From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Zi Yan" Subject: Re: [bisected a4615d11] Memory DLPAR triggers WARN_ONCE() in mm/page_vma_mapped.c Date: Mon, 11 Sep 2017 10:53:19 -0400 Message-ID: References: <1505123773.10243.9.camel@abdul> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="=_MailMate_BF80F212-8DE9-4981-97D3-E062AB410CE6_="; micalg=pgp-sha512; protocol="application/pgp-signature" Return-path: Received: from mail-by2nam03on0102.outbound.protection.outlook.com ([104.47.42.102]:28306 "EHLO NAM03-BY2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751153AbdIKOx1 (ORCPT ); Mon, 11 Sep 2017 10:53:27 -0400 In-Reply-To: <1505123773.10243.9.camel@abdul> Sender: linux-next-owner@vger.kernel.org List-ID: To: abdul Cc: linuxppc-dev , Anshuman Khandual , Stephen Rothwell , linux-next This is an OpenPGP/MIME signed message (RFC 3156 and 4880). --=_MailMate_BF80F212-8DE9-4981-97D3-E062AB410CE6_= Content-Type: text/plain Hi Abdul, Can you try this patch below? I think I missed that pmd entries can be zapped, so the WARN_ONCE is unnecessary. Thanks. diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index 6a03946469a9..eb462e7db0a9 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -167,8 +167,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) return not_found(pvmw); return true; } - } else - WARN_ONCE(1, "Non present huge pmd without pmd migration enabled!"); + } return not_found(pvmw); } else { /* THP pmd was split under us: handle on pte level */ -- Best Regards Yan Zi On 11 Sep 2017, at 5:56, abdul wrote: > Hi, > > Memory DLPAR operation on PowerVM booted withnext-20170907, results in > below warning message. > > Machine Type: Power 8 PowerVM LPAR > Kernel version : 4.13.0-next-20170907 > gcc: 5.2.1 > config : attached > > Steps to recreate: > ---------------------- > Perform dlpar memory add/remove in a loop using 'drmgr' command > > $ drmgr -c mem -d 5 -w 30 -r > $ drmgr -c mem -d 5 -w 30 -a > > after few iterations of add / remove dmes shows below warning > > > dmesg logs: > ------------------ > Non present huge pmd without pmd migration enabled! > ------------[ cut here ]------------ > WARNING: CPU: 14 PID: 5110 at mm/page_vma_mapped.c:171 > page_vma_mapped_walk+0x9a8/0xa10 > Modules linked in: rpadlpar_io(E) rpaphp(E) xt_addrtype(E) > xt_conntrack(E) ipt_MASQUERADE(E) nf_nat_masquerade_ipv4(E) > iptable_nat(E) nf_conntrack_ipv4(E) nf_defrag_ipv4(E) nf_nat_ipv4(E) > iptable_filter(E) ip_tables(E) x_tables(E) nf_nat(E) nf_conntrack(E) > bridge(E) stp(E) llc(E) dm_thin_pool(E) dm_persistent_data(E) > dm_bio_prison(E) dm_bufio(E) libcrc32c(E) pseries_rng(E) rtc_generic(E) > vmx_crypto(E) autofs4(E) > CPU: 14 PID: 5110 Comm: stress Tainted: G E > 4.13.0-next-20170907-autotest #1 > task: c000000760755900 task.stack: c0000007749b4000 > NIP: c000000000316078 LR: c000000000316074 CTR: c000000000c244b0 > REGS: c0000007749b7160 TRAP: 0700 Tainted: G E > (4.13.0-next-20170907-autotest) > MSR: 8000000000029033 CR: 28242282 XER: > 20000000 > CFAR: c000000000182064 SOFTE: 1 > GPR00: c000000000316074 c0000007749b73e0 c000000001599900 > 0000000000000033 > GPR04: 0000000000000000 0000000000000000 6c62616e65206e6f > c000000001769900 > GPR08: 000000077edd0000 0000000000000000 0000000000000000 > c08000049d002386 > GPR12: 0000000000002200 c00000000e749300 f000000001274020 > c00000077ff5e100 > GPR16: c00000077ff54600 c00000077ff64600 f000000001274000 > c0000007749b7650 > GPR20: 0000000000000000 c0000000032ec800 c0000007735bf5c8 > 000000007ffdab00 > GPR24: 000000007ffdabff c00000000173e970 0000000000000001 > c0000007605b0000 > GPR28: f000000001274000 c0000007605b0064 f000000001274000 > c0000007749b74b0 > NIP [c000000000316078] page_vma_mapped_walk+0x9a8/0xa10 > LR [c000000000316074] page_vma_mapped_walk+0x9a4/0xa10 > Call Trace: > [c0000007749b73e0] [c000000000316074] page_vma_mapped_walk+0x9a4/0xa10 > (unreliable) > [c0000007749b7490] [c00000000031792c] page_referenced_one+0xcc/0x250 > [c0000007749b7520] [c00000000031841c] rmap_walk_anon+0x15c/0x380 > [c0000007749b7590] [c00000000031afdc] page_referenced+0x1bc/0x250 > [c0000007749b7620] [c0000000002d0ebc] shrink_active_list+0x24c/0x5a0 > [c0000007749b7720] [c0000000002d1850] shrink_node_memcg+0x640/0x790 > [c0000007749b7820] [c0000000002d1ad8] shrink_node+0x138/0x410 > [c0000007749b78e0] [c0000000002d1ec8] do_try_to_free_pages+0x118/0x490 > [c0000007749b7970] [c0000000002d2350] try_to_free_pages+0x110/0x2b0 > [c0000007749b7a00] [c0000000002b8ab4] __alloc_pages_nodemask > +0x724/0x1120 > [c0000007749b7bf0] [c000000000342c78] alloc_pages_vma+0xb8/0x290 > [c0000007749b7c60] [c0000000003075b0] __handle_mm_fault+0x1150/0x1ad0 > [c0000007749b7d40] [c000000000308058] handle_mm_fault+0x128/0x210 > [c0000007749b7d80] [c0000000000671f8] __do_page_fault+0x218/0x8e0 > [c0000007749b7e30] [c00000000000a4a4] handle_page_fault+0x18/0x38 > Instruction dump: > 2fa80000 409e0044 3cc2fff5 8926743d 2f890000 409ef6ec 3c62ff91 39200001 > 3863ce18 9926743d 4be6bfa5 60000000 <0fe00000> 4bfff6cc 7c0004ac > 39400000 > ---[ end trace c9b04ac31031ebc8 ]--- > > > WARN_ONCE() was introduced by commit a4615d115 ( mm: thp: enable thp > migration in generic path) > > > Regard's > Abdul Haleem > IBM Linux Technology Center --=_MailMate_BF80F212-8DE9-4981-97D3-E062AB410CE6_= Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- Comment: GPGTools - https://gpgtools.org iQEcBAEBCgAGBQJZtqNfAAoJEEGLLxGcTqbMOL0H/RPRmoWN1RaU5+0lClVPChrX py3wzCp+MQo00PwZZE8a/3Xl+oJuXXRpAkXg1FF/td8NwHyprojE8hNSZZdIS61O S7Ujdpx3lgGEvyxgREeAHw3H7NcUDGcqCeg4WwUflhNKKQaSGva8lVZ4yWBOckNJ hmYyqUyd8G1KUi8bCJrcHeyreJoAPmuT1OEcox7V/SNyul6gMSLtHEqGAjGm2sI4 edyxMOdbtfNTSFsX0LSYOXX4SxDHgSiN1Tv5O/7V2jXdJ/qUuDX5efQb6exORt9V Onck612IUKi/VcfNBZAqxr39Jsgp6E/9czvgWUVBcBEWemImXXCtCqWcUmZs+9Y= =9Lsl -----END PGP SIGNATURE----- --=_MailMate_BF80F212-8DE9-4981-97D3-E062AB410CE6_=--