[xen master] x86/tboot: correct IOMMU (VT-d) interaction

[patchbot@xxxxxxx]

commit 8301856bd956558161aa0c71623c85403ebdca35
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Mon Dec 12 12:21:01 2022 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon Dec 12 12:21:01 2022 +0100

    x86/tboot: correct IOMMU (VT-d) interaction
    
    First of all using is_idle_domain() on the subject domain in the body of
    for_each_domain() is pointless. Replace that conditional by one checking
    that a domain actually has IOMMU support enabled for it, and that we're
    actually on a VT-d system (both are largely cosmetic / documentary with
    how things work elsewhere, but still).
    
    Reported-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Reviewed-by: Jason Andryuk <jandryuk@xxxxxxxxx>
    Reviewed-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
 xen/arch/x86/tboot.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/xen/arch/x86/tboot.c b/xen/arch/x86/tboot.c
index 569732cffe..68bee222dd 100644
--- a/xen/arch/x86/tboot.c
+++ b/xen/arch/x86/tboot.c
@@ -31,6 +31,8 @@ static vmac_t frametable_mac; /* MAC for frame table during 
S3 */
 static uint64_t __initdata txt_heap_base, __initdata txt_heap_size;
 static uint64_t __initdata sinit_base, __initdata sinit_size;
 
+static bool __ro_after_init is_vtd;
+
 /*
  * TXT configuration registers (offsets from TXT_{PUB, PRIV}_CONFIG_REGS_BASE)
  */
@@ -201,7 +203,7 @@ static void tboot_gen_domain_integrity(const uint8_t 
key[TB_KEY_SIZE],
         }
         spin_unlock(&d->page_alloc_lock);
 
-        if ( !is_idle_domain(d) )
+        if ( is_iommu_enabled(d) && is_vtd )
         {
             const struct domain_iommu *dio = dom_iommu(d);
 
@@ -413,6 +415,8 @@ int __init cf_check 
tboot_parse_dmar_table(acpi_table_handler dmar_handler)
     if ( txt_heap_base == 0 )
         return 1;
 
+    is_vtd = true;
+
     /* walk heap to SinitMleData */
     pa = txt_heap_base;
     /* skip BiosData */
--
generated by git-patchbot for /home/xen/git/xen.git#master