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Pull ext4 fixes from Ted Ts'o:
"Regression and bug fixes:
- Performance regression fix from 5.18 on a Rasberry Pi
- Fix extent parsing bug which triggers a BUG_ON when a (corrupted)
extent tree has has a non-root node when zero entries.
- Fix a livelock where in the right (wrong) circumstances a large
number of nfsd threads can try to write to a nearly full file
system, and retry for hours(!)"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: limit the number of retries after discarding preallocations blocks
ext4: fix bug in extents parsing when eh_entries == 0 and eh_depth > 0
ext4: use buckets for cr 1 block scan instead of rbtree
ext4: use locality group preallocation for small closed files
ext4: make directory inode spreading reflect flexbg size
ext4: avoid unnecessary spreading of allocations among groups
ext4: make mballoc try target group first even with mb_optimize_scan
Pull NVDIMM and DAX fixes from Dan Williams:
"A recently discovered one-line fix for devdax that further addresses a
v5.5 regression, and (a bit embarrassing) a small batch of fixes that
have been sitting in my fixes tree for weeks.
The older fixes have soaked in linux-next during that time and address
an fsdax infinite loop and some other minor fixups.
- Fix a infinite loop bug in fsdax
- Fix memory-type detection for devdax (EINJ regression)
- Small cleanups"
* tag 'dax-and-nvdimm-fixes-v6.0-final' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
devdax: Fix soft-reservation memory description
fsdax: Fix infinite loop in dax_iomap_rw()
nvdimm/namespace: drop nested variable in create_namespace_pmem()
ndtest: Cleanup all of blk namespace specific code
pmem: fix a name collision
This patch avoids threads live-locking for hours when a large number
threads are competing over the last few free extents as they blocks
getting added and removed from preallocation pools. From our bug
reporter:
A reliable way for triggering this has multiple writers
continuously write() to files when the filesystem is full, while
small amounts of space are freed (e.g. by truncating a large file
-1MiB at a time). In the local filesystem, this can be done by
simply not checking the return code of write (0) and/or the error
(ENOSPACE) that is set. Over NFS with an async mount, even clients
with proper error checking will behave this way since the linux NFS
client implementation will not propagate the server errors [the
write syscalls immediately return success] until the file handle is
closed. This leads to a situation where NFS clients send a
continuous stream of WRITE rpcs which result in ERRNOSPACE -- but
since the client isn't seeing this, the stream of writes continues
at maximum network speed.
When some space does appear, multiple writers will all attempt to
claim it for their current write. For NFS, we may see dozens to
hundreds of threads that do this.
The real-world scenario of this is database backup tooling (in
particular, github.com/mdkent/percona-xtrabackup) which may write
large files (>1TiB) to NFS for safe keeping. Some temporary files
are written, rewound, and read back -- all before closing the file
handle (the temp file is actually unlinked, to trigger automatic
deletion on close/crash.) An application like this operating on an
async NFS mount will not see an error code until TiB have been
written/read.
The lockup was observed when running this database backup on large
filesystems (64 TiB in this case) with a high number of block
groups and no free space. Fragmentation is generally not a factor
in this filesystem (~thousands of large files, mostly contiguous
except for the parts written while the filesystem is at capacity.)
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Pull i2c fixes from Wolfram Sang:
"I2C driver bugfixes for mlxbf and imx, a few documentation fixes after
the rework this cycle, and one hardening for the i2c-mux core"
* tag 'i2c-for-6.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: mux: harden i2c_mux_alloc() against integer overflows
i2c: mlxbf: Fix frequency calculation
i2c: mlxbf: prevent stack overflow in mlxbf_i2c_smbus_start_transaction()
i2c: mlxbf: incorrect base address passed during io write
Documentation: i2c: fix references to other documents
MAINTAINERS: remove Nehal Shah from AMD MP2 I2C DRIVER
i2c: imx: If pm_runtime_get_sync() returned 1 device access is possible
Pick up another "Soft Reservation" fix for v6.0-final on top of some
straggling nvdimm fixes that missed v5.19.
When walking through an inode extents, the ext4_ext_binsearch_idx() function
assumes that the extent header has been previously validated. However, there
are no checks that verify that the number of entries (eh->eh_entries) is
non-zero when depth is > 0. And this will lead to problems because the
EXT_FIRST_INDEX() and EXT_LAST_INDEX() will return garbage and result in this:
[ 135.245946] ------------[ cut here ]------------
[ 135.247579] kernel BUG at fs/ext4/extents.c:2258!
