Commit Graph

1310320 Commits

Author SHA1 Message Date
Yishai Hadas
22e87bf3f7 vfio/mlx5: Fix an unwind issue in mlx5vf_add_migration_pages()
Fix an unwind issue in mlx5vf_add_migration_pages().

If a set of pages is allocated but fails to be added to the SG table,
they need to be freed to prevent a memory leak.

Any pages successfully added to the SG table will be freed as part of
mlx5vf_free_data_buffer().

Fixes: 6fadb02126 ("vfio/mlx5: Implement vfio_pci driver for mlx5 devices")
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20241114095318.16556-2-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-11-14 11:42:17 -07:00
Yishai Hadas
40bcdb12c6 vfio/virtio: Enable live migration once VIRTIO_PCI was configured
Now that the driver supports live migration, only the legacy IO
functionality depends on config VIRTIO_PCI_ADMIN_LEGACY.

As part of that we introduce a bool configuration option as a sub menu
under the driver's main live migration feature named
VIRTIO_VFIO_PCI_ADMIN_LEGACY, to control the legacy IO functionality.

This will let users configuring the kernel, know which features from the
description might be available in the resulting driver.

As of that, move the legacy IO into a separate file to be compiled only
once CONFIG_VIRTIO_VFIO_PCI_ADMIN_LEGACY was configured and let the live
migration depends only on VIRTIO_PCI.

Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20241113115200.209269-8-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-11-13 16:28:32 -07:00
Yishai Hadas
6cea64b1db vfio/virtio: Add PRE_COPY support for live migration
Add PRE_COPY support for live migration.

This functionality may reduce the downtime upon STOP_COPY as of letting
the target machine to get some 'initial data' from the source once the
machine is still in its RUNNING state and let it prepares itself
pre-ahead to get the final STOP_COPY data.

As the Virtio specification does not support reading partial or
incremental device contexts. This means that during the PRE_COPY state,
the vfio-virtio driver reads the full device state.

As the device state can be changed and the benefit is highest when the
pre copy data closely matches the final data we read it in a rate
limiter mode.

This means we avoid reading new data from the device for a specified
time interval after the last read.

With PRE_COPY enabled, we observed a downtime reduction of approximately
70-75% in various scenarios compared to when PRE_COPY was disabled,
while keeping the total migration time nearly the same.

Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20241113115200.209269-7-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-11-13 16:28:32 -07:00
Yishai Hadas
0bbc82e4ec vfio/virtio: Add support for the basic live migration functionality
Add support for basic live migration functionality in VFIO over
virtio-net devices, aligned with the virtio device specification 1.4.

This includes the following VFIO features:
VFIO_MIGRATION_STOP_COPY, VFIO_MIGRATION_P2P.

The implementation registers with the VFIO subsystem using vfio_pci_core
and then incorporates the virtio-specific logic for the migration
process.

The migration follows the definitions in uapi/vfio.h and leverages the
virtio VF-to-PF admin queue command channel for execution device parts
related commands.

Additional Notes:
-----------------
The kernel protocol between the source and target devices contains a
header with metadata, including record size, tag, and flags.

The record size allows the target to recognize and read a complete image
from the source before passing the device part data. This adheres to the
virtio device specification, which mandates that partial device parts
cannot be supplied.

The tag and flags serve as placeholders for future extensions of the
kernel protocol between the source and target, ensuring backward and
forward compatibility.

Both the source and target comply with the virtio device specification
by using a device part object with a unique ID as part of the migration
process. Since this resource is limited to a maximum of 255, its
lifecycle is confined to periods with an active live migration flow.

According to the virtio specification, a device has only two modes:
RUNNING and STOPPED. As a result, certain VFIO transitions (i.e.,
RUNNING_P2P->STOP, STOP->RUNNING_P2P) are treated as no-ops. When
transitioning to RUNNING_P2P, the device state is set to STOP, and it
will remain STOPPED until the transition out of RUNNING_P2P->RUNNING, at
which point it returns to RUNNING. During transition to STOP, the virtio
device only stops initiating outgoing requests(e.g. DMA, MSIx, etc.) but
still must accept incoming operations.

Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20241113115200.209269-6-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-11-13 16:26:57 -07:00
Yishai Hadas
52a22c0ed0 virtio-pci: Introduce APIs to execute device parts admin commands
Introduce APIs to handle the execution of device parts admin commands.

These APIs cover functionalities such as mode setting, object creation
and destruction, and operations like parts get/set and metadata
retrieval.

These APIs will be utilized in upcoming patches within this series.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20241113115200.209269-5-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-11-13 15:25:41 -07:00
Yishai Hadas
bfcad51860 virtio: Manage device and driver capabilities via the admin commands
Manage device and driver capabilities via the admin commands.

The device exposes its supported features and resource object limits via
an administrative command called VIRTIO_ADMIN_CMD_CAP_ID_LIST_QUERY,
using the 'self group type.'

Each capability is identified by a unique ID, and the driver
communicates the functionality and resource limits it plans to utilize.

The capability VIRTIO_DEV_PARTS_CAP specifically represents the device's
parts resource object limit.

Manage the device's parts resource object ID using a common IDA for both
get and set operations.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20241113115200.209269-4-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-11-13 15:25:41 -07:00
Yishai Hadas
704806ca40 virtio: Extend the admin command to include the result size
Extend the admin command by incorporating a result size field.

This allows higher layers to determine the actual result size from the
backend when this information is not included in the result_sg.

