On Wed, 13 Mar 2024 14:40:31 -0700, Fenghua Yu wrote:
> 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:
> <TASK>
> __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
> <TASK>
>
> [...]
Applied, thanks!
[1/1] dmaengine: idxd: Fix oops during rmmod on single-CPU platforms
commit: f221033f5c24659dc6ad7e5cf18fb1b075f4a8be
Best regards,
--
~Vinod
