Merge tag 'pull-more-8.2-fixes-011223-2' of https://gitlab.com/stsquad/qemu into staging

Flaky avocado tests, gdbstub and gitlab tweaks

  - gdbstub, properly halt when QEMU is having IO issues
  - convert skipIf(GITLAB_CI) to skipUnless(QEMU_TEST_FLAKY_TESTS)
  - tag sbsa-ref tests as TCG only
  - build the correct microblaze for avocado-system-ubuntu
  - add optional flaky tests job to CI

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* tag 'pull-more-8.2-fixes-011223-2' of https://gitlab.com/stsquad/qemu:
  gitlab: add optional job to run flaky avocado tests
  gitlab: build the correct microblaze target
  tests/avocado: tag sbsa tests as tcg only
  docs/devel: rationalise unstable gitlab tests under FLAKY_TESTS
  gdbstub: use a better signal when we halt for IO reasons

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

17 files changed, 125 insertions, 43 deletions

diff --git a/.gitlab-ci.d/buildtest.yml b/.gitlab-ci.d/buildtest.yml
index 7f9af83b10..91663946de 100644
--- a/.gitlab-ci.d/buildtest.yml
+++ b/.gitlab-ci.d/buildtest.yml
@@ -41,7 +41,7 @@ build-system-ubuntu:
   variables:
     IMAGE: ubuntu2204
     CONFIGURE_ARGS: --enable-docs
-    TARGETS: alpha-softmmu microblazeel-softmmu mips64el-softmmu
+    TARGETS: alpha-softmmu microblaze-softmmu mips64el-softmmu
     MAKE_CHECK_ARGS: check-build
 
 check-system-ubuntu:
@@ -217,6 +217,36 @@ avocado-system-opensuse:
     MAKE_CHECK_ARGS: check-avocado
     AVOCADO_TAGS: arch:s390x arch:x86_64 arch:aarch64
 
+#
+# Flaky tests. We don't run these by default and they are allow fail
+# but often the CI system is the only way to trigger the failures.
+#
+
+build-system-flaky:
+  extends:
+    - .native_build_job_template
+    - .native_build_artifact_template
+  needs:
+    job: amd64-debian-container
+  variables:
+    IMAGE: debian
+    QEMU_JOB_OPTIONAL: 1
+    TARGETS: aarch64-softmmu arm-softmmu mips64el-softmmu
+      ppc64-softmmu rx-softmmu s390x-softmmu sh4-softmmu x86_64-softmmu
+    MAKE_CHECK_ARGS: check-build
+
+avocado-system-flaky:
+  extends: .avocado_test_job_template
+  needs:
+    - job: build-system-flaky
+      artifacts: true
+  allow_failure: true
+  variables:
+    IMAGE: debian
+    MAKE_CHECK_ARGS: check-avocado
+    QEMU_JOB_OPTIONAL: 1
+    QEMU_TEST_FLAKY_TESTS: 1
+    AVOCADO_TAGS: flaky
 
 # This jobs explicitly disable TCG (--disable-tcg), KVM is detected by
 # the configure script. The container doesn't contain Xen headers so
diff --git a/docs/devel/testing.rst b/docs/devel/testing.rst
index 22218dbedb..bd132306c1 100644
--- a/docs/devel/testing.rst
+++ b/docs/devel/testing.rst
@@ -1371,23 +1371,33 @@ conditions. For example, tests that take longer to execute when QEMU is
 compiled with debug flags. Therefore, the ``AVOCADO_TIMEOUT_EXPECTED`` variable
 has been used to determine whether those tests should run or not.
 