The additional information introduced here will be used in subsequent
patches of this series.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20241113115200.209269-3-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-11-13 15:25:41 -07:00
Yishai Hadas
7c1ae151e8 virtio_pci: Introduce device parts access commands
Introduce device parts access commands via the admin queue.

These commands and their structure adhere to the Virtio 1.4
specification.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20241113115200.209269-2-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-11-13 15:25:41 -07:00
Longfang Liu
a13bf78fee Documentation: add debugfs description for hisi migration
Add a debugfs document description file to help users understand
how to use the hisilicon accelerator live migration driver's
debugfs.

Update the file paths that need to be maintained in MAINTAINERS

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20241112073322.54550-5-liulongfang@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-11-13 14:59:33 -07:00
Longfang Liu
b398f91779 hisi_acc_vfio_pci: register debugfs for hisilicon migration driver
On the debugfs framework of VFIO, if the CONFIG_VFIO_DEBUGFS macro is
enabled, the debug function is registered for the live migration driver
of the HiSilicon accelerator device.

After registering the HiSilicon accelerator device on the debugfs
framework of live migration of vfio, a directory file "hisi_acc"
of debugfs is created, and then three debug function files are
created in this directory:

   vfio
    |
    +---<dev_name1>
    |    +---migration
    |        +--state
    |        +--hisi_acc
    |            +--dev_data
    |            +--migf_data
    |            +--cmd_state
    |
    +---<dev_name2>
         +---migration
             +--state
             +--hisi_acc
                 +--dev_data
                 +--migf_data
                 +--cmd_state

dev_data file: read device data that needs to be migrated from the
current device in real time
migf_data file: read the migration data of the last live migration
from the current driver.
cmd_state: used to get the cmd channel state for the device.

+----------------+        +--------------+       +---------------+
| migration dev  |        |   src  dev   |       |   dst  dev    |
+-------+--------+        +------+-------+       +-------+-------+
        |                        |                       |
        |                 +------v-------+       +-------v-------+
        |                 |  saving_migf |       | resuming_migf |
  read  |                 |     file     |       |     file      |
        |                 +------+-------+       +-------+-------+
        |                        |          copy         |
        |                        +------------+----------+
        |                                     |
+-------v--------+                    +-------v--------+
|   data buffer  |                    |   debug_migf   |
+-------+--------+                    +-------+--------+
        |                                     |
   cat  |                                 cat |
+-------v--------+                    +-------v--------+
|   dev_data     |                    |   migf_data    |
+----------------+                    +----------------+

When accessing debugfs, user can obtain the most recent status data
of the device through the "dev_data" file. It can read recent
complete status data of the device. If the current device is being
migrated, it will wait for it to complete.
The data for the last completed migration function will be stored
in debug_migf. Users can read it via "migf_data".

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20241112073322.54550-4-liulongfang@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-11-13 14:58:47 -07:00
Longfang Liu
1962920689 hisi_acc_vfio_pci: create subfunction for data reading
This patch generates the code for the operation of reading data from
the device into a sub-function.
Then, it can be called during the device status data saving phase of
the live migration process and the device status data reading function
in debugfs.
Thereby reducing the redundant code of the driver.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20241112073322.54550-3-liulongfang@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-11-12 14:23:10 -07:00
Longfang Liu
ece8a2c77b hisi_acc_vfio_pci: extract public functions for container_of
In the current driver, vdev is obtained from struct
hisi_acc_vf_core_device through the container_of function.
This method is used in many places in the driver. In order to
reduce this repetitive operation, It was extracted into
a public function.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20241112073322.54550-2-liulongfang@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-11-12 14:23:10 -07:00
Giovanni Cabiddu
9283b73925 vfio/qat: fix overflow check in qat_vf_resume_write()
The unsigned variable `size_t len` is cast to the signed type `loff_t`
when passed to the function check_add_overflow(). This function considers
the type of the destination, which is of type loff_t (signed),
potentially leading to an overflow. This issue is similar to the one
described in the link below.

Remove the cast.

Note that even if check_add_overflow() is bypassed, by setting `len` to
a value that is greater than LONG_MAX (which is considered as a negative
value after the cast), the function copy_from_user(), invoked a few lines
later, will not perform any copy and return `len` as (len > INT_MAX)
causing qat_vf_resume_write() to fail with -EFAULT.

Fixes: bb208810b1 ("vfio/qat: Add vfio_pci driver for Intel QAT SR-IOV VF devices")
CC: stable@vger.kernel.org # 6.10+
Link: https://lore.kernel.org/all/138bd2e2-ede8-4bcc-aa7b-f3d9de167a37@moroto.mountain
Reported-by: Zijie Zhao <zzjas98@gmail.com>
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Reviewed-by: Xin Zeng <xin.zeng@intel.com>
Link: https://lore.kernel.org/r/20241021123843.42979-1-giovanni.cabiddu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-10-30 13:38:38 -06:00
Ankit Agrawal
12cd88a911 vfio/nvgrace-gpu: Add a new GH200 SKU to the devid table
NVIDIA is planning to productize a new Grace Hopper superchip
SKU with device ID 0x2348.

Add the SKU devid to nvgrace_gpu_vfio_pci_table.

Signed-off-by: Ankit Agrawal <ankita@nvidia.com>
Link: https://lore.kernel.org/r/20241013075216.19229-1-ankita@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-10-30 13:35:18 -06:00
Christophe JAILLET
bbee049d8e kvm/vfio: Constify struct kvm_device_ops
'struct kvm_device_ops' is not modified in this driver.

