Pull bpf updates from Alexei Starovoitov:
"Major changes:
- Recover from BPF arena page faults using a scratch page and add
ptep_try_set() for lockless empty-slot installs on x86 and arm64.
This allows BPF kfuncs to access arena pointers directly.
The 'arena_direct_access' stable branch was created for this work
and was pulled into sched-ext and bpf-next trees (Tejun Heo, Kumar
Kartikeya Dwivedi)
- Lift old restriction and support 6+ arguments in BPF programs and
kfuncs on x86 and arm64 (Yonghong Song, Puranjay Mohan)
Other features and fixes:
- Add 24-bit BTF vlen and reclaim unused bits in the BTF UAPI to ease
addition of new BTF kinds (Alan Maguire)
- Raise the maximum BPF call chain depth from 8 to 16 frames (Alexei
Starovoitov)
- Refactor object relationship tracking in the verifier and fix a
dynptr use-after-free bug (Amery Hung)
- Harden the signed program loader and reject exclusive maps as inner
maps (Daniel Borkmann)
- Replace the verifier min/max bounds fields with a circular number
(cnum) representation and improve 32->64 bit range refinements
(Eduard Zingerman)
- Introduce the arena library and runtime (libarena) with a buddy
allocator, rbtree and SPMC queue data structures, ASAN support and
a parallel test harness. Allow subprograms to return arena pointers
and switch to a BTF type-tag based __arena annotation (Emil
Tsalapatis)
- Cache build IDs in the sleepable stackmap path and avoid faultable
build ID reads under mm locks (Ihor Solodrai)
- Introduce the tracing_multi link to attach a single BPF program to
many kernel functions at once. Allow specifying the uprobe_multi
target via FD (Jiri Olsa)
- Extend the bpf_list family of kfuncs with bpf_list_add/del(), and
bpf_list_is_first/is_last/empty() (Kaitao Cheng)
- Extend the BPF syscall with common attributes support for
prog_load, btf_load and map_create (Leon Hwang)
- Wrap rhashtable as BPF map (Mykyta Yatsenko, Herbert Xu)
- Add sleepable support for tracepoint programs and fix deadlocks in
LRU map due to NMI reentry (Mykyta Yatsenko)
- Fix OOB access in bpf_flow_keys, fix nullness analysis of inner
arrays, enforce write checks for global subprograms (Nuoqi Gui)
- Report the maximum combined stack depth and print a breakdown of
instructions processed per subprogram (Paul Chaignon)
- Add an XDP load-balancer benchmark and arm64 JIT support for stack
arguments (Puranjay Mohan)
- Add kfuncs to traverse over wakeup_sources (Samuel Wu)
- Allow sleepable BPF programs to use LPM trie maps directly (Vlad
Poenaru)
- Many more fixes and cleanups across the verifier, BTF, sockmap,
devmap, bpffs, security hooks, s390/riscv/loongarch JITs,
rqspinlock, libbpf, bpftool, selftests"
* tag 'bpf-next-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (336 commits)
selftests/bpf: Work around llvm stack overflow in crypto progs
selftests/bpf: add test for bpf_msg_pop_data() overflow
bpf, sockmap: fix integer overflow in bpf_msg_pop_data() bounds check
sockmap: Fix use-after-free in udp_bpf_recvmsg()
bpf, sockmap: keep sk_msg copy state in sync
bpf, sockmap: Fix wrong rsge offset in bpf_msg_push_data()
bpf, sockmap: reject overflowing copy + len in bpf_msg_push_data()
selftsets/bpf: Retry map update on helper_fill_hashmap()
selftests/bpf: Add test for sleepable lsm_cgroup rejection
selftests/bpf: Add test to verify the fix for bpf_setsockopt() helper
bpf: Fix bpf_get/setsockopt to tos for ipv4-mapped ipv6 socket
selftests/bpf: Avoid static LLVM linking for cross builds
selftests/bpf: Use common CFLAGS for urandom_read
selftests/bpf: Initialize operation name before use
tools/bpf: build: Append extra cflags
libbpf: Initialize CFLAGS before including Makefile.include
bpftool: Append extra host flags
bpftool: Avoid adding EXTRA_CFLAGS to HOST_CFLAGS
bpftool: Pass host flags to bootstrap libbpf
selftests/bpf: correct CONFIG_PPC64 macro name in comment
...
Compute the hash of one filesystem block's worth of zeros. A filesystem
implementation can decide to elide merkle tree blocks containing only
this hash and synthesize the contents at read time.
