From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from helcar.hengli.com.au ([209.40.204.226]:39909 "EHLO helcar.hengli.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750730AbcITJvW (ORCPT ); Tue, 20 Sep 2016 05:51:22 -0400 Date: Tue, 20 Sep 2016 17:51:02 +0800 From: Herbert Xu To: Al Viro Cc: torvalds@linux-foundation.org, axboe@kernel.dk, npiggin@gmail.com, linux-fsdevel@vger.kernel.org, netdev@vger.kernel.org, edumazet@google.com Subject: Re: skb_splice_bits() and large chunks in pipe (was Re: xfs_file_splice_read: possible circular locking dependency detected Message-ID: <20160920095102.GA21088@gondor.apana.org.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160919002258.GJ2356@ZenIV.linux.org.uk> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Al Viro wrote: > > * shoved into scatterlist, which gets fed into crypto/*.c machinery. > No way for a pipe_buffer stuff to get there, fortunately, because I would > be very surprised if it works correctly with compound pages and large > ranges in those. FWIW the crypto API has always been supposed to handle SG entries that cross page boundaries. There were a couple of bugs in this area but AFAIK they've all been fixed. Of course I cannot guarantee that every crypto driver also handles it correctly, but at least we have a few test vectors which test the page-crossing case specifically. Cheers, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt