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* Merge tag 'ovl-update-5.6' of ↵Linus Torvalds2020-02-0412-228/+505
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull overlayfs update from Miklos Szeredi: - Try to preserve holes in sparse files when copying up, thus saving disk space and improving performance. - Fix a performance regression introduced in v4.19 by preserving asynchronicity of IO when fowarding to underlying layers. Add VFS helpers to submit async iocbs. - Fix a regression in lseek(2) introduced in v4.19 that breaks >2G seeks on 32bit kernels. - Fix a corner case where st_ino/st_dev was not preserved across copy up. - Miscellaneous fixes and cleanups. * tag 'ovl-update-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: fix lseek overflow on 32bit ovl: add splice file read write helper ovl: implement async IO routines vfs: add vfs_iocb_iter_[read|write] helper functions ovl: layer is const ovl: fix corner case of non-constant st_dev;st_ino ovl: fix corner case of conflicting lower layer uuid ovl: generalize the lower_fs[] array ovl: simplify ovl_same_sb() helper ovl: generalize the lower_layers[] array ovl: improving copy-up efficiency for big sparse file ovl: use ovl_inode_lock in ovl_llseek() ovl: use pr_fmt auto generate prefix ovl: fix wrong WARN_ON() in ovl_cache_update_ino()
| * ovl: fix lseek overflow on 32bitMiklos Szeredi2020-02-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | ovl_lseek() is using ssize_t to return the value from vfs_llseek(). On a 32-bit kernel ssize_t is a 32-bit signed int, which overflows above 2 GB. Assign the return value of vfs_llseek() to loff_t to fix this. Reported-by: Boris Gjenero <boris.gjenero@gmail.com> Fixes: 9e46b840c705 ("ovl: support stacked SEEK_HOLE/SEEK_DATA") Cc: <stable@vger.kernel.org> # v4.19 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: add splice file read write helperMurphy Zhou2020-01-241-0/+47
| | | | | | | | | | | | | | | | | | | | | | Now overlayfs falls back to use default file splice read and write, which is not compatiple with overlayfs, returning EFAULT. xfstests generic/591 can reproduce part of this. Tested this patch with xfstests auto group tests. Signed-off-by: Murphy Zhou <jencce.kernel@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: implement async IO routinesJiufei Xue2020-01-243-15/+110
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A performance regression was observed since linux v4.19 with aio test using fio with iodepth 128 on overlayfs. The queue depth of the device was always 1 which is unexpected. After investigation, it was found that commit 16914e6fc7e1 ("ovl: add ovl_read_iter()") and commit 2a92e07edc5e ("ovl: add ovl_write_iter()") resulted in vfs_iter_{read,write} being called on underlying filesystem, which always results in syncronous IO. Implement async IO for stacked reading and writing. This resolves the performance regresion. This is implemented by allocating a new kiocb for submitting the AIO request on the underlying filesystem. When the request is completed, the new kiocb is freed and the completion callback is called on the original iocb. Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * vfs: add vfs_iocb_iter_[read|write] helper functionsJiufei Xue2020-01-241-0/+56
| | | | | | | | | | | | | | | | This doesn't cause any behavior changes and will be used by overlay async IO implementation. Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: layer is constMiklos Szeredi2020-01-246-22/+23
| | | | | | | | | | | | The ovl_layer struct is never modified except at initialization. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: fix corner case of non-constant st_dev;st_inoAmir Goldstein2020-01-242-17/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On non-samefs overlay without xino, non pure upper inodes should use a pseudo_dev assigned to each unique lower fs, but if lower layer is on the same fs and upper layer, it has no pseudo_dev assigned. In this overlay layers setup: - two filesystems, A and B - upper layer is on A - lower layer 1 is also on A - lower layer 2 is on B Non pure upper overlay inode, whose origin is in layer 1 will have the st_dev;st_ino values of the real lower inode before copy up and the st_dev;st_ino values of the real upper inode after copy up. Fix this inconsitency by assigning a unique pseudo_dev also for upper fs, that will be used as st_dev value along with the lower inode st_dev for overlay inodes in the case above. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: fix corner case of conflicting lower layer uuidAmir Goldstein2020-01-242-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes ovl_lower_uuid_ok() to correctly detect the corner case: - two filesystems, A and B, both have null uuid - upper layer is on A - lower layer 1 is also on A - lower layer 2 is on B In this case, bad_uuid would not have been set for B, because the check only involved the list of lower fs. Hence we'll try to decode a layer 2 origin on layer 1 and fail. We check for conflicting (and null) uuid among all lower layers, including those layers that are on the same fs as the upper layer. Reported-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: generalize the lower_fs[] arrayAmir Goldstein2020-01-243-46/+46
| | | | | | | | | | | | | | | | | | | | | | Rename lower_fs[] array to fs[], extend its size by one and use index fsid (instead of fsid-1) to access the fs[] array. Initialize fs[0] with upper fs values. fsid 0 is reserved even with lower only overlay, so fs[0] remains null in this case. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: simplify ovl_same_sb() helperAmir Goldstein2020-01-246-34/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No code uses the sb returned from this helper, so make it retrun a boolean and rename it to ovl_same_fs(). The xino mode is irrelevant when all layers are on same fs, so instead of describing samefs with mode OVL_XINO_OFF, use a new xino_mode state, which is 0 in the case of samefs, -1 in the case of xino=off and > 0 with xino enabled. Create a new helper ovl_same_dev(), to use instead of the common check for (ovl_same_fs() || xinobits). Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: generalize the lower_layers[] arrayAmir Goldstein2020-01-224-31/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | Rename lower_layers[] array to layers[], extend its size by one and initialize layers[0] with upper layer values. Lower layers are now addressed with index 1..numlower. layers[0] is reserved even with lower only overlay. [SzM: replace ofs->numlower with ofs->numlayer, the latter's value is incremented by one] Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: improving copy-up efficiency for big sparse fileChengguang Xu2020-01-221-2/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Current copy-up is not efficient for big sparse file, It's not only slow but also wasting more disk space when the target lower file has huge hole inside. This patch tries to recognize file hole and skip it during copy-up. Detail logic of hole detection as below: When we detect next data position is larger than current position we will skip that hole, otherwise we copy data in the size of OVL_COPY_UP_CHUNK_SIZE. Actually, it may not recognize all kind of holes and sometimes only skips partial of hole area. However, it will be enough for most of the use cases. Additionally, this optimization relies on lseek(2) SEEK_DATA implementation, so for some specific filesystems which do not support this feature will behave as before on copy-up. Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Chengguang Xu <cgxu519@mykernel.net> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: use ovl_inode_lock in ovl_llseek()Amir Goldstein2020-01-222-2/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In ovl_llseek() we use the overlay inode rwsem to protect against concurrent modifications to real file f_pos, because we copy the overlay file f_pos to/from the real file f_pos. This caused a lockdep warning of locking order violation when the ovl_llseek() operation was called on a lower nested overlay layer while the upper layer fs sb_writers is held (with patch improving copy-up efficiency for big sparse file). Use the internal ovl_inode_lock() instead of the overlay inode rwsem in those cases. It is meant to be used for protecting against concurrent changes to overlay inode internal state changes. The locking order rules are documented to explain this case. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: use pr_fmt auto generate prefixlijiazi2020-01-229-81/+85
| | | | | | | | | | | | | | Use pr_fmt auto generate "overlayfs: " prefix. Signed-off-by: lijiazi <lijiazi@xiaomi.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * ovl: fix wrong WARN_ON() in ovl_cache_update_ino()Amir Goldstein2020-01-221-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The WARN_ON() that child entry is always on overlay st_dev became wrong when we allowed this function to update d_ino in non-samefs setup with xino enabled. It is not true in case of xino bits overflow on a non-dir inode. Leave the WARN_ON() only for directories, where assertion is still true. Fixes: adbf4f7ea834 ("ovl: consistent d_ino for non-samefs with xino") Cc: <stable@vger.kernel.org> # v4.17+ Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | treewide: remove redundant IS_ERR() before error code checkMasahiro Yamada2020-02-044-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'PTR_ERR(p) == -E*' is a stronger condition than IS_ERR(p). Hence, IS_ERR(p) is unneeded. The semantic patch that generates this commit is as follows: // <smpl> @@ expression ptr; constant error_code; @@ -IS_ERR(ptr) && (PTR_ERR(ptr) == - error_code) +PTR_ERR(ptr) == - error_code // </smpl> Link: http://lkml.kernel.org/r/20200106045833.1725-1-masahiroy@kernel.org Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Cc: Julia Lawall <julia.lawall@lip6.fr> Acked-by: Stephen Boyd <sboyd@kernel.org> [drivers/clk/clk.c] Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> [GPIO] Acked-by: Wolfram Sang <wsa@the-dreams.de> [drivers/i2c] Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [acpi/scan.c] Acked-by: Rob Herring <robh@kernel.org> Cc: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | proc: convert everything to "struct proc_ops"Alexey Dobriyan2020-02-0417-144/+143
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in seq_file.h. Conversion rule is: llseek => proc_lseek unlocked_ioctl => proc_ioctl xxx => proc_xxx delete ".owner = THIS_MODULE" line [akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c] [sfr@canb.auug.org.au: fix kernel/sched/psi.c] Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | proc: decouple proc from VFS with "struct proc_ops"Alexey Dobriyan2020-02-046-76/+79
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently core /proc code uses "struct file_operations" for custom hooks, however, VFS doesn't directly call them. Every time VFS expands file_operations hook set, /proc code bloats for no reason. Introduce "struct proc_ops" which contains only those hooks which /proc allows to call into (open, release, read, write, ioctl, mmap, poll). It doesn't contain module pointer as well. Save ~184 bytes per usage: add/remove: 26/26 grow/shrink: 1/4 up/down: 1922/-6674 (-4752) Function old new delta sysvipc_proc_ops - 72 +72 ... config_gz_proc_ops - 72 +72 proc_get_inode 289 339 +50 proc_reg_get_unmapped_area 110 107 -3 close_pdeo 227 224 -3 proc_reg_open 289 284 -5 proc_create_data 60 53 -7 rt_cpu_seq_fops 256 - -256 ... default_affinity_proc_fops 256 - -256 Total: Before=5430095, After=5425343, chg -0.09% Link: http://lkml.kernel.org/r/20191225172228.GA13378@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm: pagewalk: add 'depth' parameter to pte_holeSteven Price2020-02-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The pte_hole() callback is called at multiple levels of the page tables. Code dumping the kernel page tables needs to know what at what depth the missing entry is. Add this is an extra parameter to pte_hole(). When the depth isn't know (e.g. processing a vma) then -1 is passed. The depth that is reported is the actual level where the entry is missing (ignoring any folding that is in place), i.e. any levels where PTRS_PER_P?D is set to 1 are ignored. Note that depth starts at 0 for a PGD so that PUD/PMD/PTE retain their natural numbers as levels 2/3/4. Link: http://lkml.kernel.org/r/20191218162402.45610-16-steven.price@arm.com Signed-off-by: Steven Price <steven.price@arm.com> Tested-by: Zong Li <zong.li@sifive.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Hogan <jhogan@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: "Liang, Kan" <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Burton <paul.burton@mips.