According to GDMA protocol, holes (zeros) are allowed at the beginning or middle of the gdma_list_devices_resp message. The existing code cannot properly handle this, and may miss some devices in the list.

To fix, scan the entire list until the num_of_devs are found, or until the end of the list.

Cc: stable@vger.kernel.org Fixes: ca9c54d2d6a5 ("net: mana: Add a driver for Microsoft Azure Network Adapter (MANA)") Signed-off-by: Haiyang Zhang haiyangz@microsoft.com Reviewed-by: Long Li longli@microsoft.com Reviewed-by: Shradha Gupta shradhagupta@microsoft.com --- v2: Fix alignment, extra dmesg.

--- drivers/net/ethernet/microsoft/mana/gdma_main.c | 14 ++++++++++---- include/net/mana/gdma.h | 11 +++++++---- 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c b/drivers/net/ethernet/microsoft/mana/gdma_main.c index c15a5ef4674e..af63d844b3bc 100644 --- a/drivers/net/ethernet/microsoft/mana/gdma_main.c +++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c @@ -134,9 +134,10 @@ static int mana_gd_detect_devices(struct pci_dev *pdev) struct gdma_list_devices_resp resp = {}; struct gdma_general_req req = {}; struct gdma_dev_id dev; - u32 i, max_num_devs; + int found_dev = 0; u16 dev_type; int err; + u32 i;

mana_gd_init_req_hdr(&req.hdr, GDMA_LIST_DEVICES, sizeof(req), sizeof(resp)); @@ -148,12 +149,17 @@ static int mana_gd_detect_devices(struct pci_dev *pdev) return err ? err : -EPROTO; }

- max_num_devs = min_t(u32, MAX_NUM_GDMA_DEVICES, resp.num_of_devs); - - for (i = 0; i < max_num_devs; i++) { + for (i = 0; i < GDMA_DEV_LIST_SIZE && + found_dev < resp.num_of_devs; i++) { dev = resp.devs[i]; dev_type = dev.type;

+ /* Skip empty devices */ + if (dev.as_uint32 == 0) + continue; + + found_dev++; + /* HWC is already detected in mana_hwc_create_channel(). */ if (dev_type == GDMA_DEVICE_HWC) continue; diff --git a/include/net/mana/gdma.h b/include/net/mana/gdma.h index 90f56656b572..62e9d7673862 100644 --- a/include/net/mana/gdma.h +++ b/include/net/mana/gdma.h @@ -408,8 +408,6 @@ struct gdma_context { struct gdma_dev mana_ib; };

-#define MAX_NUM_GDMA_DEVICES 4 - static inline bool mana_gd_is_mana(struct gdma_dev *gd) { return gd->dev_id.type == GDMA_DEVICE_MANA; @@ -556,11 +554,15 @@ enum { #define GDMA_DRV_CAP_FLAG_1_HWC_TIMEOUT_RECONFIG BIT(3) #define GDMA_DRV_CAP_FLAG_1_VARIABLE_INDIRECTION_TABLE_SUPPORT BIT(5)

+/* Driver can handle holes (zeros) in the device list */ +#define GDMA_DRV_CAP_FLAG_1_DEV_LIST_HOLES_SUP BIT(11) + #define GDMA_DRV_CAP_FLAGS1 \ (GDMA_DRV_CAP_FLAG_1_EQ_SHARING_MULTI_VPORT | \ GDMA_DRV_CAP_FLAG_1_NAPI_WKDONE_FIX | \ GDMA_DRV_CAP_FLAG_1_HWC_TIMEOUT_RECONFIG | \ - GDMA_DRV_CAP_FLAG_1_VARIABLE_INDIRECTION_TABLE_SUPPORT) + GDMA_DRV_CAP_FLAG_1_VARIABLE_INDIRECTION_TABLE_SUPPORT | \ + GDMA_DRV_CAP_FLAG_1_DEV_LIST_HOLES_SUP)

#define GDMA_DRV_CAP_FLAGS2 0

@@ -621,11 +623,12 @@ struct gdma_query_max_resources_resp { }; /* HW DATA */

/* GDMA_LIST_DEVICES */ +#define GDMA_DEV_LIST_SIZE 64 struct gdma_list_devices_resp { struct gdma_resp_hdr hdr; u32 num_of_devs; u32 reserved; - struct gdma_dev_id devs[64]; + struct gdma_dev_id devs[GDMA_DEV_LIST_SIZE]; }; /* HW DATA */

/* GDMA_REGISTER_DEVICE */