On Thu, Apr 25, 2024 at 09:26:59AM +0200, Jan Beulich wrote: > On 25.04.2024 09:10, Roger Pau Monné wrote: > > On Thu, Apr 25, 2024 at 08:12:09AM +0200, Jan Beulich wrote: > >> On 24.04.2024 21:18, Daniel P. Smith wrote: > >>> @@ -1089,6 +1098,9 @@ static int __init pvh_setup_acpi_xsdt(struct domain > >>> *d, paddr_t madt_addr, > >>> xsdt->header = *table; > >>> acpi_os_unmap_memory(table, sizeof(*table)); > >>> > >>> + /* In case the header is an RSDT copy, blindly ensure it has an XSDT > >>> sig */ > >>> + xsdt->header.signature[0] = 'X'; > >> > >> This is in no way "blindly". The size of the table elements being different > >> between RSDT and XSDT makes it mandatory to have the correct signature. > >> Else > >> the consumer of the struct is going to be misled. > > > > The "blindly" IMO refers to the fact that the table might already have > > the right signature, but this is not checked, IOW we could do: > > > > if ( xsdt->header.signature[0] == 'R' ) > > xsdt->header.signature[0] = 'X'; > > Right, and indeed I was seeing this as a possible further interpretation. > Yet given multiple ways of reading this, I'm of the opinion that it wants > adjusting. ", ... unconditionally ensure it has ... " may already do. > Simply dropping "blindly" would too be okay with me.
FWIW, I'm fine with any of the proposed adjustments. Thanks, Roger.