-GITLAB_CI
-^^^^^^^^^
-A number of tests are flagged to not run on the GitLab CI. Usually because
-they proved to the flaky or there are constraints on the CI environment which
-would make them fail. If you encounter a similar situation then use that
-variable as shown on the code snippet below to skip the test:
+QEMU_TEST_FLAKY_TESTS
+^^^^^^^^^^^^^^^^^^^^^
+Some tests are not working reliably and thus are disabled by default.
+This includes tests that don't run reliably on GitLab's CI which
+usually expose real issues that are rarely seen on developer machines
+due to the constraints of the CI environment. If you encounter a
+similar situation then raise a bug and then mark the test as shown on
+the code snippet below:
 
 .. code::
 
-  @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+  # See https://gitlab.com/qemu-project/qemu/-/issues/nnnn
+  @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
   def test(self):
       do_something()
 
-QEMU_TEST_FLAKY_TESTS
-^^^^^^^^^^^^^^^^^^^^^
-Some tests are not working reliably and thus are disabled by default.
-Set this environment variable to enable them.
+You can also add ``:avocado: tags=flaky`` to the test meta-data so
+only the flaky tests can be run as a group:
+
+.. code::
+
+   env QEMU_TEST_FLAKY_TESTS=1 ./pyvenv/bin/avocado \
+      run tests/avocado -filter-by-tags=flaky
+
+Tests should not live in this state forever and should either be fixed
+or eventually removed.
+
 