Constifying this structure moves some data to a read-only section, so
increases overall security, especially when the structure holds some
function pointers.

On a x86_64, with allmodconfig:
Before:
======
   text	   data	    bss	    dec	    hex	filename
   2605	    169	     16	   2790	    ae6	virt/kvm/vfio.o

After:
=====
   text	   data	    bss	    dec	    hex	filename
   2685	     89	     16	   2790	    ae6	virt/kvm/vfio.o

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/e7361a1bb7defbb0f7056b884e83f8d75ac9fe21.1727517084.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2024-10-30 13:31:26 -06:00
Linus Torvalds
8198375843 Linux 6.12-rc5 v6.12-rc5 2024-10-27 12:52:02 -10:00
Linus Torvalds
ea1fda89f5 Merge tag 'x86_urgent_for_v6.12_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:

 - Prevent a certain range of pages which get marked as hypervisor-only,
   to get allocated to a CoCo (SNP) guest which cannot use them and thus
   fail booting

 - Fix the microcode loader on AMD to pay attention to the stepping of a
   patch and to handle the case where a BIOS config option splits the
   machine into logical NUMA nodes per L3 cache slice

 - Disable LAM from being built by default due to security concerns

* tag 'x86_urgent_for_v6.12_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sev: Ensure that RMP table fixups are reserved
  x86/microcode/AMD: Split load_microcode_amd()
  x86/microcode/AMD: Pay attention to the stepping dynamically
  x86/lam: Disable ADDRESS_MASKING in most cases
2024-10-27 09:01:36 -10:00
Linus Torvalds
f69a1accfe Merge tag 'ftrace-v6.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ftrace fixes from Steven Rostedt:

 - Fix missing mutex unlock in error path of register_ftrace_graph()

   A previous fix added a return on an error path and forgot to unlock
   the mutex. Instead of dealing with error paths, use guard(mutex) as
   the mutex is just released at the exit of the function anyway. Other
   functions in this file should be updated with this, but that's a
   cleanup and not a fix.

 - Change cpuhp setup name to be consistent with other cpuhp states

   The same fix that the above patch fixes added a cpuhp_setup_state()
   call with the name of "fgraph_idle_init". I was informed that it
   should instead be something like: "fgraph:online". Update that too.

* tag 'ftrace-v6.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  fgraph: Change the name of cpuhp state to "fgraph:online"
  fgraph: Fix missing unlock in register_ftrace_graph()
2024-10-27 08:56:22 -10:00
Linus Torvalds
284a2f8996 Merge tag 'platform-drivers-x86-v6.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86
Pull x86 platform driver fixes from Hans de Goede:

 - Asus thermal profile fix, fixing performance issues on Lunar Lake

 - Intel PMC: one revert for a lockdep issue and one bugfix

 - Dell WMI: Ignore some WMI events on suspend/resume to silence warnings

* tag 'platform-drivers-x86-v6.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86:
  platform/x86: asus-wmi: Fix thermal profile initialization
  platform/x86: dell-wmi: Ignore suspend notifications
  platform/x86/intel/pmc: Fix pmc_core_iounmap to call iounmap for valid addresses
  platform/x86:intel/pmc: Revert "Enable the ACPI PM Timer to be turned off when suspended"
2024-10-27 08:40:33 -10:00
Linus Torvalds
7bec4657b0 Merge tag 'firewire-fixes-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394
Pull firewire fix from Takashi Sakamoto:
 "A single commit to resolve a regression existing in v6.11 or later.

  The change in 1394 OHCI driver in v6.11 kernel could cause general
  protection faults when rediscovering nodes in IEEE 1394 bus while
  holding a spin lock. Consequently, watchdog checks can report a hard
  lockup.

  Currently, this issue is observed primarily during the system resume
  phase when using an extra node with three ports or more is used.
  However, it could potentially occur in the other cases as well"

* tag 'firewire-fixes-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
  firewire: core: fix invalid port index for parent device
2024-10-27 08:36:01 -10:00
Linus Torvalds
75f8b2f526 Merge tag 'block-6.12-20241026' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:

 - Pull request for MD via Song fixing a few issues

 - Fix a wrong check in blk_rq_map_user_bvec(), causing IO errors on
   passthrough IO (Xinyu)

* tag 'block-6.12-20241026' of git://git.kernel.dk/linux:
  block: fix sanity checks in blk_rq_map_user_bvec
  md/raid10: fix null ptr dereference in raid10_size()
  md: ensure child flush IO does not affect origin bio->bi_status
2024-10-27 08:29:36 -10:00
Linus Torvalds
a8b3be2617 Merge tag 'xfs-6.12-fixes-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fixes from Carlos Maiolino:

 - Fix recovery of allocator ops after a growfs

 - Do not fail repairs on metadata files with no attr fork

* tag 'xfs-6.12-fixes-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: update the pag for the last AG at recovery time
  xfs: don't use __GFP_RETRY_MAYFAIL in xfs_initialize_perag
  xfs: error out when a superblock buffer update reduces the agcount
  xfs: update the file system geometry after recoverying superblock buffers
  xfs: merge the perag freeing helpers
  xfs: pass the exact range to initialize to xfs_initialize_perag
  xfs: don't fail repairs on metadata files with no attr fork
2024-10-27 08:23:49 -10:00
Takashi Sakamoto
f6a6780e0b firewire: core: fix invalid port index for parent device
In a commit 24b7f8e5cd ("firewire: core: use helper functions for self
ID sequence"), the enumeration over self ID sequence was refactored with
some helper functions with KUnit tests. These helper functions are
guaranteed to work expectedly by the KUnit tests, however their application
includes a mistake to assign invalid value to the index of port connected
to parent device.