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | fs/proc/page.c: allow inspection of last section and fix end detectionDavid Hildenbrand2020-02-041-3/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If max_pfn does not fall onto a section boundary, it is possible to inspect PFNs up to max_pfn, and PFNs above max_pfn, however, max_pfn itself can't be inspected. We can have a valid (and online) memmap at and above max_pfn if max_pfn is not aligned to a section boundary. The whole early section has a memmap and is marked online. Being able to inspect the state of these PFNs is valuable for debugging, especially because max_pfn can change on memory hotplug and expose these memmaps. Also, querying page flags via "./page-types -r -a 0x144001," (tools/vm/page-types.c) inside a x86-64 guest with 4160MB under QEMU results in an (almost) endless loop in user space, because the end is not detected properly when starting after max_pfn. Instead, let's allow to inspect all pages in the highest section and return 0 directly if we try to access pages above that section. While at it, check the count before adjusting it, to avoid masking user errors. Link: http://lkml.kernel.org/r/20191211163201.17179-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Bob Picco <bob.picco@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Steven Sistare <steven.sistare@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | ocfs2: fix oops when writing cloned fileGang He2020-02-041-8/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Writing a cloned file triggers a kernel oops and the user-space command process is also killed by the system. The bug can be reproduced stably via: 1) create a file under ocfs2 file system directory. journalctl -b > aa.txt 2) create a cloned file for this file. reflink aa.txt bb.txt 3) write the cloned file with dd command. dd if=/dev/zero of=bb.txt bs=512 count=1 conv=notrunc The dd command is killed by the kernel, then you can see the oops message via dmesg command. [ 463.875404] BUG: kernel NULL pointer dereference, address: 0000000000000028 [ 463.875413] #PF: supervisor read access in kernel mode [ 463.875416] #PF: error_code(0x0000) - not-present page [ 463.875418] PGD 0 P4D 0 [ 463.875425] Oops: 0000 [#1] SMP PTI [ 463.875431] CPU: 1 PID: 2291 Comm: dd Tainted: G OE 5.3.16-2-default [ 463.875433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 463.875500] RIP: 0010:ocfs2_refcount_cow+0xa4/0x5d0 [ocfs2] [ 463.875505] Code: 06 89 6c 24 38 89 eb f6 44 24 3c 02 74 be 49 8b 47 28 [ 463.875508] RSP: 0018:ffffa2cb409dfce8 EFLAGS: 00010202 [ 463.875512] RAX: ffff8b1ebdca8000 RBX: 0000000000000001 RCX: ffff8b1eb73a9df0 [ 463.875515] RDX: 0000000000056a01 RSI: 0000000000000000 RDI: 0000000000000000 [ 463.875517] RBP: 0000000000000001 R08: ffff8b1eb73a9de0 R09: 0000000000000000 [ 463.875520] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 [ 463.875522] R13: ffff8b1eb922f048 R14: 0000000000000000 R15: ffff8b1eb922f048 [ 463.875526] FS: 00007f8f44d15540(0000) GS:ffff8b1ebeb00000(0000) knlGS:0000000000000000 [ 463.875529] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 463.875532] CR2: 0000000000000028 CR3: 000000003c17a000 CR4: 00000000000006e0 [ 463.875546] Call Trace: [ 463.875596] ? ocfs2_inode_lock_full_nested+0x18b/0x960 [ocfs2] [ 463.875648] ocfs2_file_write_iter+0xaf8/0xc70 [ocfs2] [ 463.875672] new_sync_write+0x12d/0x1d0 [ 463.875688] vfs_write+0xad/0x1a0 [ 463.875697] ksys_write+0xa1/0xe0 [ 463.875710] do_syscall_64+0x60/0x1f0 [ 463.875743] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 463.875758] RIP: 0033:0x7f8f4482ed44 [ 463.875762] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 80 00 00 00 [ 463.875765] RSP: 002b:00007fff300a79d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 463.875769] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8f4482ed44 [ 463.875771] RDX: 0000000000000200 RSI: 000055f771b5c000 RDI: 0000000000000001 [ 463.875774] RBP: 0000000000000200 R08: 00007f8f44af9c78 R09: 0000000000000003 [ 463.875776] R10: 000000000000089f R11: 0000000000000246 R12: 000055f771b5c000 [ 463.875779] R13: 0000000000000200 R14: 0000000000000000 R15: 000055f771b5c000 This regression problem was introduced by commit e74540b28556 ("ocfs2: protect extent tree in ocfs2_prepare_inode_for_write()"). Link: http://lkml.kernel.org/r/20200121050153.13290-1-ghe@suse.com Fixes: e74540b28556 ("ocfs2: protect extent tree in ocfs2_prepare_inode_for_write()"). Signed-off-by: Gang He <ghe@suse.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge tag 'for-5.6-tag' of ↵Linus Torvalds2020-02-0313-83/+193
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull more btrfs updates from David Sterba: "Fixes that arrived after the merge window freeze, mostly stable material. - fix race in tree-mod-log element tracking - fix bio flushing inside extent writepages - fix assertion when in-memory tracking of discarded extents finds an empty tree (eg. after adding a new device) - update logic of temporary read-only block groups to take into account overcommit - fix some fixup worker corner cases: - page could not go through proper COW cycle and the dirty status is lost due to page migration - deadlock if delayed allocation is performed under page lock - fix send emitting invalid clones within the same file - fix statfs reporting 0 free space when global block reserve size is larger than remaining free space but there is still space for new chunks" * tag 'for-5.6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: do not zero f_bavail if we have available space Btrfs: send, fix emission of invalid clone operations within the same file btrfs: do not do delalloc reservation under page lock btrfs: drop the -EBUSY case in __extent_writepage_io Btrfs: keep pages dirty when using btrfs_writepage_fixup_worker btrfs: take overcommit into account in inc_block_group_ro btrfs: fix force usage in inc_block_group_ro btrfs: Correctly handle empty trees in find_first_clear_extent_bit btrfs: flush write bio if we loop in extent_write_cache_pages Btrfs: fix race between adding and putting tree mod seq elements and nodes
| * | btrfs: do not zero f_bavail if we have available spaceJosef Bacik2020-02-021-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There was some logic added a while ago to clear out f_bavail in statfs() if we did not have enough free metadata space to satisfy our global reserve. This was incorrect at the time, however didn't really pose a problem for normal file systems because we would often allocate chunks if we got this low on free metadata space, and thus wouldn't really hit this case unless we were actually full. Fast forward to today and now we are much better about not allocating metadata chunks all of the time. Couple this with d792b0f19711 ("btrfs: always reserve our entire size for the global reserve") which now means we'll easily have a larger global reserve than our free space, we are now more likely to trip over this while still having plenty of space. Fix this by skipping this logic if the global rsv's space_info is not full. space_info->full is 0 unless we've attempted to allocate a chunk for that space_info and that has failed. If this happens then the space for the global reserve is definitely sacred and we need to report b_avail == 0, but before then we