Commit Graph

1351140 Commits

Author SHA1 Message Date
David Howells
db26d62d79 netfs: Fix undifferentiation of DIO reads from unbuffered reads
On cifs, "DIO reads" (specified by O_DIRECT) need to be differentiated from
"unbuffered reads" (specified by cache=none in the mount parameters).  The
difference is flagged in the protocol and the server may behave
differently: Windows Server will, for example, mandate that DIO reads are
block aligned.

Fix this by adding a NETFS_UNBUFFERED_READ to differentiate this from
NETFS_DIO_READ, parallelling the write differentiation that already exists.
cifs will then do the right thing.

Fixes: 016dc8516a ("netfs: Implement unbuffered/DIO read support")
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/3444961.1747987072@warthog.procyon.org.uk
Reviewed-by: "Paulo Alcantara (Red Hat)" <pc@manguebit.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
cc: Steve French <sfrench@samba.org>
cc: netfs@lists.linux.dev
cc: v9fs@lists.linux.dev
cc: linux-afs@lists.infradead.org
cc: linux-cifs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-05-23 10:35:03 +02:00
Christian Brauner
5fddfbc0cb Merge patch series "netfs: Miscellaneous fixes"
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>
2025-05-21 14:35:34 +02:00
David Howells
2b1424cd13 netfs: Fix wait/wake to be consistent about the waitqueue used
Fix further inconsistencies in the use of waitqueues
(clear_and_wake_up_bit() vs private waitqueue).

Move some of this stuff from the read and write sides into common code so
that it can be done in fewer places.

To make this work, async I/O needs to set NETFS_RREQ_OFFLOAD_COLLECTION to
indicate that a workqueue will do the collecting and places that call the
wait function need to deal with it returning the amount transferred.

Fixes: e2d46f2ec3 ("netfs: Change the read result collector to only use one work item")
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519090707.2848510-5-dhowells@redhat.com
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Steve French <stfrench@microsoft.com>
cc: Ihor Solodrai <ihor.solodrai@pm.me>
cc: Eric Van Hensbergen <ericvh@kernel.org>
cc: Latchesar Ionkov <lucho@ionkov.net>
cc: Dominique Martinet <asmadeus@codewreck.org>
cc: Christian Schoenebeck <linux_oss@crudebyte.com>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: v9fs@lists.linux.dev
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>
2025-05-21 14:35:21 +02:00
David Howells
20d72b00ca netfs: Fix the request's work item to not require a ref
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>
2025-05-21 14:35:20 +02:00
Paulo Alcantara
34eb98c659 netfs: Fix setting of transferred bytes with short DIO reads
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>
2025-05-21 14:35:20 +02:00
David Howells
4481f7f2b3 netfs: Fix oops in write-retry from mis-resetting the subreq iterator
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>
2025-05-21 14:35:20 +02:00
Christian Brauner
e02cdc0e7f Merge patch series "netfs: Miscellaneous cleanups"
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>
2025-05-21 14:34:43 +02:00
Max Kellermann
4b1ca12dd3 fs/netfs: remove unused flag NETFS_RREQ_BLOCKED
NETFS_RREQ_BLOCKED was added by commit 016dc8516a ("netfs: Implement
unbuffered/DIO read support") but has never been used either.  Without
NETFS_RREQ_BLOCKED, NETFS_RREQ_NONBLOCK makes no sense, and thus can
be removed as well.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519134813.2975312-12-dhowells@redhat.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>
2025-05-21 14:34:38 +02:00
Max Kellermann
67b916719a fs/netfs: remove unused flag NETFS_RREQ_DONT_UNLOCK_FOLIOS
NETFS_RREQ_DONT_UNLOCK_FOLIOS has never been used ever since it was
added by commit 3d3c950467 ("netfs: Provide readahead and readpage
netfs helpers").

