This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
The function add_mdev_supported_type() was renamed mdev_type_add() in
commit da44c340c4 ("vfio/mdev: simplify mdev_type handling").
Update the comment accordingly.
Note that just as mdev_type_release() now states that its put pairs
with the get in mdev_type_add(), mdev_type_add() already stated that
its get pairs with the put in mdev_type_release().
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20251230164113.102604-1-Julia.Lawall@inria.fr
Signed-off-by: Alex Williamson <alex@shazbot.org>
This 'struct kobj_type' is not modified. It is only used in
kobject_init_and_add() which takes a 'const struct kobj_type *ktype'
parameter.
Constifying this structure and moving it to a read-only section,
and this can increase over all security.
```
[Before]
text data bss dec hex filename
2372 600 0 2972 b9c drivers/vfio/mdev/mdev_sysfs.o
[After]
text data bss dec hex filename
2436 568 0 3004 bbc drivers/vfio/mdev/mdev_sysfs.o
```
Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20240904011837.2010444-1-lihongbo22@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *. This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.
Because the match() callback is in all busses, all busses are modified
to handle this properly. This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.
For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.
Cc: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Alex Elder <elder@kernel.org>
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The pointer to mdev_bus_compat_class is statically defined at the top
of mdev_core, and was originally (commit 7b96953bc6 ("vfio: Mediated
device Core driver") serialized by the parent_list_lock. The blamed
commit removed this mutex, leaving the pointer initialization
unserialized. As a result, the creation of multiple MDEVs in parallel
(such as during boot) can encounter errors during the creation of the
sysfs entries, such as:
[ 8.337509] sysfs: cannot create duplicate filename '/class/mdev_bus'
[ 8.337514] vfio_ccw 0.0.01d8: MDEV: Registered
[ 8.337516] CPU: 13 PID: 946 Comm: driverctl Not tainted 6.4.0-rc7 #20
[ 8.337522] Hardware name: IBM 3906 M05 780 (LPAR)
[ 8.337525] Call Trace:
[ 8.337528] [<0000000162b0145a>] dump_stack_lvl+0x62/0x80
[ 8.337540] [<00000001622aeb30>] sysfs_warn_dup+0x78/0x88
[ 8.337549] [<00000001622aeca6>] sysfs_create_dir_ns+0xe6/0xf8
[ 8.337552] [<0000000162b04504>] kobject_add_internal+0xf4/0x340
[ 8.337557] [<0000000162b04d48>] kobject_add+0x78/0xd0
[ 8.337561] [<0000000162b04e0a>] kobject_create_and_add+0x6a/0xb8
[ 8.337565] [<00000001627a110e>] class_compat_register+0x5e/0x90
[ 8.337572] [<000003ff7fd815da>] mdev_register_parent+0x102/0x130 [mdev]
[ 8.337581] [<000003ff7fdc7f2c>] vfio_ccw_sch_probe+0xe4/0x178 [vfio_ccw]
[ 8.337588] [<0000000162a7833c>] css_probe+0x44/0x80
[ 8.337599] [<000000016279f4da>] really_probe+0xd2/0x460
[ 8.337603] [<000000016279fa08>] driver_probe_device+0x40/0xf0
[ 8.337606] [<000000016279fb78>] __device_attach_driver+0xc0/0x140
[ 8.337610] [<000000016279cbe0>] bus_for_each_drv+0x90/0xd8
[ 8.337618] [<00000001627a00b0>] __device_attach+0x110/0x190
[ 8.337621] [<000000016279c7c8>] bus_rescan_devices_helper+0x60/0xb0
[ 8.337626] [<000000016279cd48>] drivers_probe_store+0x48/0x80
[ 8.337632] [<00000001622ac9b0>] kernfs_fop_write_iter+0x138/0x1f0
[ 8.337635] [<00000001621e5e14>] vfs_write+0x1ac/0x2f8
[ 8.337645] [<00000001621e61d8>] ksys_write+0x70/0x100
[ 8.337650] [<0000000162b2bdc4>] __do_syscall+0x1d4/0x200
[ 8.337656] [<0000000162b3c828>] system_call+0x70/0x98
[ 8.337664] kobject: kobject_add_internal failed for mdev_bus with -EEXIST, don't try to register things with the same name in the same directory.
[ 8.337668] kobject: kobject_create_and_add: kobject_add error: -17
[ 8.337674] vfio_ccw: probe of 0.0.01d9 failed with error -12
[ 8.342941] vfio_ccw_mdev aeb9ca91-10c6-42bc-a168-320023570aea: Adding to iommu group 2
Move the initialization of the mdev_bus_compat_class pointer to the
init path, to match the cleanup in module exit. This way the code
in mdev_register_parent() can simply link the new parent to it,
rather than determining whether initialization is required first.
Fixes: 89345d5177 ("vfio/mdev: embedd struct mdev_parent in the parent data structure")
Reported-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230626133642.2939168-1-farman@linux.ibm.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Many of the mdev drivers use a simple counter for keeping track of the
available instances. Move this code to the core code and store the counter
in the mdev_parent. Implement it using correct locking, fixing mdpy.
Drivers just provide the value in the mdev_driver at registration time
and the core code takes care of maintaining it and exposing the value in
sysfs.
[hch: count instances per-parent instead of per-type, use an atomic_t
to avoid taking mdev_list_lock in the show method]
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Link: https://lore.kernel.org/r/20220923092652.100656-15-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The device creator is supposed to use the dev.groups value to add sysfs
files before device_add is called, not call sysfs_create_files() after
device_add() returns. This creates a race with uevent delivery where the
extra attribute will not be visible.
This was being done because the groups had been co-opted by the mdev
driver, now that prior patches have moved the driver's groups to the
struct device_driver the dev.group is properly free for use here.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-34-hch@lst.de
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Linus Torvalds
Kees Cook
Julia Lawall
Heiner Kallweit
Hongbo Li
Zhang Zekun
Greg Kroah-Hartman
Ricardo B. Marliere
Jinjie Ruan
Eric Farman
Bo Liu
Christoph Hellwig
Jason Gunthorpe