Let's pretend that there's a file containing 131 data block and whose
merkle tree looks roughly like this:
root
+--leaf0
| +--data0
| +--data1
| +--...
| `--data128
`--leaf1
+--data129
+--data130
`--data131
If data[0-128] are sparse holes, then leaf0 will contain a repeating
sequence of @zero_digest. Therefore, leaf0 need not be written to disk
because its contents can be synthesized.
A subsequent xfs patch will use this to reduce the size of the merkle
tree when dealing with sparse gold master disk images and the like.
Note that this works only on the first-level (data holes). fsverity
doesn't store/generate zero_digest for any higher levels.
Add a helper to pre-fill folio with hashes of empty blocks. This will be
used by iomap to synthesize blocks full of zero hashes on the fly.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Acked-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Andrey Albershteyn <aalbersh@kernel.org>
Link: https://patch.msgid.link/20260520123722.405752-5-aalbersh@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Redefine dynptr mutability and fix inconsistency in the verifier and
kfunc signatures. Dynptr mutability is at two levels. The first is
the bpf_dynptr structure and the second is the memory the dynptr points
to. The verifer currently tracks the mutability of the bpf_dynptr struct
through helper and kfunc prototypes, where "const struct bpf_dynptr *"
means the structure itself is immutable. The second level is tracked
in upper bit of bpf_dynptr->size in runtime and is not changed in this
patch.
There are two type of inconsistency in the verfier regarding the
mutability of the bpf_dynptr struct. First, there are many existing
kfuncs whose prototypes are wrong. For example, bpf_dynptr_adjust()
mutates a dynptr's start and offset but marks the argument as a const
pointer. At the same time many other kfuncs that does not mutate the
dynptr but mark themselves as mutable. Second, the verifier currently
does not honor the const qualifier in kfunc prototypes as it determines
whether tagging the arg_type with MEM_RDONLY or not based on the register
state.
Since all the verifier care is to prevent CONST_PTR_TO_DYNPTR from
being destroyed in callback and global subprogram, redefine the
mutability at the bpf_dynptr level to just bpf_dynptr_kern->data. Then,
explicitly prohibit passing CONST_PTR_TO_DYNPTR to an argument tagged
with MEM_UNINIT or OBJ_RELEASE. The mutability of a dynptr's view is not
really interesting so drop MEM_RDONLY annotation for dynptr from the
helpers and kfuncs. Plus, if the mutability of the entire bpf_dynptr
were to be done correctly, it would kill the bpf_dynptr_adjust() usage
in callback and global subporgram.
Implementation wise
- First, make sure all kfunc arg are correctly tagged: Tag the dynptr
argument of bpf_dynptr_file_discard() with OBJ_RELEASE.
- Then, in process_dynptr_func(), make sure CONST_PTR_TO_DYNPTR cannot
be passed to argument tagged with MEM_UNINIT or OBJ_RELEASE. For
MEM_UNINIT, it is already checked by is_dynptr_reg_valid_uninit().
For OBJ_RELEASE, check against OBJ_RELEASE instead of MEM_RDONLY and
drop a now identical check in unmark_stack_slots_dynptr().
- Remove the mutual exclusive check between MEM_UNINIT and MEM_RDONLY,
but don't add a MEM_UNINIT and OBJ_RELEASE version as it is obviously
wrong.
Note that while this patch stops following the C semantic for the
mutability of bpf_dynptr, the prototype of kfuncs are still fixed to
maintain the correct C semantics in the implementation. Adding or
removing the const qualifier does not break backward compatibility.
In addition, fix kfuncs dropping the const qualifier when casting the
opaque bpf_dynptr to bpf_dynptr_kern.
In test_kfunc_dynptr_param.c, initialize dynptr to 0 to avoid
-Wuninitialized-const-pointer warning.
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/bpf/20260414191014.1218567-1-ameryhung@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Pull vfs i_ino updates from Christian Brauner:
"For historical reasons, the inode->i_ino field is an unsigned long,
which means that it's 32 bits on 32 bit architectures. This has caused
a number of filesystems to implement hacks to hash a 64-bit identifier
into a 32-bit field, and deprives us of a universal identifier field
for an inode.
This changes the inode->i_ino field from an unsigned long to a u64.
This shouldn't make any material difference on 64-bit hosts, but
32-bit hosts will see struct inode grow by at least 4 bytes. This
could have effects on slabcache sizes and field alignment.
The bulk of the changes are to format strings and tracepoints, since
the kernel itself doesn't care that much about the i_ino field. The
first patch changes some vfs function arguments, so check that one out
carefully.