can just use our calculated b_avail. Reported-by: Martin Steigerwald <martin@lichtvoll.de> Fixes: ca8a51b3a979 ("btrfs: statfs: report zero available if metadata are exhausted") CC: stable@vger.kernel.org # 4.5+ Reviewed-by: Qu Wenruo <wqu@suse.com> Tested-By: Martin Steigerwald <martin@lichtvoll.de> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | Btrfs: send, fix emission of invalid clone operations within the same fileFilipe Manana2020-01-311-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When doing an incremental send and a file has extents shared with itself at different file offsets, it's possible for send to emit clone operations that will fail at the destination because the source range goes beyond the file's current size. This happens when the file size has increased in the send snapshot, there is a hole between the shared extents and both shared extents are at file offsets which are greater the file's size in the parent snapshot. Example: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt/sdb $ xfs_io -f -c "pwrite -S 0xf1 0 64K" /mnt/sdb/foobar $ btrfs subvolume snapshot -r /mnt/sdb /mnt/sdb/base $ btrfs send -f /tmp/1.snap /mnt/sdb/base # Create a 320K extent at file offset 512K. $ xfs_io -c "pwrite -S 0xab 512K 64K" /mnt/sdb/foobar $ xfs_io -c "pwrite -S 0xcd 576K 64K" /mnt/sdb/foobar $ xfs_io -c "pwrite -S 0xef 640K 64K" /mnt/sdb/foobar $ xfs_io -c "pwrite -S 0x64 704K 64K" /mnt/sdb/foobar $ xfs_io -c "pwrite -S 0x73 768K 64K" /mnt/sdb/foobar # Clone part of that 320K extent into a lower file offset (192K). # This file offset is greater than the file's size in the parent # snapshot (64K). Also the clone range is a bit behind the offset of # the 320K extent so that we leave a hole between the shared extents. $ xfs_io -c "reflink /mnt/sdb/foobar 448K 192K 192K" /mnt/sdb/foobar $ btrfs subvolume snapshot -r /mnt/sdb /mnt/sdb/incr $ btrfs send -p /mnt/sdb/base -f /tmp/2.snap /mnt/sdb/incr $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt/sdc $ btrfs receive -f /tmp/1.snap /mnt/sdc $ btrfs receive -f /tmp/2.snap /mnt/sdc ERROR: failed to clone extents to foobar: Invalid argument The problem is that after processing the extent at file offset 256K, which refers to the first 128K of the 320K extent created by the buffered write operations, we have 'cur_inode_next_write_offset' set to 384K, which corresponds to the end offset of the partially shared extent (256K + 128K) and to the current file size in the receiver. Then when we process the extent at offset 512K, we do extent backreference iteration to figure out if we can clone the extent from some other inode or from the same inode, and we consider the extent at offset 256K of the same inode as a valid source for a clone operation, which is not correct because at that point the current file size in the receiver is 384K, which corresponds to the end of last processed extent (at file offset 256K), so using a clone source range from 256K to 256K + 320K is invalid because that goes past the current size of the file (384K) - this makes the receiver get an -EINVAL error when attempting the clone operation. So fix this by excluding clone sources that have a range that goes beyond the current file size in the receiver when iterating extent backreferences. A test case for fstests follows soon. Fixes: 11f2069c113e02 ("Btrfs: send, allow clone operations within the same file") CC: stable@vger.kernel.org # 5.5+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | btrfs: do not do delalloc reservation under page lockJosef Bacik2020-01-311-16/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We ran into a deadlock in production with the fixup worker. The stack traces were as follows: Thread responsible for the writeout, waiting on the page lock [<0>] io_schedule+0x12/0x40 [<0>] __lock_page+0x109/0x1e0 [<0>] extent_write_cache_pages+0x206/0x360 [<0>] extent_writepages+0x40/0x60 [<0>] do_writepages+0x31/0xb0 [<0>] __writeback_single_inode+0x3d/0x350 [<0>] writeback_sb_inodes+0x19d/0x3c0 [<0>] __writeback_inodes_wb+0x5d/0xb0 [<0>] wb_writeback+0x231/0x2c0 [<0>] wb_workfn+0x308/0x3c0 [<0>] process_one_work+0x1e0/0x390 [<0>] worker_thread+0x2b/0x3c0 [<0>] kthread+0x113/0x130 [<0>] ret_from_fork+0x35/0x40 [<0>] 0xffffffffffffffff Thread of the fixup worker who is holding the page lock [<0>] start_delalloc_inodes+0x241/0x2d0 [<0>] btrfs_start_delalloc_roots+0x179/0x230 [<0>] btrfs_alloc_data_chunk_ondemand+0x11b/0x2e0 [<0>] btrfs_check_data_free_space+0x53/0xa0 [<0>] btrfs_delalloc_reserve_space+0x20/0x70 [<0>] btrfs_writepage_fixup_worker+0x1fc/0x2a0 [<0>] normal_work_helper+0x11c/0x360 [<0>] process_one_work+0x1e0/0x390 [<0>] worker_thread+0x2b/0x3c0 [<0>] kthread+0x113/0x130 [<0>] ret_from_fork+0x35/0x40 [<0>] 0xffffffffffffffff Thankfully the stars have to align just right to hit this. First you have to end up in the fixup worker, which is tricky by itself (my reproducer does DIO reads into a MMAP'ed region, so not a common operation). Then you have to have less than a page size of free data space and 0 unallocated space so you go down the "commit the transaction to free up pinned space" path. This was accomplished by a random balance that was running on the host. Then you get this deadlock. I'm still in the process of trying to force the deadlock to happen on demand, but I've hit other issues. I can still trigger the fixup worker path itself so this patch has been tested in that regard, so the normal case is fine. Fixes: 87826df0ec36 ("btrfs: delalloc for page dirtied out-of-band in fixup worker") Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | btrfs: drop the -EBUSY case in __extent_writepage_ioJosef Bacik2020-01-311-5/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | Now that we only return 0 or -EAGAIN from btrfs_writepage_cow_fixup, we do not need this -EBUSY case. