4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexandre Torgue <alexandre.torgue@xxxxxx> [ Upstream commit 224babd62d6f19581757a6d8bae3bf9501fc10de ] GMAC IP is little-endian and used on several kind of CPU (big or little endian). Main callbacks functions of the stmmac drivers take care about it. It was not the case for dwmac4_get_timestamp function. Fixes: ba1ffd74df74 ("stmmac: fix PTP support for GMAC4") Signed-off-by: Alexandre Torgue <alexandre.torgue@xxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c @@ -238,15 +238,18 @@ static inline u64 dwmac4_get_timestamp(v static int dwmac4_rx_check_timestamp(void *desc) { struct dma_desc *p = (struct dma_desc *)desc; + unsigned int rdes0 = le32_to_cpu(p->des0); + unsigned int rdes1 = le32_to_cpu(p->des1); + unsigned int rdes3 = le32_to_cpu(p->des3); u32 own, ctxt; int ret = 1; - own = p->des3 & RDES3_OWN; - ctxt = ((p->des3 & RDES3_CONTEXT_DESCRIPTOR) + own = rdes3 & RDES3_OWN; + ctxt = ((rdes3 & RDES3_CONTEXT_DESCRIPTOR) >> RDES3_CONTEXT_DESCRIPTOR_SHIFT); if (likely(!own && ctxt)) { - if ((p->des0 == 0xffffffff) && (p->des1 == 0xffffffff)) + if ((rdes0 == 0xffffffff) && (rdes1 == 0xffffffff)) /* Corrupted value */ ret = -EINVAL; else