{"cve":"CVE-2021-46970","nvd":{"published":"2024-02-27T19:04:07.303","modified":"2026-06-17T04:16:01.683","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbus: mhi: pci_generic: Remove WQ_MEM_RECLAIM flag from state workqueue\n\nA recent change created a dedicated workqueue for the state-change work\nwith WQ_HIGHPRI (no strong reason for that) and WQ_MEM_RECLAIM flags,\nbut the state-change work (mhi_pm_st_worker) does not guarantee forward\nprogress under memory pressure, and will even wait on various memory\nallocations when e.g. creating devices, loading firmware, etc... The\nwork is then not part of a memory reclaim path...\n\nMoreover, this causes a warning in check_flush_dependency() since we end\nup in code that flushes a non-reclaim workqueue:\n\n[   40.969601] workqueue: WQ_MEM_RECLAIM mhi_hiprio_wq:mhi_pm_st_worker [mhi] is flushing !WQ_MEM_RECLAIM events_highpri:flush_backlog\n[   40.969612] WARNING: CPU: 4 PID: 158 at kernel/workqueue.c:2607 check_flush_dependency+0x11c/0x140\n[   40.969733] Call Trace:\n[   40.969740]  __flush_work+0x97/0x1d0\n[   40.969745]  ? wake_up_process+0x15/0x20\n[   40.969749]  ? insert_work+0x70/0x80\n[   40.969750]  ? __queue_work+0x14a/0x3e0\n[   40.969753]  flush_work+0x10/0x20\n[   40.969756]  rollback_registered_many+0x1c9/0x510\n[   40.969759]  unregister_netdevice_queue+0x94/0x120\n[   40.969761]  unregister_netdev+0x1d/0x30\n[   40.969765]  mhi_net_remove+0x1a/0x40 [mhi_net]\n[   40.969770]  mhi_driver_remove+0x124/0x250 [mhi]\n[   40.969776]  device_release_driver_internal+0xf0/0x1d0\n[   40.969778]  device_release_driver+0x12/0x20\n[   40.969782]  bus_remove_device+0xe1/0x150\n[   40.969786]  device_del+0x17b/0x3e0\n[   40.969791]  mhi_destroy_device+0x9a/0x100 [mhi]\n[   40.969796]  ? mhi_unmap_single_use_bb+0x50/0x50 [mhi]\n[   40.969799]  device_for_each_child+0x5e/0xa0\n[   40.969804]  mhi_pm_st_worker+0x921/0xf50 [mhi]","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/0fccbf0a3b690b162f53b13ed8bc442ea33437dc","https://git.kernel.org/stable/c/abd1510c08a13c88d24b622a83c82e87ff1d3135","https://git.kernel.org/stable/c/ed541cff35cbdb695f0c98ef506dd7218883fc07","https://git.kernel.org/stable/c/0fccbf0a3b690b162f53b13ed8bc442ea33437dc","https://git.kernel.org/stable/c/abd1510c08a13c88d24b622a83c82e87ff1d3135"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:45:59.823092188+00:00"},"epss":{"cve":"CVE-2021-46970","score":0.00222,"percentile":0.12787,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}