On 10/31/18 12:03 AM, Mike Rapoport wrote:

On Tue, Oct 30, 2018 at 04:07:19PM -0700, Florian Fainelli wrote:

quoted

ARM64 is the only architecture that re-defines
__early_init_dt_declare_initrd() in order for that function to populate
initrd_start/initrd_end with physical addresses instead of virtual
addresses. Instead of having an override we can leverage
drivers/of/fdt.c populating phys_initrd_start/phys_initrd_size to
populate those variables for us.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 arch/arm64/mm/init.c | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 3cf87341859f..e95cee656a55 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c

@@ -72,8 +72,8 @@ static int __init early_initrd(char *p)
 	if (*endp == ',') {
 		size = memparse(endp + 1, NULL);
 
-		initrd_start = start;
-		initrd_end = start + size;
+		phys_initrd_start = start;
+		phys_initrd_size = size;
 	}
 	return 0;
 }

@@ -408,14 +408,14 @@ void __init arm64_memblock_init(void)
 		memblock_add(__pa_symbol(_text), (u64)(_end - _text));
 	}
 
-	if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && initrd_start) {
+	if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && phys_initrd_size) {
 		/*
 		 * Add back the memory we just removed if it results in the
 		 * initrd to become inaccessible via the linear mapping.
 		 * Otherwise, this is a no-op
 		 */
-		u64 base = initrd_start & PAGE_MASK;
-		u64 size = PAGE_ALIGN(initrd_end) - base;
+		u64 base = phys_initrd_start & PAGE_MASK;
+		u64 size = PAGE_ALIGN(phys_initrd_size);
 
 		/*
 		 * We can only add back the initrd memory if we don't end up

@@ -460,13 +460,10 @@ void __init arm64_memblock_init(void)
 	 */
 	memblock_reserve(__pa_symbol(_text), _end - _text);
 #ifdef CONFIG_BLK_DEV_INITRD
-	if (initrd_start) {

There may be no initrd at all, so the condition here would rather become

	if (phys_initrd_start)

Or use phys_initrd_size, which would be consistent with how other
architectures typically test for this.

quoted

-		memblock_reserve(initrd_start, initrd_end - initrd_start);
-
-		/* the generic initrd code expects virtual addresses */
-		initrd_start = __phys_to_virt(initrd_start);
-		initrd_end = __phys_to_virt(initrd_end);
-	}
+	/* the generic initrd code expects virtual addresses */
+	initrd_start = __phys_to_virt(phys_initrd_start);
+	initrd_end = initrd_start + phys_initrd_size;
+	initrd_below_start_ok = 0;
 #endif

I also wonder what is the reason to keep memstart_addr randomization and
initrd setup interleaved?

What we have now is roughly:

1) set memstart_addr
2) enforce memory_limit
3) reserve initrd
4) randomize memstart_addr
5) reserve text + data
6) reserve initrd again and set virtual addresses of initrd_{start,end}

Maybe it's possible to merge (3) into (6) ?

That's kind of orthogonal to this patch series, but it's a valid
question, not sure I would want to tackle that just now though :)
-- 
Florian