[PATCH RESEND] block: store GPT attributes as a raw value

[PATCH RESEND] block: store GPT attributes as a raw value

[Vincent Mailhol]

struct _gpt_entry_attributes currently models the GPT partition entry
attributes field with bitfields. This is broken on machines using the
__BIG_ENDIAN_BITFIELD ABI because GPT always stores the attributes on
disk as a 64-bit little-endian.

No current code consumes individual fields from that structure. So just
remove struct _gpt_entry_attributes entirely and replace it by an __le64
value in struct _gpt_entry instead. This lets users apply endian-aware
masks explicitly when inspecting attribute bits.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
---
 block/partitions/efi.h | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/block/partitions/efi.h b/block/partitions/efi.h
index 84b9f36b9e47..1f56f93b2804 100644
--- a/block/partitions/efi.h
+++ b/block/partitions/efi.h
@@ -75,18 +75,12 @@ typedef struct _gpt_header {
 	 */
 } __packed gpt_header;
 
-typedef struct _gpt_entry_attributes {
-	u64 required_to_function:1;
-	u64 reserved:47;
-        u64 type_guid_specific:16;
-} __packed gpt_entry_attributes;
-
 typedef struct _gpt_entry {
 	efi_guid_t partition_type_guid;
 	efi_guid_t unique_partition_guid;
 	__le64 starting_lba;
 	__le64 ending_lba;
-	gpt_entry_attributes attributes;
+	__le64 attributes;
 	__le16 partition_name[72/sizeof(__le16)];
 } __packed gpt_entry;
 

---
base-commit: 1590cf0329716306e948a8fc29f1d3ee87d3989f
change-id: 20260724-fix_gpt_entry_attributes-e5af9e080ce1

Best regards,
-- 
Vincent Mailhol <mailhol@kernel.org>

Re: [PATCH RESEND] block: store GPT attributes as a raw value

[Christoph Hellwig]

On Tue, Sep 08, 2026 at 08:58:26PM +0200, Vincent Mailhol wrote:
> struct _gpt_entry_attributes currently models the GPT partition entry
> attributes field with bitfields. This is broken on machines using the
> __BIG_ENDIAN_BITFIELD ABI because GPT always stores the attributes on
> disk as a 64-bit little-endian.
> 
> No current code consumes individual fields from that structure. So just
> remove struct _gpt_entry_attributes entirely and replace it by an __le64
> value in struct _gpt_entry instead. This lets users apply endian-aware
> masks explicitly when inspecting attribute bits.

This is much better.  If we ever need to interpret it swe should use
le64_to_cpu and masking/shifting anyway.

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [PATCH RESEND] block: store GPT attributes as a raw value

[Davidlohr Bueso]

On 2026-09-08 11:58, Vincent Mailhol wrote:
> struct _gpt_entry_attributes currently models the GPT partition entry
> attributes field with bitfields. This is broken on machines using the
> __BIG_ENDIAN_BITFIELD ABI because GPT always stores the attributes on
> disk as a 64-bit little-endian.
> 
> No current code consumes individual fields from that structure. So just
> remove struct _gpt_entry_attributes entirely and replace it by an 
> __le64
> value in struct _gpt_entry instead. This lets users apply endian-aware
> masks explicitly when inspecting attribute bits.
> 
> Signed-off-by: Vincent Mailhol <mailhol@kernel.org>

Acked-by: Davidlohr Bueso <dave@stgolabs.net>

Re: [PATCH RESEND] block: store GPT attributes as a raw value

[Jens Axboe]

On Tue, 08 Sep 2026 20:58:26 +0200, Vincent Mailhol wrote:
> struct _gpt_entry_attributes currently models the GPT partition entry
> attributes field with bitfields. This is broken on machines using the
> __BIG_ENDIAN_BITFIELD ABI because GPT always stores the attributes on
> disk as a 64-bit little-endian.
> 
> No current code consumes individual fields from that structure. So just
> remove struct _gpt_entry_attributes entirely and replace it by an __le64
> value in struct _gpt_entry instead. This lets users apply endian-aware
> masks explicitly when inspecting attribute bits.
> 
> [...]

Applied, thanks!

[1/1] block: store GPT attributes as a raw value
      commit: 74ea55a6ecb3fd69b47b2b8a6f6979a6c79c7ce7

Best regards,
-- 
Jens Axboe