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charset="utf-8" Make amdvi_get_pte_entry() return an error value (-1) in cases where the memory read fails, versus the current return of 0 to indicate failure. The reason is that 0 is also a valid value to have stored in the PTE in guest memory i.e. the guest does not have a mapping. Before this change, amdvi_get_pte_entry() returned 0 for both an error and for empty PTEs, but the page walker implementation that will be introduced in upcoming changes needs a method to differentiate between the two scenarios. Signed-off-by: Alejandro Jimenez --- hw/i386/amd_iommu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c index dc7531fd4a8b9..29ed3f0ef292e 100644 --- a/hw/i386/amd_iommu.c +++ b/hw/i386/amd_iommu.c @@ -528,7 +528,7 @@ static inline uint64_t amdvi_get_pte_entry(AMDVIState *= s, uint64_t pte_addr, &pte, sizeof(pte), MEMTXATTRS_UNSPECIFIED)) { trace_amdvi_get_pte_hwerror(pte_addr); amdvi_log_pagetab_error(s, devid, pte_addr, 0); - pte =3D 0; + pte =3D (uint64_t)-1; return pte; } =20 @@ -1081,7 +1081,7 @@ static void amdvi_page_walk(AMDVIAddressSpace *as, ui= nt64_t *dte, /* add offset and load pte */ pte_addr +=3D ((addr >> (3 + 9 * level)) & 0x1FF) << 3; pte =3D amdvi_get_pte_entry(as->iommu_state, pte_addr, as->dev= fn); - if (!pte) { + if (!pte || (pte =3D=3D (uint64_t)-1)) { return; } oldlevel =3D level; --=20 2.43.5