CVE-2024-26987

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

mm/memory-failure: fix deadlock when hugetlb_optimize_vmemmap is enabled

When I did hard offline test with hugetlb pages, below deadlock occurs:

======================================================

WARNING: possible circular locking dependency detected

6.8.0-11409-gf6cef5f8c37f #1 Not tainted

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bash/46904 is trying to acquire lock:

ffffffffabe68910 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_slow_dec+0x16/0x60

but task is already holding lock:

ffffffffabf92ea8 (pcp_batch_high_lock){+.+.}-{3:3}, at: zone_pcp_disable+0x16/0x40

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (pcp_batch_high_lock){+.+.}-{3:3}:

__mutex_lock+0x6c/0x770

page_alloc_cpu_online+0x3c/0x70

cpuhp_invoke_callback+0x397/0x5f0

__cpuhp_invoke_callback_range+0x71/0xe0

_cpu_up+0xeb/0x210

cpu_up+

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References