From nobody Sun Oct 5 01:49:59 2025 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 390621DF98F; Mon, 11 Aug 2025 05:39:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754890794; cv=none; b=LaZgVpVqd745mKJnn+APL9WcFGLYs3to+sO6iF2+yc5L+kK4bW0sIN9eKxiKaSdWWjZa075egOeGeP9Ebfx/Km6Yn/JH/6uzf/ssjcaBrK1xhycgmYAv8vfVeklMM5lYM9wYQDkdAdsZLJYS6A3o6VJV4fWVGM9vL8LQA+/xQbg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754890794; c=relaxed/simple; bh=pnbyQwhaH5zwVvUKdyPprRrHHy4L1oKq2FZOE5FNDD8=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=QXd0nB4bc4d6/cnSXyyxOAZZ4K+/1xaRoxLCqu01wVkSsRj2AaRHtNRwEeBORiBJLIe2A50gFPCu3YTbu14AEvqzaggL8fmw9iTBCJSCc3UfhgzctKfUq5Ch/IXDUxPjjAkVSykCYBWmG3UT/ad4znj6MS01ZlaonegqbgG7+hA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=b9iGjgcf; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=b6TAgw11; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="b9iGjgcf"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="b6TAgw11" From: Nam Cao DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1754890784; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=MJIhtkGvgAsmM0h4kM8I7PSa6klKjzmZORs6f49BmYA=; b=b9iGjgcfDGPemL2W21lMxlQ0pwOKRMzP6HOZtjtKaJGuj1P+bAZPwqaD8JLrFLcRGfqvE8 QbBSWyeSTCO2dRw1E69MPv1amJ4gBapfzM+jXDNemNsiVvgpFVNxJS+6M44HwE92JTR7D5 9MKdCgr73WGlqFeLXIYKQgRNqcee/EeWPiljIEaDfFi/IeZBq0rO4FVxgCKXw105z5d7xG 7BJmeoMCZlc66ZtB5hXtM3ngtdsA0+jwr7Cq70cJBxsQP2660h6zSCfbOt7HKcK34qWuk3 gcLsAIuO0hjzxQdsJUbRh/JDAmePvVN8z9C+KaRGAP2Xk+V2IXkTl4z1KWTbwg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1754890784; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=MJIhtkGvgAsmM0h4kM8I7PSa6klKjzmZORs6f49BmYA=; b=b6TAgw11vXrgWxBP584McGUlXhGR77xJbrjdfKRvFu/GWNKM7Ovmgh3pkvLZ3m0UHcSt7R jFkNqkyBjETbAaDA== To: Nirmal Patel , Jonathan Derrick , Lorenzo Pieralisi , =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= , Manivannan Sadhasivam , Rob Herring , Bjorn Helgaas , Thomas Gleixner , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Nam Cao , Ammar Faizi Subject: [PATCH] PCI: vmd: Remove MSI-X check on child devices Date: Mon, 11 Aug 2025 07:39:35 +0200 Message-Id: <20250811053935.4049211-1-namcao@linutronix.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Commit d7d8ab87e3e7 ("PCI: vmd: Switch to msi_create_parent_irq_domain()") added a WARN_ON sanity check that child devices support MSI-X, because VMD document says [1]: "Intel VMD only supports MSIx Interrupts from child devices and therefore the BIOS must enable PCIe Hot Plug and MSIx interrups [sic]." However, on Ammar's machine, a PCIe port below VMD does not support MSI-X, triggering this WARN_ON. This inconsistency between the document and reality should be investigated further. For now, remove the MSI-X check. Allowing child devices without MSI-X despite what the document says does sound suspicious, but that's what the driver had been doing before the WARN_ON is added. Fixes: d7d8ab87e3e7 ("PCI: vmd: Switch to msi_create_parent_irq_domain()") Link: https://cdrdv2-public.intel.com/776857/VMD_White_Paper.pdf [1] Reported-by: Ammar Faizi Closes: https://lore.kernel.org/linux-pci/aJXYhfc%2F6DfcqfqF@linux.gnuweeb.= org/ Tested-by: Ammar Faizi Signed-off-by: Nam Cao --- drivers/pci/controller/vmd.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c index b679c7f28f51..1bd5bf4a6097 100644 --- a/drivers/pci/controller/vmd.c +++ b/drivers/pci/controller/vmd.c @@ -306,9 +306,6 @@ static bool vmd_init_dev_msi_info(struct device *dev, s= truct irq_domain *domain, struct irq_domain *real_parent, struct msi_domain_info *info) { - if (WARN_ON_ONCE(info->bus_token !=3D DOMAIN_BUS_PCI_DEVICE_MSIX)) - return false; - if (!msi_lib_init_dev_msi_info(dev, domain, real_parent, info)) return false; =20 --=20 2.39.5