Linux kernel
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There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
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Zenghui reports that since 1396e89e09f0 ("genirq/msi: Move prepare() call
to per-device allocation"), his Multi-MSI capable device isn't working
anymore.
This is a consequence of 15c72f824b32 ("PCI/MSI: Add support for per device
MSI[X] domains"), which always creates a MSI domain of size 1, even in the
presence of Multi-MSI.
While this was somehow working until then, moving the .prepare() call ends
up sizing the ITS table with a tiny value for this device, and making the
endpoint driver unhappy.
Instead, always create the domain and call the .prepare() helper with the
maximum expected size.
Fixes: 1396e89e09f0 ("genirq/msi: Move prepare() call to per-device allocation")
Fixes: 15c72f824b32 ("PCI/MSI: Add support for per device MSI[X] domains")
Reported-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Zenghui Yu <yuzenghui@huawei.com>
Reviewed-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Link: https://lore.kernel.org/all/20250603141801.915305-1-maz@kernel.org
Closes: https://lore.kernel.org/r/0b1d7aec-1eac-a9cd-502a-339e216e08a1@huawei.com
Pull NFS clent updates from Anna Schumaker:
"New Features:
- Implement the Sunrpc rfc2203 rpcsec_gss sequence number cache
- Add support for FALLOC_FL_ZERO_RANGE on NFS v4.2
- Add a localio sysfs attribute
Stable Fixes:
- Fix double-unlock bug in nfs_return_empty_folio()
- Don't check for OPEN feature support in v4.1
- Always probe for LOCALIO support asynchronously
- Prevent hang on NFS mounts with xprtsec=[m]tls
Other Bugfixes:
- xattr handlers should check for absent nfs filehandles
- Fix setattr caching of TIME_[MODIFY|ACCESS]_SET when timestamps are
delegated
- Fix listxattr to return selinux security labels
- Connect to NFSv3 DS using TLS if MDS connection uses TLS
- Clear SB_RDONLY before getting a superblock, and ignore when
remounting
- Fix incorrect handling of NFS error codes in nfs4_do_mkdir()
- Various nfs_localio fixes from Neil Brown that include fixing an
rcu compilation error found by older gcc versions.
- Update stats on flexfiles pNFS DSes when receiving NFS4ERR_DELAY
Cleanups:
- Add a refcount tracker for struct net in the nfs_client
- Allow FREE_STATEID to clean up delegations
- Always set NLINK even if the server doesn't support it
- Cleanups to the NFS folio writeback code
- Remove dead code from xs_tcp_tls_setup_socket()"
* tag 'nfs-for-6.16-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (30 commits)
flexfiles/pNFS: update stats on NFS4ERR_DELAY for v4.1 DSes
nfs_localio: change nfsd_file_put_local() to take a pointer to __rcu pointer
nfs_localio: protect race between nfs_uuid_put() and nfs_close_local_fh()
nfs_localio: duplicate nfs_close_local_fh()
nfs_localio: simplify interface to nfsd for getting nfsd_file
nfs_localio: always hold nfsd net ref with nfsd_file ref
nfs_localio: use cmpxchg() to install new nfs_file_localio
SUNRPC: Remove dead code from xs_tcp_tls_setup_socket()
SUNRPC: Prevent hang on NFS mount with xprtsec=[m]tls
nfs: fix incorrect handling of large-number NFS errors in nfs4_do_mkdir()
nfs: ignore SB_RDONLY when remounting nfs
nfs: clear SB_RDONLY before getting superblock
NFS: always probe for LOCALIO support asynchronously
pnfs/flexfiles: connect to NFSv3 DS using TLS if MDS connection uses TLS
NFS: add localio to sysfs
nfs: use writeback_iter directly
nfs: refactor nfs_do_writepage
nfs: don't return AOP_WRITEPAGE_ACTIVATE from nfs_do_writepage
nfs: fold nfs_page_async_flush into nfs_do_writepage
NFSv4: Always set NLINK even if the server doesn't support it
...
