KVM: SEV: shorten comments around sev_clflush_pages (14e3dd8d) · Commits · 戴 / test

arch/x86/kvm/svm/sev.c

+7 −12

Original line number	Diff line number	Diff line
		@@ -446,10 +446,8 @@ static int sev_launch_update_data(struct kvm kvm, struct kvm_sev_cmd argp)
		}

		/*
		* The LAUNCH_UPDATE command will perform in-place encryption of the
		* memory content (i.e it will write the same memory region with C=1).
		* It's possible that the cache may contain the data with C=0, i.e.,
		* unencrypted so invalidate it first.
		* Flush (on non-coherent CPUs) before LAUNCH_UPDATE encrypts pages in
		* place; the cache may contain the data that was written unencrypted.
		*/
		sev_clflush_pages(inpages, npages);

		@@ -805,10 +803,9 @@ static int sev_dbg_crypt(struct kvm kvm, struct kvm_sev_cmd argp, bool dec)
		}

		/*
		* The DBG_{DE,EN}CRYPT commands will perform {dec,en}cryption of the
		* memory content (i.e it will write the same memory region with C=1).
		* It's possible that the cache may contain the data with C=0, i.e.,
		* unencrypted so invalidate it first.
		* Flush (on non-coherent CPUs) before DBG_{DE,EN}CRYPT read or modify
		* the pages; flush the destination too so that future accesses do not
		* see stale data.
		*/
		sev_clflush_pages(src_p, 1);
		sev_clflush_pages(dst_p, 1);
		@@ -870,10 +867,8 @@ static int sev_launch_secret(struct kvm kvm, struct kvm_sev_cmd argp)
		return PTR_ERR(pages);

		/*
		* The LAUNCH_SECRET command will perform in-place encryption of the
		* memory content (i.e it will write the same memory region with C=1).
		* It's possible that the cache may contain the data with C=0, i.e.,
		* unencrypted so invalidate it first.
		* Flush (on non-coherent CPUs) before LAUNCH_SECRET encrypts pages in
		* place; the cache may contain the data that was written unencrypted.
		*/
		sev_clflush_pages(pages, n);

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