 Uninstalling Avocado
 ~~~~~~~~~~~~~~~~~~~~
diff --git a/gdbstub/internals.h b/gdbstub/internals.h
index 465c24b36e..5c0c725e54 100644
--- a/gdbstub/internals.h
+++ b/gdbstub/internals.h
@@ -24,6 +24,7 @@ enum {
     GDB_SIGNAL_TRAP = 5,
     GDB_SIGNAL_ABRT = 6,
     GDB_SIGNAL_ALRM = 14,
+    GDB_SIGNAL_STOP = 17,
     GDB_SIGNAL_IO = 23,
     GDB_SIGNAL_XCPU = 24,
     GDB_SIGNAL_UNKNOWN = 143
diff --git a/gdbstub/system.c b/gdbstub/system.c
index 783ac140b9..83fd452800 100644
--- a/gdbstub/system.c
+++ b/gdbstub/system.c
@@ -183,7 +183,7 @@ static void gdb_vm_state_change(void *opaque, bool running, RunState state)
         break;
     case RUN_STATE_IO_ERROR:
         trace_gdbstub_hit_io_error();
-        ret = GDB_SIGNAL_IO;
+        ret = GDB_SIGNAL_STOP;
         break;
     case RUN_STATE_WATCHDOG:
         trace_gdbstub_hit_watchdog();
diff --git a/tests/avocado/boot_linux.py b/tests/avocado/boot_linux.py
index be30dcbd58..7c4769904e 100644
--- a/tests/avocado/boot_linux.py
+++ b/tests/avocado/boot_linux.py
@@ -12,7 +12,7 @@ import os
 
 from avocado_qemu import LinuxTest, BUILD_DIR
 
-from avocado import skipIf
+from avocado import skipUnless
 
 
 class BootLinuxX8664(LinuxTest):
@@ -93,11 +93,13 @@ class BootLinuxPPC64(LinuxTest):
 
     timeout = 360
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_pseries_tcg(self):
         """
         :avocado: tags=machine:pseries
         :avocado: tags=accel:tcg
+        :avocado: tags=flaky
         """
         self.require_accelerator("tcg")
         self.vm.add_args("-accel", "tcg")
@@ -111,11 +113,13 @@ class BootLinuxS390X(LinuxTest):
 
     timeout = 240
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_s390_ccw_virtio_tcg(self):
         """
         :avocado: tags=machine:s390-ccw-virtio
         :avocado: tags=accel:tcg
+        :avocado: tags=flaky
         """
         self.require_accelerator("tcg")
         self.vm.add_args("-accel", "tcg")
diff --git a/tests/avocado/boot_linux_console.py b/tests/avocado/boot_linux_console.py
index 6eab515718..3f0180e1f8 100644
--- a/tests/avocado/boot_linux_console.py
+++ b/tests/avocado/boot_linux_console.py
@@ -15,7 +15,7 @@ import shutil
 
 from avocado import skip
 from avocado import skipUnless
-from avocado import skipIf
+from avocado import skipUnless
 from avocado_qemu import QemuSystemTest
 from avocado_qemu import exec_command
 from avocado_qemu import exec_command_and_wait_for_pattern
@@ -1419,11 +1419,13 @@ class BootLinuxConsole(LinuxKernelTest):
     # This test has a 6-10% failure rate on various hosts that look
     # like issues with a buggy kernel. As a result we don't want it
     # gating releases on Gitlab.
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_sh4_r2d(self):
         """
         :avocado: tags=arch:sh4
         :avocado: tags=machine:r2d
+        :avocado: tags=flaky
         """
         tar_hash = 'fe06a4fd8ccbf2e27928d64472939d47829d4c7e'
         self.vm.add_args('-append', 'console=ttySC1')
diff --git a/tests/avocado/intel_iommu.py b/tests/avocado/intel_iommu.py
index 77635ab56c..f04ee1cf9d 100644
--- a/tests/avocado/intel_iommu.py
+++ b/tests/avocado/intel_iommu.py
@@ -9,10 +9,11 @@
 # later.  See the COPYING file in the top-level directory.
 import os
 
-from avocado import skipIf
+from avocado import skipUnless
 from avocado_qemu import LinuxTest
 
-@skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+@skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
 class IntelIOMMU(LinuxTest):
     """
     :avocado: tags=arch:x86_64
@@ -21,6 +22,7 @@ class IntelIOMMU(LinuxTest):
     :avocado: tags=machine:q35
     :avocado: tags=accel:kvm
     :avocado: tags=intel_iommu
+    :avocado: tags=flaky
     """
 
     IOMMU_ADDON = ',iommu_platform=on,disable-modern=off,disable-legacy=on'
diff --git a/tests/avocado/linux_initrd.py b/tests/avocado/linux_initrd.py
index ba02e5a563..aad5b19bd9 100644
--- a/tests/avocado/linux_initrd.py
+++ b/tests/avocado/linux_initrd.py
