Preserve dcons(4) buffer passed by loader(8).

1 files changed, 16 insertions, 0 deletions

diff --git a/sys/i386/i386/machdep.c b/sys/i386/i386/machdep.c
index ae4dc22..e17dba5 100644
--- a/sys/i386/i386/machdep.c
+++ b/sys/i386/i386/machdep.c
@@ -1533,6 +1533,7 @@ getmemsize(int first)
 	pt_entry_t *pte;
 	char *cp;
 	struct bios_smap *smap;
+	quad_t dcons_addr, dcons_size;
 
 	hasbrokenint12 = 0;
 	TUNABLE_INT_FETCH("hw.hasbrokenint12", &hasbrokenint12);
@@ -1817,6 +1818,13 @@ physmap_done:
 	pte = CMAP1;
 
 	/*
+	 * Get dcons buffer address
+	 */
+	if (getenv_quad("dcons.addr", &dcons_addr) == 0 ||
+	    getenv_quad("dcons.size", &dcons_size) == 0)
+		dcons_addr = 0;
+
+	/*
 	 * physmap is in bytes, so when converting to page boundaries,
 	 * round up the start address and round down the end address.
 	 */
@@ -1835,6 +1843,14 @@ physmap_done:
 			 */
 			if (pa >= KERNLOAD && pa < first)
 				continue;
+
+			/*
+			 * block out dcons buffer
+			 */
+			if (dcons_addr > 0
+			    && pa >= trunc_page(dcons_addr)
+			    && pa < dcons_addr + dcons_size)
+				continue;
 	
 			page_bad = FALSE;