From: Tianyu Lan <tiala@xxxxxxxxxxxxx>
VMBus post msg, synic event and message pages are shared
with hypervisor and so decrypt these pages in the sev-snp guest.
Signed-off-by: Tianyu Lan <tiala@xxxxxxxxxxxxx>
---
Change since RFC V3:
* Set encrypt page back in the hv_synic_free()
Change since RFC V2:
* Fix error in the error code path and encrypt
pages correctly when decryption failure happens.
---
drivers/hv/hv.c | 42 +++++++++++++++++++++++++++++++++++++++++-
1 file changed, 41 insertions(+), 1 deletion(-)
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index 008234894d28..e09cea8f2f04 100644
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -20,6 +20,7 @@
#include <linux/interrupt.h>
#include <clocksource/hyperv_timer.h>
#include <asm/mshyperv.h>
+#include <linux/set_memory.h>
#include "hyperv_vmbus.h"
/* The one and only */
@@ -117,7 +118,7 @@ int hv_post_message(union hv_connection_id connection_id,
int hv_synic_alloc(void)
{
- int cpu;
+ int cpu, ret;
struct hv_per_cpu_context *hv_cpu;
/*
@@ -168,9 +169,39 @@ int hv_synic_alloc(void)
pr_err("Unable to allocate post msg page\n");
goto err;
}
+
+ if (hv_isolation_type_en_snp()) {
+ ret = set_memory_decrypted((unsigned long)
+ hv_cpu->synic_message_page, 1);
+ if (ret)
+ goto err;
+
+ ret = set_memory_decrypted((unsigned long)
+ hv_cpu->synic_event_page, 1);
+ if (ret)
+ goto err_decrypt_event_page;
+
+ ret = set_memory_decrypted((unsigned long)
+ hv_cpu->post_msg_page, 1);
+ if (ret)
+ goto err_decrypt_msg_page;
+
+ memset(hv_cpu->synic_message_page, 0, PAGE_SIZE);
+ memset(hv_cpu->synic_event_page, 0, PAGE_SIZE);
+ memset(hv_cpu->post_msg_page, 0, PAGE_SIZE);
+ }
}
return 0;
+
+err_decrypt_msg_page:
+ set_memory_encrypted((unsigned long)
+ hv_cpu->synic_event_page, 1);
+
+err_decrypt_event_page:
+ set_memory_encrypted((unsigned long)
+ hv_cpu->synic_message_page, 1);
+
err:
/*
* Any memory allocations that succeeded will be freed when
@@ -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);
+ }
}
kfree(hv_context.hv_numa_map);
--
2.25.1
