From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5DEC447FB04 for ; Wed, 5 Aug 2026 15:55:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785945311; cv=none; b=p/2TSRv/1pLZ5XVQy2ygORpsStfjtmuKhmkJRiCb9W7hVMxyaEf2ShWcAZ30dMlWOx18tdw4qt+fOeczUYVF2bXie0vaIixm8lEgC9XzByOVbsZ71SM0wtStO3IdJXq+uhI9rP7Fv9/utf5z4QRc+iyn8XrPNgW6nmD4ztQ06xE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785945311; c=relaxed/simple; bh=VCkp5ryVq1A6siNUMMKti6+PcB0fUFEUBdSI/EGQIbY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GPJlhCbZIvROTAXMpuIsxFdAGqg4KLY5aH2mm5XcVDbzjfJ44kQvVOfY43EnG0978Z/VqanJkLuVm1J33t20UbmVyiJ4yMdFZGnwyZ54RwjeMDdSm0xee61qrLu5tw46jp9U08SZeZ6wv3H2Cee2ExEnCMtnNdMZ+qJbOtFXhGQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 Received: by smtp.kernel.org (Postfix) with ESMTPSA id E34231F000E9; Wed, 5 Aug 2026 15:55:09 +0000 (UTC) From: Dave Jiang To: inux-cxl@vger.kernel.org, linux-perf-users@vger.kernel.org Cc: jic23@kernel.org, will@kernel.org, mark.rutland@arm.com, dave@stgolabs.net, robin.murphy@arm.com, icheng@nvidia.com, sashiko-bot@kernel.org, Jonathan Cameron Subject: [PATCH v4 04/11] perf/cxl: Accept an overflow interrupt on MSI message number 0 Date: Wed, 5 Aug 2026 08:54:54 -0700 Message-ID: <20260805155501.1294472-5-dave.jiang@intel.com> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260805155501.1294472-1-dave.jiang@intel.com> References: <20260805155501.1294472-1-dave.jiang@intel.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit cxl_pmu_probe() rejects the PMU when info->irq <= 0, but at that point the field still holds the MSI/MSI-X message number the device signals overflow on, not a Linux virq. That number is 0-based, and -1 means no interrupt support. Message number 0 is valid and pci_irq_vector() takes a 0-based index, so a compliant device signalling on the first vector fails to probe. Reject only the no-interrupt case, matching how the CXL mailbox and event interrupts handle it. Fixes: 5d7107c72796 ("perf: CXL Performance Monitoring Unit driver") Reported-by: sashiko-bot@kernel.org Closes: https://sashiko.dev/#/patchset/20260715191454.459673-1-dave@stgolabs.net?part=1 Assisted-by: Claude:claude-opus-4-8 Reviewed-by: Jonathan Cameron Reviewed-by: Davidlohr Bueso Acked-by: Richard Cheng Signed-off-by: Dave Jiang --- v4: - Move ahead of the info->msi_vec rename so this one-liner stands alone for backporting (Robin). --- drivers/perf/cxl_pmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/perf/cxl_pmu.c b/drivers/perf/cxl_pmu.c index 40741e529d9b..2bebbbe67a0a 100644 --- a/drivers/perf/cxl_pmu.c +++ b/drivers/perf/cxl_pmu.c @@ -873,7 +873,7 @@ static int cxl_pmu_probe(struct device *dev) .capabilities = PERF_PMU_CAP_NO_EXCLUDE, }; - if (info->irq <= 0) + if (info->irq < 0) return -EINVAL; rc = pci_irq_vector(pdev, info->irq); -- 2.54.0