This bug affects the case that any extra node devices which has three or
more ports are connected to 1394 OHCI controller. In the case, the path
to update the tree cache could hits WARN_ON(), and gets general protection
fault due to the access to invalid address computed by the invalid value.

This commit fixes the bug to assign correct port index.

Cc: stable@vger.kernel.org
Reported-by: Edmund Raile <edmund.raile@proton.me>
Closes: https://lore.kernel.org/lkml/8a9902a4ece9329af1e1e42f5fea76861f0bf0e8.camel@proton.me/
Fixes: 24b7f8e5cd ("firewire: core: use helper functions for self ID sequence")
Link: https://lore.kernel.org/r/20241025034137.99317-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
2024-10-27 11:14:35 +09:00
Armin Wolf
b012170fed platform/x86: asus-wmi: Fix thermal profile initialization
When support for vivobook fan profiles was added, the initial
call to throttle_thermal_policy_set_default() was removed, which
however is necessary for full initialization.

Fix this by calling throttle_thermal_policy_set_default() again
when setting up the platform profile.

Fixes: bcbfcebda2 ("platform/x86: asus-wmi: add support for vivobook fan profiles")
Reported-by: Michael Larabel <Michael@phoronix.com>
Closes: https://www.phoronix.com/review/lunar-lake-xe2/5
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20241025191514.15032-2-W_Armin@gmx.de
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2024-10-26 13:03:10 +02:00
Linus Torvalds
850925a813 Merge tag '9p-for-6.12-rc5' of https://github.com/martinetd/linux
Pull more 9p reverts from Dominique Martinet:
 "Revert patches causing inode collision problems.

  The code simplification introduced significant regressions on servers
  that do not remap inode numbers when exporting multiple underlying
  filesystems with colliding inodes. See the top-most revert (commit
  be2ca38253) for details.

  This problem had been ignored for too long and the reverts will also
  head to stable (6.9+).

  I'm confident this set of patches gets us back to previous behaviour
  (another related patch had already been reverted back in April and
  we're almost back to square 1, and the rest didn't touch inode
  lifecycle)"

* tag '9p-for-6.12-rc5' of https://github.com/martinetd/linux:
  Revert "fs/9p: simplify iget to remove unnecessary paths"
  Revert "fs/9p: fix uaf in in v9fs_stat2inode_dotl"
  Revert "fs/9p: remove redundant pointer v9ses"
  Revert " fs/9p: mitigate inode collisions"
2024-10-25 15:25:02 -07:00
Linus Torvalds
c71f8fb4dc Merge tag 'v6.12-rc4-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull smb client fixes from Steve French:

 - Fix init module error caseb

 - Fix memory allocation error path (for passwords) in mount

* tag 'v6.12-rc4-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix warning when destroy 'cifs_io_request_pool'
  smb: client: Handle kstrdup failures for passwords
2024-10-25 11:45:22 -07:00
Linus Torvalds
81dcc79758 Merge tag 'fuse-fixes-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fixes from Miklos Szeredi:

 - Fix cached size after passthrough writes

   This fix needed a trivial change in the backing-file API, which
   resulted in some non-fuse files being touched.

 - Revert a commit meant as a cleanup but which triggered a WARNING

 - Remove a stray debug line left-over

* tag 'fuse-fixes-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: remove stray debug line
  Revert "fuse: move initialization of fuse_file to fuse_writepages() instead of in callback"
  fuse: update inode size after extending passthrough write
  fs: pass offset and result to backing_file end_write() callback
2024-10-25 11:41:18 -07:00
Linus Torvalds
f647053312 Merge tag 'nfsd-6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux
Pull nfsd fixes from Chuck Lever:

 - Fix a couple of use-after-free bugs

* tag 'nfsd-6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  nfsd: cancel nfsd_shrinker_work using sync mode in nfs4_state_shutdown_net
  nfsd: fix race between laundromat and free_stateid
2024-10-25 11:38:15 -07:00
Linus Torvalds
b423f5a9a6 Merge tag 'acpi-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI fixes from Rafael Wysocki:
 "These fix an ACPI PRM (Platform Runtime Mechanism) issue and add two
  new DMI quirks, one for an ACPI IRQ override and one for lid switch
  detection:

   - Make acpi_parse_prmt() look for EFI_MEMORY_RUNTIME memory regions
     only to comply with the UEFI specification and make PRM use
     efi_guid_t instead of guid_t to avoid a compiler warning triggered
     by that change (Koba Ko, Dan Carpenter)

   - Add an ACPI IRQ override quirk for LG 16T90SP (Christian Heusel)

   - Add a lid switch detection quirk for Samsung Galaxy Book2 (Shubham
     Panwar)"

* tag 'acpi-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: PRM: Clean up guid type in struct prm_handler_info
  ACPI: button: Add DMI quirk for Samsung Galaxy Book2 to fix initial lid detection issue
  ACPI: resource: Add LG 16T90SP to irq1_level_low_skip_override[]
  ACPI: PRM: Find EFI_MEMORY_RUNTIME block for PRM handler and context
2024-10-25 11:04:34 -07:00
Linus Torvalds
8c76163fff Merge tag 'pm-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
 "Update cpufreq documentation to match the code after recent changes
  (Christian Loehle), fix a units conversion issue in the CPPC cpufreq
  driver (liwei), and fix an error check in the dtpm_devfreq power
  capping driver (Yuan Can)"

