RE: [PATCH v3] efi: take size of partition entry from GPT header

From: David Laight
Date: Thu Sep 13 2018 - 09:23:03 EST


From: Davidlohr Bueso
> Sent: 12 September 2018 19:55
>
> On Wed, 12 Sep 2018, Eugene Korenevsky wrote:
> > /**
> > * efi_partition(struct parsed_partitions *state)
> > * @state: disk parsed partitions
> >@@ -704,32 +710,36 @@ int efi_partition(struct parsed_partitions *state)
> >
> > pr_debug("GUID Partition Table is valid! Yea!\n");
> >
> >- for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) {
> >+ for (i = 0;
> >+ i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1;
> >+ i++) {
>
> Please rearrange this like:
>
> for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) &&
> i < state->limit-1; i++)

Better still cache le32_to_cpu(gpt->num_partition_entries) to a local
so that it only has to be calculated once (even if it gets spilled
to the stack).
It can be bounded by state->limit-1 at the same time.

David

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