David Howells <dhowells@redhat.com> says:
Here are some miscellaneous fixes and changes for netfslib, if you could
pull them:
(1) Fix an oops in write-retry due to mis-resetting the I/O iterator.
(2) Fix the recording of transferred bytes for short DIO reads.
(3) Fix a request's work item to not require a reference, thereby avoiding
the need to get rid of it in BH/IRQ context.
(4) Fix waiting and waking to be consistent about the waitqueue used.
* patches from https://lore.kernel.org/20250519090707.2848510-1-dhowells@redhat.com:
netfs: Fix wait/wake to be consistent about the waitqueue used
netfs: Fix the request's work item to not require a ref
netfs: Fix setting of transferred bytes with short DIO reads
netfs: Fix oops in write-retry from mis-resetting the subreq iterator
Link: https://lore.kernel.org/20250519090707.2848510-1-dhowells@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
When the netfs_io_request struct's work item is queued, it must be supplied
with a ref to the work item struct to prevent it being deallocated whilst
on the queue or whilst it is being processed. This is tricky to manage as
we have to get a ref before we try and queue it and then we may find it's
already queued and is thus already holding a ref - in which case we have to
try and get rid of the ref again.
The problem comes if we're in BH or IRQ context and need to drop the ref:
if netfs_put_request() reduces the count to 0, we have to do the cleanup -
but the cleanup may need to wait.
Fix this by adding a new work item to the request, ->cleanup_work, and
dispatching that when the refcount hits zero. That can then synchronously
cancel any outstanding work on the main work item before doing the cleanup.
Adding a new work item also deals with another problem upstream where it's
sometimes changing the work func in the put function and requeuing it -
which has occasionally in the past caused the cleanup to happen
incorrectly.
As a bonus, this allows us to get rid of the 'was_async' parameter from a
bunch of functions. This indicated whether the put function might not be
permitted to sleep.
Fixes: 3d3c950467 ("netfs: Provide readahead and readpage netfs helpers")
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519090707.2848510-4-dhowells@redhat.com
cc: Paulo Alcantara <pc@manguebit.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Steve French <stfrench@microsoft.com>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
A netfslib request comprises an ordered stream of subrequests that, when
doing an unbuffered/DIO read, are contiguous. The subrequests may be
performed in parallel, but may not be fully completed.
For instance, if we try and make a 256KiB DIO read from a 3-byte file with
a 64KiB rsize and 256KiB bsize, netfslib will attempt to make a read of
256KiB, broken up into four 64KiB subreads, with the expectation that the
first will be short and the subsequent three be completely devoid - but we
do all four on the basis that the file may have been changed by a third
party.
The read-collection code, however, walks through all the subreqs and
advances the notion of how much data has been read in the stream to the
start of each subreq plus its amount transferred (which are 3, 0, 0, 0 for
the example above) - which gives an amount apparently read of 3*64KiB -
which is incorrect.
Fix the collection code to cut short the calculation of the transferred
amount with the first short subrequest in an unbuffered read; everything
beyond that must be ignored as there's a hole that cannot be filled. This
applies both to shortness due to hitting the EOF and shortness due to an
error.
This is achieved by setting a flag on the request when we collect the first
short subrequest (collection is done in ascending order).
This can be tested by mounting a cifs volume with rsize=65536,bsize=262144
and doing a 256k DIO read of a very small file (e.g. 3 bytes). read()
should return 3, not >3.
This problem came in when netfs_read_collection() set rreq->transferred to
stream->transferred, even for DIO. Prior to that, netfs_rreq_assess_dio()
just went over the list and added up the subreqs till it met a short one -
but now the subreqs are discarded earlier.
