Ah, thanks Werner, I'll keep that in mind.

This seems to have regressed musl support, per https://bugs.gentoo.org/925443.

Fixed in libksba 1.6.6.

Fixed in npth 1.7.

No, hardware barrier is not needed here. Compiler barrier is used here to prevent optimization removing mask generation and usage in following constant-time code.

Clarification from Dave:

Thanks, I can confirm that this patch fixes the issue. I'll let Sam decide if this is how we want to handle it downstream or wait for confirmation from gcc.

So after taking this down to where it was only patching status.h and mainproc.c to add a write_status_output() I realized the whole issue is down to status-codes.h not being updated automatically if you apply a patch to status.h in a released version.

Having looked at the build log again after applying the patch, I see the first test failing is

Although I don't think this is the case here one should be aware that tests mail fail due to global configuration of GnuPG (/etc/gnupg/*.conf). There is no easy way so solve this except for running a per-test local installation of GnuPG using the gpgconf.ctl feature.

You can get more information by applying a patch below (and also tests/json/Makefile.in):

diff --git a/tests/json/Makefile.am b/tests/json/Makefile.am
index 90fba79e..7523bb6b 100644
--- a/tests/json/Makefile.am
+++ b/tests/json/Makefile.am
@@ -106,6 +106,8 @@ gpg-agent.conf:
 # a key from a smartcard reader (error might be: Unusable secret key)
 	echo pinentry-program $(abs_srcdir)/../gpg/pinentry > ./gpg-agent.conf
 	echo disable-scdaemon >> ./gpg-agent.conf
+	echo debug-all >> ./gpg-agent.conf
+	echo log-file /tmp/gpg-agent-logfile.log >> ./gpg-agent.conf

T4820 is not related (it's a failure of t-keylist-secret in t-json), while this is failure of t-decrypt.

It looks like computation for NIST P-256 failed on hppa (32-bit big-endian, actually running on 64-bit machine, IIUC).
powerpc is similar (32-bit big-endian, actually running on 64-bit machine), but no failures.

Oh wow. It seems you have already coded the feature request. I didn't want to generate work for you and offered to submit a patch. Not that I am complaining.;-) Thank you!

cc @jukivili @gniibe

I think we should separate this into two tasks:

For better action names see T6420: Kleopatra: improve layout of and text in smartcard management view.

Arghh, a GPGME_DEBUG=3 which shows basic I/O preparation does not exhibit the bug.

Fixing gpg is easy but there is some bug lingering in gpgme which might be a recent regression. An strace shows

Those options where originally intended for debugging but your suggestion makes sense. I also add this to most other tools.

At the failed attempt I notice a DEVINFO_STATUS removal soon after the SWITCHCARD. This is related to the reader status file and triggered by ccid_slot_status. --debug ipc.app,reader might be a better selection of debug flags here.

For VSD there should at least no info message be shown - which has to be clicked away - when keyserver is set to "None"