Recent commit 08999b2489b4 ("x86/sgx: Free backing memory
after faulting the enclave page") expanded __sgx_encl_eldu()
to clear an enclave page's PCMD (Paging Crypto MetaData)
from the PCMD page in the backing store after the enclave
page is restored to the enclave.
Since the PCMD page in the backing store is modified the page
should be marked as dirty to ensure the modified data is retained.
Fixes: 08999b2489b4 ("x86/sgx: Free backing memory after faulting the enclave page")
Signed-off-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
---
Changes since RFC v1:
- Do not set dirty bit on enclave page since it is not being
written to and always will be discarded. (Dave)
arch/x86/kernel/cpu/sgx/encl.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c
index 398695a20605..2521d64e8bcf 100644
--- a/arch/x86/kernel/cpu/sgx/encl.c
+++ b/arch/x86/kernel/cpu/sgx/encl.c
@@ -83,6 +83,7 @@ static int __sgx_encl_eldu(struct sgx_encl_page *encl_page,
ret = -EFAULT;
}
+ set_page_dirty(b.pcmd);
memset(pcmd_page + b.pcmd_offset, 0, sizeof(struct sgx_pcmd));
/*
--
2.25.1