Fixes: e2d46f2ec3 ("netfs: Change the read result collector to only use one work item")
Reported-by: Nicolas Baranger <nicolas.baranger@3xo.fr>
Closes: https://lore.kernel.org/all/10bec2430ed4df68bde10ed95295d093@3xo.fr/
Signed-off-by: "Paulo Alcantara (Red Hat)" <pc@manguebit.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519090707.2848510-3-dhowells@redhat.com
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Fix the resetting of the subrequest iterator in netfs_retry_write_stream()
to use the iterator-reset function as the iterator may have been shortened
by a previous retry. In such a case, the amount of data to be written by
the subrequest is not "subreq->len" but "subreq->len -
subreq->transferred".
Without this, KASAN may see an error in iov_iter_revert():
BUG: KASAN: slab-out-of-bounds in iov_iter_revert lib/iov_iter.c:633 [inline]
BUG: KASAN: slab-out-of-bounds in iov_iter_revert+0x443/0x5a0 lib/iov_iter.c:611
Read of size 4 at addr ffff88802912a0b8 by task kworker/u32:7/1147
CPU: 1 UID: 0 PID: 1147 Comm: kworker/u32:7 Not tainted 6.15.0-rc6-syzkaller-00052-g9f35e33144ae #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events_unbound netfs_write_collection_worker
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xc3/0x670 mm/kasan/report.c:521
kasan_report+0xe0/0x110 mm/kasan/report.c:634
iov_iter_revert lib/iov_iter.c:633 [inline]
iov_iter_revert+0x443/0x5a0 lib/iov_iter.c:611
netfs_retry_write_stream fs/netfs/write_retry.c:44 [inline]
netfs_retry_writes+0x166d/0x1a50 fs/netfs/write_retry.c:231
netfs_collect_write_results fs/netfs/write_collect.c:352 [inline]
netfs_write_collection_worker+0x23fd/0x3830 fs/netfs/write_collect.c:374
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Fixes: cd0277ed0c ("netfs: Use new folio_queue data type and iterator instead of xarray iter")
Reported-by: syzbot+25b83a6f2c702075fcbc@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=25b83a6f2c702075fcbc
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519090707.2848510-2-dhowells@redhat.com
Tested-by: syzbot+25b83a6f2c702075fcbc@syzkaller.appspotmail.com
cc: Paulo Alcantara <pc@manguebit.com>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
David Howells <dhowells@redhat.com> says:
Here are some miscellaneous very minor cleanups for netfslib for the next
merge window, primarily from Max Kellermann, if you could pull them.
(1) Remove NETFS_SREQ_SEEK_DATA_READ.
(2) Remove NETFS_INVALID_WRITE.
(3) Remove NETFS_ICTX_WRITETHROUGH.
(4) Remove NETFS_READ_HOLE_CLEAR.
(5) Reorder structs to eliminate holes.
(6) Remove netfs_io_request::ractl.
(7) Only provide proc_link field if CONFIG_PROC_FS=y.
(8) Remove folio_queue::marks3.
(9) Remove NETFS_RREQ_DONT_UNLOCK_FOLIOS.
(10) Remove NETFS_RREQ_BLOCKED.
* patches from https://lore.kernel.org/20250519134813.2975312-1-dhowells@redhat.com:
fs/netfs: remove unused flag NETFS_RREQ_BLOCKED
fs/netfs: remove unused flag NETFS_RREQ_DONT_UNLOCK_FOLIOS
folio_queue: remove unused field `marks3`
fs/netfs: declare field `proc_link` only if CONFIG_PROC_FS=y
fs/netfs: remove `netfs_io_request.ractl`
fs/netfs: reorder struct fields to eliminate holes
fs/netfs: remove unused enum choice NETFS_READ_HOLE_CLEAR
fs/netfs: remove unused flag NETFS_ICTX_WRITETHROUGH
fs/netfs: remove unused source NETFS_INVALID_WRITE
fs/netfs: remove unused flag NETFS_SREQ_SEEK_DATA_READ
Link: https://lore.kernel.org/20250519134813.2975312-1-dhowells@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Bring in the netfs API documentation updates which had been in the
vfs-6.16.misc branch for most of this cycle. So don't needlessly rewrite
the vfs-6.16.misc by dropping it from that branch and moving it to
vfs-6.16.netfs. Simply merge vfs-6.16.misc into vfs-6.16.netfs.