Pull smb client updates from Steve French:
- multichannel fixes (mostly reconnect related), and clarification of
locking documentation
- automount null pointer check fix
- fixes to add support for ParentLeaseKey
- minor cleanup
- smb1/cifs fixes
* tag 'v6.16-rc-part1-smb-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: update the lock ordering comments with new mutex
cifs: dns resolution is needed only for primary channel
cifs: update dstaddr whenever channel iface is updated
cifs: reset connections for all channels when reconnect requested
smb: client: use ParentLeaseKey in cifs_do_create
smb: client: use ParentLeaseKey in open_cached_dir
smb: client: add ParentLeaseKey support
cifs: Fix cifs_query_path_info() for Windows NT servers
cifs: Fix validation of SMB1 query reparse point response
cifs: Correctly set SMB1 SessionKey field in Session Setup Request
cifs: Fix encoding of SMB1 Session Setup NTLMSSP Request in non-UNICODE mode
smb: client: add NULL check in automount_fullpath
smb: client: Remove an unused function and variable
On NFS4ERR_DELAY nfs slient updates its stats, but misses for
flexfiles v4.1 DSes.
Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Pull device mapper updates from Mikulas Patocka:
- better error handling when reloading a table
- use use generic disable_* functions instead of open coding them
- lock queue limits when reading them
- remove unneeded kvfree from alloc_targets
- fix BLK_FEAT_ATOMIC_WRITES
- pass through operations on wrapped inline crypto keys
- dm-verity:
- use softirq context only when !need_resched()
- fix a memory leak if some arguments are specified multiple times
- dm-mpath:
- interface for explicit probing of active paths
- replace spin_lock_irqsave with spin_lock_irq
- dm-delay: don't busy-wait in kthread
- dm-bufio: remove maximum age based eviction
- dm-flakey: various fixes
- vdo indexer: don't read request structure after enqueuing
- dm-zone: Use bdev_*() helper functions where applicable
- dm-mirror: fix a tiny race condition
- dm-stripe: small code cleanup
* tag 'for-6.16/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (29 commits)
dm-stripe: small code cleanup
dm-verity: fix a memory leak if some arguments are specified multiple times
dm-mirror: fix a tiny race condition
dm-table: check BLK_FEAT_ATOMIC_WRITES inside limits_lock
dm mpath: replace spin_lock_irqsave with spin_lock_irq
dm-mpath: Don't grab work_mutex while probing paths
dm-zone: Use bdev_*() helper functions where applicable
dm vdo indexer: don't read request structure after enqueuing
dm: pass through operations on wrapped inline crypto keys
blk-crypto: export wrapped key functions
dm-table: Set BLK_FEAT_ATOMIC_WRITES for target queue limits
dm mpath: Interface for explicit probing of active paths
dm: Allow .prepare_ioctl to handle ioctls directly
dm-flakey: make corrupting read bios work
dm-flakey: remove useless ERROR_READS check in flakey_end_io
dm-flakey: error all IOs when num_features is absent
dm-flakey: Clean up parsing messages
dm: remove unneeded kvfree from alloc_targets
dm-bufio: remove maximum age based eviction
dm-verity: use softirq context only when !need_resched()
...
The lock ordering rules listed as comments in cifsglob.h were
missing some lock details and also the fid_lock.
Updated those notes in this commit.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Instead of calling xchg() and unrcu_pointer() before
nfsd_file_put_local(), we now pass pointer to the __rcu pointer and call
xchg() and unrcu_pointer() inside that function.
Where unrcu_pointer() is currently called the internals of "struct
nfsd_file" are not known and that causes older compilers such as gcc-8
to complain.
In some cases we have a __kernel (aka normal) pointer not an __rcu
pointer so we need to cast it to __rcu first. This is strictly a
weakening so no information is lost. Somewhat surprisingly, this cast
is accepted by gcc-8.
