[PATCH v1 1/2] efi_loader: improve device path matching for partition lookup

[Balaji Selvanathan]

Hi Ilias,
Sorry for the late reply.

If the boot option generation logic skips partitions, then the boot 
option points to whole disk.

But when capsule update calls device_is_present_and_system_part() → 
efi_dp_find_obj() → find_handle(), it tries to match this boot device 
path against the ESP partition handle which has path longer than boot 
device path.

The find_handle() logic at line 142 rejects the ESP handle because:
if (len_current > len)  // ESP path is longer than boot device path
     continue;           // Skip it!

So capsule update fails to find the ESP partition.
Based on this analysis, I believe the fix I proposed would help address 
this issue, but I'd appreciate your thoughts on whether this approach 
makes sense or if there's a better way to handle it.
Thanks for your guidance!

On 8/28/2025 5:53 PM, Ilias Apalodimas wrote:
> Yes it was. In fact the original patches were adding the file instead
> of the disk [1], but we had concerns on scanning all partitions wrt to
> boot time. I don't remember if anyone tested the boot time though.