Please untag dotnet3.1-3.1.106-1.fc33

[Omair Majid]

Hi,

One of the recent builds produced for "dotnet3.1" for rawhide is broken
on aarch64. It built successfully in koji, but produced aarch64 binaries
that segfault on startup. A new build of dotnet3.1 requires a working
older build. That means all recent builds of dotnet3.1 in Rawhide/F33 on
failed too.

As I understand it, the most recent (broken) build needs to be untagged.
Then a newer build can build using an older (working) build of
dotnet3.1.

This is the broken build:
https://koji.fedoraproject.org/koji/buildinfo?buildID=1544928

I tried it myself, but I don't seem to have permissions:

$ koji untag-build f33 dotnet3.1-3.1.106-1.fc33
2020-08-13 10:11:30,777 [ERROR] koji: ActionNotAllowed: tag requires autosign permission

Thanks,
Omair

--
PGP Key: B157A9F0 (http://pgp.mit.edu/)
Fingerprint = 9DB5 2F0B FD3E C239 E108  E7BD DF99 7AF8 B157 A9F0

[Jeff Law]

On Thu, 2020-08-13 at 10:21 -0400, Omair Majid wrote:
>  Hi,
>  
>  One of the recent builds produced for "dotnet3.1" for rawhide is broken
>  on aarch64. It built successfully in koji, but produced aarch64 binaries
>  that segfault on startup. A new build of dotnet3.1 requires a working
>  older build. That means all recent builds of dotnet3.1 in Rawhide/F33 on
>  failed too.
>  
>  As I understand it, the most recent (broken) build needs to be untagged.
>  Then a newer build can build using an older (working) build of
>  dotnet3.1.
>  
>  This is the broken build:
>  https://koji.fedoraproject.org/koji/buildinfo?buildID=1544928
>  
>  I tried it myself, but I don't seem to have permissions:
>  
>  $ koji untag-build f33 dotnet3.1-3.1.106-1.fc33
>  2020-08-13 10:11:30,777 [ERROR] koji: ActionNotAllowed: tag requires autosign permission
I can't help with the untagging, but I'm here if there's anything going
wrong
with the system tools that is ultimately affecting dotnet.

jeff

[Omair Majid]

Jeff Law <law(a)redhat.com&gt; writes:

>  I can't help with the untagging, but I'm here if there's
> anything
>  going wrong with the system tools that is ultimately affecting dotnet. 
Thanks.

Just for context:

.NET Core uses a bundled (and modified) copy of libunwind for unwinding
the stack. This version doesn't work on aarch64 when built with one of
the new CFLAGS introduced in Fedora 33/34: -mbranch-protection=standard.

The upstream version of libunwind (the Fedora libunwind package) is also
broken (in a completely different way) for aarch64 from a .NET Core
point of view too.

For now, my "fix" is to remove `-mbranch-protection=standard` from
CFLAGS on aarch64 to get things working.

Thanks,
Omair

--
PGP Key: B157A9F0 (http://pgp.mit.edu/)
Fingerprint = 9DB5 2F0B FD3E C239 E108  E7BD DF99 7AF8 B157 A9F0

[Jeff Law]

On Thu, 2020-08-13 at 11:13 -0400, Omair Majid wrote:
>  Jeff Law <law(a)redhat.com&gt; writes:
>  
>  > I can't help with the untagging, but I'm here if there's anything
>  > going wrong with the system tools that is ultimately affecting dotnet.
>  
>  Thanks.
>  
>  Just for context:
>  
>  .NET Core uses a bundled (and modified) copy of libunwind for unwinding
>  the stack. This version doesn't work on aarch64 when built with one of
>  the new CFLAGS introduced in Fedora 33/34: -mbranch-protection=standard.
>  
>  The upstream version of libunwind (the Fedora libunwind package) is also
>  broken (in a completely different way) for aarch64 from a .NET Core
>  point of view too.
>  
>  For now, my "fix" is to remove `-mbranch-protection=standard` from
>  CFLAGS on aarch64 to get things working. 
That may work in the immediate term, but I
think we'll need a better fix in the
long term -- I believe the plan is to have the BTI/PAC stuff enabled by default
for RHEL 9.  We can bug ARM to get upstream libunwind fixed if that would help
(we meet with them Monday -- you'd be welcome to join to provide technical
context to the libunwind issue).

JEff
>

[Kevin Fenzi]

On Thu, Aug 13, 2020 at 09:23:35AM -0600, Jeff Law wrote:
>  On Thu, 2020-08-13 at 11:13 -0400, Omair Majid wrote:
>  > Jeff Law <law(a)redhat.com&gt; writes:
>  > 
>  > > I can't help with the untagging, but I'm here if there's anything
>  > > going wrong with the system tools that is ultimately affecting dotnet.
>  > 
>  > Thanks.
>  > 
>  > Just for context:
>  > 
>  > .NET Core uses a bundled (and modified) copy of libunwind for unwinding
>  > the stack. This version doesn't work on aarch64 when built with one of
>  > the new CFLAGS introduced in Fedora 33/34: -mbranch-protection=standard.
>  > 
>  > The upstream version of libunwind (the Fedora libunwind package) is also
>  > broken (in a completely different way) for aarch64 from a .NET Core
>  > point of view too.
>  > 
>  > For now, my "fix" is to remove `-mbranch-protection=standard` from
>  > CFLAGS on aarch64 to get things working.
>  That may work in the immediate term, but I think we'll need a better fix in the
>  long term -- I believe the plan is to have the BTI/PAC stuff enabled by default
>  for RHEL 9.  We can bug ARM to get upstream libunwind fixed if that would help
>  (we meet with them Monday -- you'd be welcome to join to provide technical
>  context to the libunwind issue). 
FYI for the list: 

We talked about this on irc. We cannot untag that package as it's long
since been shipped out. However, a side tag can be used to build against
the old version:

* create side tag
* tag old version into it
* build new version against old working version. 
* merge side tag

This should allow everything to build and not disrupt all the people who
have the current version already installed, etc. 

kevin