This has the pleasing result that the cmpxchg() which sets ro_file and
rw_file, and also the xchg() which clears them, are both now in the nfsd
code.
Reported-by: Pali Rohár <pali@kernel.org>
Reported-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Fixes: 86e00412254a ("nfs: cache all open LOCALIO nfsd_file(s) in client")
Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Pull perf tools updates from Arnaldo Carvalho de Melo:
"perf report/top/annotate TUI:
- Accept the left arrow key as a Zoom out if done on the first column
- Show if source code toggle status in title, to help spotting bugs
with the various disassemblers (capstone, llvm, objdump)
- Provide feedback on unhandled hotkeys
Build:
- Better inform when certain features are not available with warnings
in the build process and in 'perf version --build-options' or 'perf -vv'
perf record:
- Improve the --off-cpu code by synthesizing events for switch-out ->
switch-in intervals using a BPF program. This can be fine tuned
using a --off-cpu-thresh knob
perf report:
- Add 'tgid' sort key
perf mem/c2c:
- Add 'op', 'cache', 'snoop', 'dtlb' output fields
- Add support for 'ldlat' on AMD IBS (Instruction Based Sampling)
perf ftrace:
- Use process/session specific trace settings instead of messing with
the global ftrace knobs
perf trace:
- Implement syscall summary in BPF
- Support --summary-mode=cgroup
- Always print return value for syscalls returning a pid
- The rseq and set_robust_list don't return a pid, just -errno
perf lock contention:
- Symbolize zone->lock using BTF
- Add -J/--inject-delay option to estimate impact on application
performance by optimization of kernel locking behavior
perf stat:
- Improve hybrid support for the NMI watchdog warning
Symbol resolution:
- Handle 'u' and 'l' symbols in /proc/kallsyms, resolving some Rust
symbols
- Improve Rust demangler
Hardware tracing:
Intel PT:
- Fix PEBS-via-PT data_src
- Do not default to recording all switch events
- Fix pattern matching with python3 on the SQL viewer script
arm64:
- Fixups for the hip08 hha PMU
Vendor events:
- Update Intel events/metrics files for alderlake, alderlaken,
arrowlake, bonnell, broadwell, broadwellde, broadwellx,
cascadelakex, clearwaterforest, elkhartlake, emeraldrapids,
grandridge, graniterapids, haswell, haswellx, icelake, icelakex,
ivybridge, ivytown, jaketown, lunarlake, meteorlake, nehalemep,
nehalemex, rocketlake, sandybridge, sapphirerapids, sierraforest,
skylake, skylakex, snowridgex, tigerlake, westmereep-dp,
westmereep-sp, westmereep-sx
python support:
- Add support for event counts in the python binding, add a
counting.py example
perf list:
- Display the PMU name associated with a perf metric in JSON
perf test:
- Hybrid improvements for metric value validation test
- Fix LBR test by ignoring idle task
- Add AMD IBS sw filter ana d'ldlat' tests
- Add 'perf trace --summary-mode=cgroup' test
- Add tests for the various language symbol demanglers
Miscellaneous:
- Allow specifying the cpu an event will be tied using '-e
event/cpu=N/'
- Sync various headers with the kernel sources
- Add annotations to use clang's -Wthread-safety and fix some
problems it detected
- Make dump_stack() use perf's symbol resolution to provide better
backtraces
- Intel TPEBS support cleanups and fixes. TPEBS stands for Timed PEBS
(Precision Event-Based Sampling), that adds timing info, the
retirement latency of instructions
- Various memory allocation (some detected by ASAN) and reference
counting fixes
- Add a 8-byte aligned PERF_RECORD_COMPRESSED2 to replace
PERF_RECORD_COMPRESSED
- Skip unsupported event types in perf.data files, don't stop when
finding one
- Improve lookups using hashmaps and binary searches"
* tag 'perf-tools-for-v6.16-1-2025-06-03' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (206 commits)
perf callchain: Always populate the addr_location map when adding IP
perf lock contention: Reject more than 10ms delays for safety
perf trace: Set errpid to false for rseq and set_robust_list
perf symbol: Move demangling code out of symbol-elf.c
