kernel/git/next/linux-next.git/drivers/virt/acrn/irqfd.c, branch master

Merge tag 'char-misc-7.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2026-06-22T19:20:21+00:00

Pull misc driver updates from Greg KH: "Here is the big set of char, misc, iio, fpga, and other small driver subsystems changes for 7.2-rc1. Lots of little stuff in here, the majority being of course the IIO driver updates, as a list they are: - IIO driver updates and additions - GPIB driver bugfixes and cleanups - Android binder driver updates (rust and C version) - counter driver updates - MHI driver updates - mei driver updates - w1 driver updates - interconnect driver updates - Comedi driver fixes and updates - some obsolete char drivers removed (applicom and dtlk) - hwtracing driver updates - other tiny driver updates All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-7.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (406 commits) w1: ds2482: Use named initializers for arrays of i2c_device_data firmware: stratix10-svc: Add support to query Arm Trusted Firmware (ATF) version firmware: stratix10-rsu: avoid blocking reboot_image sysfs when busy coresight: ultrasoc-smb: Fix OOB write in smb_sync_perf_buffer() iio: adc: nxp-sar-adc: harden buffer ISR against per-channel read failure iio: chemical: scd30: Replace manual locking with RAII locking iio: light: tsl2591: remove unneeded tsl2591_compatible_als_persist_cycle() iio: dac: ad5686: create bus ops struct iio: dac: ad5686: cleanup doc header of local structs iio: dac: ad5686: add control_sync() for single-channel devices iio: dac: ad5686: add helpers to handle powerdown masks iio: dac: ad5686: add of_match table to the spi driver iio: dac: ad5686: drop enum id iio: dac: ad5686: remove redundant register definition iio: dac: ad5686: refactor include headers iio: adc: ad4080: fix AD4880 chip ID iio: light: veml3328: add support for new device dt-bindings: iio: light: veml6030: add veml3328 fpga: microchip-spi: fix zero header_size OOB read in mpf_ops_parse_header() fpga: dfl-afu: validate DMA mapping length in afu_dma_map_region() ...

virt: acrn: Fix irqfd use-after-free during eventfd shutdown

2026-05-23T11:47:34+00:00

acrn_irqfd_deassign() and the eventfd EPOLLHUP wakeup can race and free the same struct hsm_irqfd: CPU0 CPU1 ---- ---- eventfd_release() wake_up_poll(EPOLLHUP) hsm_irqfd_wakeup() queue_work(&irqfd->shutdown) acrn_irqfd_deassign() hsm_irqfd_shutdown() list_del_init() eventfd_ctx_remove_wait_queue() eventfd_ctx_put() kfree(irqfd) hsm_irqfd_shutdown_work() container_of(work, ..., shutdown) irqfd->vm <-- use-after-free The deassign path freed the irqfd while a shutdown work item was already queued by EPOLLHUP (or vice versa), so the work item could resurrect a dangling pointer through container_of(). Switch to the lifetime model used by KVM irqfds: - Deassign/deinit only deactivate the irqfd: remove it from vm->irqfds under irqfds_lock and queue the cleanup work. - hsm_irqfd_shutdown_work() becomes the sole owner that unhooks the eventfd waitqueue entry, drops the eventfd reference and frees the irqfd. - A new HSM_IRQFD_FLAG_SHUTDOWN bit guarded by test_and_set_bit() ensures the cleanup work is queued at most once, no matter how many of {EPOLLHUP, deassign, deinit} fire concurrently. This is safe to call from the waitqueue callback, which runs with wqh->lock held and IRQs disabled and therefore cannot take irqfds_lock. - acrn_irqfd_deassign() flushes vm->irqfd_wq before returning so the eventfd is fully detached on return. acrn_irqfd_deinit() deactivates every irqfd, flushes the workqueue and only then destroys it, so no path can queue_work() onto a torn-down workqueue. - acrn_irqfd_assign() now installs the eventfd waitqueue entry and publishes the irqfd to vm->irqfds under irqfds_lock, so the irqfd is never visible to deassign/deinit before its waitqueue entry is in place, and any EPOLLHUP that fires in the assign window queues cleanup work that blocks on irqfds_lock until publication is done. Signed-off-by: Sicong Huang Reviewed-by: Fei Li Link: https://patch.msgid.link/20260519112018.2135000-2-congei42@163.com Signed-off-by: Greg Kroah-Hartman

virt: acrn: Add WQ_PERCPU to alloc_workqueue users

2026-05-07T21:29:38+00:00

This continues the effort to refactor workqueue APIs, which began with the introduction of new workqueues and a new alloc_workqueue flag in: commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq") commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag") The refactoring is going to alter the default behavior of alloc_workqueue() to be unbound by default. With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND), any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND must now use WQ_PERCPU. For more details see the Link tag below. In order to keep alloc_workqueue() behavior identical, explicitly request WQ_PERCPU. Cc: Fei Li Link: https://lore.kernel.org/all/20250221112003.1dSuoGyc@linutronix.de/ Suggested-by: Tejun Heo Signed-off-by: Marco Crivellari Signed-off-by: Tejun Heo

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

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

virt: acrn: Remove unused list 'acrn_irqfd_clients'

2025-05-01T15:57:24+00:00

It doesn't look like this was ever used. Build tested only. Signed-off-by: "Dr. David Alan Gilbert" Acked-by: Fei Li Link: https://lore.kernel.org/r/20250430003623.313541-1-linux@treblig.org Signed-off-by: Greg Kroah-Hartman

assorted variants of irqfd setup: convert to CLASS(fd)

2024-11-03T06:28:07+00:00

in all of those failure exits prior to fdget() are plain returns and the only thing done after fdput() is (on failure exits) a kfree(), which can be done before fdput() just fine. NOTE: in acrn_irqfd_assign() 'fail:' failure exit is wrong for eventfd_ctx_fileget() failure (we only want fdput() there) and once we stop doing that, it doesn't need to check if eventfd is NULL or ERR_PTR(...) there. NOTE: in privcmd we move fdget() up before the allocation - more to the point, before the copy_from_user() attempt. Signed-off-by: Al Viro

introduce fd_file(), convert all accessors to it.

2024-08-13T02:00:43+00:00

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

virt: acrn: Remove unsued acrn_irqfds_mutex.

2022-03-18T12:49:49+00:00

acrn_irqfds_mutex is not used, never was. Remove acrn_irqfds_mutex. Fixes: aa3b483ff1d71 ("virt: acrn: Introduce irqfd") Cc: Fei Li Signed-off-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/YidLo57Kw/u/cpA5@linutronix.de Signed-off-by: Greg Kroah-Hartman

virt: acrn: Use EPOLLIN instead of POLLIN

2021-03-10T08:50:23+00:00

This fixes the following sparse warning: "sparse warnings: (new ones prefixed by >>)" >> drivers/virt/acrn/irqfd.c:163:13: sparse: sparse: restricted __poll_t degrades to integer Fixes: dcf9625f2adf ("virt: acrn: Use vfs_poll() instead of f_op->poll()") Reported-by: kernel test robot Acked-by: Shuo Liu Signed-off-by: Yejune Deng Link: https://lore.kernel.org/r/20210310074901.7486-1-yejune.deng@gmail.com Signed-off-by: Greg Kroah-Hartman