On 4/12/2023 10:32 PM, Michael Kelley (LINUX) wrote:
@@ -191,6 +222,15 @@ void hv_synic_free(void) free_page((unsigned long)hv_cpu->synic_event_page); free_page((unsigned long)hv_cpu->synic_message_page); free_page((unsigned long)hv_cpu->post_msg_page); + + if (hv_isolation_type_en_snp()) { + set_memory_encrypted((unsigned long) + hv_cpu->synic_message_page, 1); + set_memory_encrypted((unsigned long) + hv_cpu->synic_event_page, 1); + set_memory_encrypted((unsigned long) + hv_cpu->post_msg_page, 1); + }The re-encryption must be done*before* pages are freed! Furthermore, if the re-encryption fails, we should not free the page as it would pollute the free memory pool. The best we can do is leak the memory. See Patch 5 in Dexuan's TDX series, which does the same thing (but still doesn't get it quite right, per my comments).
You are right. The order is wrong. we should figure out a right solution to handle such case.