@@ -13,7 +13,7 @@ import logging
 import tempfile
 
 from avocado_qemu import QemuSystemTest
-from avocado import skipIf
+from avocado import skipUnless
 
 
 class LinuxInitrd(QemuSystemTest):
@@ -53,9 +53,12 @@ class LinuxInitrd(QemuSystemTest):
                 max_size + 1)
             self.assertRegex(self.vm.get_log(), expected_msg)
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_with_2gib_file_should_work_with_linux_v4_16(self):
         """
+        :avocado: tags=flaky
+
         QEMU has supported up to 4 GiB initrd for recent kernel
         Expect guest can reach 'Unpacking initramfs...'
         """
diff --git a/tests/avocado/machine_aarch64_sbsaref.py b/tests/avocado/machine_aarch64_sbsaref.py
index bdd1efc768..528c7d2934 100644
--- a/tests/avocado/machine_aarch64_sbsaref.py
+++ b/tests/avocado/machine_aarch64_sbsaref.py
@@ -20,6 +20,10 @@ class Aarch64SbsarefMachine(QemuSystemTest):
     """
     :avocado: tags=arch:aarch64
     :avocado: tags=machine:sbsa-ref
+    :avocado: tags=accel:tcg
+
+    As firmware runs at a higher privilege level than the hypervisor we
+    can only run these tests under TCG emulation.
     """
 
     timeout = 180
diff --git a/tests/avocado/machine_aspeed.py b/tests/avocado/machine_aspeed.py
index df31b2a8a8..6fa5459a07 100644
--- a/tests/avocado/machine_aspeed.py
+++ b/tests/avocado/machine_aspeed.py
@@ -18,7 +18,7 @@ from avocado_qemu import exec_command_and_wait_for_pattern
 from avocado_qemu import interrupt_interactive_console_until_pattern
 from avocado_qemu import has_cmd
 from avocado.utils import archive
-from avocado import skipIf
+from avocado import skipUnless
 from avocado import skipUnless
 
 
@@ -311,11 +311,13 @@ class AST2x00MachineSDK(QemuSystemTest, LinuxSSHMixIn):
             self, 'boot', '## Loading kernel from FIT Image')
         self.wait_for_console_pattern('Starting kernel ...')
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_arm_ast2500_evb_sdk(self):
         """
         :avocado: tags=arch:arm
         :avocado: tags=machine:ast2500-evb
+        :avocado: tags=flaky
         """
 
         image_url = ('https://github.com/AspeedTech-BMC/openbmc/releases/'
@@ -329,11 +331,13 @@ class AST2x00MachineSDK(QemuSystemTest, LinuxSSHMixIn):
             self.workdir + '/ast2500-default/image-bmc')
         self.wait_for_console_pattern('nodistro.0 ast2500-default ttyS4')
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_arm_ast2600_evb_sdk(self):
         """
         :avocado: tags=arch:arm
         :avocado: tags=machine:ast2600-evb
+        :avocado: tags=flaky
         """
 
         image_url = ('https://github.com/AspeedTech-BMC/openbmc/releases/'
diff --git a/tests/avocado/machine_mips_malta.py b/tests/avocado/machine_mips_malta.py
index 9bd54518bf..99bee49e9a 100644
--- a/tests/avocado/machine_mips_malta.py
+++ b/tests/avocado/machine_mips_malta.py
@@ -11,7 +11,7 @@ import os
 import gzip
 import logging
 
-from avocado import skipIf
+from avocado import skipUnless
 from avocado import skipUnless
 from avocado.utils import archive
 from avocado_qemu import QemuSystemTest
@@ -101,23 +101,27 @@ class MaltaMachineFramebuffer(QemuSystemTest):
         """
         self.do_test_i6400_framebuffer_logo(1)
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_mips_malta_i6400_framebuffer_logo_7cores(self):
         """
         :avocado: tags=arch:mips64el
         :avocado: tags=machine:malta
         :avocado: tags=cpu:I6400
         :avocado: tags=mips:smp
+        :avocado: tags=flaky
         """
         self.do_test_i6400_framebuffer_logo(7)
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_mips_malta_i6400_framebuffer_logo_8cores(self):
         """
         :avocado: tags=arch:mips64el
         :avocado: tags=machine:malta
         :avocado: tags=cpu:I6400
         :avocado: tags=mips:smp
+        :avocado: tags=flaky
         """
         self.do_test_i6400_framebuffer_logo(8)
 
diff --git a/tests/avocado/machine_rx_gdbsim.py b/tests/avocado/machine_rx_gdbsim.py