Signed-off-by: Christian Brauner <brauner@kernel.org>
Christian Brauner <brauner@kernel.org> says:
* Anonymous inodes currently don't come with a proper mode causing
issues in the kernel when we want to add useful VFS debug assert. Fix
that by giving them a proper mode and masking it off when we report it
to userspace which relies on them not having any mode.
* Anonymous inodes currently allow to change inode attributes because
the VFS falls back to simple_setattr() if i_op->setattr isn't
implemented. This means the ownership and mode for every single user
of anon_inode_inode can be changed. Block that as it's either useless
or actively harmful. If specific ownership is needed the respective
subsystem should allocate anonymous inodes from their own private
superblock.
* Port pidfs to the new anon_inode_{g,s}etattr() helpers.
* Add proper tests for anonymous inode behavior.
The anonymous inode specific fixes should ideally be backported to all
LTS kernels.
* patches from https://lore.kernel.org/20250407-work-anon_inode-v1-0-53a44c20d44e@kernel.org:
selftests/filesystems: add fourth test for anonymous inodes
selftests/filesystems: add third test for anonymous inodes
selftests/filesystems: add second test for anonymous inodes
selftests/filesystems: add first test for anonymous inodes
anon_inode: raise SB_I_NODEV and SB_I_NOEXEC
pidfs: use anon_inode_setattr()
anon_inode: explicitly block ->setattr()
pidfs: use anon_inode_getattr()
anon_inode: use a proper mode internally
Link: https://lore.kernel.org/20250407-work-anon_inode-v1-0-53a44c20d44e@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
It isn't possible to execute anonymous inodes because they cannot be
opened in any way after they have been created. This includes execution:
execveat(fd_anon_inode, "", NULL, NULL, AT_EMPTY_PATH)
Anonymous inodes have inode->f_op set to no_open_fops which sets
no_open() which returns ENXIO. That means any call to do_dentry_open()
which is the endpoint of the do_open_execat() will fail. There's no
chance to execute an anonymous inode. Unless a given subsystem overrides
it ofc.
However, we should still harden this and raise SB_I_NODEV and
SB_I_NOEXEC on the superblock itself so that no one gets any creative
ideas.
Link: https://lore.kernel.org/20250407-work-anon_inode-v1-5-53a44c20d44e@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Cc: stable@vger.kernel.org # all LTS kernels
Signed-off-by: Christian Brauner <brauner@kernel.org>
It is currently possible to change the mode and owner of the single
anonymous inode in the kernel:
int main(int argc, char *argv[])
{
int ret, sfd;
sigset_t mask;
struct signalfd_siginfo fdsi;
sigemptyset(&mask);
sigaddset(&mask, SIGINT);
sigaddset(&mask, SIGQUIT);
ret = sigprocmask(SIG_BLOCK, &mask, NULL);
if (ret < 0)
_exit(1);
sfd = signalfd(-1, &mask, 0);
if (sfd < 0)
_exit(2);
ret = fchown(sfd, 5555, 5555);
if (ret < 0)
_exit(3);
ret = fchmod(sfd, 0777);
if (ret < 0)
_exit(3);
_exit(4);
}
This is a bug. It's not really a meaningful one because anonymous inodes
don't really figure into path lookup and they cannot be reopened via
/proc/<pid>/fd/<nr> and can't be used for lookup itself. So they can
only ever serve as direct references.
But it is still completely bogus to allow the mode and ownership or any
of the properties of the anonymous inode to be changed. Block this!
Link: https://lore.kernel.org/20250407-work-anon_inode-v1-3-53a44c20d44e@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Cc: stable@vger.kernel.org # all LTS kernels
Signed-off-by: Christian Brauner <brauner@kernel.org>
Update the document to reflect that initramfs didn't replace initrd
following kernel 2.5.x.
