phy: tegra: xusb: Use a bitmask for UTMI pad power state tracking
The current implementation uses bias_pad_enable as a reference count to
manage the shared bias pad for all UTMI PHYs. However, during system
suspension with connected USB devices, multiple power-down requests for
the UTMI pad result in a mismatch in the reference count, which in turn
produces warnings such as:
[ 237.762967] WARNING: CPU: 10 PID: 1618 at tegra186_utmi_pad_power_down+0x160/0x170
[ 237.763103] Call trace:
[ 237.763104] tegra186_utmi_pad_power_down+0x160/0x170
[ 237.763107] tegra186_utmi_phy_power_off+0x10/0x30
[ 237.763110] phy_power_off+0x48/0x100
[ 237.763113] tegra_xusb_enter_elpg+0x204/0x500
[ 237.763119] tegra_xusb_suspend+0x48/0x140
[ 237.763122] platform_pm_suspend+0x2c/0xb0
[ 237.763125] dpm_run_callback.isra.0+0x20/0xa0
[ 237.763127] __device_suspend+0x118/0x330
[ 237.763129] dpm_suspend+0x10c/0x1f0
[ 237.763130] dpm_suspend_start+0x88/0xb0
[ 237.763132] suspend_devices_and_enter+0x120/0x500
[ 237.763135] pm_suspend+0x1ec/0x270
The root cause was traced back to the dynamic power-down changes
introduced in commit a30951d31b25 ("xhci: tegra: USB2 pad power controls"),
where the UTMI pad was being powered down without verifying its current
state. This unbalanced behavior led to discrepancies in the reference
count.
To rectify this issue, this patch replaces the single reference counter
with a bitmask, renamed to utmi_pad_enabled. Each bit in the mask
corresponds to one of the four USB2 PHYs, allowing us to track each pad's
enablement status individually.
With this change:
- The bias pad is powered on only when the mask is clear.
- Each UTMI pad is powered on or down based on its corresponding bit
in the mask, preventing redundant operations.
- The overall power state of the shared bias pad is maintained
correctly during suspend/resume cycles.
The mutex used to prevent race conditions during UTMI pad enable/disable
operations has been moved from the tegra186_utmi_bias_pad_power_on/off
functions to the parent functions tegra186_utmi_pad_power_on/down. This
change ensures that there are no race conditions when updating the bitmask.
Metrics
Affected Vendors & Products
| Source | ID | Title |
|---|---|---|
EUVD |
EUVD-2025-27863 | In the Linux kernel, the following vulnerability has been resolved: phy: tegra: xusb: Use a bitmask for UTMI pad power state tracking The current implementation uses bias_pad_enable as a reference count to manage the shared bias pad for all UTMI PHYs. However, during system suspension with connected USB devices, multiple power-down requests for the UTMI pad result in a mismatch in the reference count, which in turn produces warnings such as: [ 237.762967] WARNING: CPU: 10 PID: 1618 at tegra186_utmi_pad_power_down+0x160/0x170 [ 237.763103] Call trace: [ 237.763104] tegra186_utmi_pad_power_down+0x160/0x170 [ 237.763107] tegra186_utmi_phy_power_off+0x10/0x30 [ 237.763110] phy_power_off+0x48/0x100 [ 237.763113] tegra_xusb_enter_elpg+0x204/0x500 [ 237.763119] tegra_xusb_suspend+0x48/0x140 [ 237.763122] platform_pm_suspend+0x2c/0xb0 [ 237.763125] dpm_run_callback.isra.0+0x20/0xa0 [ 237.763127] __device_suspend+0x118/0x330 [ 237.763129] dpm_suspend+0x10c/0x1f0 [ 237.763130] dpm_suspend_start+0x88/0xb0 [ 237.763132] suspend_devices_and_enter+0x120/0x500 [ 237.763135] pm_suspend+0x1ec/0x270 The root cause was traced back to the dynamic power-down changes introduced in commit a30951d31b25 ("xhci: tegra: USB2 pad power controls"), where the UTMI pad was being powered down without verifying its current state. This unbalanced behavior led to discrepancies in the reference count. To rectify this issue, this patch replaces the single reference counter with a bitmask, renamed to utmi_pad_enabled. Each bit in the mask corresponds to one of the four USB2 PHYs, allowing us to track each pad's enablement status individually. With this change: - The bias pad is powered on only when the mask is clear. - Each UTMI pad is powered on or down based on its corresponding bit in the mask, preventing redundant operations. - The overall power state of the shared bias pad is maintained correctly during suspend/resume cycles. The mutex used to prevent race conditions during UTMI pad enable/disable operations has been moved from the tegra186_utmi_bias_pad_power_on/off functions to the parent functions tegra186_utmi_pad_power_on/down. This change ensures that there are no race conditions when updating the bitmask. |
