From: Xiaofei Tan
Sent: 27 March 2021 07:46
Replace __attribute__((packed)) by __packed following the advice of checkpatch.pl.
Signed-off-by: Xiaofei Tan tanxiaofei@huawei.com
drivers/acpi/acpi_fpdt.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/acpi/acpi_fpdt.c b/drivers/acpi/acpi_fpdt.c index a89a806..690a88a 100644 --- a/drivers/acpi/acpi_fpdt.c +++ b/drivers/acpi/acpi_fpdt.c @@ -53,7 +53,7 @@ struct resume_performance_record { u32 resume_count; u64 resume_prev; u64 resume_avg; -} __attribute__((packed)); +} __packed;
struct boot_performance_record { struct fpdt_record_header header; @@ -63,13 +63,13 @@ struct boot_performance_record { u64 bootloader_launch; u64 exitbootservice_start; u64 exitbootservice_end; -} __attribute__((packed)); +} __packed;
struct suspend_performance_record { struct fpdt_record_header header; u64 suspend_start; u64 suspend_end; -} __attribute__((packed)); +} __packed;
My standard question about 'packed' is whether it is actually needed. It should only be used if the structures might be misaligned in memory. If the only problem is that a 64bit item needs to be 32bit aligned then a suitable type should be used for those specific fields.
Those all look very dubious - the standard header isn't packed so everything must eb assumed to be at least 32bit aligned.
There are also other sub-structures that contain 64bit values. These don't contain padding - but that requires 64bit alignement.
The only problematic structure is the last one - which would have a 32bit pad after the header. Is this even right given than there are explicit alignment pads in some of the other structures.
If 64bit alignment isn't guaranteed then a '64bit aligned to 32bit' type should be used for the u64 fields.
David
- Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)