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Minchan Kim 3189c82056 zram: do not free pool->size_class
Mike reported kernel goes oops with ltp:zram03 testcase.

  zram: Added device: zram0
  zram0: detected capacity change from 0 to 107374182400
  BUG: unable to handle kernel paging request at 0000306d61727a77
  IP: zs_map_object+0xb9/0x260
  PGD 0
  P4D 0
  Oops: 0000 [#1] SMP
  Dumping ftrace buffer:
     (ftrace buffer empty)
  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)
   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]
  CPU: 6 PID: 12356 Comm: swapon Tainted: G            E   4.13.0.g87b2c3f-default #194
  Hardware name: IBM System x3550 M3 -[7944K3G]-/69Y5698     , BIOS -[D6E150AUS-1.10]- 12/15/2010
  task: ffff880158d2c4c0 task.stack: ffffc90001680000
  RIP: 0010:zs_map_object+0xb9/0x260
  Call Trace:
   zram_bvec_rw.isra.26+0xe8/0x780 [zram]
   zram_rw_page+0x6e/0xa0 [zram]
   bdev_read_page+0x81/0xb0
   do_mpage_readpage+0x51a/0x710
   mpage_readpages+0x122/0x1a0
   blkdev_readpages+0x1d/0x20
   __do_page_cache_readahead+0x1b2/0x270
   ondemand_readahead+0x180/0x2c0
   page_cache_sync_readahead+0x31/0x50
   generic_file_read_iter+0x7e7/0xaf0
   blkdev_read_iter+0x37/0x40
   __vfs_read+0xce/0x140
   vfs_read+0x9e/0x150
   SyS_read+0x46/0xa0
   entry_SYSCALL_64_fastpath+0x1a/0xa5
  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
  RIP: zs_map_object+0xb9/0x260 RSP: ffffc90001683988
  CR2: 0000306d61727a77

He bisected the problem is [1].

After commit cf8e0fedf0 ("mm/zsmalloc: simplify zs_max_alloc_size
handling"), 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.

Link: http://lkml.kernel.org/r/20170725062650.GA12134@bbox
Fixes: cf8e0fedf0 ("mm/zsmalloc: simplify zs_max_alloc_size handling")
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: Mike Galbraith <efault@gmx.de>
Tested-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-02 16:34:47 -07:00
arch parisc: Define CONFIG_CPU_BIG_ENDIAN 2017-07-31 17:51:27 +02:00
block blk-mq: map queues to all present CPUs 2017-07-24 10:01:31 -06:00
certs modsign: add markers to endif-statements in certs/Makefile 2017-07-14 11:01:37 +10:00
crypto crypto: authencesn - Fix digest_null crash 2017-07-18 17:01:11 +08:00
Documentation Merge branch 'for-4.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata 2017-07-31 13:33:21 -07:00
drivers platform-drivers-x86 for v4.13-3 2017-08-02 09:43:28 -07:00
firmware firmware/Makefile: force recompilation if makefile changes 2017-05-08 17:15:10 -07:00
fs More NFS client bugfixes for 4.13 2017-07-28 14:44:56 -07:00
include kthread: fix documentation build warning 2017-08-02 16:34:47 -07:00
init random: do not ignore early device randomness 2017-07-12 16:26:00 -07:00
ipc ipc/util.h: update documentation for ipc_getref() and ipc_putref() 2017-07-12 16:26:02 -07:00
kernel pid: kill pidhash_size in pidhash_init() 2017-08-02 16:34:46 -07:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-07-31 22:36:42 -07:00
mm zram: do not free pool->size_class 2017-08-02 16:34:47 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-07-31 22:36:42 -07:00
samples samples/bpf: fix bpf tunnel cleanup 2017-07-31 22:02:47 -07:00
scripts DeviceTree fixes for 4.13: 2017-07-28 17:21:41 -07:00
security Now that IPC and other changes have landed, enable manual markings for 2017-07-19 08:55:18 -07:00
sound sound fixes for 4.13-rc3 2017-07-27 10:44:28 -07:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-07-31 22:36:42 -07:00
usr ramfs: clarify help text that compression applies to ramfs as well as legacy ramdisk. 2017-07-06 16:24:30 -07:00
virt KVM: make pid available for uevents without debugfs 2017-07-26 18:57:44 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: Add support to generate LLVM assembly files 2017-04-25 08:13:52 +09:00
.mailmap power supply and reset changes for the v4.12 series (part 2) 2017-05-12 12:02:21 -07:00
COPYING
CREDITS avr32: remove support for AVR32 architecture 2017-05-01 09:27:15 +02:00
Kbuild kbuild: Consolidate header generation from ASM offset information 2017-04-13 05:43:37 +09:00
Kconfig
MAINTAINERS Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-07-31 22:36:42 -07:00
Makefile Linux 4.13-rc3 2017-07-30 12:40:36 -07:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.