On Mon Aug 14, 2023 at 7:37 AM EEST, Jack Wang wrote:
> We hit softlocup with following call trace:
> kernel: [ 2041.288210] Call Trace:
> kernel: [ 2041.288213] <IRQ>
> kernel: [ 2041.288216] ? watchdog_timer_fn+0x1b4/0x210
> kernel: [ 2041.288222] ? lockup_detector_update_enable+0x50/0x50
> kernel: [ 2041.288225] ? __hrtimer_run_queues+0x127/0x280
> kernel: [ 2041.288230] ? hrtimer_interrupt+0xfc/0x210
> kernel: [ 2041.288233] ? __sysvec_apic_timer_interrupt+0x59/0xd0
> kernel: [ 2041.288237] ? sysvec_apic_timer_interrupt+0x6d/0x90
> kernel: [ 2041.288242] </IRQ>
> kernel: [ 2041.288242] <TASK>
> kernel: [ 2041.288244] ? asm_sysvec_apic_timer_interrupt+0x16/0x20
> kernel: [ 2041.288250] xa_erase+0x21/0xb0
> kernel: [ 2041.288256] ? sgx_free_epc_page+0x20/0x50
> kernel: [ 2041.288260] sgx_vepc_release+0x75/0x220
> kernel: [ 2041.288263] __fput+0x89/0x250
> kernel: [ 2041.288269] task_work_run+0x59/0x90
> kernel: [ 2041.288275] do_exit+0x337/0x9a0
>
> Similar like 8795359e35bc ("x86/sgx: Silence softlockup detection when releasing large enclaves")
> The test system has 64GB of enclave memory, and all assigned to a single
> VM. Release vepc take longer time and triggers the softlockup warning.
>
> Add a cond_resched() to give other tasks a chance to run and placate
> the softlockup detector.
>
> Cc: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
> Cc: Haitao Huang <haitao.huang@xxxxxxxxxxxxxxx>
> Reported-by: Yu Zhang <yu.zhang@xxxxxxxxx>
>
> Signed-off-by: Jack Wang <jinpu.wang@xxxxxxxxx>
> ---
> arch/x86/kernel/cpu/sgx/virt.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/x86/kernel/cpu/sgx/virt.c b/arch/x86/kernel/cpu/sgx/virt.c
> index c3e37eaec8ec..01d2795792cc 100644
> --- a/arch/x86/kernel/cpu/sgx/virt.c
> +++ b/arch/x86/kernel/cpu/sgx/virt.c
> @@ -204,6 +204,7 @@ static int sgx_vepc_release(struct inode *inode, struct file *file)
> continue;
>
> xa_erase(&vepc->page_array, index);
> + cond_resched();
> }
>
> /*
> @@ -222,6 +223,7 @@ static int sgx_vepc_release(struct inode *inode, struct file *file)
> list_add_tail(&epc_page->list, &secs_pages);
>
> xa_erase(&vepc->page_array, index);
> + cond_resched();
> }
>
> /*
> --
> 2.34.1
Thank you for looking into this.
Reviewed-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
BR, Jarkko
