We hit softlocup with following call trace: ? asm_sysvec_apic_timer_interrupt+0x16/0x20 xa_erase+0x21/0xb0 ? sgx_free_epc_page+0x20/0x50 sgx_vepc_release+0x75/0x220 __fput+0x89/0x250 task_work_run+0x59/0x90 do_exit+0x337/0x9a0
Similar like commit 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@kernel.org Cc: Haitao Huang haitao.huang@linux.intel.com Cc: stable@vger.kernel.org Fixes: 540745ddbc70 ("x86/sgx: Introduce virtual EPC for use by KVM guests") Reported-by: Yu Zhang yu.zhang@ionos.com Tested-by: Yu Zhang yu.zhang@ionos.com Acked-by: Haitao Huang haitao.huang@linux.intel.com Reviewed-by: Jarkko Sakkinen jarkko@kernel.org Signed-off-by: Jack Wang jinpu.wang@ionos.com --- v2: * collects review and test by. * add fixes tag * trim call trace.
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(); }
/*