4.20-stable review patch. If anyone has any objections, please let me know. ------------------ From: Trond Myklebust <trondmy@xxxxxxxxx> commit 6a829eb8619fbdde6d7d627ad582fe119805f39d upstream. After receiving data into the page cache, we need to call flush_dcache_page() for the architectures that define it. Fixes: 277e4ab7d530b ("SUNRPC: Simplify TCP receive code by switching...") Reported-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx # v4.20 Tested-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/sunrpc/xprtsock.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -48,6 +48,7 @@ #include <net/udp.h> #include <net/tcp.h> #include <linux/bvec.h> +#include <linux/highmem.h> #include <linux/uio.h> #include <trace/events/sunrpc.h> @@ -380,6 +381,26 @@ xs_read_discard(struct socket *sock, str return sock_recvmsg(sock, msg, flags); } +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE +static void +xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek) +{ + struct bvec_iter bi = { + .bi_size = count, + }; + struct bio_vec bv; + + bvec_iter_advance(bvec, &bi, seek & PAGE_MASK); + for_each_bvec(bv, bvec, bi, bi) + flush_dcache_page(bv.bv_page); +} +#else +static inline void +xs_flush_bvec(const struct bio_vec *bvec, size_t count, size_t seek) +{ +} +#endif + static ssize_t xs_read_xdr_buf(struct socket *sock, struct msghdr *msg, int flags, struct xdr_buf *buf, size_t count, size_t seek, size_t *read) @@ -413,6 +434,7 @@ xs_read_xdr_buf(struct socket *sock, str seek + buf->page_base); if (ret <= 0) goto sock_err; + xs_flush_bvec(buf->bvec, ret, seek + buf->page_base); offset += ret - buf->page_base; if (offset == count || msg->msg_flags & (MSG_EOR|MSG_TRUNC)) goto out;