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519134813.2975312-11-dhowells@redhat.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>
2025-05-21 14:34:38 +02:00
Max Kellermann
6bb09e5db3 folio_queue: remove unused field marks3
The last user was removed by commit e2d46f2ec3 ("netfs: Change the
read result collector to only use one work item").

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519134813.2975312-10-dhowells@redhat.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>
2025-05-21 14:34:38 +02:00
Max Kellermann
07c08bac93 fs/netfs: declare field proc_link only if CONFIG_PROC_FS=y
This field is only used for the "proc" filesystem.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519134813.2975312-9-dhowells@redhat.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>
2025-05-21 14:34:38 +02:00
Max Kellermann
3dc00bca8d fs/netfs: remove netfs_io_request.ractl
Since this field is only used by netfs_prepare_read_iterator() when
called by netfs_readahead(), we can simply pass it as parameter.  This
shrinks the struct from 576 to 568 bytes.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519134813.2975312-8-dhowells@redhat.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>
2025-05-21 14:34:38 +02:00
Max Kellermann
314ee7035f fs/netfs: reorder struct fields to eliminate holes
This shrinks `struct netfs_io_stream` from 104 to 96 bytes and `struct
netfs_io_request` from 600 to 576 bytes.

[DH: Modified as the patch to turn netfs_io_request::error into a short
was removed from the set]

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519134813.2975312-7-dhowells@redhat.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>
2025-05-21 14:34:37 +02:00
Max Kellermann
d46a7b217d fs/netfs: remove unused enum choice NETFS_READ_HOLE_CLEAR
This choice was added by commit 3a11b3a863 ("netfs: Pass more
information on how to deal with a hole in the cache") but the last
user was removed by commit 86b374d061 ("netfs: Remove
fs/netfs/io.c").

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519134813.2975312-6-dhowells@redhat.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>
2025-05-21 14:34:37 +02:00
Max Kellermann
9fcf235e91 fs/netfs: remove unused flag NETFS_ICTX_WRITETHROUGH
This flag was added by commit 41d8e7673a ("netfs: Implement a
write-through caching option") but it was never used.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519134813.2975312-5-dhowells@redhat.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>
2025-05-21 14:34:37 +02:00
Max Kellermann
9cd78ca04f fs/netfs: remove unused source NETFS_INVALID_WRITE
This enum choice was added by commit 16af134ca4 ("netfs: Extend the
netfs_io_*request structs to handle writes") and its only user was
later removed by commit c245868524 ("netfs: Remove the old writeback
code").

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519134813.2975312-4-dhowells@redhat.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>
2025-05-21 14:34:37 +02:00
Max Kellermann
c1a606cd75 fs/netfs: remove unused flag NETFS_SREQ_SEEK_DATA_READ
This flag was added by commit 3d3c950467 ("netfs: Provide readahead
and readpage netfs helpers") but its only user was removed by commit
86b374d061 ("netfs: Remove fs/netfs/io.c").

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/20250519134813.2975312-3-dhowells@redhat.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>
2025-05-21 14:34:37 +02:00
Christian Brauner
a1b4a25abb Merge netfs API documentation updates
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>
2025-05-21 14:30:48 +02:00
David Howells
f1745496d3 netfs: Update main API document
Bring the netfs documentation up to date.

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/1690127.1744208325@warthog.procyon.org.uk
Reviewed-by: "Paulo Alcantara (Red Hat)" <pc@manguebit.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: Viacheslav Dubeyko <slava@dubeyko.com>
cc: Alex Markuze <amarkuze@redhat.com>
cc: Timothy Day <timday@amazon.com>
cc: Jonathan Corbet <corbet@lwn.net>
cc: netfs@lists.linux.dev
cc: linux-doc@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-11 15:23:50 +02:00
Mateusz Guzik
e45960c279 fs: unconditionally use atime_needs_update() in pick_link()
Vast majority of the time the func returns false.

This avoids a branch to determine whether we are in RCU mode.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/20250408073641.1799151-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-08 11:08:24 +02:00
Christian Brauner
c9b380a017 Merge patch series "fs: sort out cosmetic differences between stat funcs and add predicts"
Predict fastpaths in stat and during fdput().