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | Btrfs: keep pages dirty when using btrfs_writepage_fixup_workerChris Mason2020-01-311-17/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For COW, btrfs expects pages dirty pages to have been through a few setup steps. This includes reserving space for the new block allocations and marking the range in the state tree for delayed allocation. A few places outside btrfs will dirty pages directly, especially when unmapping mmap'd pages. In order for these to properly go through COW, we run them through a fixup worker to wait for stable pages, and do the delalloc prep. 87826df0ec36 added a window where the dirty pages were cleaned, but pending more action from the fixup worker. We clear_page_dirty_for_io() before we call into writepage, so the page is no longer dirty. The commit changed it so now we leave the page clean between unlocking it here and the fixup worker starting at some point in the future. During this window, page migration can jump in and relocate the page. Once our fixup work actually starts, it finds page->mapping is NULL and we end up freeing the page without ever writing it. This leads to crc errors and other exciting problems, since it screws up the whole statemachine for waiting for ordered extents. The fix here is to keep the page dirty while we're waiting for the fixup worker to get to work. This is accomplished by returning -EAGAIN from btrfs_writepage_cow_fixup if we queued the page up for fixup, which will cause the writepage function to redirty the page. Because we now expect the page to be dirty once it gets to the fixup worker we must adjust the error cases to call clear_page_dirty_for_io() on the page. That is the bulk of the patch, but it is not the fix, the fix is the -EAGAIN from btrfs_writepage_cow_fixup. We cannot separate these two changes out because the error conditions change with the new expectations. Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | btrfs: take overcommit into account in inc_block_group_roJosef Bacik2020-01-313-19/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | inc_block_group_ro does a calculation to see if we have enough room left over if we mark this block group as read only in order to see if it's ok to mark the block group as read only. The problem is this calculation _only_ works for data, where our used is always less than our total. For metadata we will overcommit, so this will almost always fail for metadata. Fix this by exporting btrfs_can_overcommit, and then see if we have enough space to remove the remaining free space in the block group we are trying to mark read only. If we do then we can mark this block group as read only. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | btrfs: fix force usage in inc_block_group_roJosef Bacik2020-01-311-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For some reason we've translated the do_chunk_alloc that goes into btrfs_inc_block_group_ro to force in inc_block_group_ro, but these are two different things. force for inc_block_group_ro is used when we are forcing the block group read only no matter what, for example when the underlying chunk is marked read only. We need to not do the space check here as this block group needs to be read only. btrfs_inc_block_group_ro() has a do_chunk_alloc flag that indicates that we need to pre-allocate a chunk before marking the block group read only. This has nothing to do with forcing, and in fact we _always_ want to do the space check in this case, so unconditionally pass false for force in this case. Then fixup inc_block_group_ro to honor force as it's expected and documented to do. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | btrfs: Correctly handle empty trees in find_first_clear_extent_bitNikolay Borisov2020-01-312-14/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Raviu reported that running his regular fs_trim segfaulted with the following backtrace: [ 237.525947] assertion failed: prev, in ../fs/btrfs/extent_io.c:1595 [ 237.525984] ------------[ cut here ]------------ [ 237.525985] kernel BUG at ../fs/btrfs/ctree.h:3117! [ 237.525992] invalid opcode: 0000 [#1] SMP PTI [ 237.525998] CPU: 4 PID: 4423 Comm: fstrim Tainted: G U OE 5.4.14-8-vanilla #1 [ 237.526001] Hardware name: ASUSTeK COMPUTER INC. [ 237.526044] RIP: 0010:assfail.constprop.58+0x18/0x1a [btrfs] [ 237.526079] Call Trace: [ 237.526120] find_first_clear_extent_bit+0x13d/0x150 [btrfs] [ 237.526148] btrfs_trim_fs+0x211/0x3f0 [btrfs] [ 237.526184] btrfs_ioctl_fitrim+0x103/0x170 [btrfs] [ 237.526219] btrfs_ioctl+0x129a/0x2ed0 [btrfs] [ 237.526227] ? filemap_map_pages+0x190/0x3d0 [ 237.526232] ? do_filp_open+0xaf/0x110 [ 237.526238] ? _copy_to_user+0x22/0x30 [ 237.526242] ? cp_new_stat+0x150/0x180 [ 237.526247] ? do_vfs_ioctl+0xa4/0x640 [ 237.526278] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [ 237.526283] do_vfs_ioctl+0xa4/0x640 [ 237.526288] ? __do_sys_newfstat+0x3c/0x60 [ 237.526292] ksys_ioctl+0x70/0x80 [ 237.526297] __x64_sys_ioctl+0x16/0x20 [ 237.526303] do_syscall_64+0x5a/0x1c0 [ 237.526310] entry_SYSCALL_64_after_hwframe+0x49/0xbe That was due to btrfs_fs_device::aloc_tree being empty. Initially I thought this wasn't possible and as a percaution have put the assert in find_first_clear_extent_bit. Turns out this is indeed possible and could happen when a file system with SINGLE data/metadata profile has a 2nd device added. Until balance is run or a new chunk is allocated on this device it will be completely empty. In this case find_first_clear_extent_bit should return the full range [0, -1ULL] and let the caller handle this i.e for trim the end will be capped at the size of actual device. Link: https://lore.kernel.org/linux-btrfs/izW2WNyvy1dEDweBICizKnd2KDwDiDyY2EYQr4YCwk7pkuIpthx-JRn65MPBde00ND6V0_Lh8mW0kZwzDiLDv25pUYWxkskWNJnVP0kgdMA=@protonmail.com/ Fixes: 45bfcfc168f8 ("btrfs: Implement find_first_clear_extent_bit") CC: stable@vger.kernel.org # 5.2+ Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | btrfs: flush write bio if we loop in extent_write_cache_pagesJosef Bacik2020-01-311-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There exists a deadlock with range_cyclic that has existed forever. If we loop around with a bio already built we could deadlock with a writer who has the page locked that we're attempting to write but is waiting on a page in our bio to be written out. The task traces are as follows PID: 1329874 TASK: ffff889ebcdf3800 CPU: 33 COMMAND: "kworker/u113:5" #0 [ffffc900297bb658] __schedule at ffffffff81a4c33f #1 [ffffc900297bb6e0] schedule at ffffffff81a4c6e3 #2 [ffffc900297bb6f8] io_schedule at ffffffff81a4ca42 #3 [ffffc900297bb708] __lock_page at ffffffff811f145b #4 [ffffc900297bb798] __process_pages_contig at ffffffff814bc502 #5 [ffffc900297bb8c8] lock_delalloc_pages at ffffffff814bc684 #6 [ffffc900297bb900] find_lock_delalloc_range at ffffffff814be9ff #7 [ffffc900297bb9a0] writepage_delalloc at ffffffff814bebd0 #8 [ffffc900297bba18] __extent_writepage at ffffffff814bfbf2 #9 [ffffc900297bba98] extent_write_cache_pages at ffffffff814bffbd PID: 2167901 TASK: ffff889dc6a59c00 CPU: 14 COMMAND: "aio-dio-invalid" #0 [ffffc9003b50bb18] __schedule at ffffffff81a4c33f #1 [ffffc9003b50bba0] schedule at ffffffff81a4c6e3 #2 [ffffc9003b50bbb8] io_schedule at ffffffff81a4ca42 #3 [ffffc9003b50bbc8] wait_on_page_bit at ffffffff811f24d6 #4 [ffffc9003b50bc60] prepare_pages at ffffffff814b05a7 #5 [ffffc9003b50bcd8] btrfs_buffered_write at ffffffff814b1359 #6 [ffffc9003b50bdb0] btrfs_file_write_iter at ffffffff814b5933 #7 [ffffc9003b50be38] new_sync_write at ffffffff8128f6a8 #8 [ffffc9003b50bec8] vfs_write at ffffffff81292b9d #9 [ffffc9003b50bf00] ksys_pwrite64 at ffffffff81293032 I used drgn to find the respective pages we were stuck on page_entry.page 0xffffea00fbfc7500 index 8148 bit 15 pid 2167901 page_entry.page 0xffffea00f9bb7400 index 7680 bit 0 pid 1329874 As you can see the kworker is waiting for bit 0 (PG_locked) on index 7680, and aio-dio-invalid is waiting for bit 15 (PG_writeback) on index 8148. aio-dio-invalid has 7680, and the kworker epd looks like the following crash> struct extent_page_data ffffc900297bbbb0 struct extent_page_data { bio = 0xffff889f747ed830, tree = 0xffff889eed6ba448, extent_locked = 0, sync_io = 0 } Probably worth mentioning as well that it waits for writeback of the page to complete while holding a lock on it (at prepare_pages()). Using drgn I walked the bio pages looking for page 0xffffea00fbfc7500 which is the one we're waiting for writeback on bio = Object(prog, 'struct bio', address=0xffff889f747ed830) for i in range(0, bio.bi_vcnt.value_()): bv = bio.bi_io_vec[i] if bv.bv_page.value_() == 0xffffea00fbfc7500: print("FOUND IT") which validated what I suspected. The fix for this is simple, flush the epd before we loop back around to the beginning of the file during writeout. Fixes: b293f02e1423 ("Btrfs: Add writepages support") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | Btrfs: fix race between adding and putting tree mod seq elements and nodesFilipe Manana2020-01-315-16/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a race between adding and removing elements to the tree mod log list and rbtree that can lead to use-after-free problems. Consider the following example that explains how/why the problems happens: 1) Task A has mod log element with sequence number 200. It currently is the only element in the mod log list; 2) Task A calls btrfs_put_tree_mod_seq() because it no longer needs to access the tree mod log. When it enters the function, it initializes 'min_seq' to (u64)-1. Then it acquires the lock 'tree_mod_seq_lock' before checking if there are other elements in the mod seq list. Since the list it empty, 'min_seq' remains set to (u64)-1. Then it unlocks the lock 'tree_mod_seq_lock'; 3) Before task A acquires the lock 'tree_mod_log_lock', task B adds itself to the mod seq list through btrfs_get_tree_mod_seq() and gets a sequence number of 201; 4) Some other task, name it task C, modifies a btree and because there elements in the mod seq list, it adds a tree mod elem to the tree mod log rbtree. That node added to the mod log rbtree is assigned a sequence number of 202; 5) Task B, which is doing fiemap and resolving indirect back references, calls btrfs get_old_root(), with 'time_seq' == 201, which in turn calls tree_mod_log_search() - the search returns the mod log node from the rbtree with sequence number 202, created by task C; 6) Task A now acquires the lock 'tree_mod_log_lock', starts iterating the mod log rbtree and finds the node with sequence number 202. Since 202 is less than the previously computed 'min_seq', (u64)-1, it removes the node and frees it; 7) Task B still has a pointer to the node with sequence number 202, and it dereferences the pointer itself and through the call to __tree_mod_log_rewind(), resulting in a use-after-free problem. This issue can be triggered sporadically with the test case generic/561 from fstests, and it happens more frequently with a higher number of duperemove processes. When it happens to me, it either freezes the VM or it produces a trace like the following before crashing: [ 1245.321140] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI [ 1245.321200] CPU: 1 PID: 26997 Comm: pool Not tainted 5.5.0-rc6-btrfs-next-52 #1 [ 1245.321235] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014 [ 1245.321287] RIP: 0010:rb_next+0x16/0x50 [ 1245.321307] Code: .... [ 1245.321372] RSP: 0018:ffffa151c4d039b0 EFLAGS: 00010202 [ 1245.321388] RAX: 6b6b6b6b6b6b6b6b RBX: ffff8ae221363c80 RCX: 6b6b6b6b6b6b6b6b [ 1245.321409] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff8ae221363c80 [ 1245.321439] RBP: ffff8ae20fcc4688 R08: 0000000000000002 R09: 0000000000000000 [ 1245.321475] R10: ffff8ae20b120910 R11: 00000000243f8bb1 R12: 0000000000000038 [ 1245.321506] R13: ffff8ae221363c80 R14: 000000000000075f R15: ffff8ae223f762b8 [ 1245.321539] FS: 00007fdee1ec7700(0000) GS:ffff8ae236c80000(0000) knlGS:0000000000000000 [ 1245.321591] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1245.321614] CR2: 00007fded4030c48 CR3: 000000021da16003 CR4: 00000000003606e0 [ 1245.321642] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1245.321668] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1245.321706] Call Trace: [ 1245.321798] __tree_mod_log_rewind+0xbf/0x280 [btrfs] [ 1245.321841] btrfs_search_old_slot+0x105/0xd00 [btrfs] [ 1245.321877] resolve_indirect_refs+0x1eb/0xc60 [btrfs] [ 1245.321912] find_parent_nodes+0x3dc/0x11b0 [btrfs] [ 1245.321947] btrfs_check_shared+0x115/0x1c0 [btrfs] [ 1245.321980] ? extent_fiemap+0x59d/0x6d0 [btrfs] [ 1245.322029] extent_fiemap+0x59d/0x6d0 [btrfs] [ 1245.322066] do_vfs_ioctl+0x45a/0x750 [ 1245.322081] ksys_ioctl+0x70/0x80 [ 1245.322092] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 1245.322113] __x64_sys_ioctl+0x16/0x20 [ 1245.322126] do_syscall_64+0x5c/0x280 [ 1245.322139] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 1245.322155] RIP: 0033:0x7fdee3942dd7 [ 1245.322177] Code: .... [ 1245.322258] RSP: 002b:00007fdee1ec6c88 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 1245.322294] RAX: ffffffffffffffda RBX: 00007fded40210d8 RCX: 00007fdee3942dd7 [ 1245.322314] RDX: 00007fded40210d8 RSI: 00000000c020660b RDI: 0000000000000004 [ 1245.322337] RBP: 0000562aa89e7510 R08: 0000000000000000 R09: 00007fdee1ec6d44 [ 1245.322369] R10: 0000000000000073 R11: 0000000000000246 R12: 00007fdee1ec6d48 [ 1245.322390] R13: 00007fdee1ec6d40 R14: 00007fded40210d0 R15: 00007fdee1ec6d50 [ 1245.322423] Modules linked in: .... [ 1245.323443] ---[ end trace 01de1e9ec5dff3cd ]--- Fix this by ensuring that btrfs_put_tree_mod_seq() computes the minimum sequence number and iterates the rbtree while holding the lock 'tree_mod_log_lock' in write mode. Also get rid of the 'tree_mod_seq_lock' lock, since it is now redundant. Fixes: bd989ba359f2ac ("Btrfs: add tree modification log functions") Fixes: 097b8a7c9e48e2 ("Btrfs: join tree mod log code with the code holding back delayed refs") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | | Merge tag '5.6-rc-small-smb3-fix-for-stable' of ↵Linus Torvalds2020-02-012-2/+2