[ 135.249045] invalid opcode: 0000 [#1] PREEMPT SMP
[ 135.250320] CPU: 2 PID: 238 Comm: tmp118 Not tainted 5.19.0-rc8+ #4
[ 135.252067] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014
[ 135.255065] RIP: 0010:ext4_ext_map_blocks+0xc20/0xcb0
[ 135.256475] Code:
[ 135.261433] RSP: 0018:ffffc900005939f8 EFLAGS: 00010246
[ 135.262847] RAX: 0000000000000024 RBX: ffffc90000593b70 RCX: 0000000000000023
[ 135.264765] RDX: ffff8880038e5f10 RSI: 0000000000000003 RDI: ffff8880046e922c
[ 135.266670] RBP: ffff8880046e9348 R08: 0000000000000001 R09: ffff888002ca580c
[ 135.268576] R10: 0000000000002602 R11: 0000000000000000 R12: 0000000000000024
[ 135.270477] R13: 0000000000000000 R14: 0000000000000024 R15: 0000000000000000
[ 135.272394] FS: 00007fdabdc56740(0000) GS:ffff88807dd00000(0000) knlGS:0000000000000000
[ 135.274510] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 135.276075] CR2: 00007ffc26bd4f00 CR3: 0000000006261004 CR4: 0000000000170ea0
[ 135.277952] Call Trace:
[ 135.278635] <TASK>
[ 135.279247] ? preempt_count_add+0x6d/0xa0
[ 135.280358] ? percpu_counter_add_batch+0x55/0xb0
[ 135.281612] ? _raw_read_unlock+0x18/0x30
[ 135.282704] ext4_map_blocks+0x294/0x5a0
[ 135.283745] ? xa_load+0x6f/0xa0
[ 135.284562] ext4_mpage_readpages+0x3d6/0x770
[ 135.285646] read_pages+0x67/0x1d0
[ 135.286492] ? folio_add_lru+0x51/0x80
[ 135.287441] page_cache_ra_unbounded+0x124/0x170
[ 135.288510] filemap_get_pages+0x23d/0x5a0
[ 135.289457] ? path_openat+0xa72/0xdd0
[ 135.290332] filemap_read+0xbf/0x300
[ 135.291158] ? _raw_spin_lock_irqsave+0x17/0x40
[ 135.292192] new_sync_read+0x103/0x170
[ 135.293014] vfs_read+0x15d/0x180
[ 135.293745] ksys_read+0xa1/0xe0
[ 135.294461] do_syscall_64+0x3c/0x80
[ 135.295284] entry_SYSCALL_64_after_hwframe+0x46/0xb0
This patch simply adds an extra check in __ext4_ext_check(), verifying that
eh_entries is not 0 when eh_depth is > 0.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215941
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216283
Cc: Baokun Li <libaokun1@huawei.com>
Cc: stable@kernel.org
Signed-off-by: Luís Henriques <lhenriques@suse.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20220822094235.2690-1-lhenriques@suse.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Pull Kbuild fixes from Masahiro Yamada:
- Fix build error for the combination of SYSTEM_TRUSTED_KEYRING=y and
X509_CERTIFICATE_PARSER=m
- Fix DEBUG_INFO_SPLIT to generate debug info for GCC 11+ and Clang 12+
- Revive debug info for assembly files
- Remove unused code
* tag 'kbuild-fixes-v6.0-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
Makefile.debug: re-enable debug info for .S files
Makefile.debug: set -g unconditional on CONFIG_DEBUG_INFO_SPLIT
certs: make system keyring depend on built-in x509 parser
Kconfig: remove unused function 'menu_get_root_menu'
scripts/clang-tools: remove unused module
A couple years back we went through the kernel an automatically
converted size calculations to use struct_size() instead. The
struct_size() calculation is protected against integer overflows.
However it does not make sense to use the result from struct_size()
for additional math operations as that would negate any safeness.
Fixes: 1f3b69b6b939 ("i2c: mux: Use struct_size() in devm_kzalloc()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Peter Rosin <peda@axentia.se>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
I got an infinite loop and a WARNING report when executing a tail command
in virtiofs.
WARNING: CPU: 10 PID: 964 at fs/iomap/iter.c:34 iomap_iter+0x3a2/0x3d0
Modules linked in:
CPU: 10 PID: 964 Comm: tail Not tainted 5.19.0-rc7
Call Trace:
<TASK>
dax_iomap_rw+0xea/0x620
? __this_cpu_preempt_check+0x13/0x20
fuse_dax_read_iter+0x47/0x80
fuse_file_read_iter+0xae/0xd0
new_sync_read+0xfe/0x180
? 0xffffffff81000000
vfs_read+0x14d/0x1a0
ksys_read+0x6d/0xf0
__x64_sys_read+0x1a/0x20
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
The tail command will call read() with a count of 0. In this case,
iomap_iter() will report this WARNING, and always return 1 which casuing
the infinite loop in dax_iomap_rw().
Fixing by checking count whether is 0 in dax_iomap_rw().
