From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f176.google.com (mail-pf1-f176.google.com [209.85.210.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3CD9C2D12EE for ; Fri, 22 Aug 2025 19:01:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.176 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755889317; cv=none; b=E3SLyes87Q/VXULjszPLkJtD+OYhGhOnx0Xb0ALWCAosPI8Jus/UrBhc2mGa4hCpffTuxktROHkd7XElN93P+ZRd0x8Xji1Fjqb/fR9JDAXZLbzuRorpDDi7k2s85mW4e6RRUezweCOBRC8FPTv5ENy0Bnq00t0kidX1hkmJgzI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755889317; c=relaxed/simple; bh=F6CyFhck5m8cKEPXXRbIJbXQPp2uCDn9sqFms57kv6s=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=qpyvRCdbCGnFqYb8TE1TCUs4Pq53+N2H7Stk0edZRFdRvAOyLB7Xh3C+hM3y5gryX9oPcUggbytPVWkNUAAmEHgqu2L7zVjGYk1FIY2bVNZHc6CP806m9KPYdwIEDCPPvbVymrdX17rvalhLkSDOfbDvP3EqgOoRq/RCvXpgADs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org; spf=pass smtp.mailfrom=chromium.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b=NsPKLLKW; arc=none smtp.client-ip=209.85.210.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="NsPKLLKW" Received: by mail-pf1-f176.google.com with SMTP id d2e1a72fcca58-76e2e6038cfso2843259b3a.0 for ; Fri, 22 Aug 2025 12:01:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1755889315; x=1756494115; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=7qRfJ1efwUt5qzWhi/EksrwXOERx/hksi00iK1a2Is0=; b=NsPKLLKW9A9BeXy7JJeLoIg0ypeA1T44gktEsHtDMCp1zCer9zEMjHXNPkzcbTI68l MXpgClGCAI61FZ+7tDSea19X8cq7ZratyClDgmQynNmf1bGYzr6HwvKkmaKoJ9eNX22a DsKJMMxzCMloR4lRgsKnZdNuMgf2ZKCWM3XAQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1755889315; x=1756494115; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=7qRfJ1efwUt5qzWhi/EksrwXOERx/hksi00iK1a2Is0=; b=i7gCqiK/INkT68L7DNT/ZD627baL1G3kFcwQvHeRkBX8cvtzqenMXbaF69KrDjEp3W nEivHgCTUXwriA7K28ljUrGCFgAUbjO4MyeDHzznEJthz4WhFj9X4dTVLC31apCsJUNx GDLCdpisk+A/PBK0Cor0+eLVWdSHBS/HhRVTiO387red7YfVfc4EF5ATAT2RJ39x4q4b QnVm5HlYxLJEtqbU2EyX4v876g9tl/ztcXgSLKtk4FsOJ0faRxQTHS4wdhd78k4UwGby 8RdPX3uu3FGY+J+6vNDPVvSoGEKc4ESaF5OfzRRtveM2OBZkpggE0P5JHMFWlzmgIkqc X8BQ== X-Forwarded-Encrypted: i=1; AJvYcCWFzM/DmH4q8V5wSAz0BRDzDYHr0pAykHBxCuZM7/3FD0H1+xeDsLQ14e0+q8eXhWFZ6cjrE9DmVeO0EsI=@vger.kernel.org X-Gm-Message-State: AOJu0Yyf7muPF8z83hunOlA4Lprts2ZvRSERJKoZLh1szYWC28Qp+gGr S9c4CCO8eT8sLIvOy2XJZ1hKn1UtF1b+TkoHsq2WVJnNpqtbrdWwzQ++n62Q7K5zMA== X-Gm-Gg: ASbGncsJ5zxuqGVZHCzMkUGCD7G5ywkgoUOFO8GVUVT3RcUi2djlmin/ljA5GdH3rk0 fzM7xPVr3nrc2Dc+CU1U/B8LX5RtemlwkNu9hhyazAtl3J9bk2UDDKOom90qUhB0UcsQgV6F8HH hfnfd9FUUrILeukFNFeqR8sYVhaEsw9rSeHIU+sQr/441mv2oQ9Mv+tm6/LdOC/KzjtoIrgrviA YhDw4FF3e31hHbEkJvN8kGz6uuETEMj+dJ8r7WQel6cIjv7h0EuhoniW2Sf1OrqFdVxghHCpH3B aJTQgV4NuON8BnnBtPBnhWevXmjZa7aVk1i7DAJ+VhLP2hXDOBMn0qF0xBQopzB13n8/dzNHW/h FtAI2XLoRoxAjZzEqCzKvl8XX/cycMJ8pjrrJ6BafUkzWIx2vBdD7ZMftc1Iy+2cO2KrfCw== X-Google-Smtp-Source: AGHT+IERU1thLXYMzICfViuGk8kImPkUJS7xK6VrYeodDoNR/f9WswSi/cDfGBjhN7V5j2ahaOqNhQ== X-Received: by 2002:a05:6a00:2309:b0:76e:99ff:c9f7 with SMTP id d2e1a72fcca58-7702fc0267bmr5221220b3a.22.1755889315318; Fri, 22 Aug 2025 12:01:55 -0700 (PDT) Received: from localhost ([2a00:79e0:2e14:7:154c:8cf:f7d0:c083]) by smtp.gmail.com with UTF8SMTPSA id d2e1a72fcca58-7703ffb48a0sm617048b3a.8.2025.08.22.12.01.