With this change, we may be able to shrink some inode structures. For
instance, struct nfs_inode has a fileid field that holds the 64-bit
inode number. With this set of changes, that field could be
eliminated. I'd rather leave that sort of cleanups for later just to
keep this simple"
* tag 'vfs-7.1-rc1.kino' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
nilfs2: fix 64-bit division operations in nilfs_bmap_find_target_in_group()
EVM: add comment describing why ino field is still unsigned long
vfs: remove externs from fs.h on functions modified by i_ino widening
treewide: fix missed i_ino format specifier conversions
ext4: fix signed format specifier in ext4_load_inode trace event
treewide: change inode->i_ino from unsigned long to u64
nilfs2: widen trace event i_ino fields to u64
f2fs: widen trace event i_ino fields to u64
ext4: widen trace event i_ino fields to u64
zonefs: widen trace event i_ino fields to u64
hugetlbfs: widen trace event i_ino fields to u64
ext2: widen trace event i_ino fields to u64
cachefiles: widen trace event i_ino fields to u64
vfs: widen trace event i_ino fields to u64
net: change sock.sk_ino and sock_i_ino() to u64
audit: widen ino fields to u64
vfs: widen inode hash/lookup functions to u64
On 32-bit architectures, unsigned long is only 32 bits wide, which
causes 64-bit inode numbers to be silently truncated. Several
filesystems (NFS, XFS, BTRFS, etc.) can generate inode numbers that
exceed 32 bits, and this truncation can lead to inode number collisions
and other subtle bugs on 32-bit systems.
Change the type of inode->i_ino from unsigned long to u64 to ensure that
inode numbers are always represented as 64-bit values regardless of
architecture. Update all format specifiers treewide from %lu/%lx to
%llu/%llx to match the new type, along with corresponding local variable
types.
This is the bulk treewide conversion. Earlier patches in this series
handled trace events separately to allow trace field reordering for
better struct packing on 32-bit.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20260304-iino-u64-v3-12-2257ad83d372@kernel.org
Acked-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Currently, all filesystems that support fsverity (ext4, f2fs, and btrfs)
cache the Merkle tree in the pagecache at a 64K aligned offset after the
end of the file data. This offset needs to be a multiple of the page
size, which is guaranteed only when the page size is 64K or smaller.
64K was chosen to be the "largest reasonable page size". But it isn't
the largest *possible* page size: the hexagon and powerpc ports of Linux
support 256K pages, though that configuration is rarely used.
For now, just disable support for FS_VERITY in these odd configurations
to ensure it isn't used in cases where it would have incorrect behavior.
Fixes: 671e67b47e ("fs-verity: add Kconfig and the helper functions for hashing")
Reported-by: Christoph Hellwig <hch@lst.de>
Closes: https://lore.kernel.org/r/20260119063349.GA643@lst.de
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20260221204525.30426-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Pull fsverity fixes from Eric Biggers:
- Fix a build error on parisc
- Remove the non-large-folio-aware function fsverity_verify_page()
* tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fsverity/linux:
fsverity: fix build error by adding fsverity_readahead() stub
fsverity: remove fsverity_verify_page()
f2fs: make f2fs_verify_cluster() partially large-folio-aware
f2fs: remove unnecessary ClearPageUptodate in f2fs_verify_cluster()
Pull more misc vfs updates from Christian Brauner:
"Features:
- Optimize close_range() from O(range size) to O(active FDs) by using
find_next_bit() on the open_fds bitmap instead of linearly scanning
the entire requested range. This is a significant improvement for
large-range close operations on sparse file descriptor tables.
- Add FS_XFLAG_VERITY file attribute for fs-verity files, retrievable
via FS_IOC_FSGETXATTR and file_getattr(). The flag is read-only.
Add tracepoints for fs-verity enable and verify operations,
replacing the previously removed debug printk's.
- Prevent nfsd from exporting special kernel filesystems like pidfs
and nsfs. These filesystems have custom ->open() and ->permission()
export methods that are designed for open_by_handle_at(2) only and
are incompatible with nfsd. Update the exportfs documentation
accordingly.
Fixes:
- Fix KMSAN uninit-value in ovl_fill_real() where strcmp() was used
on a non-null-terminated decrypted directory entry name from
fscrypt. This triggered on encrypted lower layers when the
decrypted name buffer contained uninitialized tail data.
The fix also adds VFS-level name_is_dot(), name_is_dotdot(), and
name_is_dot_dotdot() helpers, replacing various open-coded "." and
".." checks across the tree.
