP [c0000000000be8dc] .call_block_remove+0x12c/0x220 LR [c0000000000be880] .call_block_remove+0xd0/0x220 Call Trace: [c0000007e77fb3c0] [c000000fb8c00240] 0xc000000fb8c00240 (unreliable) [c0000007e77fb4e0] [c0000000000bfef8] .pSeries_lpar_flush_hash_range+0x578/0x670 [c0000007e77fb660] [c000000000073994] .flush_hash_range+0x44/0x100 [c0000007e77fb700] [c00000000007667c] .__flush_tlb_pending+0x3c/0xc0 [c0000007e77fb780] [c0000000002d3fdc] .zap_pte_range+0x7ec/0x830 [c0000007e77fb8d0] [c0000000002d4524] .unmap_page_range+0x3f4/0x540 [c0000007e77fb9f0] [c0000000002d4a04] .unmap_vmas+0x94/0x120 [c0000007e77fbab0] [c0000000002e0efc] .exit_mmap+0xac/0x1f0 [c0000007e77fbbc0] [c0000000000fae1c] .mmput+0x9c/0x1f0 [c0000007e77fbc40] [c000000000105738] .do_exit+0x388/0xd60 [c0000007e77fbd20] [c0000000001061b4] .do_group_exit+0x54/0x100 [c0000007e77fbdb0] [c000000000106274] .__se_sys_exit_group+0x14/0x20 [c0000007e77fbe20] [c00000000000b688] system_call+0x5c/0x70 Instruction dump: 39400001 38a00000 4800003c 60000000 60420000 7fa9e800 38e00000 419e0014 7d29d278 7d290074 7929d182 69270001 <0b070000> 7d495378 394a0001 7fa93040 The PAPR document specifies the TLB Block Invalidate Characteristics which tells for each pair of segment base page size, actual page size, the size of the block the hcall H_BLOCK_REMOVE is supporting (cf Power Architecture Platform Requirements +, Section 7.3.16.23, page 252). Supporting various block sizes doesn't seem needed at that time since all systems I was able to play with was supporting an 8 addresses block size, which is the maximum through the hcall, or none at all. Supporting various size would complexify the algorithm in call_block_remove() so unless this is required, this is not done. In the case of block size different from 8, a warning message is displayed at boot time and that block size will be ignored checking for the H_BLOCK_REMOVE support. Due to the minimal amount of hardware showing a limited set of H_BLOCK_REMOVE supported page size, I don't think there is a need to push this series to the stable mailing list. The first patch is reading the characteristic through the hcall ibm,get-system-parameter and record the supported block size for each page size. The second patch is changing the check used to detect the H_BLOCK_REMOVE availability to take care of the base page size and page size couple. Fixes: ba2dd8a26baa ("powerpc/pseries/mm: call H_BLOCK_REMOVE") Changes since V2: - Adressing Michael's comments - Remove some unedeed logging - Replace "hblkr" prefix/suffix to "hlkbrm" - In pseries_lpar_read_hblkrm_characteristics() - Remove unneeded buffer's initialisation - Limit endianness trouble - Prevent potential buffer overflow. Changes since V1: - Addressing Aneesh's comments - Remove penc initialisation, this is already done in mmu_psize_set_default_penc() - Add details on the TLB Block Invalidate Characteristics's buffer format - Introduce #define instead of using direct numerical values - Function reading the characteristics is now directly called from pSeries_setup_arch() - The characteristics are now stored in a dedciated table static to lpar.c Laurent Dufour (2): powperc/mm: read TLB Block Invalidate Characteristics powerpc/mm: call H_BLOCK_REMOVE when supported arch/powerpc/platforms/pseries/lpar.c | 162 ++++++++++++++++++++++- arch/powerpc/platforms/pseries/pseries.h | 1 + arch/powerpc/platforms/pseries/setup.c | 1 + 3 files changed, 162 insertions(+), 2 deletions(-)