* patches from https://lore.kernel.org/20250406235806.1637000-1-mjguzik@gmail.com:
  fs: predict not having to do anything in fdput()
  fs: sort out cosmetic differences between stat funcs and add predicts

Link: https://lore.kernel.org/20250406235806.1637000-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-08 10:28:10 +02:00
Mateusz Guzik
5f3e0b4a1f fs: predict not having to do anything in fdput()
This matches the annotation in fdget().

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/20250406235806.1637000-2-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-08 10:28:07 +02:00
Mateusz Guzik
eaec2cd167 fs: sort out cosmetic differences between stat funcs and add predicts
This is a nop, but I did verify asm improves.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/20250406235806.1637000-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-08 10:28:07 +02:00
Christian Brauner
9d36c5145a Merge patch series "fs: harden anon inodes"
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>
2025-04-07 16:20:15 +02:00
Christian Brauner
25a6cc9a63 selftests/filesystems: add open() test for anonymous inodes
Test that anonymous inodes cannot be open()ed.

Link: https://lore.kernel.org/20250407-work-anon_inode-v1-9-53a44c20d44e@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-07 16:20:15 +02:00
Christian Brauner
f8ca403ae7 selftests/filesystems: add exec() test for anonymous inodes
Test that anonymous inodes cannot be exec()ed.

Link: https://lore.kernel.org/20250407-work-anon_inode-v1-8-53a44c20d44e@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-07 16:20:14 +02:00
Christian Brauner
fcf31ec7ca selftests/filesystems: add chmod() test for anonymous inodes
Test that anonymous inodes cannot be chmod()ed.

Link: https://lore.kernel.org/20250407-work-anon_inode-v1-7-53a44c20d44e@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-07 16:20:14 +02:00
Christian Brauner
c784159750 selftests/filesystems: add chown() test for anonymous inodes
Test that anonymous inodes cannot be chown()ed.

Link: https://lore.kernel.org/20250407-work-anon_inode-v1-6-53a44c20d44e@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-07 16:20:14 +02:00
Christian Brauner
1ed95281c0 anon_inode: raise SB_I_NODEV and SB_I_NOEXEC
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>
2025-04-07 16:19:04 +02:00
Christian Brauner
c83b902496 pidfs: use anon_inode_setattr()
So far pidfs did use it's own version. Just use the generic version.
We use our own wrappers because we're going to be implementing
properties soon.

Link: https://lore.kernel.org/20250407-work-anon_inode-v1-4-53a44c20d44e@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-07 16:19:02 +02:00
Christian Brauner
22bdf3d658 anon_inode: explicitly block ->setattr()
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>
2025-04-07 16:18:59 +02:00
Christian Brauner
37e62dafbf pidfs: use anon_inode_getattr()
So far pidfs did use it's own version. Just use the generic version. We
use our own wrappers because we're going to be implementing our own
retrieval properties soon.

Link: https://lore.kernel.org/20250407-work-anon_inode-v1-2-53a44c20d44e@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-07 16:18:56 +02:00
Christian Brauner
cfd86ef7e8 anon_inode: use a proper mode internally
This allows the VFS to not trip over anonymous inodes and we can add
asserts based on the mode into the vfs. When we report it to userspace
we can simply hide the mode to avoid regressions. I've audited all
direct callers of alloc_anon_inode() and only secretmen overrides i_mode
and i_op inode operations but it already uses a regular file.

