drm/radeon: check if device is root before getting pci speed caps

[ Upstream commit afeff4c16edaa6275b903f82b0561406259aa3a3 ]

Check if the device is root rather before attempting to see what
speeds the pcie port supports.  Fixes a crash with pci passthrough
in a VM.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=109366
Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/radeon/ci_dpm.c b/drivers/gpu/drm/radeon/ci_dpm.c
index d587779..a97294a 100644 (file)
--- a/drivers/gpu/drm/radeon/ci_dpm.c
+++ b/drivers/gpu/drm/radeon/ci_dpm.c
@@ -5676,7 +5676,7 @@ int ci_dpm_init(struct radeon_device *rdev)
        u16 data_offset, size;
        u8 frev, crev;
        struct ci_power_info *pi;
-       enum pci_bus_speed speed_cap;
+       enum pci_bus_speed speed_cap = PCI_SPEED_UNKNOWN;
        struct pci_dev *root = rdev->pdev->bus->self;
        int ret;
 
@@ -5685,7 +5685,8 @@ int ci_dpm_init(struct radeon_device *rdev)
                return -ENOMEM;
        rdev->pm.dpm.priv = pi;
 
-       speed_cap = pcie_get_speed_cap(root);
+       if (!pci_is_root_bus(rdev->pdev->bus))
+               speed_cap = pcie_get_speed_cap(root);
        if (speed_cap == PCI_SPEED_UNKNOWN) {
                pi->sys_pcie_mask = 0;
        } else {

diff --git a/drivers/gpu/drm/radeon/si_dpm.c b/drivers/gpu/drm/radeon/si_dpm.c
index 8fb60b3..0a785ef 100644 (file)
--- a/drivers/gpu/drm/radeon/si_dpm.c
+++ b/drivers/gpu/drm/radeon/si_dpm.c
@@ -6899,7 +6899,7 @@ int si_dpm_init(struct radeon_device *rdev)
        struct ni_power_info *ni_pi;
        struct si_power_info *si_pi;
        struct atom_clock_dividers dividers;
-       enum pci_bus_speed speed_cap;
+       enum pci_bus_speed speed_cap = PCI_SPEED_UNKNOWN;
        struct pci_dev *root = rdev->pdev->bus->self;
        int ret;
 
@@ -6911,7 +6911,8 @@ int si_dpm_init(struct radeon_device *rdev)
        eg_pi = &ni_pi->eg;
        pi = &eg_pi->rv7xx;
 
-       speed_cap = pcie_get_speed_cap(root);
+       if (!pci_is_root_bus(rdev->pdev->bus))
+               speed_cap = pcie_get_speed_cap(root);
        if (speed_cap == PCI_SPEED_UNKNOWN) {
                si_pi->sys_pcie_mask = 0;
        } else {