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.samba.org/sfrench/cifs-2.6 Pull cifs fix from Steve French: "Small SMB3 fix for stable (fixes problem with soft mounts)" * tag '5.6-rc-small-smb3-fix-for-stable' of git://git.samba.org/sfrench/cifs-2.6: cifs: update internal module version number cifs: fix soft mounts hanging in the reconnect code
| * | | cifs: update internal module version numberSteve French2020-01-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | To 2.25 Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | cifs: fix soft mounts hanging in the reconnect codeRonnie Sahlberg2020-01-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | RHBZ: 1795429 In recent DFS updates we have a new variable controlling how many times we will retry to reconnect the share. If DFS is not used, then this variable is initialized to 0 in: static inline int dfs_cache_get_nr_tgts(const struct dfs_cache_tgt_list *tl) { return tl ? tl->tl_numtgts : 0; } This means that in the reconnect loop in smb2_reconnect() we will immediately wrap retries to -1 and never actually get to pass this conditional: if (--retries) continue; The effect is that we no longer reach the point where we fail the commands with -EHOSTDOWN and basically the kernel threads are virtually hung and unkillable. Fixes: a3a53b7603798fd8 (cifs: Add support for failover in smb2_reconnect()) Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> CC: Stable <stable@vger.kernel.org>
* | | | vfs: fix do_last() regressionAl Viro2020-02-011-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Brown paperbag time: fetching ->i_uid/->i_mode really should've been done from nd->inode. I even suggested that, but the reason for that has slipped through the cracks and I went for dir->d_inode instead - made for more "obvious" patch. Analysis: - at the entry into do_last() and all the way to step_into(): dir (aka nd->path.dentry) is known not to have been freed; so's nd->inode and it's equal to dir->d_inode unless we are already doomed to -ECHILD. inode of the file to get opened is not known. - after step_into(): inode of the file to get opened is known; dir might be pointing to freed memory/be negative/etc. - at the call of may_create_in_sticky(): guaranteed to be out of RCU mode; inode of the file to get opened is known and pinned; dir might be garbage. The last was the reason for the original patch. Except that at the do_last() entry we can be in RCU mode and it is possible that nd->path.dentry->d_inode has already changed under us. In that case we are going to fail with -ECHILD, but we need to be careful; nd->inode is pointing to valid struct inode and it's the same as nd->path.dentry->d_inode in "won't fail with -ECHILD" case, so we should use that. Reported-by: "Rantala, Tommi T. (Nokia - FI/Espoo)" <tommi.t.rantala@nokia.com> Reported-by: syzbot+190005201ced78a74ad6@syzkaller.appspotmail.com Wearing-brown-paperbag: Al Viro <viro@zeniv.linux.org.uk> Cc: stable@kernel.org Fixes: d0cb50185ae9 ("do_last(): fetch directory ->i_mode and ->i_uid before it's too late") Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | Merge tag 'gfs2-for-5.6' of ↵Linus Torvalds2020-01-3112-70/+73
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2 Pull gfs2 updates from Andreas Gruenbacher: - Fix some corner cases on filesystems with a block size < page size. - Fix a corner case that could expose incorrect access times over nfs. - Revert an otherwise sensible revoke accounting cleanup that causes assertion failures. The revoke accounting is whacky and needs to be fixed properly before we can add back this cleanup. - Various other minor cleanups. In addition, please expect to see another pull request from Bob Peterson about his gfs2 recovery patch queue shortly. * tag 'gfs2-for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: Revert "gfs2: eliminate tr_num_revoke_rm" gfs2: remove unused LBIT macros fs/gfs2: remove unused IS_DINODE and IS_LEAF macros gfs2: Remove GFS2_MIN_LVB_SIZE define gfs2: Fix incorrect variable name gfs2: Avoid access time thrashing in gfs2_inode_lookup gfs2: minor cleanup: remove unneeded variable ret in gfs2_jdata_writepage gfs2: eliminate ssize parameter from gfs2_struct2blk gfs2: Another gfs2_find_jhead fix
| * | | | Revert "gfs2: eliminate tr_num_revoke_rm"Bob Peterson2020-01-283-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit e955537e3262de8e56f070b13817f525f472fa00. Before patch e955537e32, tr_num_revoke tracked the number of revokes added to the transaction, and tr_num_revoke_rm tracked how many revokes were removed. But since revokes are queued off the sdp (superblock) pointer, some transactions could remove more revokes than they added. (e.g. revokes added by a different process). Commit e955537e32 eliminated transaction variable tr_num_revoke_rm, but in order to do so, it changed the accounting to always use tr_num_revoke for its math. Since you can remove more revokes than you add, tr_num_revoke could now become a negative value. This negative value broke the assert in function gfs2_trans_end: if (gfs2_assert_withdraw(sdp, (nbuf <=3D tr->tr_blocks) && (tr->tr_num_revoke <=3D tr->tr_revokes))) One way to fix this is to simply remove the tr_num_revoke clause from the assert and allow the value to become negative. Andreas didn't like that idea, so instead, we decided to revert e955537e32. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * | | | gfs2: remove unused LBIT macrosAlex Shi2020-01-211-10/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 223b2b889f37 ("GFS2: Fix alignment issue and tidy gfs2_bitfit"), these 3 macros aren't used anymore, so remove them. Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * | | | fs/gfs2: remove unused IS_DINODE and IS_LEAF macrosAlex Shi2020-01-211-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 1579343a73e3 ("GFS2: Remove dirent_first() function"), these macros aren't used any more, so remove them. Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * | | | gfs2: Remove GFS2_MIN_LVB_SIZE defineAndreas Gruenbacher2020-01-202-3/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The dlm lockspace is set up to have lock value blocks of GDLM_LVB_SIZE bytes, and dlm is the only lock manager we support, so there is no point in claiming that the lock value block could have any other size. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * | | | gfs2: Fix incorrect variable nameAndreas Gruenbacher2020-01-202-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename sd_log_commited_revoke to sd_log_committed_revoke. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * | | | gfs2: Avoid access time thrashing in gfs2_inode_lookupAndreas Gruenbacher2020-01-151-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In gfs2_inode_lookup, we initialize inode->i_atime to the lowest possibly value after gfs2_inode_refresh may already have been called. This should be the other way around, but we didn't notice because usually the inode type is known from the directory entry and so gfs2_inode_lookup won't call gfs2_inode_refresh. In addition, only initialize ip->i_no_formal_ino from no_formal_ino when actually needed. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * | | | gfs2: minor cleanup: remove unneeded variable ret in gfs2_jdata_writepageBob Peterson2020-01-081-3/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch simply removes variable ret, which is used to store the return code of its call to __gfs2_jdata_writepage, in favor of just returning the result directly. Signed-off-by: Bob Peterson <rpeterso@redhat.com>
