linux_dsm_epyc7002/fs
Darrick J. Wong 27fb5a72f5 xfs: prohibit fs freezing when using empty transactions
I noticed that fsfreeze can take a very long time to freeze an XFS if
there happens to be a GETFSMAP caller running in the background.  I also
happened to notice the following in dmesg:

------------[ cut here ]------------
WARNING: CPU: 2 PID: 43492 at fs/xfs/xfs_super.c:853 xfs_quiesce_attr+0x83/0x90 [xfs]
Modules linked in: xfs libcrc32c ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 ip_set_hash_ip ip_set_hash_net xt_tcpudp xt_set ip_set_hash_mac ip_set nfnetlink ip6table_filter ip6_tables bfq iptable_filter sch_fq_codel ip_tables x_tables nfsv4 af_packet [last unloaded: xfs]
CPU: 2 PID: 43492 Comm: xfs_io Not tainted 5.6.0-rc4-djw #rc4
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-1ubuntu1 04/01/2014
RIP: 0010:xfs_quiesce_attr+0x83/0x90 [xfs]
Code: 7c 07 00 00 85 c0 75 22 48 89 df 5b e9 96 c1 00 00 48 c7 c6 b0 2d 38 a0 48 89 df e8 57 64 ff ff 8b 83 7c 07 00 00 85 c0 74 de <0f> 0b 48 89 df 5b e9 72 c1 00 00 66 90 0f 1f 44 00 00 41 55 41 54
RSP: 0018:ffffc900030f3e28 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffff88802ac54000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81e4a6f0 RDI: 00000000ffffffff
RBP: ffff88807859f070 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000010 R12: 0000000000000000
R13: ffff88807859f388 R14: ffff88807859f4b8 R15: ffff88807859f5e8
FS:  00007fad1c6c0fc0(0000) GS:ffff88807e000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0c7d237000 CR3: 0000000077f01003 CR4: 00000000001606a0
Call Trace:
 xfs_fs_freeze+0x25/0x40 [xfs]
 freeze_super+0xc8/0x180
 do_vfs_ioctl+0x70b/0x750
 ? __fget_files+0x135/0x210
 ksys_ioctl+0x3a/0xb0
 __x64_sys_ioctl+0x16/0x20
 do_syscall_64+0x50/0x1a0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

These two things appear to be related.  The assertion trips when another
thread initiates a fsmap request (which uses an empty transaction) after
the freezer waited for m_active_trans to hit zero but before the the
freezer executes the WARN_ON just prior to calling xfs_log_quiesce.

The lengthy delays in freezing happen because the freezer calls
xfs_wait_buftarg to clean out the buffer lru list.  Meanwhile, the
GETFSMAP caller is continuing to grab and release buffers, which means
that it can take a very long time for the buffer lru list to empty out.

We fix both of these races by calling sb_start_write to obtain freeze
protection while using empty transactions for GETFSMAP and for metadata
scrubbing.  The other two users occur during mount, during which time we
cannot fs freeze.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-03-26 08:19:24 -07:00
..