- Fix read-only fsflags not being reset together with xflags in
vfs_fileattr_set(). Currently harmless since no read-only xflags
overlap with flags, but this would cause inconsistencies for any
future shared read-only flag
- Return -EREMOTE instead of -ESRCH from PIDFD_GET_INFO when the
target process is in a different pid namespace. This lets userspace
distinguish "process exited" from "process in another namespace",
matching glibc's pidfd_getpid() behavior
Cleanups:
- Use C-string literals in the Rust seq_file bindings, replacing the
kernel::c_str!() macro (available since Rust 1.77)
- Fix typo in d_walk_ret enum comment, add porting notes for the
readlink_copy() calling convention change"
* tag 'vfs-7.0-rc1.misc.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
fs: add porting notes about readlink_copy()
pidfs: return -EREMOTE when PIDFD_GET_INFO is called on another ns
nfsd: do not allow exporting of special kernel filesystems
exportfs: clarify the documentation of open()/permission() expotrfs ops
fsverity: add tracepoints
fs: add FS_XFLAG_VERITY for fs-verity files
rust: seq_file: replace `kernel::c_str!` with C-Strings
fs: dcache: fix typo in enum d_walk_ret comment
ovl: use name_is_dot* helpers in readdir code
fs: add helpers name_is_dot{,dot,_dotdot}
ovl: Fix uninit-value in ovl_fill_real
fs: reset read-only fsflags together with xflags
fs/file: optimize close_range() complexity from O(N) to O(Sparse)
Pull fsverity updates from Eric Biggers:
"fsverity cleanups, speedup, and memory usage optimization from
Christoph Hellwig:
- Move some logic into common code
- Fix btrfs to reject truncates of fsverity files
- Improve the readahead implementation
- Store each inode's fsverity_info in a hash table instead of using a
pointer in the filesystem-specific part of the inode.
This optimizes for memory usage in the usual case where most files
don't have fsverity enabled.
- Look up the fsverity_info fewer times during verification, to
amortize the hash table overhead"
* tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fsverity/linux:
fsverity: remove inode from fsverity_verification_ctx
fsverity: use a hashtable to find the fsverity_info
btrfs: consolidate fsverity_info lookup
f2fs: consolidate fsverity_info lookup
ext4: consolidate fsverity_info lookup
fs: consolidate fsverity_info lookup in buffer.c
fsverity: push out fsverity_info lookup
fsverity: deconstify the inode pointer in struct fsverity_info
fsverity: kick off hash readahead at data I/O submission time
ext4: move ->read_folio and ->readahead to readpage.c
readahead: push invalidate_lock out of page_cache_ra_unbounded
fsverity: don't issue readahead for non-ENOENT errors from __filemap_get_folio
fsverity: start consolidating pagecache code
fsverity: pass struct file to ->write_merkle_tree_block
f2fs: don't build the fsverity work handler for !CONFIG_FS_VERITY
ext4: don't build the fsverity work handler for !CONFIG_FS_VERITY
fs,fsverity: clear out fsverity_info from common code
fs,fsverity: reject size changes on fsverity files in setattr_prepare
Use the kernel's resizable hash table (rhashtable) to find the
fsverity_info. This way file systems that want to support fsverity don't
have to bloat every inode in the system with an extra pointer. The
trade-off is that looking up the fsverity_info is a bit more expensive
now, but the main operations are still dominated by I/O and hashing
overhead.
The rhashtable implementations requires no external synchronization, and
the _fast versions of the APIs provide the RCU critical sections required
by the implementation. Because struct fsverity_info is only removed on
inode eviction and does not contain a reference count, there is no need
for an extended critical section to grab a reference or validate the
object state. The file open path uses rhashtable_lookup_get_insert_fast,
which can either find an existing object for the hash key or insert a
new one in a single atomic operation, so that concurrent opens never
instantiate duplicate fsverity_info structure. FS_IOC_ENABLE_VERITY must
already be synchronized by a combination of i_rwsem and file system flags
and uses rhashtable_lookup_insert_fast, which errors out on an existing
object for the hash key as an additional safety check.
