| Message ID | 1358197093-17823-1-git-send-email-herton.krzesinski@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/fs/splice.c b/fs/splice.c index 7bf08fa..6cb3acb 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -696,8 +696,10 @@ static int pipe_to_sendpage(struct pipe_inode_info *pipe, return -EINVAL; more = (sd->flags & SPLICE_F_MORE) ? MSG_MORE : 0; - if (sd->len < sd->total_len) + + if (sd->len < sd->total_len && pipe->nrbufs > 1) more |= MSG_SENDPAGE_NOTLAST; + return file->f_op->sendpage(file, buf->page, buf->offset, sd->len, &pos, more); }
This is a note to let you know that I have just added a patch titled tcp: fix MSG_SENDPAGE_NOTLAST logic to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Herton ------ From 663ba304005ac179f361078a607ecfec2b88ccc1 Mon Sep 17 00:00:00 2001 From: Eric Dumazet <edumazet@google.com> Date: Sun, 6 Jan 2013 18:21:49 +0000 Subject: [PATCH] tcp: fix MSG_SENDPAGE_NOTLAST logic commit ae62ca7b03217be5e74759dc6d7698c95df498b3 upstream. commit 35f9c09fe9c72e (tcp: tcp_sendpages() should call tcp_push() once) added an internal flag : MSG_SENDPAGE_NOTLAST meant to be set on all frags but the last one for a splice() call. The condition used to set the flag in pipe_to_sendpage() relied on splice() user passing the exact number of bytes present in the pipe, or a smaller one. But some programs pass an arbitrary high value, and the test fails. The effect of this bug is a lack of tcp_push() at the end of a splice(pipe -> socket) call, and possibly very slow or erratic TCP sessions. We should both test sd->total_len and fact that another fragment is in the pipe (pipe->nrbufs > 1) Many thanks to Willy for providing very clear bug report, bisection and test programs. Reported-by: Willy Tarreau <w@1wt.eu> Bisected-by: Willy Tarreau <w@1wt.eu> Tested-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> --- fs/splice.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) -- 1.7.9.5