From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 D583419FA9D; Thu, 15 Aug 2024 13:45:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723729510; cv=none; b=WuSPYDF43fC3b+6HP29OEzfttYVTMWRxQ66gUPNv+Ubs78O/HA21JGqVj1/pSc3YRVsswghRiciibjXJjkWdvbVvlpM08liv8YL41HXsCA1JCS+EEVovGhWwd+4dhT3Rak9Fyy0kJ+kQmWk4cy1Q6VWibNtKS/lWip6r4iGpQO0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723729510; c=relaxed/simple; bh=RoVkF2NScyNb0nvtEdgkYIj07aC9c12vHiaXmFqpFbU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=CwFn8ESAtrUzXKYfmjrhyNKUNOkUGEJpfgBRcs5J0ZHJfpT9EhwCdEC1rn+VJNqJ/9k9nZXrSCqQD+aIwlQs87hlD9ASjonxkYkZ51zkOS6FESsZpEqvZL0Naq5kn/ff5krDqUqbcxob6uSM3eQgFblvq1tHZzrE0FCouL4F9uo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=FN6OirEU; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="FN6OirEU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1048FC32786; Thu, 15 Aug 2024 13:45:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1723729510; bh=RoVkF2NScyNb0nvtEdgkYIj07aC9c12vHiaXmFqpFbU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FN6OirEUwk7jH+XjvLaLRXatW+p22q54UOYopJTSzIXtHDWf7ZbUxKBtl/Qvun1+F RPW04rYRU7icr3JS7q7XnHFk3kkSk7zJCmatPgyLovPm0GyWrj9swVIN26oaaBBsFh xapAORHB1CFB/GbhS7HkvUoUaC1mmRTruNXtJKJw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Lidong Wang , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , Bjorn Helgaas , Mika Westerberg , Sasha Levin Subject: [PATCH 5.15 120/484] PCI: Fix resource double counting on remove & rescan Date: Thu, 15 Aug 2024 15:19:38 +0200 Message-ID: <20240815131945.927626233@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240815131941.255804951@linuxfoundation.org> References: <20240815131941.255804951@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ilpo Järvinen [ Upstream commit 903534fa7d30214d8ba840ab1cd9e917e0c88e41 ] pbus_size_mem() keeps the size of the optional resources in children_add_size. When calculating the PCI bridge window size, calculate_memsize() lower bounds size by old_size before adding children_add_size and performing the window size alignment. This results in double counting for the resources in children_add_size because old_size may be based on the previous size of the bridge window after it has already included children_add_size (that is, size1 in pbus_size_mem() from an earlier invocation of that function). As a result, on repeated remove of the bus & rescan cycles the resource size keeps increasing when children_add_size is non-zero as can be seen from this extract: iomem0: 23fffd00000-23fffdfffff : PCI Bus 0000:03 # 1MiB iomem1: 20000000000-200001fffff : PCI Bus 0000:03 # 2MiB iomem2: 20000000000-200002fffff : PCI Bus 0000:03 # 3MiB iomem3: 20000000000-200003fffff : PCI Bus 0000:03 # 4MiB iomem4: 20000000000-200004fffff : PCI Bus 0000:03 # 5MiB Solve the double counting by moving old_size check later in calculate_memsize() so that children_add_size is already accounted for. After the patch, the bridge window retains its size as expected: iomem0: 23fffd00000-23fffdfffff : PCI Bus 0000:03 # 1MiB iomem1: 20000000000-200000fffff : PCI Bus 0000:03 # 1MiB iomem2: 20000000000-200000fffff : PCI Bus 0000:03 # 1MiB Fixes: a4ac9fea016f ("PCI : Calculate right add_size") Link: https://lore.kernel.org/r/20240507102523.57320-2-ilpo.jarvinen@linux.intel.com Tested-by: Lidong Wang Signed-off-by: Ilpo Järvinen Signed-off-by: Bjorn Helgaas Reviewed-by: Mika Westerberg Signed-off-by: Sasha Levin --- drivers/pci/setup-bus.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 16d291e10627b..a159bfdfa2512 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -824,11 +824,9 @@ static resource_size_t calculate_memsize(resource_size_t size, size = min_size; if (old_size == 1) old_size = 0; - if (size < old_size) - size = old_size; - size = ALIGN(max(size, add_size) + children_add_size, align); - return size; + size = max(size, add_size) + children_add_size; + return ALIGN(max(size, old_size), align); } resource_size_t __weak pcibios_window_alignment(struct pci_bus *bus, -- 2.43.0