tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: fb893de323e2d39f7a1f6df425703a2edbdf56ea commit: 05933aac7b11911955de307a329dc2a7a14b7bd0 ia64: remove now unused machvec indirections date: 12 months ago config: ia64-randconfig-m031-20200811 (attached as .config) compiler: ia64-linux-gcc (GCC) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; smatch warnings: drivers/net/ethernet/stmicro/stmmac/dwmac_lib.c:224 dwmac_dma_flush_tx_fifo() warn: this loop depends on readl() succeeding vim +224 drivers/net/ethernet/stmicro/stmmac/dwmac_lib.c aec7ff27814528 drivers/net/stmmac/dwmac_lib.c Giuseppe CAVALLARO 2010-01-06 218 ad01b7d480a4a1 drivers/net/stmmac/dwmac_lib.c Giuseppe CAVALLARO 2010-08-23 219 void dwmac_dma_flush_tx_fifo(void __iomem *ioaddr) 688911c2f5e5e4 drivers/net/stmmac/dwmac_lib.c Giuseppe CAVALLARO 2010-04-13 220 { 688911c2f5e5e4 drivers/net/stmmac/dwmac_lib.c Giuseppe CAVALLARO 2010-04-13 221 u32 csr6 = readl(ioaddr + DMA_CONTROL); 688911c2f5e5e4 drivers/net/stmmac/dwmac_lib.c Giuseppe CAVALLARO 2010-04-13 222 writel((csr6 | DMA_CONTROL_FTF), ioaddr + DMA_CONTROL); 688911c2f5e5e4 drivers/net/stmmac/dwmac_lib.c Giuseppe CAVALLARO 2010-04-13 223 688911c2f5e5e4 drivers/net/stmmac/dwmac_lib.c Giuseppe CAVALLARO 2010-04-13 @224 do {} while ((readl(ioaddr + DMA_CONTROL) & DMA_CONTROL_FTF)); 688911c2f5e5e4 drivers/net/stmmac/dwmac_lib.c Giuseppe CAVALLARO 2010-04-13 225 } aec7ff27814528 drivers/net/stmmac/dwmac_lib.c Giuseppe CAVALLARO 2010-01-06 226 :::::: The code at line 224 was first introduced by commit :::::: 688911c2f5e5e4f33b5a1c32839184f1fdf814ee stmmac: fix Transmit FIFO flush operation :::::: TO: Giuseppe CAVALLARO <peppe.cavallaro(a)st.com&gt; :::::: CC: David S. Miller <davem(a)davemloft.net&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org