From nobody Tue Sep 30 21:11:25 2025 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.24]) (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 BF584101C8; Thu, 28 Dec 2023 16:57:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="AlQ3hn6V" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1703782654; x=1735318654; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=LCe+OPVf6ypAOTjFWig95nNeJVsgngMAJh/hD3RJ254=; b=AlQ3hn6VQyZT+Yt+YqQ76HGZTBfE3/Qcf9XZViby66JOy81i7qPJ6L4S Ghe4qMMNl+z+9pV0xAxrLSFNvzu+MjOqah77U2u0cdARDWOu841CX/3DB 4uJPxBDi1b+wfBeYKO5ysY6ToW/CnWg9aoAr1Xvdgh+UgPanBB2KsNXin 7Ceqnr+w+5Plt43Y3AemSaDXiQCkUyQibZrOkkOfREbtul7TitYEtvz3q oWDsi3PMPtzzBr3Gkzcqbk0+WCdjJOb6hwL1OCEd1bfazxqODxFLdEVnZ HWuuhytGXPvNNCXq1uC2dIWmrHefTYFIzGfzf30eA+cl6ljSnNMNiFjlo Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10937"; a="399349946" X-IronPort-AV: E=Sophos;i="6.04,312,1695711600"; d="scan'208";a="399349946" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Dec 2023 08:57:34 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10937"; a="728356748" X-IronPort-AV: E=Sophos;i="6.04,312,1695711600"; d="scan'208";a="728356748" Received: from ijarvine-desk1.ger.corp.intel.com (HELO localhost) ([10.94.250.171]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Dec 2023 08:57:28 -0800 From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= To: linux-pci@vger.kernel.org, Bjorn Helgaas , Lorenzo Pieralisi , Rob Herring , =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= , Igor Mammedov , Lukas Wunner , Mika Westerberg , Andy Shevchenko , "Rafael J . Wysocki" , Jesse Barnes , Yinghai Lu , linux-kernel@vger.kernel.org Cc: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= Subject: [PATCH v2 1/7] PCI: Fix resource double counting on remove & rescan Date: Thu, 28 Dec 2023 18:57:01 +0200 Message-Id: <20231228165707.3447-2-ilpo.jarvinen@linux.intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20231228165707.3447-1-ilpo.jarvinen@linux.intel.com> References: <20231228165707.3447-1-ilpo.jarvinen@linux.intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable 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 iomem1: 20000000000-200001fffff : PCI Bus 0000:03 iomem2: 20000000000-200002fffff : PCI Bus 0000:03 iomem3: 20000000000-200003fffff : PCI Bus 0000:03 iomem4: 20000000000-200004fffff : PCI Bus 0000:03 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 iomem1: 20000000000-200000fffff : PCI Bus 0000:03 iomem2: 20000000000-200000fffff : PCI Bus 0000:03 Fixes: a4ac9fea016f ("PCI : Calculate right add_size") Signed-off-by: Ilpo J=C3=A4rvinen --- 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 fd74f1c99dba..e3e6ff8854a7 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -820,11 +820,9 @@ static resource_size_t calculate_memsize(resource_size= _t size, size =3D min_size; if (old_size =3D=3D 1) old_size =3D 0; - if (size < old_size) - size =3D old_size; =20 - size =3D ALIGN(max(size, add_size) + children_add_size, align); - return size; + size =3D max(size, add_size) + children_add_size; + return ALIGN(max(size, old_size), align); } =20 resource_size_t __weak pcibios_window_alignment(struct pci_bus *bus, --=20 2.30.2