* tag 'pm-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: CPPC: fix perf_to_khz/khz_to_perf conversion exception
  powercap: dtpm_devfreq: Fix error check against dev_pm_qos_add_request()
  cpufreq: docs: Reflect latency changes in docs
2024-10-25 11:00:50 -07:00
Linus Torvalds
48005a5a74 Merge tag 'pci-v6.12-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
Pull pci fixes from Bjorn Helgaas:

 - Hold the rescan lock while adding devices to avoid race with
   concurrent pwrctl rescan that can lead to a crash (Bartosz
   Golaszewski)

 - Avoid binding pwrctl driver to QCom WCN wifi if the DT lacks the
   necessary PMU regulator descriptions (Bartosz Golaszewski)

* tag 'pci-v6.12-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
  PCI/pwrctl: Abandon QCom WCN probe on pre-pwrseq device-trees
  PCI: Hold rescan lock while adding devices during host probe
2024-10-25 10:56:06 -07:00
Linus Torvalds
86d6688e60 Merge tag 'fbdev-for-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev
Pull fbdev fixes from Helge Deller:

 - Fix some build warnings and failures with CONFIG_FB_IOMEM_FOPS and
   CONFIG_FB_DEVICE

 - Remove the da8xx fbdev driver

 - Constify struct sbus_mmap_map and fix indentation warning

* tag 'fbdev-for-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev:
  fbdev: wm8505fb: select CONFIG_FB_IOMEM_FOPS
  fbdev: da8xx: remove the driver
  fbdev: Constify struct sbus_mmap_map
  fbdev: nvidiafb: fix inconsistent indentation warning
  fbdev: sstfb: Make CONFIG_FB_DEVICE optional
2024-10-25 10:51:58 -07:00
Linus Torvalds
f0560f974e Merge tag 'gpio-fixes-for-v6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux
Pull gpio fix from Bartosz Golaszewski:
 "Update MAINTAINERS with a keyword pattern for legacy GPIO API

  The goal is to alert us to anyone trying to use the deprecated, legacy
  API (this happens almost every release)"

* tag 'gpio-fixes-for-v6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
  MAINTAINERS: add a keyword entry for the GPIO subsystem
2024-10-25 10:47:51 -07:00
Linus Torvalds
7a7aecd9c0 Merge tag 'ata-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux
Pull ata fix from Niklas Cassel:

 - Fix the handling of ATA commands that timeout (command that did not
   receive a completion interrupt within the configured timeout time).

   Commands that timeout, while also having either the FAILFAST flag
   set, or the command being a passthrough command, should never be
   retried. Restore this behavior (as it was before v6.12-rc1).

* tag 'ata-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux:
  ata: libata: Set DID_TIME_OUT for commands that actually timed out
2024-10-25 10:42:29 -07:00
Linus Torvalds
01154cc30e Merge tag 'sound-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
 "The majority of changes here are about ASoC.

  There are two core changes in ASoC (the bump of minimal topology ABI
  version and the fix for references of components in DAPM code), and
  others are mostly various device-specific fixes for SoundWire, AMD,
  Intel, SOF, Qualcomm and FSL, in addition to a few usual HD-audio
  quirks and fixes"

* tag 'sound-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (33 commits)
  ALSA: hda/realtek: Update default depop procedure
  ASoC: qcom: sc7280: Fix missing Soundwire runtime stream alloc
  ASoC: fsl_micfil: Add sample rate constraint
  ASoC: rt722-sdca: increase clk_stop_timeout to fix clock stop issue
  ALSA: hda/tas2781: select CRC32 instead of CRC32_SARWATE
  ALSA: hda/realtek: Add subwoofer quirk for Acer Predator G9-593
  ALSA: firewire-lib: Avoid division by zero in apply_constraint_to_size()
  ASoC: fsl_micfil: Add a flag to distinguish with different volume control types
  ASoC: codecs: lpass-rx-macro: fix RXn(rx,n) macro for DSM_CTL and SEC7 regs
  ASoC: Change my e-mail to gmail
  ASoC: Intel: soc-acpi: lnl: Add match entry for TM2 laptops
  ASoC: amd: yc: Fix non-functional mic on ASUS E1404FA
  ASoC: SOF: Intel: hda: Always clean up link DMA during stop
  soundwire: intel_ace2x: Send PDI stream number during prepare
  ASoC: SOF: Intel: hda: Handle prepare without close for non-HDA DAI's
  ASoC: SOF: ipc4-topology: Do not set ALH node_id for aggregated DAIs
  MAINTAINERS: Update maintainer list for MICROCHIP ASOC, SSC and MCP16502 drivers
  ASoC: qcom: Select missing common Soundwire module code on SDM845
  ASoC: fsl_esai: change dev_warn to dev_dbg in irq handler
  ASoC: rsnd: Fix probe failure on HiHope boards due to endpoint parsing
  ...
2024-10-25 10:35:29 -07:00
Linus Torvalds
fd143856b0 Merge tag 'drm-fixes-2024-10-25' of https://gitlab.freedesktop.org/drm/kernel
Pull drm fixes from Dave Airlie:
 "Weekly drm fixes, mostly amdgpu and xe, with minor bridge and an i915
  Kconfig fix. Nothing too scary and it seems to be pretty quiet.