Because insertion into the hash table now happens before S_VERITY is set,
fsverity just becomes a barrier and a flag check and doesn't have to look
up the fsverity_info at all, so there is only a single lookup per
->read_folio or ->readahead invocation. For btrfs there is an additional
one for each bio completion, while for ext4 and f2fs the fsverity_info
is stored in the per-I/O context and reused for the completion workqueue.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Link: https://lore.kernel.org/r/20260202060754.270269-12-hch@lst.de
[EB: folded in fix for missing fsverity_free_info()]
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Pass a struct fsverity_info to the verification and readahead helpers,
and push the lookup into the callers. Right now this is a very dumb
almost mechanic move that open codes a lot of fsverity_info_addr() calls
in the file systems. The subsequent patches will clean this up.
This prepares for reducing the number of fsverity_info lookups, which
will allow to amortize them better when using a more expensive lookup
method.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Acked-by: David Sterba <dsterba@suse.com> # btrfs
Link: https://lore.kernel.org/r/20260202060754.270269-7-hch@lst.de
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Currently all reads of the fsverity hashes are kicked off from the data
I/O completion handler, leading to needlessly dependent I/O. This is
worked around a bit by performing readahead on the level 0 nodes, but
still fairly ineffective.
Switch to a model where the ->read_folio and ->readahead methods instead
kick off explicit readahead of the fsverity hashed so they are usually
available at I/O completion time.
For 64k sequential reads on my test VM this improves read performance
from 2.4GB/s - 2.6GB/s to 3.5GB/s - 3.9GB/s. The improvements for
random reads are likely to be even bigger.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com> # btrfs
Link: https://lore.kernel.org/r/20260202060754.270269-5-hch@lst.de
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Require the invalidate_lock to be held over calls to
page_cache_ra_unbounded instead of acquiring it in this function.
This prepares for calling page_cache_ra_unbounded from ->readahead for
fsverity read-ahead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20260202060754.270269-3-hch@lst.de
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
ext4 and f2fs are largely using the same code to read a page full
of Merkle tree blocks from the page cache, and the upcoming xfs
fsverity support would add another copy.
Move the ext4 code to fs/verity/ and use it in f2fs as well. For f2fs
this removes the previous f2fs-specific error injection, but otherwise
the behavior remains unchanged.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andrey Albershteyn <aalbersh@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Link: https://lore.kernel.org/r/20260128152630.627409-7-hch@lst.de
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Add the check to reject truncates of fsverity files directly to
setattr_prepare instead of requiring the file system to handle it.
Besides removing boilerplate code, this also fixes the complete lack of
such check in btrfs.
Fixes: 146054090b ("btrfs: initial fsverity support")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Link: https://lore.kernel.org/r/20260128152630.627409-2-hch@lst.de
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Pull interleaved SHA-256 hashing support from Eric Biggers:
"Optimize fsverity with 2-way interleaved hashing
Add support for 2-way interleaved SHA-256 hashing to lib/crypto/, and
make fsverity use it for faster file data verification. This improves
fsverity performance on many x86_64 and arm64 processors.
Later, I plan to make dm-verity use this too"
* tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fsverity/linux:
fsverity: Use 2-way interleaved SHA-256 hashing when supported
fsverity: Remove inode parameter from fsverity_hash_block()
lib/crypto: tests: Add tests and benchmark for sha256_finup_2x()
lib/crypto: x86/sha256: Add support for 2-way interleaved hashing
lib/crypto: arm64/sha256: Add support for 2-way interleaved hashing
lib/crypto: sha256: Add support for 2-way interleaved hashing
Pull vfs workqueue updates from Christian Brauner:
"This contains various workqueue changes affecting the filesystem
layer.
Currently if a user enqueue a work item using schedule_delayed_work()
the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies
to schedule_work() that is using system_wq and queue_work(), that
makes use again of WORK_CPU_UNBOUND.
This replaces the use of system_wq and system_unbound_wq. system_wq is
a per-CPU workqueue which isn't very obvious from the name and
system_unbound_wq is to be used when locality is not required.
So this renames system_wq to system_percpu_wq, and system_unbound_wq
to system_dfl_wq.
This also adds a new WQ_PERCPU flag to allow the fs subsystem users to
explicitly request the use of per-CPU behavior. Both WQ_UNBOUND and
WQ_PERCPU flags coexist for one release cycle to allow callers to
transition their calls. WQ_UNBOUND will be removed in a next release
cycle"
* tag 'vfs-6.18-rc1.workqueue' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
fs: WQ_PERCPU added to alloc_workqueue users
fs: replace use of system_wq with system_percpu_wq
fs: replace use of system_unbound_wq with system_dfl_wq
Linus Torvalds
Andrey Albershteyn
Amery Hung
Jeff Layton
Eric Biggers
Christoph Hellwig
Puranjay Mohan