CVE ID:	CVE-2024-35989
Description:	In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: Fix oops during rmmod on single-CPU platforms During the removal of the idxd driver, registered offline callback is invoked as part of the clean up process. However, on systems with only one CPU online, no valid target is available to migrate the perf context, resulting in a kernel oops: BUG: unable to handle page fault for address: 000000000002a2b8 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 1470e1067 P4D 0 Oops: 0002 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 20 Comm: cpuhp/0 Not tainted 6.8.0-rc6-dsa+ #57 Hardware name: Intel Corporation AvenueCity/AvenueCity, BIOS BHSDCRB1.86B.2492.D03.2307181620 07/18/2023 RIP: 0010:mutex_lock+0x2e/0x50 ... Call Trace: __die+0x24/0x70 page_fault_oops+0x82/0x160 do_user_addr_fault+0x65/0x6b0 __pfx___rdmsr_safe_on_cpu+0x10/0x10 exc_page_fault+0x7d/0x170 asm_exc_page_fault+0x26/0x30 mutex_lock+0x2e/0x50 mutex_lock+0x1e/0x50 perf_pmu_migrate_context+0x87/0x1f0 perf_event_cpu_offline+0x76/0x90 [idxd] cpuhp_invoke_callback+0xa2/0x4f0 __pfx_perf_event_cpu_offline+0x10/0x10 [idxd] cpuhp_thread_fun+0x98/0x150 smpboot_thread_fn+0x27/0x260 smpboot_thread_fn+0x1af/0x260 __pfx_smpboot_thread_fn+0x10/0x10 kthread+0x103/0x140 __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x50 __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 Fix the issue by preventing the migration of the perf context to an invalid target.
Test IDs:	None available
Cross References:	Common Vulnerability Exposure (CVE) ID: CVE-2024-35989 https://git.kernel.org/stable/c/023b6390a15a98f9c3aa5e7da78d485d5384a08e https://git.kernel.org/stable/c/023b6390a15a98f9c3aa5e7da78d485d5384a08e https://git.kernel.org/stable/c/47533176fdcef17b114a6f688bc872901c1ec6bb https://git.kernel.org/stable/c/47533176fdcef17b114a6f688bc872901c1ec6bb https://git.kernel.org/stable/c/9edd3aa34d50f27b97be30b2ba4a6af0945ff56b https://git.kernel.org/stable/c/9edd3aa34d50f27b97be30b2ba4a6af0945ff56b https://git.kernel.org/stable/c/f221033f5c24659dc6ad7e5cf18fb1b075f4a8be https://git.kernel.org/stable/c/f221033f5c24659dc6ad7e5cf18fb1b075f4a8be https://git.kernel.org/stable/c/f976eca36cdf94e32fa4f865db0e7c427c9aa33c https://git.kernel.org/stable/c/f976eca36cdf94e32fa4f865db0e7c427c9aa33c