From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750824AbdGYG0y (ORCPT ); Tue, 25 Jul 2017 02:26:54 -0400 Received: from LGEAMRELO12.lge.com ([156.147.23.52]:37480 "EHLO lgeamrelo12.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750749AbdGYG0x (ORCPT ); Tue, 25 Jul 2017 02:26:53 -0400 X-Original-SENDERIP: 156.147.1.127 X-Original-MAILFROM: minchan@kernel.org X-Original-SENDERIP: 10.177.220.163 X-Original-MAILFROM: minchan@kernel.org Date: Tue, 25 Jul 2017 15:26:50 +0900 From: Minchan Kim To: Mike Galbraith , Andrew Morton Cc: Jerome Marchand , LKML , Nitin Gupta Subject: Re: [zram] ltp inspired explosion - master v4.13-rc1-3-g87b2c3fc6317 Message-ID: <20170725062650.GA12134@bbox> References: <1500283045.7885.37.camel@gmx.de> <1500920221.16574.7.camel@gmx.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1500920221.16574.7.camel@gmx.de> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Mon, Jul 24, 2017 at 08:17:01PM +0200, Mike Galbraith wrote: > Now bisected and verified via revert, the culprit is: > > cf8e0fedf078 mm/zsmalloc: simplify zs_max_alloc_size handling > > Reproducer: ltp::testcases/bin/zram03. > Thanks for the report and bisecting. I believe this patch should fix it. Thanks! >>From 0ffbd3c8769fdf56e2f14908f890f9d1703ed32e Mon Sep 17 00:00:00 2001 From: Minchan Kim Date: Tue, 25 Jul 2017 15:15:18 +0900 Subject: [PATCH] zram: do not free pool->size_class Mike reported kernel goes oops with ltp:zram03 testcase. [ 1449.835161] zram: Added device: zram0 [ 1449.929981] zram0: detected capacity change from 0 to 107374182400 [ 1449.968583] BUG: unable to handle kernel paging request at 0000306d61727a77 [ 1449.975550] IP: zs_map_object+0xb9/0x260 [ 1449.979472] PGD 0 [ 1449.979473] P4D 0 [ 1449.981488] [ 1449.984997] Oops: 0000 [#1] SMP [ 1449.988139] Dumping ftrace buffer: [ 1449.991545] (ftrace buffer empty) [ 1449.995120] Modules linked in: zram(E) xfs(E) libcrc32c(E) btrfs(E) xor(E) raid6_pq(E) loop(E) ebtable_filter(E) ebtables(E) ip6table_filter(E) ip6_tables(E) iptable_filter(E) ip_tables(E) x_tables(E) af_packet(E) br_netfilter(E) bridge(E) stp(E) llc(E) iscsi_ibft(E) iscsi_boot_sysfs(E) nls_iso8859_1(E) nls_cp437(E) vfat(E) fat(E) intel_powerclamp(E) coretemp(E) cdc_ether(E) kvm_intel(E) usbnet(E) mii(E) kvm(E) irqbypass(E) crct10dif_pclmul(E) crc32_pclmul(E) crc32c_intel(E) iTCO_wdt(E) ghash_clmulni_intel(E) bnx2(E) iTCO_vendor_support(E) pcbc(E) ioatdma(E) ipmi_ssif(E) aesni_intel(E) i5500_temp(E) i2c_i801(E) aes_x86_64(E) lpc_ich(E) shpchp(E) mfd_core(E) crypto_simd(E) i7core_edac(E) dca(E) glue_helper(E) cryptd(E) ipmi_si(E) button(E) acpi_cpufreq(E) ipmi_devintf(E) pcspkr(E) ipmi_msghandler(E) [ 1450.065731] nfsd(E) auth_rpcgss(E) nfs_acl(E) lockd(E) grace(E) sunrpc(E) ext4(E) crc16(E) mbcache(E) jbd2(E) sd_mod(E) ata_generic(E) i2c_algo_bit(E) ata_piix(E) drm_kms_helper(E) ahci(E) syscopyarea(E) sysfillrect(E) libahci(E) sysimgblt(E) fb_sys_fops(E) uhci_hcd(E) ehci_pci(E) ttm(E) ehci_hcd(E) libata(E) drm(E) megaraid_sas(E) usbcore(E) sg(E) dm_multipath(E) dm_mod(E) scsi_dh_rdac(E) scsi_dh_emc(E) scsi_dh_alua(E) scsi_mod(E) efivarfs(E) autofs4(E) [last unloaded: zram] [ 1450.107900] CPU: 6 PID: 12356 Comm: swapon Tainted: G E 4.13.0.g87b2c3f-default #194 [ 1450.116760] Hardware name: IBM System x3550 M3 -[7944K3G]-/69Y5698 , BIOS -[D6E150AUS-1.10]- 12/15/2010 [ 1450.126486] task: ffff880158d2c4c0 task.stack: ffffc90001680000 [ 1450.132401] RIP: 0010:zs_map_object+0xb9/0x260 [ 1450.136843] RSP: 0018:ffffc90001683988 EFLAGS: 00010202 [ 1450.142063] RAX: 0000000000000000 RBX: ffff8801547a98d0 RCX: ffff8801211b78b0 [ 1450.149190] RDX: 0000306d61727a2f RSI: 0000000000160000 RDI: ffff8801547a98f8 [ 1450.156317] RBP: ffffc900016839c8 R08: 0000000004db4200 R09: 0000000000000008 [ 1450.163446] R10: ffff880151329260 R11: 0000000000000000 R12: ffff880158f76000 [ 1450.170573] R13: 0000000000000001 R14: 0000000000000000 R15: ffffea0004db4200 [ 1450.177700] FS: 00007fe1b4e8b880(0000) GS:ffff88017f180000(0000) knlGS:0000000000000000 [ 1450.185782] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1450.191522] CR2: 0000306d61727a77 CR3: 0000000154415000 CR4: 00000000000006e0 [ 1450.198649] Call Trace: [ 1450.201103] zram_bvec_rw.isra.26+0xe8/0x780 [zram] [ 1450.205978] zram_rw_page+0x6e/0xa0 [zram] [ 1450.210077] bdev_read_page+0x81/0xb0 [ 1450.213738] do_mpage_readpage+0x51a/0x710 [ 1450.217837] ? lru_cache_add+0xe/0x10 [ 1450.221498] mpage_readpages+0x122/0x1a0 [ 1450.225420] ? I_BDEV+0x20/0x20 [ 1450.228560] ? I_BDEV+0x20/0x20 [ 1450.231702] ? alloc_pages_current+0x6a/0xb0 [ 1450.235971] blkdev_readpages+0x1d/0x20 [ 1450.239805] __do_page_cache_readahead+0x1b2/0x270 [ 1450.244596] ondemand_readahead+0x180/0x2c0 [ 1450.248777] page_cache_sync_readahead+0x31/0x50 [ 1450.253394] generic_file_read_iter+0x7e7/0xaf0 [ 1450.257922] blkdev_read_iter+0x37/0x40 [ 1450.261756] __vfs_read+0xce/0x140 [ 1450.265160] vfs_read+0x9e/0x150 [ 1450.268389] SyS_read+0x46/0xa0 [ 1450.271533] entry_SYSCALL_64_fastpath+0x1a/0xa5 [ 1450.276149] RIP: 0033:0x7fe1b4344270 [ 1450.279724] RSP: 002b:00007ffdb4299f48 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 1450.287287] RAX: ffffffffffffffda RBX: 00007fe1b4604678 RCX: 00007fe1b4344270 [ 1450.294414] RDX: 0000000000010000 RSI: 0000000000db2c00 RDI: 0000000000000006 [ 1450.301541] RBP: 00007fe1b4604620 R08: 0000000000000003 R09: 00007fe1b4604678 [ 1450.308667] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000010030 [ 1450.315794] R13: 0000000000010000 R14: 0000000000002710 R15: 0000000000010011 [ 1450.322920] Code: 81 e6 00 c0 3f 00 81 fe 00 00 16 00 0f 85 9f 01 00 00 0f b7 13 65 ff 05 5e 07 dc 7e 66 c1 ea 02 81 e2 ff 01 00 00 49 8b 54 d4 08 <8b> 4a 48 41 0f af ce 81 e1 ff 0f 00 00 41 89 c9 48 c7 c3 a0 70 [ 1450.341785] RIP: zs_map_object+0xb9/0x260 RSP: ffffc90001683988 [ 1450.347698] CR2: 0000306d61727a77 He bisected the problem is [1]. By [1], zram doesn't use double pointer for pool->size_class any more in zs_create_pool so counter function zs_destroy_pool don't need to free it, either. Otherwise, it does kfree wrong address and then, kernel goes Oops. [1] cf8e0fedf078 mm/zsmalloc: simplify zs_max_alloc_size handling Cc: Jerome Marchand Reported-by: Mike Galbraith Signed-off-by: Minchan Kim --- mm/zsmalloc.c | 1 - 1 file changed, 1 deletion(-) diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index 013eea76685e..308acb9d814b 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -2453,7 +2453,6 @@ void zs_destroy_pool(struct zs_pool *pool) } destroy_cache(pool); - kfree(pool->size_class); kfree(pool->name); kfree(pool); } -- 2.7.4