From: Jacob Keller Date: Mon, 8 Jul 2019 23:12:33 +0000 (-0700) Subject: fm10k: cast page_addr to u8 * when incrementing it X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=27429be75e0d291a74b57f9753537e727b7635b7;p=linux.git fm10k: cast page_addr to u8 * when incrementing it The page_addr variable is a void pointer. Incrementing it before calling prefetch is technically undefined. Fix this by casting it to a u8* pointer before incrementing it. This ensures that we increment the pointer value in byte units, instead of relying on this undefined behavior. This was detected by cppcheck, and resolves the following warning produced by that tool: [fm10k_main.c:328]: (portability) 'page_addr' is of type 'void *'. When using void pointers in calculations, the behaviour is undefined. Signed-off-by: Jacob Keller Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher --- diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_main.c b/drivers/net/ethernet/intel/fm10k/fm10k_main.c index 9e6bddff7625d..17a96a49174b3 100644 --- a/drivers/net/ethernet/intel/fm10k/fm10k_main.c +++ b/drivers/net/ethernet/intel/fm10k/fm10k_main.c @@ -315,7 +315,7 @@ static struct sk_buff *fm10k_fetch_rx_buffer(struct fm10k_ring *rx_ring, /* prefetch first cache line of first page */ prefetch(page_addr); #if L1_CACHE_BYTES < 128 - prefetch(page_addr + L1_CACHE_BYTES); + prefetch((void *)((u8 *)page_addr + L1_CACHE_BYTES)); #endif /* allocate a skb to store the frags */