From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752296AbbDTTIX (ORCPT ); Mon, 20 Apr 2015 15:08:23 -0400 Received: from mail-pa0-f49.google.com ([209.85.220.49]:35267 "EHLO mail-pa0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751024AbbDTTIU convert rfc822-to-8bit (ORCPT ); Mon, 20 Apr 2015 15:08:20 -0400 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2098\)) Subject: Re: [PATCH 01/24] lustre: rip the private symlink nesting limit out From: Andreas Dilger In-Reply-To: <1429553588-24764-1-git-send-email-viro@ZenIV.linux.org.uk> Date: Mon, 20 Apr 2015 13:08:16 -0600 Cc: Linus Torvalds , Oleg Drokin , Neil Brown , LKML , Linux Filesystem Mailing List Content-Transfer-Encoding: 8BIT Message-Id: <343FC7D4-20A1-45D7-B86F-1BD2DC21F53A@dilger.ca> References: <20150420181222.GK889@ZenIV.linux.org.uk> <1429553588-24764-1-git-send-email-viro@ZenIV.linux.org.uk> To: Al Viro X-Mailer: Apple Mail (2.2098) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Apr 20, 2015, at 12:12 PM, Al Viro wrote: > > From: Al Viro > > Signed-off-by: Al Viro Al, the patch itself looks good, thanks. However, if this is applied at the start of the series it could allow tests to easily cause a stack overflow during a bisection (I don't think users would see a kernel in the middle of the series). Could this be converted over to checking nd->link_count along with the [02/24] patch until closer to the end of the series when the recursion has been removed? It isn't fatal if that doesn't happen, since this whole series should land at one time and the chance of testing Lustre symlinks right in the middle of the series is low, just something I thought when reviewing the patch. Cheers, Andreas > --- > drivers/staging/lustre/lustre/llite/symlink.c | 15 +++------------ > 1 file changed, 3 insertions(+), 12 deletions(-) > > diff --git a/drivers/staging/lustre/lustre/llite/symlink.c b/drivers/staging/lustre/lustre/llite/symlink.c > index 3711e67..0615f86 100644 > --- a/drivers/staging/lustre/lustre/llite/symlink.c > +++ b/drivers/staging/lustre/lustre/llite/symlink.c > @@ -126,18 +126,9 @@ static void *ll_follow_link(struct dentry *dentry, struct nameidata *nd) > char *symname = NULL; > > CDEBUG(D_VFSTRACE, "VFS Op\n"); > - /* Limit the recursive symlink depth to 5 instead of default > - * 8 links when kernel has 4k stack to prevent stack overflow. > - * For 8k stacks we need to limit it to 7 for local servers. */ > - if (THREAD_SIZE < 8192 && current->link_count >= 6) { > - rc = -ELOOP; > - } else if (THREAD_SIZE == 8192 && current->link_count >= 8) { > - rc = -ELOOP; > - } else { > - ll_inode_size_lock(inode); > - rc = ll_readlink_internal(inode, &request, &symname); > - ll_inode_size_unlock(inode); > - } > + ll_inode_size_lock(inode); > + rc = ll_readlink_internal(inode, &request, &symname); > + ll_inode_size_unlock(inode); > if (rc) { > ptlrpc_req_finished(request); > request = NULL; > -- > 2.1.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html Cheers, Andreas