| * | | | gfs2: eliminate ssize parameter from gfs2_struct2blkBob Peterson2020-01-077-14/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Every caller of function gfs2_struct2blk specified sizeof(u64). This patch eliminates the unnecessary parameter and replaces the size calculation with a new superblock variable that is computed to be the maximum number of block pointers we can fit inside a log descriptor, as is done for pointers per dinode and indirect block. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Reviewed-by: Andrew Price <anprice@redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
| * | | | gfs2: Another gfs2_find_jhead fixAndreas Gruenbacher2020-01-071-24/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On filesystems with a block size smaller than the page size, gfs2_find_jhead can split a page across two bios (for example, when blocks are not allocated consecutively). When that happens, the first bio that completes will unlock the page in its bi_end_io handler even though the page hasn't been read completely yet. Fix that by using a chained bio for the rest of the page. While at it, clean up the sector calculation logic in gfs2_log_alloc_bio. In gfs2_find_jhead, simplify the disk block and offset calculation logic and fix a variable name. Fixes: f4686c26ecc3 ("gfs2: read journal in large chunks") Cc: stable@vger.kernel.org # v5.2+ Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
* | | | | Merge tag 'iomap-5.6-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds2020-01-311-13/+5
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull iomap fix from Darrick Wong: "A single patch fixing an off-by-one error when we're checking to see how far we're gotten into an EOF page" * tag 'iomap-5.6-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: fs: Fix page_mkwrite off-by-one errors
| * | | | | fs: Fix page_mkwrite off-by-one errorsAndreas Gruenbacher2020-01-061-13/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The check in block_page_mkwrite that is meant to determine whether an offset is within the inode size is off by one. This bug has been copied into iomap_page_mkwrite and several filesystems (ubifs, ext4, f2fs, ceph). Fix that by introducing a new page_mkwrite_check_truncate helper that checks for truncate and computes the bytes in the page up to EOF. Use the helper in iomap. NOTE from Darrick: The original patch fixed a number of filesystems, but then there were merge conflicts with the f2fs for-next tree; a subsequent re-submission of the patch had different btrfs changes with no explanation; and Christoph complained that each per-fs fix should be a separate patch. In my view that's too much risk to take on, so I decided to drop all the hunks except for iomap, since I've actually QA'd XFS. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> [darrick: drop everything but the iomap parts] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
* | | | | | Merge branch 'akpm' (patches from Andrew)Linus Torvalds2020-01-3125-170/+236
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull updates from Andrew Morton: "Most of -mm and quite a number of other subsystems: hotfixes, scripts, ocfs2, misc, lib, binfmt, init, reiserfs, exec, dma-mapping, kcov. MM is fairly quiet this time. Holidays, I assume" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits) kcov: ignore fault-inject and stacktrace include/linux/io-mapping.h-mapping: use PHYS_PFN() macro in io_mapping_map_atomic_wc() execve: warn if process starts with executable stack reiserfs: prevent NULL pointer dereference in reiserfs_insert_item() init/main.c: fix misleading "This architecture does not have kernel memory protection" message init/main.c: fix quoted value handling in unknown_bootoption init/main.c: remove unnecessary repair_env_string in do_initcall_level init/main.c: log arguments and environment passed to init fs/binfmt_elf.c: coredump: allow process with empty address space to coredump fs/binfmt_elf.c: coredump: delete duplicated overflow check fs/binfmt_elf.c: coredump: allocate core ELF header on stack fs/binfmt_elf.c: make BAD_ADDR() unlikely fs/binfmt_elf.c: better codegen around current->mm fs/binfmt_elf.c: don't copy ELF header around fs/binfmt_elf.c: fix ->start_code calculation fs/binfmt_elf.c: smaller code generation around auxv vector fill lib/find_bit.c: uninline helper _find_next_bit() lib/find_bit.c: join _find_next_bit{_le} uapi: rename ext2_swab() to swab() and share globally in swab.h lib/scatterlist.c: adjust indentation in __sg_alloc_table ...
| * | | | | | execve: warn if process starts with executable stackAlexey Dobriyan2020-01-311-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There were few episodes of silent downgrade to an executable stack over years: 1) linking innocent looking assembly file will silently add executable stack if proper linker options is not given as well: $ cat f.S .intel_syntax noprefix .text .globl f f: ret $ cat main.c void f(void); int main(void) { f(); return 0; } $ gcc main.c f.S $ readelf -l ./a.out GNU_STACK 0x0000000000000000 0x0000000000000000 0x0000000000000000 0x0000000000000000 0x0000000000000000 RWE 0x10 ^^^ 2) converting C99 nested function into a closure https://nullprogram.com/blog/2019/11/15/ void intsort2(int *base, size_t nmemb, _Bool invert) { int cmp(const void *a, const void *b) { int r = *(int *)a - *(int *)b; return invert ? -r : r; } qsort(base, nmemb, sizeof(*base), cmp); } will silently require stack trampolines while non-closure version will not. Without doubt this behaviour is documented somewhere, add a warning so that developers and users can at least notice. After so many years of x86_64 having proper executable stack support it should not cause too many problems. Link: http://lkml.kernel.org/r/20191208171918.GC19716@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Will Deacon <will@kernel.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-08 20:27:40 +0000