  amdgpu:
   - ACPI method handling fixes
   - SMU 14.x fixes
   - Display idle optimization fix
   - DP link layer compliance fix
   - SDMA 7.x fix
   - PSR-SU fix
   - SWSMU fix

  i915:
   - Fix DRM_I915_GVT_KVMGT dependencies in Kconfig

  xe:
   - Increase invalidation timeout to avoid errors in some hosts
   - Flush worker on timeout
   - Better handling for force wake failure
   - Improve argument check on user fence creation
   - Don't restart parallel queues multiple times on GT reset

  bridge:
   - aux: Fix assignment of OF node
   - tc358767: Add missing of_node_put() in error path"

* tag 'drm-fixes-2024-10-25' of https://gitlab.freedesktop.org/drm/kernel:
  drm/xe: Don't restart parallel queues multiple times on GT reset
  drm/xe/ufence: Prefetch ufence addr to catch bogus address
  drm/xe: Handle unreliable MMIO reads during forcewake
  drm/xe/guc/ct: Flush g2h worker in case of g2h response timeout
  drm/xe: Enlarge the invalidation timeout from 150 to 500
  drm/amdgpu: handle default profile on on devices without fullscreen 3D
  drm/amd/display: Disable PSR-SU on Parade 08-01 TCON too
  drm/amdgpu: fix random data corruption for sdma 7
  drm/amd/display: temp w/a for DP Link Layer compliance
  drm/amd/display: temp w/a for dGPU to enter idle optimizations
  drm/amd/pm: update deep sleep status on smu v14.0.2/3
  drm/amd/pm: update overdrive function on smu v14.0.2/3
  drm/amd/pm: update the driver-fw interface file for smu v14.0.2/3
  drm/amd: Guard against bad data for ATIF ACPI method
  drm/bridge: tc358767: fix missing of_node_put() in for_each_endpoint_of_node()
  drm/bridge: Fix assignment of the of_node of the parent to aux bridge
  i915: fix DRM_I915_GVT_KVMGT dependencies
2024-10-25 10:29:51 -07:00
Linus Torvalds
4dc1f31ec3 x86: fix whitespace in runtime-const assembler output
The x86 user pointer validation changes made me look at compiler output
a lot, and the wrong indentation for the ".popsection" in the generated
assembler triggered me.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-10-25 09:53:03 -07:00
Linus Torvalds
86e6b1547b x86: fix user address masking non-canonical speculation issue
It turns out that AMD has a "Meltdown Lite(tm)" issue with non-canonical
accesses in kernel space.  And so using just the high bit to decide
whether an access is in user space or kernel space ends up with the good
old "leak speculative data" if you have the right gadget using the
result:

  CVE-2020-12965 “Transient Execution of Non-Canonical Accesses“

Now, the kernel surrounds the access with a STAC/CLAC pair, and those
instructions end up serializing execution on older Zen architectures,
which closes the speculation window.

But that was true only up until Zen 5, which renames the AC bit [1].
That improves performance of STAC/CLAC a lot, but also means that the
speculation window is now open.

Note that this affects not just the new address masking, but also the
regular valid_user_address() check used by access_ok(), and the asm
version of the sign bit check in the get_user() helpers.

It does not affect put_user() or clear_user() variants, since there's no
speculative result to be used in a gadget for those operations.

Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Link: https://lore.kernel.org/all/80d94591-1297-4afb-b510-c665efd37f10@citrix.com/
Link: https://lore.kernel.org/all/20241023094448.GAZxjFkEOOF_DM83TQ@fat_crate.local/ [1]
Link: https://www.amd.com/en/resources/product-security/bulletin/amd-sb-1010.html
Link: https://arxiv.org/pdf/2108.10771
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Tested-by: Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com> # LAM case
Fixes: 2865baf540 ("x86: support user address masking instead of non-speculative conditional")
Fixes: 6014bc2756 ("x86-64: make access_ok() independent of LAM")
Fixes: b19b74bc99 ("x86/mm: Rework address range check in get_user() and put_user()")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-10-25 09:53:03 -07:00
Rafael J. Wysocki
1646a3f2b1 Merge branch 'pm-powercap'
Merge a dtpm_devfreq power capping driver fix for 6.12-rc5:

 - Fix a dev_pm_qos_add_request() return value check in
   __dtpm_devfreq_setup() to prevent it from failing if
   a positive number is returned (Yuan Can).

* pm-powercap:
  powercap: dtpm_devfreq: Fix error check against dev_pm_qos_add_request()
2024-10-25 17:27:19 +02:00
Rafael J. Wysocki
54774abb55 Merge branches 'acpi-resource' and 'acpi-button'
Merge new DMI quirks for 6.12-rc5:

 - Add an ACPI IRQ override quirk for LG 16T90SP (Christian Heusel).

 - Add a lid switch detection quirk for Samsung Galaxy Book2 (Shubham
   Panwar).

* acpi-resource:
  ACPI: resource: Add LG 16T90SP to irq1_level_low_skip_override[]

* acpi-button:
  ACPI: button: Add DMI quirk for Samsung Galaxy Book2 to fix initial lid detection issue
2024-10-25 17:08:14 +02:00
Miklos Szeredi
d34a5575e6 fuse: remove stray debug line
It wasn't there when the patch was posted for review, but somehow made it
into the pull.

