Re: [Bug 1847232] [NEW] qemu TCG in s390x mode issue with calculating HASH

[David Hildenbrand]

On 14.10.19 11:53, David Hildenbrand wrote:
> On 08.10.19 16:11, Ivan Warren wrote:
>>
>> On 10/8/2019 3:35 PM, David Hildenbrand wrote:
>>> On 08.10.19 14:11, Cornelia Huck wrote:
>>>> On Tue, 08 Oct 2019 11:19:25 -0000
>>>> Ivan Warren via <address@hidden> wrote:
>>>>
>>>>> Public bug reported:
>>>>>
>>>>> When using go on s390x on Debian x64 (buster) (host) and debian s390x
>>>>> (sid) (guest) I run into the following problem :
>>>>>
>>>>> The following occurs while trying to build a custom project :
>>>>>
>>>>> go: github.com/FactomProject/basen@v0.0.0-20150613233007-fe3947df716e:
>>>>> Get
>>>>> https://proxy.golang.org/github.com/%21factom%21project/basen/@v/v0.0.0-20150613233007-fe3947df716e.mod:
>>>>> local error: tls: bad record MAC
>>>>>
>>>>> Doing a git bisect I find that this problem only occurs on and after
>>>>> commit 08ef92d556c584c7faf594ff3af46df456276e1b
>>>>>
>>>>> Before that commit, all works fine. Past this commit, build always
>>>>> fails.
>>>> What version are you using? Current master?
>>>>
>>>> Can you please share your command line?
>>>>
>>>>> Without any proof, It looks like a hash calculation bug related to using
>>>>> z/Arch vector facilities...
>>>> Not an unreasonable guess, cc:ing David in case he has seen that before.
>>>>
>>> Can you reproduce with "-cpu qemu,vx=off" added to the QEMU command
>>> line? Could be some fallout from vector instruction support. Currently
>>> ill, will have a look when I'm feeling better.
>>
>> Reposted with a reply all... (sorry for the duplicates)
>>
>> So it does !
>>
>>
>> My qemu command line is now (forget the odd funny networking things..)
>>
>> qemu-system-s390x \
>>        -drive
>> file=DEB002.IMG.NEW,discard=unmap,cache=writeback,id=drive-0,if=none \
>>        -device virtio-scsi-ccw,id=virtio-scsi-0 \
>>        -device scsi-hd,id=scsi-hd-0,drive=drive-0 \
>>        -m 8G \
>>        -net nic,macaddr=52:54:00:00:00:02 \
>>        -net tap,ifname=taparm,script=no \
>>        -nographic -accel tcg,thread=multi \
>>        -monitor unix:ms,server,nowait \
>>        -cpu qemu,vx=off \  ##### THAT WAS ADDED as instructed - without it
>> everything goes kaput !
>>        -smp 12
>>
>> And using the latest bleeding edge qemu from github, my build works (the
>> problem goes away).
>>
>> So the z/Arch vector instructions may have a glitch is a venue to
>> consider.. Probably one that couldn't be screened through conventional
>> methods.
>>
>> I'm not that versed into z/Arch vector instruction, but if there
>> anything I can help with, I will !
> 
> I'll have to reproduce, can you outline the steps needed to trigger
> this? (never had to build a go project before #luckyme ( ;) )). It looks
> like https://github.com/FactomProject/basen is getting pulled in from
> some other project?
> 

I just tried with Fedora 31 Nightly using "go get"

[root@f31 ~]# go get -v -d github.com/FactomProject/factom
github.com/FactomProject/factom (download)
github.com/FactomProject/btcutil (download)
github.com/FactomProject/ed25519 (download)
github.com/FactomProject/go-bip32 (download)
github.com/FactomProject/btcutilecc (download)
package golang.org/x/crypto/ripemd160: unrecognized import path 
"golang.org/x/crypto/ripemd160" (https fetch: Get 
https://golang.org/x/crypto/ripemd160?go-get=1: local error: tls: bad record 
MAC)
github.com/FactomProject/go-bip39 (download)
package golang.org/x/crypto/pbkdf2: unrecognized import path 
"golang.org/x/crypto/pbkdf2" (https fetch: Get 
https://golang.org/x/crypto/pbkdf2?go-get=1: local error: tls: bad record MAC)
github.com/FactomProject/go-bip44 (download)
github.com/FactomProject/netki-go-partner-client (download)
github.com/FactomProject/go-simplejson (download)

With vx=off:

[root@f31 ~]# go get -v -d github.com/FactomProject/factom
github.com/FactomProject/factom (download)
github.com/FactomProject/btcutil (download)
github.com/FactomProject/ed25519 (download)
github.com/FactomProject/go-bip32 (download)
github.com/FactomProject/basen (download)
github.com/FactomProject/btcutilecc (download)
get "golang.org/x/crypto/ripemd160": found meta tag 
get.metaImport{Prefix:"golang.org/x/crypto", VCS:"git", 
RepoRoot:"https://go.googlesource.com/crypto"} at 
//golang.org/x/crypto/ripemd160?go-get=1
get "golang.org/x/crypto/ripemd160": verifying non-authoritative meta tag
golang.org/x/crypto (download)
github.com/FactomProject/go-bip39 (download)
github.com/FactomProject/go-bip44 (download)
github.com/FactomProject/netki-go-partner-client (download)
github.com/FactomProject/go-simplejson (download)


That should be sufficient to identify the instruction. Might take some time, 
though. E.g.,
the HASH calculation in the kernel works just fine.

-- 

Thanks,

David / dhildenb