perf trace: Always print return value for syscalls returning a pid
perf script: Print PERF_AUX_FLAG_COLLISION flag
perf mem: Show absolute percent in mem_stat output
perf mem: Display sort order only if it's available
perf mem: Describe overhead calculation in brief
perf record: Fix incorrect --user-regs comments
Revert "perf thread: Ensure comm_lock held for comm_list"
perf test trace_summary: Skip --bpf-summary tests if no libbpf
perf test intel-pt: Skip jitdump test if no libelf
perf intel-tpebs: Avoid race when evlist is being deleted
perf test demangle-java: Don't segv if demangling fails
perf symbol: Fix use-after-free in filename__read_build_id
perf pmu: Avoid segv for missing name/alias_name in wildcarding
perf machine: Factor creating a "live" machine out of dwarf-unwind
perf test: Add AMD IBS sw filter test
perf mem: Count L2 HITM for c2c statistic
...
This commit doesn't fix any bug, it is just code cleanup. Use the
function format_dev_t instead of sprintf, because format_dev_t does the
same thing.
Remove the useless memset call.
An unsigned integer can take at most 10 digits, so extend the array size
to 22. (note that because the range of minor and major numbers is limited,
the size 16 could not be exceeded, thus this function couldn't write
beyond string end)
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
When calling cifs_reconnect, before the connection to the
server is reestablished, the code today does a DNS resolution and
updates server->dstaddr.
However, this is not necessary for secondary channels. Secondary
channels use the interface list returned by the server to decide
which address to connect to. And that happens after tcon is reconnected
and server interfaces are requested.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
nfs_uuid_put() and nfs_close_local_fh() can race if a "struct
nfs_file_localio" is released at the same time that nfsd calls
nfs_localio_invalidate_clients().
It is important that neither of these functions completes after the
other has started looking at a given nfs_file_localio and before it
finishes.
If nfs_uuid_put() exits while nfs_close_local_fh() is closing ro_file
and rw_file it could return to __nfd_file_cache_purge() while some files
are still referenced so the purge may not succeed.
If nfs_close_local_fh() exits while nfsd_uuid_put() is still closing the
files then the "struct nfs_file_localio" could be freed while
nfsd_uuid_put() is still looking at it. This side is currently handled
by copying the pointers out of ro_file and rw_file before deleting from
the list in nfsd_uuid. We need to preserve this while ensuring that
nfsd_uuid_put() does wait for nfs_close_local_fh().
This patch use nfl->uuid and nfl->list to provide the required
interlock.
nfs_uuid_put() removes the nfs_file_localio from the list, then drops
locks and puts the two files, then reclaims the spinlock and sets
->nfs_uuid to NULL.
nfs_close_local_fh() operates in the reverse order, setting ->nfs_uuid
to NULL, then closing the files, then unlinking from the list.
If nfs_uuid_put() finds that ->nfs_uuid is already NULL, it waits for
the nfs_file_localio to be removed from the list. If
nfs_close_local_fh() find that it has already been unlinked it waits for
->nfs_uuid to become NULL. This ensure that one of the two tries to
close the files, but they each waits for the other.
As nfs_uuid_put() is making the list empty, change from a
list_for_each_safe loop to a while that always takes the first entry.
This makes the intent more clear.
Also don't move the list to a temporary local list as this would defeat
the guarantees required for the interlock.
Fixes: 86e00412254a ("nfs: cache all open LOCALIO nfsd_file(s) in client")
Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Pull tracing fixes from Steven Rostedt:
- Fix UAF in module unload in ftrace when there's a bug in the module
If a module is buggy and triggers ftrace_disable which is set when an
anomaly is detected, when it gets unloaded it doesn't free the hooks
into kallsyms, and when a kallsyms lookup is performed it may access
the mod->modname field and crash via UAF.
