[PATCH] drm/amdgpu: Move read of snoop register from guest to host

[Kasiviswanathan, Harish]

[Public]

One minor comment, with that fixed.

Reviewed-by: Harish Kasiviswanathan <Harish.Kasiviswanathan at amd.com>


-----Original Message-----
From: amd-gfx <amd-gfx-bounces at lists.freedesktop.org> On Behalf Of Masha Grinman
Sent: Monday, April 7, 2025 1:14 PM
To: amd-gfx at lists.freedesktop.org
Cc: Grinman, Masha <Masha.Grinman at amd.com>; Grinman, Masha <Masha.Grinman at amd.com>
Subject: [PATCH] drm/amdgpu: Move read of snoop register from guest to host

From: Masha Grinman <Masha.Grinman at amd.com>

Guest is reading/writing to snoop register which is a security violation
We moved the code to the host driver
And also added a validation on the guest side to check if it's guestwq


[HK]: guestwq <-- is this a typo?

Change-Id: I1d5773ffa6187a961994b3403d4cde5b1641369f
Signed-off-by: Masha Grinman <masha.grinman at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/mmhub_v1_8.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/mmhub_v1_8.c b/drivers/gpu/drm/amd/amdgpu/mmhub_v1_8.c
index a54e7b929295..6dc3896fd61f 100644
--- a/drivers/gpu/drm/amd/amdgpu/mmhub_v1_8.c
+++ b/drivers/gpu/drm/amd/amdgpu/mmhub_v1_8.c
@@ -221,6 +221,9 @@ static void mmhub_v1_8_init_snoop_override_regs(struct amdgpu_device *adev)
        uint32_t distance = regDAGB1_WRCLI_GPU_SNOOP_OVERRIDE -
                            regDAGB0_WRCLI_GPU_SNOOP_OVERRIDE;

+       if (amdgpu_sriov_vf(adev))
+                return;
+
        inst_mask = adev->aid_mask;
        for_each_inst(i, inst_mask) {
                for (j = 0; j < 5; j++) { /* DAGB instances */
--
2.34.1