kernel.git/drivers/xen/privcmd.c, branch linux-6.12.y

xen: Remove dependency between pciback and privcmd

2024-10-18T09:59:04Z

Commit 2fae6bb7be32 ("xen/privcmd: Add new syscall to get gsi from dev") adds a weak reverse dependency to the config XEN_PRIVCMD definition, that dependency causes xen-privcmd can't be loaded on domU, because dependent xen-pciback isn't always be loaded successfully on domU. To solve above problem, remove that dependency, and do not call pcistub_get_gsi_from_sbdf() directly, instead add a hook in drivers/xen/apci.c, xen-pciback register the real call function, then in privcmd_ioctl_pcidev_get_gsi call that hook. Fixes: 2fae6bb7be32 ("xen/privcmd: Add new syscall to get gsi from dev") Reported-by: Marek Marczykowski-Górecki Signed-off-by: Jiqian Chen Reviewed-by: Juergen Gross Message-ID: <20241012084537.1543059-1-Jiqian.Chen@amd.com> Signed-off-by: Juergen Gross

Merge tag 'for-linus-6.12-rc1a-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2024-09-27T16:55:30Z

Pull more xen updates from Juergen Gross: "A second round of Xen related changes and features: - a small fix of the xen-pciback driver for a warning issued by sparse - support PCI passthrough when using a PVH dom0 - enable loading the kernel in PVH mode at arbitrary addresses, avoiding conflicts with the memory map when running as a Xen dom0 using the host memory layout" * tag 'for-linus-6.12-rc1a-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/pvh: Add 64bit relocation page tables x86/kernel: Move page table macros to header x86/pvh: Set phys_base when calling xen_prepare_pvh() x86/pvh: Make PVH entrypoint PIC for x86-64 xen: sync elfnote.h from xen tree xen/pciback: fix cast to restricted pci_ers_result_t and pci_power_t xen/privcmd: Add new syscall to get gsi from dev xen/pvh: Setup gsi for passthrough device xen/pci: Add a function to reset device for xen

xen/privcmd: Add new syscall to get gsi from dev

2024-09-25T07:54:55Z

On PVH dom0, when passthrough a device to domU, QEMU and xl tools want to use gsi number to do pirq mapping, see QEMU code xen_pt_realize->xc_physdev_map_pirq, and xl code pci_add_dm_done->xc_physdev_map_pirq, but in current codes, the gsi number is got from file /sys/bus/pci/devices//irq, that is wrong, because irq is not equal with gsi, they are in different spaces, so pirq mapping fails. And in current linux codes, there is no method to get gsi for userspace. For above purpose, record gsi of pcistub devices when init pcistub and add a new syscall into privcmd to let userspace can get gsi when they have a need. Signed-off-by: Jiqian Chen Signed-off-by: Huang Rui Signed-off-by: Jiqian Chen Reviewed-by: Stefano Stabellini Message-ID: <20240924061437.2636766-4-Jiqian.Chen@amd.com> Signed-off-by: Juergen Gross

introduce fd_file(), convert all accessors to it.

2024-08-13T02:00:43Z

For any changes of struct fd representation we need to turn existing accesses to fields into calls of wrappers. Accesses to struct fd::flags are very few (3 in linux/file.h, 1 in net/socket.c, 3 in fs/overlayfs/file.c and 3 more in explicit initializers). Those can be dealt with in the commit converting to new layout; accesses to struct fd::file are too many for that. This commit converts (almost) all of f.file to fd_file(f). It's not entirely mechanical ('file' is used as a member name more than just in struct fd) and it does not even attempt to distinguish the uses in pointer context from those in boolean context; the latter will be eventually turned into a separate helper (fd_empty()). NOTE: mass conversion to fd_empty(), tempting as it might be, is a bad idea; better do that piecewise in commit that convert from fdget...() to CLASS(...). [conflicts in fs/fhandle.c, kernel/bpf/syscall.c, mm/memcontrol.c caught by git; fs/stat.c one got caught by git grep] [fs/xattr.c conflict] Reviewed-by: Christian Brauner Signed-off-by: Al Viro

xen: privcmd: Fix possible access to a freed kirqfd instance

2024-07-02T10:23:42Z

Nothing prevents simultaneous ioctl calls to privcmd_irqfd_assign() and privcmd_irqfd_deassign(). If that happens, it is possible that a kirqfd created and added to the irqfds_list by privcmd_irqfd_assign() may get removed by another thread executing privcmd_irqfd_deassign(), while the former is still using it after dropping the locks. This can lead to a situation where an already freed kirqfd instance may be accessed and cause kernel oops. Use SRCU locking to prevent the same, as is done for the KVM implementation for irqfds. Reported-by: Al Viro Suggested-by: Paolo Bonzini Signed-off-by: Viresh Kumar Reviewed-by: Juergen Gross Link: https://lore.kernel.org/r/9e884af1f1f842eacbb7afc5672c8feb4dea7f3f.1718703669.git.viresh.kumar@linaro.org Signed-off-by: Juergen Gross

