s390/protvirt: parse prot_virt option in the decompressor

To make early kernel address space layout definition possible parse
prot_virt option in the decompressor and pass it to the uncompressed
kernel. This enables kasan to take ultravisor secure storage limit into
consideration and pre-define vmalloc position correctly.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

4 files changed, 28 insertions, 26 deletions

diff --git a/arch/s390/boot/ipl_parm.c b/arch/s390/boot/ipl_parm.c
index ae230ebd6420..92ebc4a58fe2 100644
--- a/arch/s390/boot/ipl_parm.c
+++ b/arch/s390/boot/ipl_parm.c
@@ -254,6 +254,14 @@ void parse_boot_command_line(void)
 
 		if (!strcmp(param, "nokaslr"))
 			kaslr_enabled = 0;
+
+#if IS_ENABLED(CONFIG_KVM)
+		if (!strcmp(param, "prot_virt")) {
+			rc = kstrtobool(val, &enabled);
+			if (!rc && enabled)
+				prot_virt_host = 1;
+		}
+#endif
 	}
 }
 
diff --git a/arch/s390/boot/uv.c b/arch/s390/boot/uv.c
index f887a479cdc7..a15c033f53ca 100644
--- a/arch/s390/boot/uv.c
+++ b/arch/s390/boot/uv.c
@@ -7,6 +7,9 @@
 #ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
 int __bootdata_preserved(prot_virt_guest);
 #endif
+#if IS_ENABLED(CONFIG_KVM)
+int __bootdata_preserved(prot_virt_host);
+#endif
 struct uv_info __bootdata_preserved(uv_info);
 
 void uv_query_info(void)
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index d63b08bacdf9..dd3fa7039cb0 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -1137,8 +1137,7 @@ void __init setup_arch(char **cmdline_p)
 	free_mem_detect_info();
 	remove_oldmem();
 
-	if (is_prot_virt_host())
-		setup_uv();
+	setup_uv();
 	setup_memory_end();
 	setup_memory();
 	dma_contiguous_reserve(memory_end);
diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c
index d3399b8a9b23..4233245737bd 100644
--- a/arch/s390/kernel/uv.c
+++ b/arch/s390/kernel/uv.c
@@ -26,33 +26,10 @@ int __bootdata_preserved(prot_virt_guest);
 struct uv_info __bootdata_preserved(uv_info);
 
 #if IS_ENABLED(CONFIG_KVM)
-int prot_virt_host;
+int __bootdata_preserved(prot_virt_host);
 EXPORT_SYMBOL(prot_virt_host);
 EXPORT_SYMBOL(uv_info);
 
-static int __init prot_virt_setup(char *val)
-{
-	bool enabled;
-	int rc;
-
-	rc = kstrtobool(val, &enabled);
-	if (!rc && enabled)
-		prot_virt_host = 1;
-
-	if (is_prot_virt_guest() && prot_virt_host) {
-		prot_virt_host = 0;
-		pr_warn("Protected virtualization not available in protected guests.");
-	}
-
-	if (prot_virt_host && !test_facility(158)) {
-		prot_virt_host = 0;
-		pr_warn("Protected virtualization not supported by the hardware.");
-	}
-
-	return rc;
-}
-early_param("prot_virt", prot_virt_setup);
-
 static int __init uv_init(unsigned long stor_base, unsigned long stor_len)
 {
 	struct uv_cb_init uvcb = {
@@ -74,6 +51,21 @@ void __init setup_uv(void)
 {
 	unsigned long uv_stor_base;
 
+	if (!is_prot_virt_host())
+		return;
+
+	if (is_prot_virt_guest()) {
+		prot_virt_host = 0;
+		pr_warn("Protected virtualization not available in protected guests.");
+		return;
+	}
+
+	if (!test_facility(158)) {
+		prot_virt_host = 0;
+		pr_warn("Protected virtualization not supported by the hardware.");
+		return;
+	}
+
 	uv_stor_base = (unsigned long)memblock_alloc_try_nid(
 		uv_info.uv_base_stor_len, SZ_1M, SZ_2G,
 		MEMBLOCK_ALLOC_ACCESSIBLE, NUMA_NO_NODE);