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Date:   Mon, 11 Jul 2022 16:27:13 +0000
Message-Id: <20220711162713.2467476-1-dlatypov@google.com>
Mime-Version: 1.0
Subject: [PATCH] clk: explicitly disable CONFIG_UML_PCI_OVER_VIRTIO in .kunitconfig
From:   Daniel Latypov <dlatypov@google.com>
To:     brendanhiggins@google.com, davidgow@google.com
Cc:     linux-kernel@vger.kernel.org, kunit-dev@googlegroups.com,
        linux-kselftest@vger.kernel.org, skhan@linuxfoundation.org,
        linux-clk@vger.kernel.org, sboyd@kernel.org,
        Daniel Latypov <dlatypov@google.com>,
        Maxime Ripard <maxime@cerno.tech>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

CONFIG_UML_PCI_OVER_VIRTIO=y is needed to enable CONFIG_PCI=y on UML.
However, this causes test failures when running the clk tests, i.e.
$ ./tools/testing/kunit/kunit.py run --kunitconfig=drivers/clk

A snippet of the particular error is:
>     ok 1 - clk_gate_test_parent_rate
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 45 at lib/logic_iomem.c:141 __raw_readl+0x9f/0xd0

This is triggered by this cast in the test:
   143          ctx->fake_mem = (void __force __iomem *)&ctx->fake_reg;
this seems to work except when logic iomem is enabled, i.e.
CONFIG_INDIRECT_IOMEM=y.

As a short-term fix, explicitly disable CONFIG_UML_PCI_OVER_VIRTIO in
drivers/clk/.kunitconfig so we can enable it for everyone else by
default in kunit.py.

The long-term fix probably requires something more complicated, like
  #ifdef CONFIG_INDIRECT_IOMEM
    logic_iomem_add_region(...);
  #endif

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reported-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Maxime Ripard <maxime@cerno.tech>
---
Note: this targeting the -kselftest kunit branch.
There's a commit that triggers this by enabling logic iomem by default
[1] and there's also a commit that lets disable it via kunitconfig file
[2], which this fix relies on.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest.git/commit/?h=kunit&id=6fc3a8636a7b0f7dbd6d0a4e450e765dc17518d4
[2] https://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest.git/commit/?h=kunit&id=8a7c6f859a20ca36a9e3ce71662de697898c9ef5
---
 drivers/clk/.kunitconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/clk/.kunitconfig b/drivers/clk/.kunitconfig
index cdbc7d7deba9..2fbeb71316f8 100644
--- a/drivers/clk/.kunitconfig
+++ b/drivers/clk/.kunitconfig
@@ -2,3 +2,4 @@ CONFIG_KUNIT=y
 CONFIG_COMMON_CLK=y
 CONFIG_CLK_KUNIT_TEST=y
 CONFIG_CLK_GATE_KUNIT_TEST=y
+CONFIG_UML_PCI_OVER_VIRTIO=n

base-commit: 7635778bac7e46458392c1261e3916e8e9e86860
-- 
2.37.0.rc0.161.g10f37bed90-goog