Ubuntu USN |
USN-7699-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-7699-2 | Linux kernel (HWE) vulnerabilities |
Ubuntu USN |
USN-7721-1 | Linux kernel (Azure) vulnerabilities |
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
Mon, 17 Nov 2025 13:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | NVD-CWE-Other | |
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.15:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.15:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.15:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.15:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.15:rc5:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.15:rc6:*:*:*:*:*:* |
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| Metrics |
cvssV3_1
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cvssV3_1
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Thu, 26 Jun 2025 02:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
cvssV3_1
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cvssV3_1
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Wed, 25 Jun 2025 02:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
cvssV3_1
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cvssV3_1
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Fri, 20 Jun 2025 23:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
Wed, 18 Jun 2025 09:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: phy: tegra: xusb: Use a bitmask for UTMI pad power state tracking The current implementation uses bias_pad_enable as a reference count to manage the shared bias pad for all UTMI PHYs. However, during system suspension with connected USB devices, multiple power-down requests for the UTMI pad result in a mismatch in the reference count, which in turn produces warnings such as: [ 237.762967] WARNING: CPU: 10 PID: 1618 at tegra186_utmi_pad_power_down+0x160/0x170 [ 237.763103] Call trace: [ 237.763104] tegra186_utmi_pad_power_down+0x160/0x170 [ 237.763107] tegra186_utmi_phy_power_off+0x10/0x30 [ 237.763110] phy_power_off+0x48/0x100 [ 237.763113] tegra_xusb_enter_elpg+0x204/0x500 [ 237.763119] tegra_xusb_suspend+0x48/0x140 [ 237.763122] platform_pm_suspend+0x2c/0xb0 [ 237.763125] dpm_run_callback.isra.0+0x20/0xa0 [ 237.763127] __device_suspend+0x118/0x330 [ 237.763129] dpm_suspend+0x10c/0x1f0 [ 237.763130] dpm_suspend_start+0x88/0xb0 [ 237.763132] suspend_devices_and_enter+0x120/0x500 [ 237.763135] pm_suspend+0x1ec/0x270 The root cause was traced back to the dynamic power-down changes introduced in commit a30951d31b25 ("xhci: tegra: USB2 pad power controls"), where the UTMI pad was being powered down without verifying its current state. This unbalanced behavior led to discrepancies in the reference count. To rectify this issue, this patch replaces the single reference counter with a bitmask, renamed to utmi_pad_enabled. Each bit in the mask corresponds to one of the four USB2 PHYs, allowing us to track each pad's enablement status individually. With this change: - The bias pad is powered on only when the mask is clear. - Each UTMI pad is powered on or down based on its corresponding bit in the mask, preventing redundant operations. - The overall power state of the shared bias pad is maintained correctly during suspend/resume cycles. The mutex used to prevent race conditions during UTMI pad enable/disable operations has been moved from the tegra186_utmi_bias_pad_power_on/off functions to the parent functions tegra186_utmi_pad_power_on/down. This change ensures that there are no race conditions when updating the bitmask. | |
| Title | phy: tegra: xusb: Use a bitmask for UTMI pad power state tracking | |
| References |
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-06-18T09:28:20.715Z
Reserved: 2025-04-16T04:51:23.977Z
Link: CVE-2025-38010
No data.
Status : Analyzed
Published: 2025-06-18T10:15:32.283
Modified: 2025-11-17T12:56:38.940
Link: CVE-2025-38010
OpenCVE Enrichment
Updated: 2025-06-23T08:53:47Z
EUVD
Ubuntu USN