Re: [PATCH v3 3/7] x86/xen: drop tests for highmem in pv code

From: Boris Ostrovsky
Date: Sat Aug 08 2020 - 22:24:36 EST


On 8/7/20 4:38 AM, Juergen Gross wrote:
> With support for 32-bit pv guests gone pure pv-code no longer needs to
> test for highmem. Dropping those tests removes the need for flushing
> in some places.
>
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>


Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>


with a suggestion


> ---
> arch/x86/xen/enlighten_pv.c | 11 ++-
> arch/x86/xen/mmu_pv.c | 138 ++++++++++++++----------------------
> 2 files changed, 57 insertions(+), 92 deletions(-)
>
> diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
> index 7d90b3da8bb4..9fec952f84f3 100644
> --- a/arch/x86/xen/enlighten_pv.c
> +++ b/arch/x86/xen/enlighten_pv.c
> @@ -347,6 +347,7 @@ static void set_aliased_prot(void *v, pgprot_t prot)
> unsigned long pfn;
> struct page *page;
> unsigned char dummy;
> + void *av;


to rename this to va since you are modifying those lines anyway.


>
> ptep = lookup_address((unsigned long)v, &level);
> BUG_ON(ptep == NULL);
> @@ -383,14 +384,10 @@ static void set_aliased_prot(void *v, pgprot_t prot)
> if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0))
> BUG();
>
> - if (!PageHighMem(page)) {
> - void *av = __va(PFN_PHYS(pfn));
> + av = __va(PFN_PHYS(pfn));
>