On Sun, Jan 25, 2026 at 01:32:27PM +0200, Mike Rapoport wrote:
> On Thu, Jan 22, 2026 at 04:04:55AM -0800, Breno Leitao wrote:
> > Ack! I am planning something as:
> > 
> >     commit 90e098ca0d611b44594f08e50ba1cff3c932dd2b
> >     Author: Breno Leitao <[email protected]>
> >     Date:   Thu Jan 22 03:47:23 2026 -0800
> > 
> >     kho: document kexec-metadata tracking feature

...

> I'd move this section before "debugfs Interfaces", other than that LGTM.

Ack!

> > > Can't we move it into the existing if (fdt) below?
> > 
> > Unfortunately, that won't work due to a data dependency between the two
> > functions.
> > 
> > kho_process_kexec_metadata() reads from the FDT subtree and populates 
> > kho_in:
> > 
> > Basically:
> > 
> >     kho_in.kexec_count = metadata->kexec_count;
> > 
> > While kho_populate_kexec_metadata() increments metadata->kexec_count:
> > 
> >           /* kho_in.kexec_count is set to 0 on cold boot */
> >           metadata->kexec_count = kho_in.kexec_count + 1;
> > 
> > If kho_process_kexec_metadata() is moved after 
> > kho_populate_kexec_metadata(),
> > the count would always increment from 0 to 1, ignoring whatever was passed 
> > in
> > the FDT.
> > 
> > Restructuring to call kho_in_debugfs_init() earlier also doesn't work:
> > 
> > 
> >     if (fdt) {
> >             kho_in_debugfs_init(&kho_in.dbg, fdt);
> >             kho_process_kexec_metadata();
> >             return 0;
> >     }
> > 
> >     /* Populate kexec metadata for the possible next kexec */
> >     err = kho_populate_kexec_metadata();
> >     if (err)
> >                   pr_warn("failed to initialize kexec-metadata subtree: 
> > %d\n",
> >                           err);
> > 
> > This would return early without populating the kexec metadata for the next
> > kexec, breaking the chain on KHO boots.
> 
> How about we rename kho_process_kexec_metadata() to
> kho_retreive_kexec_metadata() and add kho_process_kexec_metadata() that
> will first call _retrieve and then _populate? Something like
> 
> static int __init kho_process_kexec_metadata(const void *fdt)
> {
>       int err;
> 
>       if (fdt)
>               kho_retrieve_kexec_metadata();
> 
>       /* Populate kexec metadata for the possible next kexec */
>       err = kho_populate_kexec_metadata();
>       if (err)
>               pr_warn("failed to initialize kexec-metadata subtree: %d\n",
>                       err);
> 
>       return err;
> }

That would work, I will probably rename it to kho_kexec_metadata_init()
or kho_kexec_metadata_setup() to follow the same pattern already there.

Thanks for the review, I will send an updated version soon,
--breno

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