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>

1 files changed, 8 insertions, 0 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
 	}
 }