Re: [EXTERNAL] Re: [PATCH 4.19 013/247] cifs: Set CIFS_MOUNT_USE_PREFIX_PATH flag on setting cifs_sb->prepath.

From: Greg Kroah-Hartman
Date: Mon May 10 2021 - 03:46:15 EST

Q: Were do I find info about this thing called top-posting?
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing in e-mail?

A: No.
Q: Should I include quotations after my reply?

On Sun, May 09, 2021 at 10:16:06AM +0000, Shyam Prasad wrote:
> Hi Salvatore,
> Thanks for reminding me. I had to do some reading to reply to this one.
> The situation right now is this:
> The patch "cifs: Set CIFS_MOUNT_USE_PREFIX_PATH flag on setting cifs_sb->prepath." has been reverted. Which means that the DFS bug which you originally faced will not be seen.
> Hi Greg,
> Here are the two patches which I'm referring to:
> 1. cifs: Set CIFS_MOUNT_USE_PREFIX_PATH flag on setting cifs_sb->prepath.
> This fixed an issue when two cifs mount points shared a common prefix in the path which they mounted from the same server. The patch was marked for CC:stable considering that this fix can be important for some users.
> However, there was a dependent change for DFS scenario, which is present in the Linus' mainline tree, but were not marked for CC:stable, so missing from the stable trees.
> Due to the missing dependent changes, DFS users faced issues with pre-5.11 kernels, and this patch was reverted in the stable trees.

So, you need that a738c93fb1c1 ("cifs: Set CIFS_MOUNT_USE_PREFIX_PATH
flag on setting cifs_sb->prepath.") merged to where exactly?

> 2. Due to a major change that went into the 5.11 kernel (the new mount API support), the code differs significantly, and the missing patch cannot be applied to pre-5.11 trees.
> Hence, Paulo submitted the attached patch (cifs: fix prefix path in dfs mounts), which fixes this for pre-5.11 kernels.

Can you submit this in a proper format (i.e. not dos line ends, and good
changelog and most importantly, YOUR signed off by on it saying that the
patch came through you?

Make this a 2 patch series please, and be specific as to what tree(s)
this needs to be backported to, and I will be glad to review it.


greg k-h