Hello Joerg Roedel,
The patch be1a5408868a: "x86/sev: Split up runtime #VC handler for
correct state tracking" from Jun 18, 2021, leads to the following
static checker warning:
arch/x86/kernel/kvm.c:153 kvm_async_pf_task_wait_schedule()
warn: sleeping in atomic context
arch/x86/kernel/sev.c
1416 * Handle #DB before calling into !noinstr code to avoid recursive #DB.
1417 */
1418 if (vc_is_db(error_code)) {
1419 exc_debug(regs);
1420 return;
1421 }
1422
1423 irq_state = irqentry_nmi_enter(regs);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
preempt disabled inside irqentry_nmi_enter().
1424
1425 instrumentation_begin();
1426
1427 if (!vc_raw_handle_exception(regs, error_code)) {
^^^^^^^^^^^^^^^^^^^^^^^^
These sleeping in atomic static checker warnings come with a lot of
caveats because the call tree is very long and it's easy to have false
positives.
--> vc_raw_handle_exception()
--> vc_forward_exception()
--> exc_page_fault()
Page faults always sleep right?
1428 /* Show some debug info */
1429 show_regs(regs);
1430
1431 /* Ask hypervisor to sev_es_terminate */
1432 sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST);
1433
1434 /* If that fails and we get here - just panic */
1435 panic("Returned from Terminate-Request to Hypervisor\n");
1436 }
1437
1438 instrumentation_end();
1439 irqentry_nmi_exit(regs, irq_state);
1440 }
regards,
dan carpenter
