services: Fix pmr_el1 rewrote issue in sdei_disaptch_event()
Consider a RAS scenario:
Enter EL3 by sync exception, then call spm_mm_sp_call() enter
EL0s to handle this error, then call sdei_dispatch_event() to
inform OS. Finally, return back to OS from sync exception flow.
Similar flow is sgi_ras_intr_handler() in sgi_ras.c.
The icc_pmr_el1 register will be change in above flow:
1 cm_el1_sysregs_context_save(NON_SECURE);
-> ehf_exited_normal_world();
##icc_pmr_el1: 0xf8 => 0x80
2 spm_mm_sp_call();
3 sdei_dispatch_event();
4 ehf_activate_priority(sdei_event_priority(map));
##icc_pmr_el1: 0x80 => 0x60
5 restore_and_resume_ns_context();
-> ehf_exited_normal_world();
##return due to has_valid_pri_activations(pe_data) == 1
6 ehf_deactivate_priority(sdei_event_priority(map));
##icc_pmr_el1: 0x60 => 0x80
The icc_pmr_el1 was rewrote from 0xf8 to 0x80. This issue will
result in OS hang when eret to OS from RAS flow.
Move ehf_activate_priority(sdei_event_priority(map)) after
restore_and_resume_ns_context() can fix this issue.
Signed-off-by: Ming Huang <huangming@linux.alibaba.com>
Change-Id: If01ec55cf0aabf1594dece1ad50d3ec3406cdabc
diff --git a/services/std_svc/sdei/sdei_intr_mgmt.c b/services/std_svc/sdei/sdei_intr_mgmt.c
index f12b2ca..5d176c2 100644
--- a/services/std_svc/sdei/sdei_intr_mgmt.c
+++ b/services/std_svc/sdei/sdei_intr_mgmt.c
@@ -636,15 +636,15 @@
if (!can_sdei_state_trans(se, DO_DISPATCH))
return -1;
- /* Activate the priority corresponding to the event being dispatched */
- ehf_activate_priority(sdei_event_priority(map));
-
/*
* Prepare for NS dispatch by restoring the Non-secure context and
* marking that as active.
*/
ns_ctx = restore_and_resume_ns_context();
+ /* Activate the priority corresponding to the event being dispatched */
+ ehf_activate_priority(sdei_event_priority(map));
+
/* Dispatch event synchronously */
setup_ns_dispatch(map, se, ns_ctx, &dispatch_jmp);
begin_sdei_synchronous_dispatch(&dispatch_jmp);