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Qian Cai 0c81585499 mm/page_ext.c: fix an imbalance with kmemleak
After offlining a memory block, kmemleak scan will trigger a crash, as
it encounters a page ext address that has already been freed during
memory offlining.  At the beginning in alloc_page_ext(), it calls
kmemleak_alloc(), but it does not call kmemleak_free() in
free_page_ext().

    BUG: unable to handle kernel paging request at ffff888453d00000
    PGD 128a01067 P4D 128a01067 PUD 128a04067 PMD 47e09e067 PTE 800ffffbac2ff060
    Oops: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
    CPU: 1 PID: 1594 Comm: bash Not tainted 5.0.0-rc8+ #15
    Hardware name: HP ProLiant DL180 Gen9/ProLiant DL180 Gen9, BIOS U20 10/25/2017
    RIP: 0010:scan_block+0xb5/0x290
    Code: 85 6e 01 00 00 48 b8 00 00 30 f5 81 88 ff ff 48 39 c3 0f 84 5b 01 00 00 48 89 d8 48 c1 e8 03 42 80 3c 20 00 0f 85 87 01 00 00 <4c> 8b 3b e8 f3 0c fa ff 4c 39 3d 0c 6b 4c 01 0f 87 08 01 00 00 4c
    RSP: 0018:ffff8881ec57f8e0 EFLAGS: 00010082
    RAX: 0000000000000000 RBX: ffff888453d00000 RCX: ffffffffa61e5a54
    RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888453d00000
    RBP: ffff8881ec57f920 R08: fffffbfff4ed588d R09: fffffbfff4ed588c
    R10: fffffbfff4ed588c R11: ffffffffa76ac463 R12: dffffc0000000000
    R13: ffff888453d00ff9 R14: ffff8881f80cef48 R15: ffff8881f80cef48
    FS:  00007f6c0e3f8740(0000) GS:ffff8881f7680000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: ffff888453d00000 CR3: 00000001c4244003 CR4: 00000000001606a0
    Call Trace:
     scan_gray_list+0x269/0x430
     kmemleak_scan+0x5a8/0x10f0
     kmemleak_write+0x541/0x6ca
     full_proxy_write+0xf8/0x190
     __vfs_write+0xeb/0x980
     vfs_write+0x15a/0x4f0
     ksys_write+0xd2/0x1b0
     __x64_sys_write+0x73/0xb0
     do_syscall_64+0xeb/0xaaa
     entry_SYSCALL_64_after_hwframe+0x44/0xa9
    RIP: 0033:0x7f6c0dad73b8
    Code: 89 02 48 c7 c0 ff ff ff ff eb b3 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 65 63 2d 00 8b 00 85 c0 75 17 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 41 54 49 89 d4 55
    RSP: 002b:00007ffd5b863cb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
    RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f6c0dad73b8
    RDX: 0000000000000005 RSI: 000055a9216e1710 RDI: 0000000000000001
    RBP: 000055a9216e1710 R08: 000000000000000a R09: 00007ffd5b863840
    R10: 000000000000000a R11: 0000000000000246 R12: 00007f6c0dda9780
    R13: 0000000000000005 R14: 00007f6c0dda4740 R15: 0000000000000005
    Modules linked in: nls_iso8859_1 nls_cp437 vfat fat kvm_intel kvm irqbypass efivars ip_tables x_tables xfs sd_mod ahci libahci igb i2c_algo_bit libata i2c_core dm_mirror dm_region_hash dm_log dm_mod efivarfs
    CR2: ffff888453d00000
    ---[ end trace ccf646c7456717c5 ]---
    Kernel panic - not syncing: Fatal exception
    Shutting down cpus with NMI
    Kernel Offset: 0x24c00000 from 0xffffffff81000000 (relocation range:
    0xffffffff80000000-0xffffffffbfffffff)
    ---[ end Kernel panic - not syncing: Fatal exception ]---

Link: http://lkml.kernel.org/r/20190227173147.75650-1-cai@lca.pw
Signed-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05 21:07:21 -08:00
arch docs/core-api/mm: fix user memory accessors formatting 2019-03-05 21:07:20 -08:00
block for-linus-20190215 2019-02-15 09:12:28 -08:00
certs kbuild: remove redundant target cleaning on failure 2019-01-06 09:46:51 +09:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-03-05 09:09:55 -08:00
Documentation mm: remove zone_lru_lock() function, access ->lru_lock directly 2019-03-05 21:07:21 -08:00
drivers agp: efficeon: no need to set PG_reserved on GATT tables 2019-03-05 21:07:18 -08:00
firmware kbuild: change filechk to surround the given command with { } 2019-01-06 09:46:51 +09:00
fs mm/memfd: add an F_SEAL_FUTURE_WRITE seal to memfd 2019-03-05 21:07:19 -08:00
include mm: remove zone_lru_lock() function, access ->lru_lock directly 2019-03-05 21:07:21 -08:00
init mm: replace all open encodings for NUMA_NO_NODE 2019-03-05 21:07:14 -08:00
ipc ipc: introduce ksys_ipc()/compat_ksys_ipc() for s390 2019-01-18 09:33:18 +01:00
kernel kernel: cgroup: add poll file operation 2019-03-05 21:07:17 -08:00
lib mm/page_owner: move config option to mm/Kconfig.debug 2019-03-05 21:07:18 -08:00
LICENSES This is a fairly typical cycle for documentation. There's some welcome 2018-10-24 18:01:11 +01:00
mm mm/page_ext.c: fix an imbalance with kmemleak 2019-03-05 21:07:21 -08:00
net mm: replace all open encodings for NUMA_NO_NODE 2019-03-05 21:07:14 -08:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2019-03-05 08:26:13 -08:00
scripts scripts/decode_stacktrace.sh: handle RIP address with segment 2019-03-05 21:07:13 -08:00
security get rid of legacy 'get_ds()' function 2019-03-04 10:50:14 -08:00
sound sound fixes for 5.0 2019-02-20 09:42:52 -08:00
tools tmpfs: test link accounting with O_TMPFILE 2019-03-05 21:07:20 -08:00
usr user/Makefile: Fix typo and capitalization in comment section 2018-12-11 00:18:03 +09:00
virt kvm: properly check debugfs dentry before using it 2019-02-28 08:57:32 -08:00
.clang-format clang-format: Update .clang-format with the latest for_each macro list 2019-01-19 19:26:06 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: Add support for DT binding schema checks 2018-12-13 09:41:32 -06:00
.mailmap .mailmap: Add Mathieu Othacehe 2019-02-21 11:41:19 +00:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS CREDITS/MAINTAINERS: Retire parisc-linux.org email domain 2019-02-21 20:16:10 +01:00
Kbuild kbuild: use assignment instead of define ... endef for filechk_* rules 2019-01-06 10:22:35 +09:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS MAINTAINERS: add entry for memblock 2019-03-05 21:07:20 -08:00
Makefile Linux 5.0 2019-03-03 15:21:29 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

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.