net: eth-uclass: guard against reentrant eth_init()/eth_halt() calls
With netconsole, any log message can result in an eth_init(), possibly
causing an reentrant call into eth_init() if a driver's ops print
anything:
eth_init() -> driver.start() -> printf() -> netconsole -> eth_init()
eth_halt() -> driver.stop() -> printf() -> netconsole -> eth_init()
Rather than expecting every single Ethernet driver to handle this case,
prevent the reentrant calls in eth_init() and eth_halt().
The issue was noticed on an AM62x board, where a bootm after
simultaneous netconsole and TFTP would result in a crash.
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Link: https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1350550/sk-am62a-lp-am65_cpsw_nuss_port-error-in-u-boot-while-using-netconsole-functionality/
diff --git a/net/eth-uclass.c b/net/eth-uclass.c
index 4e3933f..e34d7af 100644
--- a/net/eth-uclass.c
+++ b/net/eth-uclass.c
@@ -47,6 +47,8 @@
/* eth_errno - This stores the most recent failure code from DM functions */
static int eth_errno;
+/* Are we currently in eth_init() or eth_halt()? */
+static bool in_init_halt;
/* board-specific Ethernet Interface initializations. */
__weak int board_interface_eth_init(struct udevice *dev,
@@ -284,11 +286,19 @@
int eth_init(void)
{
- char *ethact = env_get("ethact");
- char *ethrotate = env_get("ethrotate");
struct udevice *current = NULL;
struct udevice *old_current;
int ret = -ENODEV;
+ char *ethrotate;
+ char *ethact;
+
+ if (in_init_halt)
+ return -EBUSY;
+
+ in_init_halt = true;
+
+ ethact = env_get("ethact");
+ ethrotate = env_get("ethrotate");
/*
* When 'ethrotate' variable is set to 'no' and 'ethact' variable
@@ -297,8 +307,10 @@
if ((ethrotate != NULL) && (strcmp(ethrotate, "no") == 0)) {
if (ethact) {
current = eth_get_dev_by_name(ethact);
- if (!current)
- return -EINVAL;
+ if (!current) {
+ ret = -EINVAL;
+ goto end;
+ }
}
}
@@ -306,7 +318,8 @@
current = eth_get_dev();
if (!current) {
log_err("No ethernet found.\n");
- return -ENODEV;
+ ret = -ENODEV;
+ goto end;
}
}
@@ -323,7 +336,8 @@
priv->state = ETH_STATE_ACTIVE;
priv->running = true;
- return 0;
+ ret = 0;
+ goto end;
}
} else {
ret = eth_errno;
@@ -343,6 +357,8 @@
current = eth_get_dev();
} while (old_current != current);
+end:
+ in_init_halt = false;
return ret;
}
@@ -351,17 +367,25 @@
struct udevice *current;
struct eth_device_priv *priv;
+ if (in_init_halt)
+ return;
+
+ in_init_halt = true;
+
current = eth_get_dev();
if (!current)
- return;
+ goto end;
priv = dev_get_uclass_priv(current);
if (!priv || !priv->running)
- return;
+ goto end;
eth_get_ops(current)->stop(current);
priv->state = ETH_STATE_PASSIVE;
priv->running = false;
+
+end:
+ in_init_halt = false;
}
int eth_is_active(struct udevice *dev)