index 6cd8704b01..412a7a5089 100644
--- a/tests/avocado/machine_rx_gdbsim.py
+++ b/tests/avocado/machine_rx_gdbsim.py
@@ -10,7 +10,7 @@
 
 import os
 
-from avocado import skipIf
+from avocado import skipUnless
 from avocado_qemu import QemuSystemTest
 from avocado_qemu import exec_command_and_wait_for_pattern
 from avocado_qemu import wait_for_console_pattern
@@ -22,7 +22,8 @@ class RxGdbSimMachine(QemuSystemTest):
     timeout = 30
     KERNEL_COMMON_COMMAND_LINE = 'printk.time=0 '
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_uboot(self):
         """
         U-Boot and checks that the console is operational.
@@ -30,6 +31,7 @@ class RxGdbSimMachine(QemuSystemTest):
         :avocado: tags=arch:rx
         :avocado: tags=machine:gdbsim-r5f562n8
         :avocado: tags=endian:little
+        :avocado: tags=flaky
         """
         uboot_url = ('https://acc.dl.osdn.jp/users/23/23888/u-boot.bin.gz')
         uboot_hash = '9b78dbd43b40b2526848c0b1ce9de02c24f4dcdb'
@@ -46,7 +48,8 @@ class RxGdbSimMachine(QemuSystemTest):
         # FIXME limit baudrate on chardev, else we type too fast
         #exec_command_and_wait_for_pattern(self, 'version', gcc_version)
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_linux_sash(self):
         """
         Boots a Linux kernel and checks that the console is operational.
@@ -54,6 +57,7 @@ class RxGdbSimMachine(QemuSystemTest):
         :avocado: tags=arch:rx
         :avocado: tags=machine:gdbsim-r5f562n7
         :avocado: tags=endian:little
+        :avocado: tags=flaky
         """
         dtb_url = ('https://acc.dl.osdn.jp/users/23/23887/rx-virt.dtb')
         dtb_hash = '7b4e4e2c71905da44e86ce47adee2210b026ac18'
diff --git a/tests/avocado/machine_s390_ccw_virtio.py b/tests/avocado/machine_s390_ccw_virtio.py
index ffd914ded9..26e938c9e9 100644
--- a/tests/avocado/machine_s390_ccw_virtio.py
+++ b/tests/avocado/machine_s390_ccw_virtio.py
@@ -12,7 +12,7 @@
 import os
 import tempfile
 
-from avocado import skipIf
+from avocado import skipUnless
 from avocado_qemu import QemuSystemTest
 from avocado_qemu import exec_command_and_wait_for_pattern
 from avocado_qemu import wait_for_console_pattern
@@ -167,6 +167,7 @@ class S390CCWVirtioMachine(QemuSystemTest):
         :avocado: tags=device:virtio-gpu
         :avocado: tags=device:virtio-crypto
         :avocado: tags=device:virtio-net
+        :avocado: tags=flaky
         """
 
         kernel_url = ('https://archives.fedoraproject.org/pub/archive'
diff --git a/tests/avocado/replay_kernel.py b/tests/avocado/replay_kernel.py
index 53cb7e5091..af086eab08 100644
--- a/tests/avocado/replay_kernel.py
+++ b/tests/avocado/replay_kernel.py
@@ -15,7 +15,7 @@ import logging
 import time
 
 from avocado import skip
-from avocado import skipIf
+from avocado import skipUnless
 from avocado import skipUnless
 from avocado_qemu import wait_for_console_pattern
 from avocado.utils import archive
@@ -82,11 +82,13 @@ class ReplayKernelBase(LinuxKernelTest):
 
 class ReplayKernelNormal(ReplayKernelBase):
 
+    # See https://gitlab.com/qemu-project/qemu/-/issues/2010
     @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test sometimes gets stuck')
     def test_x86_64_pc(self):
         """
         :avocado: tags=arch:x86_64
         :avocado: tags=machine:pc
+        :avocado: tags=flaky
         """
         kernel_url = ('https://archives.fedoraproject.org/pub/archive/fedora'
                       '/linux/releases/29/Everything/x86_64/os/images/pxeboot'
@@ -179,11 +181,13 @@ class ReplayKernelNormal(ReplayKernelBase):
 
         self.run_rr(kernel_path, kernel_command_line, console_pattern, shift=1)
 
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_arm_cubieboard_initrd(self):
         """
         :avocado: tags=arch:arm
         :avocado: tags=machine:cubieboard
+        :avocado: tags=flaky
         """
         deb_url = ('https://apt.armbian.com/pool/main/l/'
