[Discuss] Linux on Lenovo P70 -- data corruption

[rlk at alum.mit.edu (Robert Krawitz)]

On Mon, 4 Sep 2017 13:59:48 -0400, Frank DiPrete wrote:
> What us the NIC in the laptop ?
> I've had this problem before using the open source driver for a network
> adapter.
> (trying to remember which one)

But this appears to also happen over the loopback interface.

> -----Original Message-----
> From: Discuss [mailto:discuss-bounces+fdiprete=comcast.net at blu.org] On
> Behalf Of Robert Krawitz
> Sent: Monday, September 04, 2017 1:12 PM
> To: discuss at blu.org
> Subject: [Discuss] Linux on Lenovo P70 -- data corruption
>
> I'm about at my wit's end here.
>
> I bought a Lenovo P70 on eBay to run Linux on.  But I'm finding some data
> corruption on network data transfers (e. g. scp, ftp, socat).
> The oddity is that in the received files the bytes that are bad always have
> 011111 in the low 6 bits of their address.  There's some clustering, but not
> tight clustering and not at regular intervals.
>
> rsync sometimes reports protocol failures (in either direction -- from this
> machine to something else or from another system to this).  The other system
> is good.  scp/ssh don't report any such problems.
>
> It appears that this is more severe under heavy traffic, and perhaps under
> heavy load too.
>
> Unfortunately, I'm not able (yet) to reproduce this under Windows using
> either ftp or scp, with various background loads.  The addresses in suggest
> that something's going wrong with writing the data out to disk (particularly
> with scp, I'd expect errors to propagate with encryption or to get outright
> protocol failures), but the protocol failures with rsync suggest that it's
> somewhere else.
>
> I get no problems with either memtest86 or Lenovo diags, and prime95 also
> isn't reporting any issues.  This happens under both Knoppix
> 7.7.1 and openSUSE 42.3, the latter with any of the stock kernel, the
> 4.12.9+SUSE kernel, or the 4.12.9 vanilla kernel.
>
> If I can reproduce the problem under Windows, the seller will refund me in
> full and send it back to Lenovo.  If I can't, at best I'll have to pay a 15%
> restocking fee on a not-inexpensive system.  If I try to send it to Lenovo
> under warranty, I expect I'll get an NPF and just waste a lot of time and
> yet another shipping fee.
>
> The system has a Xeon E3-1505Mv5, nVidia M4000M (doesn't matter if X is
> running or not), 32 GB RAM (yes, I've tried each of the two DIMMs
> separately, in different slots), 4K display, two separate eSATA M.2 SSD's.
> The BIOS is up to date with the hyperthreading fix, and in any event it
> happens even if I turn hyperthreading off.  Right now it's an expensive
> white elephant.
>
> Any thoughts?


-- 
Robert Krawitz                                     <rlk at alum.mit.edu>

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