9p 9p pull request for inclusion in 5.4 2019-09-27 15:10:34 -07:00
adfs fs/adfs: bigdir: Fix an error code in adfs_fplus_read() 2020-01-25 11:31:59 -05:00
affs affs: fix a memory leak in affs_remount 2019-11-18 14:26:43 +01:00
afs Merge branch 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-02-08 13:26:41 -08:00
autofs Merge branch 'next.autofs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-12-05 17:11:48 -08:00
befs fs: Fill in max and min timestamps in superblock 2019-08-30 07:27:17 -07:00
bfs fs: Fill in max and min timestamps in superblock 2019-08-30 07:27:17 -07:00
btrfs for-5.6-rc2-tag 2020-02-23 09:43:50 -08:00
cachefiles cachefiles: drop direct usage of ->bmap method. 2020-02-03 08:05:56 -05:00
ceph ceph: noacl mount option is effectively ignored 2020-02-11 17:04:40 +01:00
cifs cifs: make sure we do not overflow the max EA buffer size 2020-02-14 11:10:24 -06:00
coda y2038: add inode timestamp clamping 2019-09-19 09:42:37 -07:00
configfs utimes: Clamp the timestamps in notify_change() 2019-12-08 19:10:50 -05:00
cramfs cramfs: switch to use of errofc() et.al. 2020-02-07 14:48:41 -05:00
crypto fscrypt: improve format of no-key names 2020-01-22 14:50:03 -08:00
debugfs Merge branch 'work.recursive_removal' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-02-05 05:09:46 +00:00
devpts devpts_pty_kill(): don't bother with d_delete() 2019-09-03 09:30:56 -04:00
dlm dlm: use SO_SNDTIMEO_NEW instead of SO_SNDTIMEO_OLD 2019-12-18 18:07:31 +01:00
ecryptfs eCryptfs fixes for 5.6-rc3 2020-02-17 21:08:37 -08:00
efivarfs Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
efs fs: Fill in max and min timestamps in superblock 2019-08-30 07:27:17 -07:00
erofs erofs: clean up z_erofs_submit_queue() 2020-01-21 16:46:23 +08:00
exportfs race in exportfs_decode_fh() 2019-11-11 09:21:59 -05:00
ext2 dax fixes 5.6-rc1 2020-02-11 16:52:08 -08:00
ext4 ext4: potential crash on allocation error in ext4_alloc_flex_bg_array() 2020-02-29 17:48:08 -05:00
f2fs Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-02-08 13:04:49 -08:00
fat Merge branch 'imm.timestamp' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-02-05 05:02:42 +00:00
freevxfs fs: Fill in max and min timestamps in superblock 2019-08-30 07:27:17 -07:00
fscache proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
fuse Merge branch 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-02-08 13:26:41 -08:00
gfs2 Merge branch 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-02-08 13:26:41 -08:00
hfs hfs/hfsplus: use 64-bit inode timestamps 2019-12-18 18:07:32 +01:00
hfsplus hfs/hfsplus: use 64-bit inode timestamps 2019-12-18 18:07:32 +01:00
hostfs hostfs: pass 64-bit timestamps to/from user space 2019-12-18 18:07:32 +01:00
hpfs fs: compat_ioctl: move FITRIM emulation into file systems 2019-10-23 17:23:46 +02:00
hugetlbfs hugetlbfs: switch to use of invalfc() 2020-02-07 14:48:42 -05:00
iomap fs: Fix page_mkwrite off-by-one errors 2020-01-06 08:58:23 -08:00
isofs y2038: add inode timestamp clamping 2019-09-19 09:42:37 -07:00
jbd2 jbd2: fix data races at struct journal_head 2020-02-29 13:40:02 -05:00
jffs2 fs_parse: fold fs_parameter_desc/fs_parameter_spec 2020-02-07 14:48:37 -05:00
jfs Trivial cleanup for jfs 2020-02-05 05:28:20 +00:00
kernfs Merge branch 'imm.timestamp' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-02-05 05:02:42 +00:00
lockd proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
minix fs: Fill in max and min timestamps in superblock 2019-08-30 07:27:17 -07:00
nfs NFSv4: Ensure the delegation cred is pinned when we call delegreturn 2020-02-13 16:23:02 -05:00
nfs_common
nfsd Highlights: 2020-02-07 17:50:21 -08:00
nilfs2 fs: compat_ioctl: move FITRIM emulation into file systems 2019-10-23 17:23:46 +02:00