The initramfs buffer format now supports many compression types in
addition to gzip, so include them in the grammar section.
c_mtime use is dependent on CONFIG_INITRAMFS_PRESERVE_MTIME.
Signed-off-by: David Disseldorp <ddiss@suse.de>
Link: https://lore.kernel.org/r/20250402033949.852-2-ddiss@suse.de
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Pull soundwire fix from Vinod Koul:
- add missing config symbol CONFIG_SND_HDA_EXT_CORE required for asoc
driver CONFIG_SND_SOF_SOF_HDA_SDW_BPT
* tag 'soundwire-6.15-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/soundwire:
ASoC: SOF: Intel: Let SND_SOF_SOF_HDA_SDW_BPT select SND_HDA_EXT_CORE
Support up to 8192 processors
Add cpuidle governor debug telemetry, disabled by default
Update default output to exclude cpuidle invocation counts
Bug fixes
Signed-off-by: Len Brown <len.brown@intel.com>
Create "pct_idle" counter group, the sofware notion of residency
so it can now be singled out, independent of other counter groups.
Create "cpuidle" group, the cpuidle invocation counts.
Disable "cpuidle", by default.
Create "swidle" = "cpuidle" + "pct_idle".
Undocument "sysfs", the old name for "swidle", but keep it working
for backwards compatibilty.
Create "hwidle", all the HW idle counters
Modify "idle", enabled by default
"idle" = "hwidle" + "pct_idle" (and now excludes "cpuidle")
Signed-off-by: Len Brown <len.brown@intel.com>
Pull perf event fix from Ingo Molnar:
"Fix a perf events time accounting bug"
* tag 'perf-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix child_total_time_enabled accounting bug at task exit
Pull scheduler fixes from Ingo Molnar:
- Fix a nonsensical Kconfig combination
- Remove an unnecessary rseq-notification
* tag 'sched-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rseq: Eliminate useless task_work on execve
sched/isolation: Make CONFIG_CPU_ISOLATION depend on CONFIG_SMP
... and don't error out so hard on missing module descriptions.
Before commit 6c6c1fc09d ("modpost: require a MODULE_DESCRIPTION()")
we used to warn about missing module descriptions, but only when
building with extra warnigns (ie 'W=1').
After that commit the warning became an unconditional hard error.
And it turns out not all modules have been converted despite the claims
to the contrary. As reported by Damian Tometzki, the slub KUnit test
didn't have a module description, and apparently nobody ever really
noticed.
The reason nobody noticed seems to be that the slub KUnit tests get
disabled by SLUB_TINY, which also ends up disabling a lot of other code,
both in tests and in slub itself. And so anybody doing full build tests
didn't actually see this failre.
So let's disable SLUB_TINY for build-only tests, since it clearly ends
up limiting build coverage. Also turn the missing module descriptions
error back into a warning, but let's keep it around for non-'W=1'
builds.
Reported-by: Damian Tometzki <damian@riscv-rocks.de>
Link: https://lore.kernel.org/all/01070196099fd059-e8463438-7b1b-4ec8-816d-173874be9966-000000@eu-central-1.amazonses.com/
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Fixes: 6c6c1fc09d ("modpost: require a MODULE_DESCRIPTION()")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Probe cpuidle "sysfs" residency and counts separately,
since soon we will make one disabled on, and the
other disabled off.
Clarify that some BIC (build-in-counters) are actually "groups".
since we're about to re-name some of those groups.
no functional change.
Signed-off-by: Len Brown <len.brown@intel.com>
Do fflush() to discard the buffered data, before each read of the
graphics sysfs knobs.
Fixes: ba99a4fc8c ("tools/power turbostat: Remove unnecessary fflush() call")
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Document that on Intel Granite Rapids Systems,
Uncore domains 0-2 are CPU domains, and
uncore domains 3-4 are IO domains.
Signed-off-by: Len Brown <len.brown@intel.com>
The CoreThr column displays total thermal throttling events
since boot time.
