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charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit On 01-10-2026 17:37, sashiko-bot@kernel.org wrote: >> +static ssize_t amc_alert_reason_show(struct device *dev, >> + struct device_attribute *attr, char *buf) >> +{ >> + struct xe_device *xe = pdev_to_xe_device(to_pci_dev(dev)); >> + struct xe_amc *amc = xe->i2c->amc; >> + u8 alert_reason; >> + >> + if (!amc->alert_seen) > [Severity: Medium] > Could this read of amc->alert_seen cause a data race? > > The sysfs reader relies on this boolean flag to decide whether to read > alert_reason, but it lacks memory barriers or READ_ONCE(). A concurrent > sysfs reader might observe an inconsistent state here while a new alert > is being processed. |alert_seen is not intended as a synchronization mechanism. It only distinguishes the initial state where no AMC alert has been received. | |The sysfs attribute is expected to be queried after the device is declared wedged, by which point the alert state has already been recorded.| --------------ACJrzUNiqPdzZJLK158E001s Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: 8bit


On 01-10-2026 17:37, sashiko-bot@kernel.org wrote:
+static ssize_t amc_alert_reason_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct xe_device *xe = pdev_to_xe_device(to_pci_dev(dev));
+	struct xe_amc *amc = xe->i2c->amc;
+	u8 alert_reason;
+
+	if (!amc->alert_seen)

[Severity: Medium]
Could this read of amc->alert_seen cause a data race?

The sysfs reader relies on this boolean flag to decide whether to read
alert_reason, but it lacks memory barriers or READ_ONCE(). A concurrent
sysfs reader might observe an inconsistent state here while a new alert
is being processed.
alert_seen is not intended as a synchronization mechanism. It only distinguishes the initial state where no AMC alert has been received. 
The sysfs attribute is expected to be queried after the device is declared wedged, by which point the alert state has already been recorded.

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