Link: https://lore.kernel.org/all/20240913104703.1673180-1-mszeredi@redhat.com/
Fixes: efad7153bf ("fuse: allow O_PATH fd for FUSE_DEV_IOC_BACKING_OPEN")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2024-10-25 17:05:49 +02:00
Dave Airlie
4d95a12beb Merge tag 'drm-xe-fixes-2024-10-24-1' of https://gitlab.freedesktop.org/drm/xe/kernel into drm-fixes
Driver Changes:
- Increase invalidation timeout to avoid errors in some hosts (Shuicheng)
- Flush worker on timeout (Badal)
- Better handling for force wake failure (Shuicheng)
- Improve argument check on user fence creation (Nirmoy)
- Don't restart parallel queues multiple times on GT reset (Nirmoy)

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/trlkoiewtc4x2cyhsxmj3atayyq4zwto4iryea5pvya2ymc3yp@fdx5nhwmiyem
2024-10-25 16:55:39 +10:00
Steven Rostedt
a574e7f80e fgraph: Change the name of cpuhp state to "fgraph:online"
The cpuhp state name given to cpuhp_setup_state() is "fgraph_idle_init"
which doesn't really conform to the names that are used for cpu hotplug
setups. Instead rename it to "fgraph:online" to be in line with other
states.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/20241024222944.473d88c5@rorschach.local.home
Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 2c02f7375e ("fgraph: Use CPU hotplug mechanism to initialize idle shadow stacks")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-10-24 23:41:14 -04:00
Li Huafei
bd3734db86 fgraph: Fix missing unlock in register_ftrace_graph()
Use guard(mutex)() to acquire and automatically release ftrace_lock,
fixing the issue of not unlocking when calling cpuhp_setup_state()
fails.

Fixes smatch warning:

kernel/trace/fgraph.c:1317 register_ftrace_graph() warn: inconsistent returns '&ftrace_lock'.

Link: https://lore.kernel.org/20241024155917.1019580-1-lihuafei1@huawei.com
Fixes: 2c02f7375e ("fgraph: Use CPU hotplug mechanism to initialize idle shadow stacks")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202410220121.wxg0olfd-lkp@intel.com/
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-10-24 22:26:06 -04:00
Dave Airlie
e3e1cfe33f Merge tag 'drm-misc-fixes-2024-10-24' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixes
Short summary of fixes pull:

bridge:
- aux: Fix assignment of OF node
- tc358767: Add missing of_node_put() in error path

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20241024124921.GA20475@localhost.localdomain
2024-10-25 11:11:59 +10:00
Linus Torvalds
ae90f6a617 Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Pull bpf fixes from Daniel Borkmann:

 - Fix an out-of-bounds read in bpf_link_show_fdinfo for BPF sockmap
   link file descriptors (Hou Tao)

 - Fix BPF arm64 JIT's address emission with tag-based KASAN enabled
   reserving not enough size (Peter Collingbourne)

 - Fix BPF verifier do_misc_fixups patching for inlining of the
   bpf_get_branch_snapshot BPF helper (Andrii Nakryiko)

 - Fix a BPF verifier bug and reject BPF program write attempts into
   read-only marked BPF maps (Daniel Borkmann)

 - Fix perf_event_detach_bpf_prog error handling by removing an invalid
   check which would skip BPF program release (Jiri Olsa)

 - Fix memory leak when parsing mount options for the BPF filesystem
   (Hou Tao)

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf: Check validity of link->type in bpf_link_show_fdinfo()
  bpf: Add the missing BPF_LINK_TYPE invocation for sockmap
  bpf: fix do_misc_fixups() for bpf_get_branch_snapshot()
  bpf,perf: Fix perf_event_detach_bpf_prog error handling
  selftests/bpf: Add test for passing in uninit mtu_len
  selftests/bpf: Add test for writes to .rodata
  bpf: Remove MEM_UNINIT from skb/xdp MTU helpers
  bpf: Fix overloading of MEM_UNINIT's meaning
  bpf: Add MEM_WRITE attribute
  bpf: Preserve param->string when parsing mount options
  bpf, arm64: Fix address emission with tag-based KASAN enabled
2024-10-24 16:53:20 -07:00
Linus Torvalds
d44cd82264 Merge tag 'net-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Paolo Abeni:
 "Including fixes from netfiler, xfrm and bluetooth.

  Oddly this includes a fix for a posix clock regression; in our
  previous PR we included a change there as a pre-requisite for
  networking one. That fix proved to be buggy and requires the follow-up
  included here. Thomas suggested we should send it, given we sent the
  buggy patch.

  Current release - regressions:

   - posix-clock: Fix unbalanced locking in pc_clock_settime()

   - netfilter: fix typo causing some targets not to load on IPv6

  Current release - new code bugs:

   - xfrm: policy: remove last remnants of pernet inexact list

  Previous releases - regressions:

   - core: fix races in netdev_tx_sent_queue()/dev_watchdog()

   - bluetooth: fix UAF on sco_sock_timeout

   - eth: hv_netvsc: fix VF namespace also in synthetic NIC
     NETDEV_REGISTER event

   - eth: usbnet: fix name regression

   - eth: be2net: fix potential memory leak in be_xmit()

   - eth: plip: fix transmit path breakage

  Previous releases - always broken:

   - sched: deny mismatched skip_sw/skip_hw flags for actions created by
     classifiers

