Re: [PATCH v3 02/14] xen/riscv: introduce support of Svpbmt extension and make it mandatory

[Jan Beulich <jbeulich@xxxxxxxx>]

On 21.05.2025 18:03, Oleksii Kurochko wrote:
> Svpbmt extension is necessary for chaning the memory type for a page contains
> a combination of attributes that indicate the cacheability, idempotency,
> and ordering properties for access to that page.
> 
> As a part of the patch the following is introduced:
> - Svpbmt memory type defintions: PTE_PBMT_{NOCACHE,IO}.
> - PAGE_HYPERVISOR_{NOCACHE,WC}.
> - RISCV_ISA_EXT_svpbmt and add a check in runtime that Svpbmt is
>   supported by platform.
> - Update riscv/booting.txt with information about Svpbmt.
> - Update logic of pt_update_entry() to take into account PBMT bits.
> 
> Use 'unsigned long' for pte_attr_t as PMBT bits are 61 and 62 and it doesn't
> fit into 'unsigned int'. Also, update function prototypes which uses
> 'unsigned int' for flags/attibutes.
> 
> Enable Svpbmt for testing in QEMU as Svpmbt is now mandatory for
> Xen work.
> 
> Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>

Acked-by: Jan Beulich <jbeulich@xxxxxxxx>