From 4e89d629dc72965ea05a9b5231862ffd9c9dab55 Mon Sep 17 00:00:00 2001 From: John Olender Date: Fri, 5 Sep 2025 06:11:28 -0400 Subject: [PATCH] drm/amdgpu: Fix NULL ptr deref in amdgpu_device_cache_switch_state() Kaveri has no upstream bridge, therefore parent is NULL. $ lspci -PP ... 00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Kaveri [Radeon R7 Graphics] (rev d4) For comparison, Raphael: $ lspci -PP ... 00:08.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Raphael/Granite Ridge Internal GPP Bridge to Bus [C:A] ... 00:08.1/0e:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Raphael (rev c5) Fixes: 1dd2fa0e00f1 ("drm/amdgpu: Save and restore switch state") Link: https://lore.kernel.org/amd-gfx/38fe6513-f8a9-4669-8e86-89c54c465611@gmail.com/ Reviewed-by: Candice Li Reviewed-by: Yang Wang Signed-off-by: John Olender Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c index bdfb80377e6a8..b20383021b505 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c @@ -7161,7 +7161,7 @@ static void amdgpu_device_cache_switch_state(struct amdgpu_device *adev) struct pci_dev *parent = pci_upstream_bridge(adev->pdev); int r; - if (parent->vendor != PCI_VENDOR_ID_ATI) + if (!parent || parent->vendor != PCI_VENDOR_ID_ATI) return; /* If already saved, return */ -- 2.47.3