Change it to report events during the measurement interval.
This is more useful for showing a user the current conditions.
Total events since boot time are still available to the user via
/sys/devices/system/cpu/cpu*/thermal_throttle/*
Document CoreThr on turbostat.8
Fixes: eae97e053f ("turbostat: Support thermal throttle count print")
Reported-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: Chen Yu <yu.c.chen@intel.com>
On systems with >= 1024 cpus (in my case 1152), turbostat fails with the error output:
"turbostat: /sys/fs/cgroup/cpuset.cpus.effective: cpu str malformat 0-1151"
A similar error appears with the use of turbostat --cpu when the inputted cpu
range contains a cpu number >= 1024:
# turbostat -c 1100-1151
"--cpu 1100-1151" malformed
...
Both errors are caused by parse_cpu_str() reaching its limit of CPU_SUBSET_MAXCPUS.
It's a good idea to limit the maximum cpu number being parsed, but 1024 is too low.
For a small increase in compute and allocated memory, increasing CPU_SUBSET_MAXCPUS
brings support for parsing cpu numbers >= 1024.
Increase CPU_SUBSET_MAXCPUS to 8192, a common setting for CONFIG_NR_CPUS on x86_64.
Signed-off-by: Justin Ernst <justin.ernst@hpe.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Pull timer cleanups from Thomas Gleixner:
"A set of final cleanups for the timer subsystem:
- Convert all del_timer[_sync]() instances over to the new
timer_delete[_sync]() API and remove the legacy wrappers.
Conversion was done with coccinelle plus some manual fixups as
coccinelle chokes on scoped_guard().
- The final cleanup of the hrtimer_init() to hrtimer_setup()
conversion.
This has been delayed to the end of the merge window, so that all
patches which have been merged through other trees are in mainline
and all new users are catched.
Doing this right before rc1 ensures that new code which is merged post
rc1 is not introducing new instances of the original functionality"
* tag 'timers-cleanups-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tracing/timers: Rename the hrtimer_init event to hrtimer_setup
hrtimers: Rename debug_init_on_stack() to debug_setup_on_stack()
hrtimers: Rename debug_init() to debug_setup()
hrtimers: Rename __hrtimer_init_sleeper() to __hrtimer_setup_sleeper()
hrtimers: Remove unnecessary NULL check in hrtimer_start_range_ns()
hrtimers: Make callback function pointer private
hrtimers: Merge __hrtimer_init() into __hrtimer_setup()
hrtimers: Switch to use __htimer_setup()
hrtimers: Delete hrtimer_init()
treewide: Convert new and leftover hrtimer_init() users
treewide: Switch/rename to timer_delete[_sync]()
Pull more irq updates from Thomas Gleixner:
"A set of updates for the interrupt subsystem:
- A treewide cleanup for the irq_domain code, which makes the naming
consistent and gets rid of the original oddity of naming domains
'host'.
This is a trivial mechanical change and is done late to ensure that
all instances have been catched and new code merged post rc1 wont
reintroduce new instances.
- A trivial consistency fix in the migration code
The recent introduction of irq_force_complete_move() in the core
code, causes a problem for the nostalgia crowd who maintains ia64
out of tree.
The code assumes that hierarchical interrupt domains are enabled
and dereferences irq_data::parent_data unconditionally. That works
in mainline because both architectures which enable that code have
hierarchical domains enabled. Though it breaks the ia64 build,
which enables the functionality, but does not have hierarchical
domains.
While it's not really a problem for mainline today, this
unconditional dereference is inconsistent and trivially fixable by
using the existing helper function irqd_get_parent_data(), which
has the appropriate #ifdeffery in place"
* tag 'irq-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/migration: Use irqd_get_parent_data() in irq_force_complete_move()
irqdomain: Stop using 'host' for domain
irqdomain: Rename irq_get_default_host() to irq_get_default_domain()
irqdomain: Rename irq_set_default_host() to irq_set_default_domain()