[PATCH rdma-next] RDMA/erdma: restrict the driver to little-endian systems

From: Leon Romanovsky

Date: Thu Aug 06 2026 - 04:55:00 EST


From: Leon Romanovsky <leonro@xxxxxxxxxx>

The eRDMA device interface requires explicit byte ordering, but several
DMA-visible values that should be little-endian remain native-endian.
Command request payloads are copied verbatim, data-path SQE headers are
written without cpu_to_le64(), and kernel doorbell records are assigned
plain u64 values. The command completion path also reads a little-endian
SQE header without conversion.

These paths are byte-swapped on big-endian kernels and can break command
processing during probe. Since complete big-endian support requires
converting every device-visible structure, depend on !CPU_BIG_ENDIAN.

Fixes: ca7fd6cff3b8 ("RDMA/erdma: Add driver to kernel build environment")
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx>
---
RDMA/erdma: restrict the driver to little-endian systems
---
drivers/infiniband/hw/erdma/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/infiniband/hw/erdma/Kconfig b/drivers/infiniband/hw/erdma/Kconfig
index 267fc1f3c42a..745e5551773f 100644
--- a/drivers/infiniband/hw/erdma/Kconfig
+++ b/drivers/infiniband/hw/erdma/Kconfig
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0-only
config INFINIBAND_ERDMA
tristate "Alibaba Elastic RDMA Adapter (ERDMA) support"
- depends on PCI_MSI && 64BIT
+ depends on PCI_MSI && 64BIT && !CPU_BIG_ENDIAN
depends on INFINIBAND_ADDR_TRANS
depends on INFINIBAND_USER_ACCESS
help

---
base-commit: 961ac0f0c5e414abdd6b33fae84b311d9fde0bd0
change-id: 20260806-missing-endianness-conversion-for-64-f0af69246071

Best regards,
--
Leon Romanovsky <leonro@xxxxxxxxxx>