Fixes: ca289e0b95af ("fsdax: switch dax_iomap_rw to use iomap_iter")
Signed-off-by: Li Jinlin <lijinlin3@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20220725032050.3873372-1-lijinlin3@huawei.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The "hmem" platform-devices that are created to represent the
platform-advertised "Soft Reserved" memory ranges end up inserting a
resource that causes the iomem_resource tree to look like this:
340000000-43fffffff : hmem.0
340000000-43fffffff : Soft Reserved
340000000-43fffffff : dax0.0
This is because insert_resource() reparents ranges when they completely
intersect an existing range.
This matters because code that uses region_intersects() to scan for a
given IORES_DESC will only check that top-level 'hmem.0' resource and
not the 'Soft Reserved' descendant.
So, to support EINJ (via einj_error_inject()) to inject errors into
memory hosted by a dax-device, be sure to describe the memory as
IORES_DESC_SOFT_RESERVED. This is a follow-on to:
commit b13a3e5fd40b ("ACPI: APEI: Fix _EINJ vs EFI_MEMORY_SP")
...that fixed EINJ support for "Soft Reserved" ranges in the first
instance.
Fixes: 262b45ae3ab4 ("x86/efi: EFI soft reservation to E820 enumeration")
Reported-by: Ricardo Sandoval Torres <ricardo.sandoval.torres@intel.com>
Tested-by: Ricardo Sandoval Torres <ricardo.sandoval.torres@intel.com>
Cc: <stable@vger.kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Omar Avelar <omar.avelar@intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Mark Gross <markgross@kernel.org>
Link: https://lore.kernel.org/r/166397075670.389916.7435722208896316387.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Using rbtree for sorting groups by average fragment size is relatively
expensive (needs rbtree update on every block freeing or allocation) and
leads to wide spreading of allocations because selection of block group
is very sentitive both to changes in free space and amount of blocks
allocated. Furthermore selecting group with the best matching average
fragment size is not necessary anyway, even more so because the
variability of fragment sizes within a group is likely large so average
is not telling much. We just need a group with large enough average
fragment size so that we have high probability of finding large enough
free extent and we don't want average fragment size to be too big so
that we are likely to find free extent only somewhat larger than what we
need.
So instead of maintaing rbtree of groups sorted by fragment size keep
bins (lists) or groups where average fragment size is in the interval
[2^i, 2^(i+1)). This structure requires less updates on block allocation
/ freeing, generally avoids chaotic spreading of allocations into block
groups, and still is able to quickly (even faster that the rbtree)
provide a block group which is likely to have a suitably sized free
space extent.
This patch reduces number of block groups used when untarring archive
with medium sized files (size somewhat above 64k which is default
mballoc limit for avoiding locality group preallocation) to about half
and thus improves write speeds for eMMC flash significantly.
Fixes: 196e402adf2e ("ext4: improve cr 0 / cr 1 group scanning")
CC: stable@kernel.org
Reported-and-tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Link: https://lore.kernel.org/all/0d81a7c2-46b7-6010-62a4-3e6cfc1628d6@i2se.com/
Link: https://lore.kernel.org/r/20220908092136.11770-5-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Pull s390 fix from Vasily Gorbik:
- Fix potential hangs in VFIO AP driver
* tag 's390-6.0-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/vfio-ap: bypass unnecessary processing of AP resources
Alexey reported that the fraction of unknown filename instances in
kallsyms grew from ~0.3% to ~10% recently; Bill and Greg tracked it down
to assembler defined symbols, which regressed as a result of:
commit b8a9092330da ("Kbuild: do not emit debug info for assembly with LLVM_IAS=1")
In that commit, I allude to restoring debug info for assembler defined
symbols in a follow up patch, but it seems I forgot to do so in
commit a66049e2cf0e ("Kbuild: make DWARF version a choice")
Link: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=31bf18645d98b4d3d7357353be840e320649a67d
Fixes: b8a9092330da ("Kbuild: do not emit debug info for assembly with LLVM_IAS=1")
Reported-by: Alexey Alexandrov <aalexand@google.com>
Reported-by: Bill Wendling <morbo@google.com>
Reported-by: Greg Thelen <gthelen@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The i2c-mlxbf.c driver is currently broken because there is a bug
in the calculation of the frequency. core_f, core_r and core_od
are components read from hardware registers and are used to
compute the frequency used to compute different timing parameters.
The shifting mechanism used to get core_f, core_r and core_od is
wrong. Use FIELD_GET to mask and shift the bitfields properly.
Fixes: b5b5b32081cd206b (i2c: mlxbf: I2C SMBus driver for Mellanox BlueField SoC)
Reviewed-by: Khalil Blaiech <kblaiech@nvidia.com>
Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
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