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Zhang Xiaoxu 5f7ca306c7 cifs: Fix double add page to memcg when cifs_readpages
[ Upstream commit 95a3d8f3af ]

When xfstests generic/451, there is an BUG at mm/memcontrol.c:
  page:ffffea000560f2c0 refcount:2 mapcount:0 mapping:000000008544e0ea
       index:0xf
  mapping->aops:cifs_addr_ops dentry name:"tst-aio-dio-cycle-write.451"
  flags: 0x2fffff80000001(locked)
  raw: 002fffff80000001 ffffc90002023c50 ffffea0005280088 ffff88815cda0210
  raw: 000000000000000f 0000000000000000 00000002ffffffff ffff88817287d000
  page dumped because: VM_BUG_ON_PAGE(page->mem_cgroup)
  page->mem_cgroup:ffff88817287d000
  ------------[ cut here ]------------
  kernel BUG at mm/memcontrol.c:2659!
  invalid opcode: 0000 [#1] SMP
  CPU: 2 PID: 2038 Comm: xfs_io Not tainted 5.8.0-rc1 #44
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_
    073836-buildvm-ppc64le-16.ppc.4
  RIP: 0010:commit_charge+0x35/0x50
  Code: 0d 48 83 05 54 b2 02 05 01 48 89 77 38 c3 48 c7
        c6 78 4a ea ba 48 83 05 38 b2 02 05 01 e8 63 0d9
  RSP: 0018:ffffc90002023a50 EFLAGS: 00010202
  RAX: 0000000000000000 RBX: ffff88817287d000 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: ffff88817ac97ea0 RDI: ffff88817ac97ea0
  RBP: ffffea000560f2c0 R08: 0000000000000203 R09: 0000000000000005
  R10: 0000000000000030 R11: ffffc900020237a8 R12: 0000000000000000
  R13: 0000000000000001 R14: 0000000000000001 R15: ffff88815a1272c0
  FS:  00007f5071ab0800(0000) GS:ffff88817ac80000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 000055efcd5ca000 CR3: 000000015d312000 CR4: 00000000000006e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   mem_cgroup_charge+0x166/0x4f0
   __add_to_page_cache_locked+0x4a9/0x710
   add_to_page_cache_locked+0x15/0x20
   cifs_readpages+0x217/0x1270
   read_pages+0x29a/0x670
   page_cache_readahead_unbounded+0x24f/0x390
   __do_page_cache_readahead+0x3f/0x60
   ondemand_readahead+0x1f1/0x470
   page_cache_async_readahead+0x14c/0x170
   generic_file_buffered_read+0x5df/0x1100
   generic_file_read_iter+0x10c/0x1d0
   cifs_strict_readv+0x139/0x170
   new_sync_read+0x164/0x250
   __vfs_read+0x39/0x60
   vfs_read+0xb5/0x1e0
   ksys_pread64+0x85/0xf0
   __x64_sys_pread64+0x22/0x30
   do_syscall_64+0x69/0x150
   entry_SYSCALL_64_after_hwframe+0x44/0xa9
  RIP: 0033:0x7f5071fcb1af
  Code: Bad RIP value.
  RSP: 002b:00007ffde2cdb8e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000011
  RAX: ffffffffffffffda RBX: 00007ffde2cdb990 RCX: 00007f5071fcb1af
  RDX: 0000000000001000 RSI: 000055efcd5ca000 RDI: 0000000000000003
  RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000001000 R11: 0000000000000293 R12: 0000000000000001
  R13: 000000000009f000 R14: 0000000000000000 R15: 0000000000001000
  Modules linked in:
  ---[ end trace 725fa14a3e1af65c ]---

Since commit 3fea5a499d ("mm: memcontrol: convert page cache to a new
mem_cgroup_charge() API") not cancel the page charge, the pages maybe
double add to pagecache:
thread1                       | thread2
cifs_readpages
readpages_get_pages
 add_to_page_cache_locked(head,index=n)=0
                              | readpages_get_pages
                              | add_to_page_cache_locked(head,index=n+1)=0
 add_to_page_cache_locked(head, index=n+1)=-EEXIST
 then, will next loop with list head page's
 index=n+1 and the page->mapping not NULL
readpages_get_pages
add_to_page_cache_locked(head, index=n+1)
 commit_charge
  VM_BUG_ON_PAGE

So, we should not do the next loop when any page add to page cache
failed.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-01 13:14:48 +02:00
arch x86/speculation/mds: Mark mds_user_clear_cpu_buffers() __always_inline 2020-10-01 13:14:48 +02:00
block block: ensure bdi->io_pages is always initialized 2020-09-12 13:40:22 +02:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto crypto: af_alg - fix use-after-free in af_alg_accept() due to bh_lock_sock() 2020-07-09 09:37:10 +02:00
Documentation dt-bindings: sound: wm8994: Correct required supplies based on actual implementaion 2020-10-01 13:14:43 +02:00
drivers vfio/pci: Clear error and request eventfd ctx after releasing 2020-10-01 13:14:48 +02:00
firmware Fix built-in early-load Intel microcode alignment 2020-01-23 08:21:29 +01:00
fs cifs: Fix double add page to memcg when cifs_readpages 2020-10-01 13:14:48 +02:00
include NFS: Fix races nfs_page_group_destroy() vs nfs_destroy_unlinked_subrequests() 2020-10-01 13:14:41 +02:00
init printk: queue wake_up_klogd irq_work only if per-CPU areas are ready 2020-07-22 09:32:13 +02:00
ipc ipc/util.c: sysvipc_find_ipc() incorrectly updates position index 2020-05-20 08:18:40 +02:00
kernel printk: handle blank console arguments passed in. 2020-10-01 13:14:45 +02:00
lib lib/string.c: implement stpcpy 2020-10-01 13:14:25 +02:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm mm/swap_state: fix a data race in swapin_nr_pages 2020-10-01 13:14:47 +02:00
net tipc: fix memory leak in service subscripting 2020-10-01 13:14:44 +02:00
samples samples: bpf: Fix build error 2020-06-03 08:19:31 +02:00
scripts checkpatch: fix the usage of capture group ( ... ) 2020-09-09 19:04:32 +02:00
security selinux: sel_avc_get_stat_idx should increase position index 2020-10-01 13:14:33 +02:00
sound ASoC: img-i2s-out: Fix runtime PM imbalance on error 2020-10-01 13:14:47 +02:00
tools perf kcore_copy: Fix module map when there are no modules loaded 2020-10-01 13:14:47 +02:00
usr initramfs: restore default compression behavior 2020-04-13 10:44:59 +02:00
virt KVM: arm64: vgic-its: Fix memory leak on the error path of vgic_add_lpi() 2020-10-01 13:14:42 +02:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +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 updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS Documentation/llvm: add documentation on building w/ Clang/LLVM 2020-09-26 18:01:31 +02:00
Makefile Linux 4.19.148 2020-09-26 18:01:33 +02:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

Linux kernel
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