nls
notify fs: call fsnotify_sb_delete after evict_inodes 2019-12-18 00:03:01 -05:00
ntfs utimes: Clamp the timestamps in notify_change() 2019-12-08 19:10:50 -05:00
ocfs2 treewide: remove redundant IS_ERR() before error code check 2020-02-04 03:05:27 +00:00
omfs fs: omfs: Initialize filesystem timestamp ranges 2019-08-30 08:11:25 -07:00
openpromfs Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
orangefs help_next should increase position index 2020-02-04 15:22:04 -05:00
overlayfs ovl: fix lseek overflow on 32bit 2020-02-03 11:41:53 +01:00
proc Merge branch 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-02-08 13:26:41 -08:00
pstore pstore/ram: Regularize prz label allocation lifetime 2020-01-08 17:05:45 -08:00
qnx4 fs: Fill in max and min timestamps in superblock 2019-08-30 07:27:17 -07:00
qnx6 fs: Fill in max and min timestamps in superblock 2019-08-30 07:27:17 -07:00
quota \n 2020-01-30 15:37:41 -08:00
ramfs fs_parse: fold fs_parameter_desc/fs_parameter_spec 2020-02-07 14:48:37 -05:00
reiserfs Merge branch 'akpm' (patches from Andrew) 2020-01-31 12:16:36 -08:00
romfs Merge branch 'work.mount2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-09-19 10:06:57 -07:00
squashfs Merge branch 'work.mount2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-09-19 10:06:57 -07:00
sysfs treewide: remove redundant IS_ERR() before error code check 2020-02-04 03:05:27 +00:00
sysv fs: sysv: Initialize filesystem timestamp ranges 2019-08-30 07:27:18 -07:00
tracefs simple_recursive_removal(): kernel-side rm -rf for ramfs-style filesystems 2019-12-10 22:29:58 -05:00
ubifs Merge branch 'imm.timestamp' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-02-05 05:02:42 +00:00
udf udf: Clarify meaning of f_files in udf_statfs 2020-01-20 13:59:41 +01:00
ufs y2038: add inode timestamp clamping 2019-09-19 09:42:37 -07:00
unicode kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
vboxsf fs: Add VirtualBox guest shared folder (vboxsf) support 2020-02-08 17:34:58 -05:00
verity fs-verity: use u64_to_user_ptr() 2020-01-14 13:28:28 -08:00
xfs xfs: prohibit fs freezing when using empty transactions 2020-03-26 08:19:24 -07:00
zonefs zonefs: select FS_IOMAP 2020-02-26 16:58:15 +09:00
aio.c aio: prevent potential eventfd recursion on poll 2020-02-03 17:27:47 -07:00
anon_inodes.c Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
attr.c utimes: Clamp the timestamps in notify_change() 2019-12-08 19:10:50 -05:00
bad_inode.c
binfmt_aout.c
binfmt_elf_fdpic.c y2038: elfcore: Use __kernel_old_timeval for process times 2019-11-15 14:38:29 +01:00
binfmt_elf.c fs/binfmt_elf.c: coredump: allow process with empty address space to coredump 2020-01-31 10:30:41 -08:00
binfmt_em86.c
binfmt_flat.c fs/binfmt_flat.c: remove set but not used variable 'inode' 2019-07-16 19:23:22 -07:00
binfmt_misc.c Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
binfmt_script.c
block_dev.c block: don't send uevent for empty disk when not invalidating 2019-12-02 18:49:30 -07:00
buffer.c smp: Remove allocation mask from on_each_cpu_cond.*() 2020-01-24 20:40:09 +01:00
char_dev.c chardev: Avoid potential use-after-free in 'chrdev_open()' 2020-01-06 20:10:26 +01:00
compat_binfmt_elf.c y2038: elfcore: Use __kernel_old_timeval for process times 2019-11-15 14:38:29 +01:00
compat.c
coredump.c pipe: use exclusive waits when reading or writing 2020-02-08 11:39:19 -08:00
d_path.c [PATCH] fix d_absolute_path() interplay with fsmount() 2019-08-30 19:31:09 -04:00
dax.c dax: pass NOWAIT flag to iomap_apply 2020-02-05 20:34:32 -08:00
dcache.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-12-08 11:08:28 -08:00
dcookies.c
direct-io.c fs/direct-io.c: include fs/internal.h for missing prototype 2020-01-04 13:55:09 -08:00
