Re: [PATCH v3] x86/pci-dma: add a SWIOTLB_ANY flag to lift the low mem limitation

[Borislav Petkov]

On Wed, Jun 24, 2026 at 01:22:33AM +0000, Miao, Jun wrote:
> >> diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
> >> index 6267363e0189..73b9320c4a7d 100644
> >> --- a/arch/x86/kernel/pci-dma.c
> >> +++ b/arch/x86/kernel/pci-dma.c
> >> @@ -61,7 +61,7 @@ static void __init pci_swiotlb_detect(void)
> >>  	 */
> >>  	if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) {
> >>  		x86_swiotlb_enable = true;
> >> -		x86_swiotlb_flags |= SWIOTLB_FORCE;
> >> +		x86_swiotlb_flags |= SWIOTLB_ANY | SWIOTLB_FORCE;
> >
> >This is not TDX-specific but introduces a change for all encrypted guests.
^^^^^^^^^^^^

You need to read the whole email.

-- 
Regards/Gruss,
    Boris.

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