On 5 November 2018 at 21:41, Florian Fainelli [off-list ref] wrote:

On 11/5/18 12:39 PM, Ard Biesheuvel wrote:

quoted

Hi Florian,

On 31 October 2018 at 20:28, Florian Fainelli [off-list ref] 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 | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 3cf87341859f..00ef2166bb73 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

@@ -460,12 +460,11 @@ void __init arm64_memblock_init(void)
         */
        memblock_reserve(__pa_symbol(_text), _end - _text);
 #ifdef CONFIG_BLK_DEV_INITRD
-       if (initrd_start) {
-               memblock_reserve(initrd_start, initrd_end - initrd_start);
-
+       if (phys_initrd_size) {
                /* the generic initrd code expects virtual addresses */
-               initrd_start = __phys_to_virt(initrd_start);
-               initrd_end = __phys_to_virt(initrd_end);
+               initrd_start = __phys_to_virt(phys_initrd_start);
+               initrd_end = initrd_start + phys_initrd_size;
+               initrd_below_start_ok = 0;

Where is this assignment coming from?

__early_init_dt_declare_initrd() sets initrd_below_start_ok to 1 though
after patch #5 this is not necessary any more.

Yes, but why? The original arm64 version of
__early_init_dt_declare_initrd() does not set it but now you set to 1
in the IS_ENABLED(CONFIG_ARM64) section in the generic code and set it
back to 0 here.

Or am I missing something?