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 B2F83424658; Thu, 16 Jul 2026 13:41:53 +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=1784209314; cv=none; b=rRkXeuXjioEmw3Iu2CyPbqk/4T0cvQi/atC+9VYaMmxm5Kg0RjzKxvTEjndOIZgLdgWfOXGJQchd0aSbl3rJj+tj1rb6UFuxr449VWVbpevuyzBjVYAtSCLlp6QLkWRD9hp36gKn/JDygIo1I0TqfJR7C9+Hv4nbKYD2fgdNxKo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784209314; c=relaxed/simple; bh=YjECNBh0TofCK4QbQkDnqVq4cwq/m1ORttaEAsflHEQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AnYqO7NmjtULNXDgmqXwf+b9h3iB+VlVkjeOXz/IKz3UE3HHc6eXwXv3/AKaRsWj2WHYn7zbcRAVxCK9s0nQZyWXUSSMHJWRZ//wju3/rM05AU9GGwFA2NgvM+CmCSqPIRg8VMXfGiHWGnBSRAzcTBVVQBo3dGp0H71r6UCCFeU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=yQDIFLRW; 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="yQDIFLRW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 181C41F00A3A; Thu, 16 Jul 2026 13:41:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784209313; bh=fI7K+Qe1ZSJk2FOtArJs3ZM6BEO8v5ELghez7wS9gOs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=yQDIFLRWNdghiZoNjCjs2z1Szum/MybrhmFIJdfvVKAXImoYlsSiIrC/MHEakIFvr xyHPVBoO2vzg6OY1ohPpOOWRZNksGgdnQC+CSEgvPKvXDpnhXzEiLAjVQnDen7QU7m wyAL5poE/c2pWS4mtDiylG7AzPORmflGBcOmP9bA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Marco Nenciarini , Bjorn Helgaas Subject: [PATCH 7.1 138/518] PCI: Skip Resizable BAR restore on read error Date: Thu, 16 Jul 2026 15:26:46 +0200 Message-ID: <20260716133050.873079508@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260716133047.772246337@linuxfoundation.org> References: <20260716133047.772246337@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 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marco Nenciarini commit ee7471fe968d210939be9046089a924cd23c8c3b upstream. pci_restore_rebar_state() uses the Resizable BAR Control register to decide how many BARs to restore (nbars) and which BAR each iteration addresses (bar_idx). When a device does not respond, config reads typically return PCI_ERROR_RESPONSE (~0). Both fields are 3 bits wide, so nbars and bar_idx both evaluate to 7, past the spec's valid ranges for both fields. pci_resource_n() then returns an unrelated resource slot, whose size is used to derive a nonsensical value written back to the Resizable BAR Control register. Bail out if any Resizable BAR Control read returns PCI_ERROR_RESPONSE. No further BARs are touched, which is safe because a config read that returns PCI_ERROR_RESPONSE indicates the device is unreachable and restoration is pointless. Fixes: d3252ace0bc6 ("PCI: Restore resized BAR state on resume") Signed-off-by: Marco Nenciarini Signed-off-by: Bjorn Helgaas Cc: stable@vger.kernel.org Link: https://patch.msgid.link/666cac19b5daa0ab0e0ab64454e76b4d24465dbd.1776429882.git.mnencia@kcore.it Signed-off-by: Greg Kroah-Hartman --- drivers/pci/rebar.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/pci/rebar.c +++ b/drivers/pci/rebar.c @@ -231,6 +231,9 @@ void pci_restore_rebar_state(struct pci_ return; pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl); + if (PCI_POSSIBLE_ERROR(ctrl)) + return; + nbars = FIELD_GET(PCI_REBAR_CTRL_NBAR_MASK, ctrl); for (i = 0; i < nbars; i++, pos += 8) { @@ -238,6 +241,9 @@ void pci_restore_rebar_state(struct pci_ int bar_idx, size; pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl); + if (PCI_POSSIBLE_ERROR(ctrl)) + return; + bar_idx = ctrl & PCI_REBAR_CTRL_BAR_IDX; res = pci_resource_n(pdev, bar_idx); size = pci_rebar_bytes_to_size(resource_size(res));