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 22 Aug 2025 12:01:54 -0700 (PDT) Date: Fri, 22 Aug 2025 12:01:53 -0700 From: Brian Norris To: Guenter Roeck Cc: Thomas Gleixner , David Gow , linux-kernel@vger.kernel.org, kunit-dev@googlegroups.com Subject: Re: [PATCH 0/6] genirq/test: Platform/architecture fixes Message-ID: References: <20250818192800.621408-1-briannorris@chromium.org> <9bfdbbed-52c1-4c5d-bdc3-963a902f2b4b@roeck-us.net> <2143e074-c82f-4f38-84c7-6a39c6c6ecd3@roeck-us.net> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2143e074-c82f-4f38-84c7-6a39c6c6ecd3@roeck-us.net> On Fri, Aug 22, 2025 at 11:34:04AM -0700, Guenter Roeck wrote: > On 8/21/25 12:06, Brian Norris wrote: > > On Thu, Aug 21, 2025 at 10:02:52AM -0700, Guenter Roeck wrote: > > > Build results: > > > total: 162 pass: 162 fail: 0 > > > Qemu test results: > > > total: 637 pass: 637 fail: 0 > > > Unit test results: > > > pass: 640616 fail: 13 > > > Failed unit tests: > > > arm64:imx8mp-evk:irq_cpuhotplug_test > > > arm64:imx8mp-evk:irq_test_cases > > > m68k:q800:irq_test_cases > > > m68k:virt:irq_test_cases > > > > > > Individual failures: > > > > > > [ 32.613761] # irq_cpuhotplug_test: EXPECTATION FAILED at kernel/irq/irq_test.c:210 > > > [ 32.613761] Expected remove_cpu(1) == 0, but > > > [ 32.613761] remove_cpu(1) == -16 (0xfffffffffffffff0) > > > [ 32.621522] # irq_cpuhotplug_test: EXPECTATION FAILED at kernel/irq/irq_test.c:212 > > > [ 32.621522] Expected add_cpu(1) == 0, but > > > [ 32.621522] add_cpu(1) == 1 (0x1) > > > [ 32.630930] # irq_cpuhotplug_test: pass:0 fail:1 skip:0 total:1 > > > > I managed to get an imx8mp-evk setup running (both little and big > > endian) and couldn't reproduce. But I'm guessing based on the logs that > > we're racing with pci_call_probe(), which disables CPU hotplug > > (cpu_hotplug_disable()) for its duration. > > > > I'm not sure how to handle that. > > > > 1. I could just SKIP the test on EBUSY. But that'd make for flaky test > > coverage. > > 2. Expose some method to block cpu_hotplug_disable() users temporarily. > > 3. Stop trying to do CPU hotplug in a unit test. (It's bordering on > > "integration test"; but it's still useful IMO...) > > 4. Add an EBUSY retry loop? Or some other similar polling (if we had, > > say, a cpu_hotplug_disabled() API). Ah, I see that add_cpu() (cpu_subsys_online()) already has an -EBUSY retry loop, but remove_cpu() doesn't. So #4 seems like a good solution. It might even make sense to retry in cpu_subsys_offline(), rather than just in the test. I'll give this some thought for later though. > Here is an additional data point: It only happens with big endian tests. > This always happens in my setup, and it only happens when booting from > virtio-pci but not when booting from other devices. > > I just re-ran the test and it passed this time, so this is apparently > a flake. I'd suggest to ignore it for now. If I see it again and find > a clean way to reproduce it we can have another look. The emulated PCIe > controller for imx8mp-evk isn't exactly stable, so this may just be a side > effect of emulation problems. This furthers my suspicion that it's a race with PCIe probing. On the failure case, the test is running right after some PCI scan logs. But I'm fine deferring for now, since it's not very reproducible. Brian