wifi: iwlwifi: mvm: limit pseudo-D3 to 60 seconds

With unlimited pseudo-D3, we can get stuck here in the read if
the firmware never wakes up. All of our testing infrastructure
however will anyway give up after at most a minute, so there's
no value in that.

Limit this to about a minute to avoid getting stuck with the
RTNL held forever, which basically makes the machine unusable
and then we can't even understand what caused the failure.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240205211151.ca55b3a7fa8d.Id746846f187442ebc689416d2688f2bd9278c0e9@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/intel/iwlwifi/mvm/d3.c

@@ -3389,6 +3389,7 @@ static ssize_t iwl_mvm_d3_test_read(struct file *file, char __user *user_buf,
 				    size_t count, loff_t *ppos)
 {
 	struct iwl_mvm *mvm = file->private_data;
+	unsigned long end = jiffies + 60 * HZ;
 	u32 pme_asserted;
 
 	while (true) {
@@ -3402,6 +3403,12 @@ static ssize_t iwl_mvm_d3_test_read(struct file *file, char __user *user_buf,
 
 		if (msleep_interruptible(100))
 			break;
+
+		if (time_is_before_jiffies(end)) {
+			IWL_ERR(mvm,
+				"ending pseudo-D3 with timeout after ~60 seconds\n");
+			return -ETIMEDOUT;
+		}
 	}
 
 	return 0;