Re: [PATCH 08/13] x86/virt/tdx: Add SEAMCALL wrappers to add TD private pages

From: Edgecombe, Rick P
Date: Tue Jan 14 2025 - 21:02:43 EST


On Tue, 2025-01-14 at 16:49 -0800, Rick Edgecombe wrote:
> Lastly, TD's are not booting for me, with a QEMU error. Still debugging this.

I was able to boot kvm-coco-queue with the below two fixes. I'll glue the TDX
tests back on tomorrow and test further. Regarding the mk_keyed_paddr()
cast/shift issue, Dave had expressed a preference for int over u16 for keyids:
https://lore.kernel.org/kvm/3a32ce4a-b108-4f06-a22d-14e9c2e135f7@xxxxxxxxx/


diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index 201f2e910411..e83f4bac6e9a 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -149,7 +149,7 @@ static inline u64 mk_keyed_paddr(u16 hkid, struct page
*page)

ret = page_to_phys(page);
/* KeyID bits are just above the physical address bits: */
- ret |= hkid << boot_cpu_data.x86_phys_bits;
+ ret |= (u64)hkid << boot_cpu_data.x86_phys_bits;

return ret;
}
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index df6928a62e2d..307b6ee083d0 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -2307,7 +2307,7 @@ static int __tdx_td_init(struct kvm *kvm, struct td_params
*td_params,
struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
cpumask_var_t packages;
struct page **tdcs_pages = NULL;
- struct page *page, *tdr_page;
+ struct page *tdr_page;
int ret, i;
u64 err, rcx;

@@ -2333,7 +2333,7 @@ static int __tdx_td_init(struct kvm *kvm, struct td_params
*td_params,

for (i = 0; i < kvm_tdx->td.tdcs_nr_pages; i++) {
tdcs_pages[i] = alloc_page(GFP_KERNEL);
- if (!page)
+ if (!tdcs_pages[i])
goto free_tdcs;
}