                    'linux-5.10.16-sunxi/linux-image-current-sunxi_21.02.2_armhf.deb')
diff --git a/tests/avocado/reverse_debugging.py b/tests/avocado/reverse_debugging.py
index ed04e92bb4..4cce5a5598 100644
--- a/tests/avocado/reverse_debugging.py
+++ b/tests/avocado/reverse_debugging.py
@@ -10,7 +10,7 @@
 import os
 import logging
 
-from avocado import skipIf
+from avocado import skipUnless
 from avocado_qemu import BUILD_DIR
 from avocado.utils import datadrainer
 from avocado.utils import gdb
@@ -206,7 +206,8 @@ class ReverseDebugging_X86_64(ReverseDebugging):
             + self.get_reg_le(g, self.REG_CS) * 0x10
 
     # unidentified gitlab timeout problem
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_x86_64_pc(self):
         """
         :avocado: tags=arch:x86_64
@@ -223,7 +224,8 @@ class ReverseDebugging_AArch64(ReverseDebugging):
     REG_PC = 32
 
     # unidentified gitlab timeout problem
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_aarch64_virt(self):
         """
         :avocado: tags=arch:aarch64
@@ -247,11 +249,13 @@ class ReverseDebugging_ppc64(ReverseDebugging):
     REG_PC = 0x40
 
     # unidentified gitlab timeout problem
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_ppc64_pseries(self):
         """
         :avocado: tags=arch:ppc64
         :avocado: tags=machine:pseries
+        :avocado: tags=flaky
         """
         # SLOF branches back to its entry point, which causes this test
         # to take the 'hit a breakpoint again' path. That's not a problem,
@@ -260,11 +264,13 @@ class ReverseDebugging_ppc64(ReverseDebugging):
         self.reverse_debugging()
 
     # See https://gitlab.com/qemu-project/qemu/-/issues/1992
-    @skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
     def test_ppc64_powernv(self):
         """
         :avocado: tags=arch:ppc64
         :avocado: tags=machine:powernv
+        :avocado: tags=flaky
         """
         self.endian_is_le = False
         self.reverse_debugging()
diff --git a/tests/avocado/smmu.py b/tests/avocado/smmu.py
index b3c4de6bf4..21ff030ca7 100644
--- a/tests/avocado/smmu.py
+++ b/tests/avocado/smmu.py
@@ -9,10 +9,11 @@
 # later.  See the COPYING file in the top-level directory.
 import os
 
-from avocado import skipIf
+from avocado import skipUnless
 from avocado_qemu import LinuxTest, BUILD_DIR
 
-@skipIf(os.getenv('GITLAB_CI'), 'Running on GitLab')
+@skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
+
 class SMMU(LinuxTest):
     """
     :avocado: tags=accel:kvm
@@ -21,6 +22,7 @@ class SMMU(LinuxTest):
     :avocado: tags=machine:virt
     :avocado: tags=distro:fedora
     :avocado: tags=smmu
+    :avocado: tags=flaky
     """
 
     IOMMU_ADDON = ',iommu_platform=on,disable-modern=off,disable-legacy=on'
diff --git a/tests/avocado/tuxrun_baselines.py b/tests/avocado/tuxrun_baselines.py
index c99bea6c0b..a936a3b780 100644
--- a/tests/avocado/tuxrun_baselines.py
+++ b/tests/avocado/tuxrun_baselines.py
@@ -13,7 +13,7 @@ import os
 import time
 import tempfile
 
-from avocado import skip, skipIf
+from avocado import skip, skipUnless
 from avocado_qemu import QemuSystemTest
 from avocado_qemu import exec_command, exec_command_and_wait_for_pattern
 from avocado_qemu import wait_for_console_pattern
@@ -551,7 +551,7 @@ class TuxRunBaselineTest(QemuSystemTest):
                            haltmsg="Requesting system halt")
 
     # Note: some segfaults caused by unaligned userspace access
-    @skipIf(os.getenv('GITLAB_CI'), 'Skipping unstable test on GitLab')
+    @skipUnless(os.getenv('QEMU_TEST_FLAKY_TESTS'), 'Test is unstable on GitLab')
     def test_sh4(self):
         """
         :avocado: tags=arch:sh4
@@ -561,6 +561,7 @@ class TuxRunBaselineTest(QemuSystemTest):
         :avocado: tags=image:zImage
         :avocado: tags=root:sda
         :avocado: tags=console:ttySC1
+        :avocado: tags=flaky
         """
         sums = { "rootfs.ext4.zst" :
                  "3592a7a3d5a641e8b9821449e77bc43c9904a56c30d45da0694349cfd86743fd",