drop_caches.c fs: avoid softlockups in s_inodes iterators 2019-12-18 00:03:01 -05:00
eventfd.c eventfd: track eventfd_signal() recursion depth 2020-02-03 17:27:38 -07:00
eventpoll.c eventpoll: support non-blocking do_epoll_ctl() calls 2020-01-29 15:45:47 -07:00
exec.c Merge branch 'akpm' (patches from Andrew) 2020-01-31 12:16:36 -08:00
fcntl.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-12-08 11:08:28 -08:00
fhandle.c fs/handle.c - fix up kerneldoc 2019-08-07 21:51:47 -04:00
file_table.c vfs: Export flush_delayed_fput for use by knfsd. 2019-08-19 11:00:39 -04:00
file.c threads-v5.6 2020-01-29 19:38:34 -08:00
filesystems.c fs_parser: remove fs_parameter_description name field 2020-02-07 14:48:36 -05:00
fs_context.c add prefix to fs_context->log 2020-02-07 14:48:35 -05:00
fs_parser.c turn fs_param_is_... into functions 2020-02-07 14:48:38 -05:00
fs_pin.c switch the remnants of releasing the mountpoint away from fs_pin 2019-07-16 22:52:37 -04:00
fs_struct.c
fs_types.c
fs-writeback.c memcg: fix a crash in wb_workfn when a device disappears 2020-01-31 10:30:36 -08:00
fsopen.c add prefix to fs_context->log 2020-02-07 14:48:35 -05:00
inode.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-02-08 13:04:49 -08:00
internal.h for-5.6/io_uring-vfs-2020-01-29 2020-01-29 18:53:37 -08:00
io_uring.c io_uring: fix 32-bit compatability with sendmsg/recvmsg 2020-02-27 14:17:49 -07:00
io-wq.c io-wq: remove spin-for-work optimization 2020-02-25 08:57:37 -07:00
io-wq.h io-wq: ensure work->task_pid is cleared on init 2020-02-25 13:23:48 -07:00
ioctl.c compat-ioctl fix for v5.6 2020-02-08 13:44:41 -08:00
Kconfig fs: New zonefs file system 2020-02-09 15:51:46 -08:00
Kconfig.binfmt
libfs.c simple_recursive_removal(): kernel-side rm -rf for ramfs-style filesystems 2019-12-10 22:29:58 -05:00
locks.c locks: print unsigned ino in /proc/locks 2019-12-29 09:00:58 -05:00
Makefile fs: New zonefs file system 2020-02-09 15:51:46 -08:00
mbcache.c
mount.h switch the remnants of releasing the mountpoint away from fs_pin 2019-07-16 22:52:37 -04:00
mpage.c fs: move guard_bio_eod() after bio_set_op_attrs 2020-01-09 08:16:12 -07:00
namei.c vfs: fix do_last() regression 2020-02-01 10:36:49 -08:00
namespace.c saner copy_mount_options() 2020-02-03 21:23:33 -05:00
no-block.c
nsfs.c Merge branch 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-01-29 11:20:24 -08:00
open.c fs: make build_open_flags() available internally 2020-01-20 17:01:53 -07:00
pipe.c pipe: make sure to wake up everybody when the last reader/writer closes 2020-02-18 14:34:36 -08:00
pnode.c
pnode.h
posix_acl.c fs/posix_acl.c: fix kernel-doc warnings 2020-01-04 13:55:09 -08:00
proc_namespace.c vfs: subtype handling moved to fuse 2019-09-06 21:28:49 +02:00
read_write.c overlayfs update for 5.6 2020-02-04 11:45:21 +00:00
readdir.c readdir: make user_access_begin() use the real access range 2020-01-23 10:15:28 -08:00
select.c y2038: syscalls: change remaining timeval to __kernel_old_timeval 2019-11-15 14:38:29 +01:00
seq_file.c seq_file: fix problem when seeking mid-record 2019-08-13 16:06:52 -07:00
signalfd.c
splice.c pipe: use exclusive waits when reading or writing 2020-02-08 11:39:19 -08:00
stack.c sched/rt, fs: Use CONFIG_PREEMPTION 2019-12-08 14:37:36 +01:00
stat.c fs: make two stat prep helpers available 2020-01-20 17:03:54 -07:00
statfs.c vfs: Fix EOVERFLOW testing in put_compat_statfs64 2019-10-03 14:21:35 -07:00
super.c fs: call fsnotify_sb_delete after evict_inodes 2019-12-18 00:03:01 -05:00
sync.c
timerfd.c timerfd: Make timerfd_settime() time namespace aware 2020-01-14 12:20:53 +01:00
userfaultfd.c Merge branch 'akpm' (patches from Andrew) 2019-12-01 20:36:41 -08:00
utimes.c utimes: Clamp the timestamps in notify_change() 2019-12-08 19:10:50 -05:00
xattr.c