Re: [PATCH v3 02/14] x86/boot: Add missing handling of setup_indirect structures

[Ross Philipson]

On 8/10/21 12:19 PM, Jarkko Sakkinen wrote:
> On Mon, Aug 09, 2021 at 12:38:44PM -0400, Ross Philipson wrote:
> > One of the two functions in ioremap.c that handles setup_data was
> > missing the correct handling of setup_indirect structures.
>
> What is "correct handling", and how was it broken?
>
> What is 'setup_indirect'?
>
> > Functionality missing from original commit:
>
> Remove this sentence.
>
> > commit b3c72fc9a78e (x86/boot: Introduce setup_indirect)
>
> Should be.
>
> Fixes: b3c72fc9a78e ("x86/boot: Introduce setup_indirect")

I will fix these things and make the commit message clearer.

Thanks,
Ross

>   
> > Signed-off-by: Ross Philipson <ross.philipson@xxxxxxxxxx>
> > ---
> >   arch/x86/mm/ioremap.c | 21 +++++++++++++++++++--
> >   1 file changed, 19 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
> > index ab74e4f..f2b34c5 100644
> > --- a/arch/x86/mm/ioremap.c
> > +++ b/arch/x86/mm/ioremap.c
> > @@ -669,17 +669,34 @@ static bool __init early_memremap_is_setup_data(resource_size_t phys_addr,
> >   
> >   	paddr = boot_params.hdr.setup_data;
> >   	while (paddr) {
> > -		unsigned int len;
> > +		unsigned int len, size;
> >   
> >   		if (phys_addr == paddr)
> >   			return true;
> >   
> >   		data = early_memremap_decrypted(paddr, sizeof(*data));
> > +		size = sizeof(*data);
> >   
> >   		paddr_next = data->next;
> >   		len = data->len;
> >   
> > -		early_memunmap(data, sizeof(*data));
> > +		if ((phys_addr > paddr) && (phys_addr < (paddr + len))) {
> > +			early_memunmap(data, sizeof(*data));
> > +			return true;
> > +		}
> > +
> > +		if (data->type == SETUP_INDIRECT) {
> > +			size += len;
> > +			early_memunmap(data, sizeof(*data));
> > +			data = early_memremap_decrypted(paddr, size);
> > +
> > +			if (((struct setup_indirect *)data->data)->type != SETUP_INDIRECT) {
> > +				paddr = ((struct setup_indirect *)data->data)->addr;
> > +				len = ((struct setup_indirect *)data->data)->len;
> > +			}
> > +		}
> > +
> > +		early_memunmap(data, size);
> >   
> >   		if ((phys_addr > paddr) && (phys_addr < (paddr + len)))
> >   			return true;
> > --
> > 1.8.3.1
>
> /Jarkko