   - netfilter: bpf: must hold reference on net namespace

   - eth: virtio_net: fix integer overflow in stats

   - eth: bnxt_en: replace ptp_lock with irqsave variant

   - eth: octeon_ep: add SKB allocation failures handling in
     __octep_oq_process_rx()

  Misc:

   - MAINTAINERS: add Simon as an official reviewer"

* tag 'net-6.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (40 commits)
  net: dsa: mv88e6xxx: support 4000ps cycle counter period
  net: dsa: mv88e6xxx: read cycle counter period from hardware
  net: dsa: mv88e6xxx: group cycle counter coefficients
  net: usb: qmi_wwan: add Fibocom FG132 0x0112 composition
  hv_netvsc: Fix VF namespace also in synthetic NIC NETDEV_REGISTER event
  net: dsa: microchip: disable EEE for KSZ879x/KSZ877x/KSZ876x
  Bluetooth: ISO: Fix UAF on iso_sock_timeout
  Bluetooth: SCO: Fix UAF on sco_sock_timeout
  Bluetooth: hci_core: Disable works on hci_unregister_dev
  posix-clock: posix-clock: Fix unbalanced locking in pc_clock_settime()
  r8169: avoid unsolicited interrupts
  net: sched: use RCU read-side critical section in taprio_dump()
  net: sched: fix use-after-free in taprio_change()
  net/sched: act_api: deny mismatched skip_sw/skip_hw flags for actions created by classifiers
  net: usb: usbnet: fix name regression
  mlxsw: spectrum_router: fix xa_store() error checking
  virtio_net: fix integer overflow in stats
  net: fix races in netdev_tx_sent_queue()/dev_watchdog()
  net: wwan: fix global oob in wwan_rtnl_policy
  netfilter: xtables: fix typo causing some targets not to load on IPv6
  ...
2024-10-24 16:43:50 -07:00
Linus Torvalds
c9a50b9090 Merge tag 'hid-for-linus-20241024' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid
Pull HID fixes from Jiri Kosina:
 "Device-specific functionality quirks for Thinkpad X1 Gen3, Logitech
  Bolt and some Goodix touchpads (Bartłomiej Maryńczak, Hans de Goede
  and Kenneth Albanowski)"

* tag 'hid-for-linus-20241024' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid:
  HID: lenovo: Add support for Thinkpad X1 Tablet Gen 3 keyboard
  HID: multitouch: Add quirk for Logitech Bolt receiver w/ Casa touchpad
  HID: i2c-hid: Delayed i2c resume wakeup for 0x0d42 Goodix touchpad
2024-10-24 16:31:58 -07:00
Dave Airlie
2ba1f81ec7 Merge tag 'drm-intel-fixes-2024-10-24' of https://gitlab.freedesktop.org/drm/i915/kernel into drm-fixes
- Fix DRM_I915_GVT_KVMGT dependencies in Kconfig

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ZxniUlDg59RxOO-6@jlahtine-mobl.ger.corp.intel.com
2024-10-25 07:43:41 +10:00
Dominique Martinet
be2ca38253 Revert "fs/9p: simplify iget to remove unnecessary paths"
This reverts commit 724a08450f.

This code simplification introduced significant regressions on servers
that do not remap inode numbers when exporting multiple underlying
filesystems with colliding inodes, as can be illustrated with simple
tmpfs exports in qemu with remapping disabled:
```
# host side
cd /tmp/linux-test
mkdir m1 m2
mount -t tmpfs tmpfs m1
mount -t tmpfs tmpfs m2
mkdir m1/dir m2/dir
echo foo > m1/dir/foo
echo bar > m2/dir/bar

# guest side
# started with -virtfs local,path=/tmp/linux-test,mount_tag=tmp,security_model=mapped-file
mount -t 9p -o trans=virtio,debug=1 tmp /mnt/t

ls /mnt/t/m1/dir
# foo
ls /mnt/t/m2/dir
# bar (works ok if directry isn't open)

# cd to keep first dir's inode alive
cd /mnt/t/m1/dir
ls /mnt/t/m2/dir
# foo (should be bar)
```
Other examples can be crafted with regular files with fscache enabled,
in which case I/Os just happen to the wrong file leading to
corruptions, or guest failing to boot with:
  | VFS: Lookup of 'com.android.runtime' in 9p 9p would have caused loop

In theory, we'd want the servers to be smart enough and ensure they
never send us two different files with the same 'qid.path', but while
qemu has an option to remap that is recommended (and qemu prints a
warning if this case happens), there are many other servers which do
not (kvmtool, nfs-ganesha, probably diod...), we should at least ensure
we don't cause regressions on this:
- assume servers can't be trusted and operations that should get a 'new'
inode properly do so. commit d05dcfdf5e (" fs/9p: mitigate inode
collisions") attempted to do this, but v9fs_fid_iget_dotl() was not
called so some higher level of caching got in the way; this needs to be
fixed properly before we can re-apply the patches.
- if we ever want to really simplify this code, we will need to add some
negotiation with the server at mount time where the server could claim
they handle this properly, at which point we could optimize this out.
(but that might not be needed at all if we properly handle the 'new'
check?)

Fixes: 724a08450f ("fs/9p: simplify iget to remove unnecessary paths")
Reported-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/all/20240408141436.GA17022@redhat.com/
Link: https://lkml.kernel.org/r/20240923100508.GA32066@willie-the-truck
Cc: stable@vger.kernel.org # v6.9+
Message-ID: <20241024-revert_iget-v1-4-4cac63d25f72@codewreck.org>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
2024-10-25 06:26:09 +09:00