xen: privcmd: Switch from mutex to spinlock for irqfds

2024-07-02T10:23:39Z

irqfd_wakeup() gets EPOLLHUP, when it is called by eventfd_release() by way of wake_up_poll(&ctx->wqh, EPOLLHUP), which gets called under spin_lock_irqsave(). We can't use a mutex here as it will lead to a deadlock. Fix it by switching over to a spin lock. Reported-by: Al Viro Signed-off-by: Viresh Kumar Reviewed-by: Juergen Gross Link: https://lore.kernel.org/r/a66d7a7a9001424d432f52a9fc3931a1f345464f.1718703669.git.viresh.kumar@linaro.org Signed-off-by: Juergen Gross

xen: add missing MODULE_DESCRIPTION() macros

2024-07-02T07:41:46Z

With ARCH=x86, make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/xen/xen-pciback/xen-pciback.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/xen/xen-evtchn.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/xen/xen-privcmd.o Add the missing invocations of the MODULE_DESCRIPTION() macro. Signed-off-by: Jeff Johnson Reviewed-by: Juergen Gross Link: https://lore.kernel.org/r/20240611-md-drivers-xen-v1-1-1eb677364ca6@quicinc.com Signed-off-by: Juergen Gross

xen/privcmd: Use memdup_array_user() in alloc_ioreq()

2024-02-13T07:58:21Z

* The function “memdup_array_user” was added with the commit 313ebe47d75558511aa1237b6e35c663b5c0ec6f ("string.h: add array-wrappers for (v)memdup_user()"). Thus use it accordingly. This issue was detected by using the Coccinelle software. * Delete a label which became unnecessary with this refactoring. Signed-off-by: Markus Elfring Reviewed-by: Juergen Gross Link: https://lore.kernel.org/r/41e333f7-1f3a-41b6-a121-a3c0ae54e36f@web.de Signed-off-by: Juergen Gross

Merge tag 'vfs-6.8.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2024-01-08T18:26:08Z

Pull misc vfs updates from Christian Brauner: "This contains the usual miscellaneous features, cleanups, and fixes for vfs and individual fses. Features: - Add Jan Kara as VFS reviewer - Show correct device and inode numbers in proc//maps for vma files on stacked filesystems. This is now easily doable thanks to the backing file work from the last cycles. This comes with selftests Cleanups: - Remove a redundant might_sleep() from wait_on_inode() - Initialize pointer with NULL, not 0 - Clarify comment on access_override_creds() - Rework and simplify eventfd_signal() and eventfd_signal_mask() helpers - Process aio completions in batches to avoid needless wakeups - Completely decouple struct mnt_idmap from namespaces. We now only keep the actual idmapping around and don't stash references to namespaces - Reformat maintainer entries to indicate that a given subsystem belongs to fs/ - Simplify fput() for files that were never opened - Get rid of various pointless file helpers - Rename various file helpers - Rename struct file members after SLAB_TYPESAFE_BY_RCU switch from last cycle - Make relatime_need_update() return bool - Use GFP_KERNEL instead of GFP_USER when allocating superblocks - Replace deprecated ida_simple_*() calls with their current ida_*() counterparts Fixes: - Fix comments on user namespace id mapping helpers. They aren't kernel doc comments so they shouldn't be using /** - s/Retuns/Returns/g in various places - Add missing parameter documentation on can_move_mount_beneath() - Rename i_mapping->private_data to i_mapping->i_private_data - Fix a false-positive lockdep warning in pipe_write() for watch queues - Improve __fget_files_rcu() code generation to improve performance - Only notify writer that pipe resizing has finished after setting pipe->max_usage otherwise writers are never notified that the pipe has been resized and hang - Fix some kernel docs in hfsplus - s/passs/pass/g in various places - Fix kernel docs in ntfs - Fix kcalloc() arguments order reported by gcc 14 - Fix uninitialized value in reiserfs" * tag 'vfs-6.8.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (36 commits) reiserfs: fix uninit-value in comp_keys watch_queue: fix kcalloc() arguments order ntfs: dir.c: fix kernel-doc function parameter warnings fs: fix doc comment typo fs tree wide selftests/overlayfs: verify device and inode numbers in /proc/pid/maps fs/proc: show correct device and inode numbers in /proc/pid/maps eventfd: Remove usage of the deprecated ida_simple_xx() API fs: super: use GFP_KERNEL instead of GFP_USER for super block allocation fs/hfsplus: wrapper.c: fix kernel-doc warnings fs: add Jan Kara as reviewer fs/inode: Make relatime_need_update return bool pipe: wakeup wr_wait after setting max_usage file: remove __receive_fd() file: stop exposing receive_fd_user() fs: replace f_rcuhead with f_task_work file: remove pointless wrapper file: s/close_fd_get_file()/file_close_fd()/g Improve __fget_files_rcu() code generation (and thus __fget_light()) file: massage cleanup of files that failed to open fs/pipe: Fix lockdep false-positive in watchqueue pipe_write() ...

eventfd: simplify eventfd_signal()

2023-11-28T13:08:38Z

Ever since the eventfd type was introduced back in 2007 in commit e1ad7468c77d ("signal/timer/event: eventfd core") the eventfd_signal() function only ever passed 1 as a value for @n. There's no point in keeping that additional argument. Link: https://lore.kernel.org/r/20231122-vfs-eventfd-signal-v2-2-bd549b14ce0c@kernel.org Acked-by: Xu Yilun Acked-by: Andrew Donnellan # ocxl Acked-by: Eric Farman # s390 Reviewed-by: Jan Kara Reviewed-by: Jens Axboe Signed-off-by: Christian Brauner