From 9ddc4650a0872715cdc0a5a5dc294fc021ac7bd4 Mon Sep 17 00:00:00 2001
From: Robbe Derks <robbe.derks@gmail.com>
Date: Tue, 5 May 2026 12:43:05 +0200
Subject: [PATCH] don't reboot on wifi SMMU crash (#120)

---
 arch/arm64/configs/tici_defconfig |  2 +-
 drivers/iommu/arm-smmu.c          | 13 ++++++++++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/configs/tici_defconfig b/arch/arm64/configs/tici_defconfig
index 540f95fcbfec..564f7ac87890 100644
--- a/arch/arm64/configs/tici_defconfig
+++ b/arch/arm64/configs/tici_defconfig
@@ -4487,7 +4487,7 @@ CONFIG_MSM_SYSMON_GLINK_COMM=y
 CONFIG_MSM_PIL_SSR_GENERIC=y
 CONFIG_MSM_PIL_MSS_QDSP6V5=y
 CONFIG_ICNSS=y
-CONFIG_ICNSS_DEBUG=y
+# CONFIG_ICNSS_DEBUG is not set
 CONFIG_QCOM_COMMAND_DB=y
 CONFIG_MSM_PERFORMANCE=y
 CONFIG_MSM_CDSP_LOADER=y
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index c3376df44eef..b1df8c4e6e8b 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1545,7 +1545,18 @@ static irqreturn_t arm_smmu_context_fault(int irq, void *dev)
 		}
 		ret = IRQ_NONE;
 		resume = RESUME_TERMINATE;
-		if (!non_fatal_fault) {
+		/* openpilot#35788: the WLAN host (icnss) periodically trips
+		 * this fault during recovery from upstream blips. The original
+		 * BUG() takes down the whole device; for WLAN we'd rather let
+		 * firmware fail the DMA, trigger its own modem-PD SSR through
+		 * icnss, and bring WLAN back ~7s later with the kernel intact.
+		 * All other masters keep the original BUG(). */
+		if (smmu_domain->dev &&
+		    of_device_is_compatible(smmu_domain->dev->of_node,
+					    "qcom,icnss")) {
+			dev_err(smmu->dev,
+				"Unhandled WLAN context fault! (BUG suppressed; awaiting SSR)\n");
+		} else if (!non_fatal_fault) {
 			dev_err(smmu->dev,
 				"Unhandled arm-smmu context fault!\n");
 			BUG();