Fix this by still freeing the mod_maps that are attached to kallsyms
on module unload regardless if ftrace_disable is set or not.
- Do not bother allocating mod_maps for kallsyms if ftrace_disable is
set
- Remove unused trace events
When a trace event or tracepoint is created but not used, it still
creates the code and data structures needed for that trace event.
This just wastes memory.
Remove the trace events that are created but not used. This does not
remove trace events that are created but are not used due configs not
being set. That will be handled later. This only removes events that
have no user under any config.
* tag 'trace-v6.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
fsdax: Remove unused trace events for dax insert mapping
genirq/matrix: Remove unused irq_matrix_alloc_reserved tracepoint
xdp: Remove unused mem_return_failed event
ftrace: Don't allocate ftrace module map if ftrace is disabled
ftrace: Fix UAF when lookup kallsym after ftrace disabled
Dropping symbols also meant the callchain maps wasn't populated, but
the callchain map is needed to find the DSO.
Plumb the symbols option better, falling back to thread__find_map()
rather than thread__find_symbol() when symbols are disabled.
Fixes: 02b2705017d2e5ad ("perf callchain: Allow symbols to be optional when resolving a callchain")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.ibm.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Chaitanya S Prakash <chaitanyas.prakash@arm.com>
Cc: Charlie Jenkins <charlie@rivosinc.com>
Cc: Chun-Tse Shao <ctshao@google.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: Graham Woodward <graham.woodward@arm.com>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ilkka Koskinen <ilkka@os.amperecomputing.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Krzysztof Łopatowski <krzysztof.m.lopatowski@gmail.com>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Levi Yun <yeoreum.yun@arm.com>
Cc: Li Huafei <lihuafei1@huawei.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Liška <martin.liska@hey.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Matt Fleming <matt@readmodwrite.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Song Liu <song@kernel.org>
Cc: Steinar H. Gunderson <sesse@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Steve Clevenger <scclevenger@os.amperecomputing.com>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Cc: Veronika Molnarova <vmolnaro@redhat.com>
Cc: Weilin Wang <weilin.wang@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Cc: Yujie Liu <yujie.liu@intel.com>
Cc: Zhongqiu Han <quic_zhonhan@quicinc.com>
Cc: Zixian Cai <fzczx123@gmail.com>
Link: https://lore.kernel.org/r/20250529044000.759937-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If some of the arguments "check_at_most_once", "ignore_zero_blocks",
"use_fec_from_device", "root_hash_sig_key_desc" were specified more than
once on the target line, a memory leak would happen.
This commit fixes the memory leak. It also fixes error handling in
verity_verify_sig_parse_opt_args.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
When the server interface info changes (more common in clustered
servers like Azure Files), the per-channel iface gets updated.
However, this did not update the corresponding dstaddr. As a result
these channels will still connect (or try connecting) to older addresses.
Fixes: b54034a73baf ("cifs: during reconnect, update interface if necessary")
Cc: <stable@vger.kernel.org>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
nfs_close_local_fh() is called from two different places for quite
different use case.
It is called from nfs_uuid_put() when the nfs_uuid is being detached -
possibly because the nfs server is not longer serving that filesystem.
In this case there will always be an nfs_uuid and so rcu_read_lock() is
not needed.
It is also called when the nfs_file_localio is no longer needed. In
this case there may not be an active nfs_uuid.
These two can race, and handling the race properly while avoiding
excessive locking will require different handling on each side.
This patch prepares the way by opencoding nfs_close_local_fh() into
nfs_uuid_put(), then simplifying the code there as befits the context.
Fixes: 86e00412254a ("nfs: cache all open LOCALIO nfsd_file(s) in client")
Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>