Re: [PATCH v2 1/1] hw/arm/boot: set initrd with #[address/size]-cells type in fdt

[Schspa Shi <schspa@gmail.com>]

Peter Maydell <peter.maydell@linaro.org> writes:

> On Tue, 29 Nov 2022 at 10:48, Schspa Shi <schspa@gmail.com> wrote:
>>
>> We use 32bit value for linux,initrd-[start/end], when we have
>> loader_start > 4GB, there will be a wrong initrd_start passed
>> to the kernel, and the kernel will report the following warning.
>>
>> [    0.000000] ------------[ cut here ]------------
>> [    0.000000] initrd not fully accessible via the linear mapping -- please check your bootloader ...
>> [    0.000000] WARNING: CPU: 0 PID: 0 at arch/arm64/mm/init.c:355 arm64_memblock_init+0x158/0x244
>> [    0.000000] Modules linked in:
>> [    0.000000] CPU: 0 PID: 0 Comm: swapper Tainted: G        W          6.1.0-rc3-13250-g30a0b95b1335-dirty #28
>> [    0.000000] Hardware name: Horizon Sigi Virtual development board (DT)
>> [    0.000000] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
>> [    0.000000] pc : arm64_memblock_init+0x158/0x244
>> [    0.000000] lr : arm64_memblock_init+0x158/0x244
>> [    0.000000] sp : ffff800009273df0
>> [    0.000000] x29: ffff800009273df0 x28: 0000001000cc0010 x27: 0000800000000000
>> [    0.000000] x26: 000000000050a3e2 x25: ffff800008b46000 x24: ffff800008b46000
>> [    0.000000] x23: ffff800008a53000 x22: ffff800009420000 x21: ffff800008a53000
>> [    0.000000] x20: 0000000004000000 x19: 0000000004000000 x18: 00000000ffff1020
>> [    0.000000] x17: 6568632065736165 x16: 6c70202d2d20676e x15: 697070616d207261
>> [    0.000000] x14: 656e696c20656874 x13: 0a2e2e2e20726564 x12: 0000000000000000
>> [    0.000000] x11: 0000000000000000 x10: 00000000ffffffff x9 : 0000000000000000
>> [    0.000000] x8 : 0000000000000000 x7 : 796c6c756620746f x6 : 6e20647274696e69
>> [    0.000000] x5 : ffff8000093c7c47 x4 : ffff800008a2102f x3 : ffff800009273a88
>> [    0.000000] x2 : 80000000fffff038 x1 : 00000000000000c0 x0 : 0000000000000056
>> [    0.000000] Call trace:
>> [    0.000000]  arm64_memblock_init+0x158/0x244
>> [    0.000000]  setup_arch+0x164/0x1cc
>> [    0.000000]  start_kernel+0x94/0x4ac
>> [    0.000000]  __primary_switched+0xb4/0xbc
>> [    0.000000] ---[ end trace 0000000000000000 ]---
>> [    0.000000] Zone ranges:
>> [    0.000000]   DMA      [mem 0x0000001000000000-0x0000001007ffffff]
>>
>> To fix it, we can change it to #[address/size]-cells type.
>>
>> Signed-off-by: Schspa Shi <schspa@gmail.com>
>>
>> --
>>
>> Changelog:
>> v1 -> v2:
>>         - Use #[address/size]-cells for data type.
>> ---
>>  hw/arm/boot.c | 10 ++++++----
>>  1 file changed, 6 insertions(+), 4 deletions(-)
>>
>> diff --git a/hw/arm/boot.c b/hw/arm/boot.c
>> index 57efb61ee419..98cd1fdad2c6 100644
>> --- a/hw/arm/boot.c
>> +++ b/hw/arm/boot.c
>> @@ -638,15 +638,17 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
>>      }
>>
>>      if (binfo->initrd_size) {
>> -        rc = qemu_fdt_setprop_cell(fdt, "/chosen", "linux,initrd-start",
>> -                                   binfo->initrd_start);
>> +        rc = qemu_fdt_setprop_sized_cells(fdt, "/chosen", "linux,initrd-start",
>> +                                     acells, binfo->initrd_start);
>
> Indentation here doesn't look quite right.
>

My mistake, and fixed in the v3 patch.

>>          if (rc < 0) {
>>              fprintf(stderr, "couldn't set /chosen/linux,initrd-start\n");
>>              goto fail;
>>          }
>>
>> -        rc = qemu_fdt_setprop_cell(fdt, "/chosen", "linux,initrd-end",
>> -                                   binfo->initrd_start + binfo->initrd_size);
>> +        rc = qemu_fdt_setprop_sized_cells(fdt, "/chosen", "linux,initrd-end",
>> +                                          scells,
>> +                                          binfo->initrd_start +
>> +                                          binfo->initrd_size);
>
> This should use 'acells', not 'scells', because it's an address,
> not a size.
>

It fixed in the v3 patch too.

> thanks
> -- PMM

-- 
BRs
Schspa Shi