Hi Trond,

Obviously, the patch is incorrect. The behavior of the upstream kernel and
RHEL kernels are different.

Sorry for the noise,
  Tigran.


----- Original Message -----

From: "Trond Myklebust" <redacted>
To: anna@kernel.org, "Tigran Mkrtchyan" <redacted>
Cc: "linux-nfs" <redacted>
Sent: Thursday, 8 June, 2023 19:53:07
Subject: Re: [PATCH] nfs4: don't map EACCESS and EPERM to EIO

On Thu, 2023-06-08 at 19:42 +0200, Tigran Mkrtchyan wrote:

quoted

Hi Trond,

I will check and let you know. What we see is EACCESS on layoutget
reported as EIO to the applications

If this is for a write, then that might just be
nfs_mapping_set_error(). In newer kernels, it tries to avoid sending
errors that are unexpected for strictly POSIX applications.

Cheers
 Trond

quoted

Best regards,
Tigran


On June 8, 2023 5:33:16 PM GMT+02:00, Trond Myklebust
[off-list ref] wrote:

quoted

Hi Tigran,

On Thu, 2023-06-08 at 16:49 +0200, Tigran Mkrtchyan wrote:

quoted

the nfs4_map_errors function converts NFS specific errors to
userland
errors. However, it ignores NFS4ERR_PERM and EPERM, which then
get
mapped to EIO.

Signed-off-by: Tigran Mkrtchyan
[off-list ref] fs/nfs/nfs4proc.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index d3665390c4cb..795205fe4f30 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c

@@ -171,12 +171,14 @@ static int nfs4_map_errors(int err)

        case -NFS4ERR_LAYOUTTRYLATER:
        case -NFS4ERR_RECALLCONFLICT:
                return -EREMOTEIO;
+       case -NFS4ERR_PERM:
        case -NFS4ERR_WRONGSEC:
        case -NFS4ERR_WRONG_CRED:
                return -EPERM;
        case -NFS4ERR_BADOWNER:
        case -NFS4ERR_BADNAME:
                return -EINVAL;
+       case -NFS4ERR_ACCESS:
        case -NFS4ERR_SHARE_DENIED:
                return -EACCES;
        case -NFS4ERR_MINOR_VERS_MISMATCH:

Hmm... Aren't both these cases covered by the exception at the top
of
the function?

static int nfs4_map_errors(int err)
{
        if (err >= -1000)
                return err;

As I read it, that should mean that err = -NFS4ERR_ACCESS (= -13)
and
err = -NFS4ERR_PERM (= -1) will get returned verbatim.

Are you seeing these NFS4ERR_ACCESS and NFS4ERR_PERM cases hitting
the
default: dprintk() when you turn it on?

--
Trond Myklebust
CTO, Hammerspace Inc
1900 S Norfolk St, Suite 350 - #45
San Mateo, CA 94403

www.hammerspace.com