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 A06D8519DE0; Thu, 17 Sep 2026 16:56:15 +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=1789664176; cv=none; b=OZE6TH9uLh4E1v+mUmibrfIJaSsfO+eS6DEcWwo7rU18eSSMY1Es656wOQ5cDr9ygreZFKFsyONXnWPjm18Q2n21H56AqqJX6CwY2DjvjTDxQSjGhRwHYltOc54PCgAHfvbK3jk2TTocJ2Y7iSbRd8HmBBmO8StErgf4QYweADI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789664176; c=relaxed/simple; bh=qpOhW+UKq9YzH+rwEJb03Zal8vaEFozpxVTma+RwwlQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PVsDfW5DjlNc+/fEsB9Qenf/5yytgn0pa6yfjkrVUBgD+5AM0FWxMabV0eYmUU8vLUqcNIqPcccY/qBvMWzhX/Jg4rgEnj80enEL1ZA8GwtWXjCH+X9pULg1fRv48s+cLV77X+lIIyJRoLIchZGZZ2uVuZ6TU7CXqs17ftgpMYo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=osV8ogmc; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="osV8ogmc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 023AE1F000FF; Thu, 17 Sep 2026 16:56:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789664175; bh=3C5s797tBHMrvhKT+VoFeG763FD8++YGWN2hM26VSZs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=osV8ogmcPzVghiUNcepK1mmh4OxpD2M5z7TFjR216M9bQbfu+xpEG9GSnYOp3eV1Y gkp66NfSsLYSauRnGNdq8XTq+d4soF05Tf5I2qk6pehW5SUEWiskd1lPYkjdU8Eney cM7q5eI9wygFc+mG4VDdL9Hr5xNB7ZNC0teAjOCo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Chen Pei , Alison Schofield , "Rafael J. Wysocki" , Sasha Levin Subject: [PATCH 6.18 0283/1250] ACPI: scan: Honor _DEP for ACPI0016 PCI/CXL host bridge Date: Thu, 17 Sep 2026 16:01:18 +0100 Message-ID: <20260917151559.804492162@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260917151551.901433442@linuxfoundation.org> References: <20260917151551.901433442@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chen Pei [ Upstream commit bf5418a5fe63f35da35941ae896d5df121d95ffc ] CXL root devices (ACPI0017) declare _DEP on their parent ACPI0016 PCI/CXL host bridge so that cxl_acpi probes only after acpi_pci_root has attached the PCI root and registered it for acpi_pci_find_root(). However, acpi_dev_ready_for_enumeration() only consults dep_unmet when the supplier's HID is on acpi_honor_dep_ids[]; otherwise the dependency is silently ignored. Without honoring the dependency, cxl_acpi can probe before the PCI root is ready. The resulting CXL topology is broken: decoder targets read as 0 and no port/endpoint devices appear under /sys/bus/cxl/devices/. Add ACPI0016 to acpi_honor_dep_ids[] so the _DEP declared by ACPI0017 is enforced. This relies on the preceding patch ("ACPI: PCI: clear _DEP dependencies after PCI root bridge attach"), which releases the dependency once the PCI root is fully enumerated; the two patches must be applied together. Signed-off-by: Chen Pei Tested-by: Alison Schofield Reviewed-by: Alison Schofield Link: https://patch.msgid.link/20260526025118.38935-3-cp0613@linux.alibaba.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/acpi/scan.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 92928389ea0f9..32fa1c1ded601 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -870,6 +870,7 @@ static const char * const acpi_honor_dep_ids[] = { "RSCV0005", /* RISC-V SBI MPXY MBOX */ "RSCV0006", /* RISC-V RPMI SYSMSI */ "PNP0C0F", /* PCI Link Device */ + "ACPI0016", /* CXL/PCIe host bridge: CXL root (ACPI0017) depends on PCI root attach */ NULL }; -- 2.53.0