[PATCH AUTOSEL 4.20 33/81] drm/radeon: check if device is root before getting pci speed caps

From: Sasha Levin
Date: Thu Feb 28 2019 - 10:09:12 EST


From: Alex Deucher <alexander.deucher@xxxxxxx>

[ 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@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/radeon/ci_dpm.c | 5 +++--
drivers/gpu/drm/radeon/si_dpm.c | 5 +++--
2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/radeon/ci_dpm.c b/drivers/gpu/drm/radeon/ci_dpm.c
index d587779a80b4d..a97294ac96d59 100644
--- 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 8fb60b3af0158..0a785ef0ab660 100644
--- 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 {
--
2.19.1