When enabling the interrupt code for the tpm_tis driver we have
noticed some systems have a bios issue causing an interrupt storm to
occur. The issue isn't limited to a single tpm or system manufacturer
so keeping a denylist of systems with the issue isn't optimal. Instead
try to detect the problem occurring, disable interrupts, and revert to
polling when it happens.
Cc: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxx>
Cc: Peter Huewe <peterhuewe@xxxxxx>
Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
Cc: Matthew Garrett <mjg59@xxxxxxxxxx>
Cc: Hans de Goede <hdegoede@xxxxxxxxxx>
Signed-off-by: Jerry Snitselaar <jsnitsel@xxxxxxxxxx>
---
v2: drop tpm_tis specific workqueue and use just system_wq
drivers/char/tpm/tpm_tis_core.c | 27 +++++++++++++++++++++++++++
drivers/char/tpm/tpm_tis_core.h | 2 ++
2 files changed, 29 insertions(+)
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 23b60583928b..72cc8a5a152c 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -24,6 +24,8 @@
#include <linux/wait.h>
#include <linux/acpi.h>
#include <linux/freezer.h>
+#include <linux/workqueue.h>
+#include <linux/kernel_stat.h>
#include "tpm.h"
#include "tpm_tis_core.h"
@@ -745,9 +747,23 @@ static irqreturn_t tis_int_handler(int dummy, void *dev_id)
{
struct tpm_chip *chip = dev_id;
struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+ static bool check_storm = true;
+ static unsigned int check_start;
u32 interrupt;
int i, rc;
+ if (unlikely(check_storm)) {
+ if (!check_start) {
+ check_start = jiffies_to_msecs(jiffies);
+ } else if ((kstat_irqs(priv->irq) > 1000) &&
+ (jiffies_to_msecs(jiffies) - check_start < 500)) {
+ check_storm = false;
+ schedule_work(&priv->storm_work);
+ } else if (jiffies_to_msecs(jiffies) - check_start >= 500) {
+ check_storm = false;
+ }
+ }
+
rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
if (rc < 0)
return IRQ_NONE;
@@ -987,6 +1003,14 @@ static const struct tpm_class_ops tpm_tis = {
.clk_enable = tpm_tis_clkrun_enable,
};
+static void tpm_tis_storm_work(struct work_struct *work)
+{
+ struct tpm_tis_data *priv = container_of(work, struct tpm_tis_data, storm_work);
+
+ disable_interrupts(priv->chip);
+ dev_warn(&priv->chip->dev, "Interrupt storm detected, using polling.\n");
+}
+
int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
const struct tpm_tis_phy_ops *phy_ops,
acpi_handle acpi_dev_handle)
@@ -1003,6 +1027,9 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
if (IS_ERR(chip))
return PTR_ERR(chip);
+ priv->chip = chip;
+ INIT_WORK(&priv->storm_work, tpm_tis_storm_work);
+
#ifdef CONFIG_ACPI
chip->acpi_dev_handle = acpi_dev_handle;
#endif
diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h
index edeb5dc61c95..5630f294dc0c 100644
--- a/drivers/char/tpm/tpm_tis_core.h
+++ b/drivers/char/tpm/tpm_tis_core.h
@@ -95,6 +95,8 @@ struct tpm_tis_data {
u16 clkrun_enabled;
wait_queue_head_t int_queue;
wait_queue_head_t read_queue;
+ struct work_struct storm_work;
+ struct tpm_chip *chip;
const struct tpm_tis_phy_ops *phy_ops;
unsigned short rng_quality;
};
--
2.27.0
