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Date:   Tue, 8 May 2018 12:15:29 -0400
From:   "bfields@fieldses.org" <bfields@fieldses.org>
To:     Trond Myklebust <trondmy@hammer.space>
Cc:     "syzbot+4b98281f2401ab849f4b@syzkaller.appspotmail.com" 
        <syzbot+4b98281f2401ab849f4b@syzkaller.appspotmail.com>,
        "syzkaller-bugs@googlegroups.com" <syzkaller-bugs@googlegroups.com>,
        "anna.schumaker@netapp.com" <anna.schumaker@netapp.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-nfs@vger.kernel.org" <linux-nfs@vger.kernel.org>,
        "jlayton@kernel.org" <jlayton@kernel.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        Chuck Lever <chucklever@gmail.com>
Subject: Re: general protection fault in encode_rpcb_string
Message-ID: <20180508161529.GD6151@fieldses.org>
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 <20180417213308.GC18217@fieldses.org>
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On Tue, Apr 17, 2018 at 09:54:36PM +0000, Trond Myklebust wrote:
> Yes, and we can probably convert it, and the other GFP_ATOMIC
> allocations in the rpcbind client to use GFP_NOFS in order to improve
> reliability.

Chuck, I think the GFP_ATOMIC is unnecessary here as well?

--b.

diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index e8adad33d0bb..de90c6c90cde 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -228,7 +228,7 @@ rpcrdma_convert_iovs(struct rpcrdma_xprt *r_xprt, struct xdr_buf *xdrbuf,
 			/* XXX: Certain upper layer operations do
 			 *	not provide receive buffer pages.
 			 */
-			*ppages = alloc_page(GFP_ATOMIC);
+			*ppages = alloc_page(GFP_NOFS);
 			if (!*ppages)
 				return -EAGAIN;
 		}