On 12.06.2025 12:48, Roger Pau Monné wrote: > On Thu, Jun 12, 2025 at 11:11:14AM +0200, Jan Beulich wrote: >> On 11.06.2025 19:16, Roger Pau Monne wrote: >>> This is the code already present and used by x86 in setup_max_pdx(), which >>> takes into account the current PDX compression, plus the limitation of the >>> virtual memory layout to return the maximum usable PFN in the system, >>> possibly truncating the input PFN provided by the caller. >>> >>> This helper will be used by upcoming PDX related changes that introduce a >>> new compression algorithm. >>> >>> Signed-off-by: Roger Pau Monné <roger....@citrix.com> >>> --- >>> xen/arch/x86/setup.c | 19 ++----------------- >>> xen/common/pdx.c | 25 +++++++++++++++++++++++++ >>> xen/include/xen/pdx.h | 8 ++++++++ >>> 3 files changed, 35 insertions(+), 17 deletions(-) >> >> This is all fine for x86, but on Arm you introduce unreachable code, which >> Misra dislikes. Yet then it feels like it's wrong anyway that the function >> isn't used there. > > I was also concerned regarding why ARM doesn't have an equivalent > function. Is the frametable there supposed to cover up to the maximum > physical address? In which case there's likely no need for any PDX > compression in the first place?
Question goes to Arm folks. Jan
