diff --git a/conf/linux_defconfig b/conf/linux_defconfig
index e9b439d..5aa8253 100644
--- a/conf/linux_defconfig
+++ b/conf/linux_defconfig
@@ -4,6 +4,7 @@ CONFIG_HZ_100=y
 CONFIG_PCI=y
 CONFIG_PCI_DEBUG=y
 CONFIG_PCIE_XILINX=y
+CONFIG_PCI_DMA_32=y
 CONFIG_CROSS_COMPILE="riscv64-unknown-linux-gnu-"
 CONFIG_DEFAULT_HOSTNAME="ucbvax"
 # CONFIG_CROSS_MEMORY_ATTACH is not set
diff --git a/conf/linux_framebuffer_smp b/conf/linux_framebuffer_smp
index 3a1ff82..640892a 100644
--- a/conf/linux_framebuffer_smp
+++ b/conf/linux_framebuffer_smp
@@ -73,6 +73,7 @@ CONFIG_ETHERNET=y
 CONFIG_NET_VENDOR_INTEL=y
 CONFIG_E1000E=y
 CONFIG_PCIE_XILINX=y
+CONFIG_PCI_DMA_32=y
 CONFIG_R8169=y
 CONFIG_SCSI=y
 CONFIG_SCSI_DMA=y
diff --git a/linux b/linux
index 79fff5d..7501d87 160000
--- a/linux
+++ b/linux
@@ -1 +1 @@
-Subproject commit 79fff5df660366279664fd4d6b00f6fc5a9637f8
+Subproject commit 7501d87f7ebf8337ab2efa3fe692612a3b845c6f