Link: https://lore.kernel.org/20250407-work-anon_inode-v1-1-53a44c20d44e@kernel.org
Fixes: af153bb63a ("vfs: catch invalid modes in may_open()")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Cc: stable@vger.kernel.org # all LTS kernels
Reported-by: syzbot+5d8e79d323a13aa0b248@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/67ed3fb3.050a0220.14623d.0009.GAE@google.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-07 16:18:46 +02:00
David Disseldorp
418556fa57 docs: initramfs: update compression and mtime descriptions
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>
2025-04-07 09:38:01 +02:00
Linus Torvalds
0af2f6be1b Linux 6.15-rc1 v6.15-rc1 2025-04-06 13:11:33 -07:00
Thomas Weißschuh
0efdedb335 tools/include: make uapi/linux/types.h usable from assembly
The "real" linux/types.h UAPI header gracefully degrades to a NOOP when
included from assembly code.

Mirror this behaviour in the tools/ variant.

Test for __ASSEMBLER__ over __ASSEMBLY__ as the former is provided by the
toolchain automatically.

Reported-by: Mark Brown <broonie@kernel.org>
Closes: https://lore.kernel.org/lkml/af553c62-ca2f-4956-932c-dd6e3a126f58@sirena.org.uk/
Fixes: c9fbaa8795 ("selftests: vDSO: parse_vdso: Use UAPI headers instead of libc headers")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20250321-uapi-consistency-v1-1-439070118dc0@linutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2025-04-06 12:55:31 -07:00
Linus Torvalds
710329254d Merge tag 'turbostat-2025.05.06' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux
Pull turbostat updates from Len Brown:

 - support up to 8192 processors

 - add cpuidle governor debug telemetry, disabled by default

 - update default output to exclude cpuidle invocation counts

 - bug fixes

* tag 'turbostat-2025.05.06' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
  tools/power turbostat: v2025.05.06
  tools/power turbostat: disable "cpuidle" invocation counters, by default
  tools/power turbostat: re-factor sysfs code
  tools/power turbostat: Restore GFX sysfs fflush() call
  tools/power turbostat: Document GNR UncMHz domain convention
  tools/power turbostat: report CoreThr per measurement interval
  tools/power turbostat: Increase CPU_SUBSET_MAXCPUS to 8192
  tools/power turbostat: Add idle governor statistics reporting
  tools/power turbostat: Fix names matching
  tools/power turbostat: Allow Zero return value for some RAPL registers
  tools/power turbostat: Clustered Uncore MHz counters should honor show/hide options
2025-04-06 12:32:43 -07:00
Linus Torvalds
59f392fa7c Merge tag 'soundwire-6.15-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/soundwire
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
2025-04-06 12:04:53 -07:00
Len Brown
03e00e373c tools/power turbostat: v2025.05.06
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>
2025-04-06 14:49:20 -04:00
Len Brown
ec4acd3166 tools/power turbostat: disable "cpuidle" invocation counters, by default
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>
2025-04-06 14:29:57 -04:00
Linus Torvalds
dda8887894 Merge tag 'perf-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
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
2025-04-06 10:48:12 -07:00
Linus Torvalds
302deb109d Merge tag 'sched-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
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
2025-04-06 10:44:58 -07:00
Linus Torvalds
6f110a5e4f Disable SLUB_TINY for build testing
... 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>
2025-04-06 10:00:04 -07:00
Len Brown
994633894f tools/power turbostat: re-factor sysfs code
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>
2025-04-06 12:53:18 -04:00
Zhang Rui
f8b136ef26 tools/power turbostat: Restore GFX sysfs fflush() call
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>
2025-04-06 12:36:03 -04:00
Len Brown
3ae8508663 tools/power turbostat: Document GNR UncMHz domain convention
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>
2025-04-06 12:31:59 -04:00
Len Brown
f729775f79 tools/power turbostat: report CoreThr per measurement interval
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>
2025-04-06 12:21:25 -04:00
Justin Ernst
eb187540d1 tools/power turbostat: Increase CPU_SUBSET_MAXCPUS to 8192
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>
2025-04-06 12:14:14 -04:00
Linus Torvalds
16cd1c2657 Merge tag 'timers-cleanups-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
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]()
2025-04-06 08:35:37 -07:00
Linus Torvalds
ff0c66685d Merge tag 'irq-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
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()
2025-04-06 08:17:43 -07:00