From 2efb66af01a08c40bd053e649707803537640c96 Mon Sep 17 00:00:00 2001
From: Sean Christopherson <seanjc@google.com>
Date: Fri, 28 Jul 2023 18:35:11 -0700
Subject: drm/i915/gvt: Put the page reference obtained by KVM's gfn_to_pfn()
Git-commit: 708e49583d7da863898b25dafe4bcd799c414278
Patch-mainline: v6.6-rc1
References: jsc#PED-3527 jsc#PED-5475 jsc#PED-6068 jsc#PED-6070 jsc#PED-6116 jsc#PED-6120 jsc#PED-5065 jsc#PED-5477 jsc#PED-5511 jsc#PED-6041 jsc#PED-6069 jsc#PED-6071
Put the struct page reference acquired by gfn_to_pfn(), KVM's API is that
the caller is ultimately responsible for dropping any reference.
Note, kvm_release_pfn_clean() ensures the pfn is actually a refcounted
struct page before trying to put any references.
Fixes: b901b252b6cf ("drm/i915/gvt: Add 2M huge gtt support")
Reviewed-by: Yan Zhao <yan.y.zhao@intel.com>
Tested-by: Yongwei Ma <yongwei.ma@intel.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Link: https://lore.kernel.org/r/20230729013535.1070024-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/i915/gvt/gtt.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
index f30922c55a0c..5426a27c1b71 100644
--- a/drivers/gpu/drm/i915/gvt/gtt.c
+++ b/drivers/gpu/drm/i915/gvt/gtt.c
@@ -1158,6 +1158,7 @@ static int is_2MB_gtt_possible(struct intel_vgpu *vgpu,
{
const struct intel_gvt_gtt_pte_ops *ops = vgpu->gvt->gtt.pte_ops;
kvm_pfn_t pfn;
+ int ret;
if (!HAS_PAGE_SIZES(vgpu->gvt->gt->i915, I915_GTT_PAGE_SIZE_2M))
return 0;
@@ -1171,7 +1172,9 @@ static int is_2MB_gtt_possible(struct intel_vgpu *vgpu,
if (!pfn_valid(pfn))
return -EINVAL;
- return PageTransHuge(pfn_to_page(pfn));
+ ret = PageTransHuge(pfn_to_page(pfn));
+ kvm_release_pfn_clean(pfn);
+ return ret;
}
static int split_2MB_gtt_entry(struct intel_vgpu *vgpu,
--
2.43.0