From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 40476C433F5 for ; Mon, 13 Sep 2021 23:46:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 12B8E61056 for ; Mon, 13 Sep 2021 23:46:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245237AbhIMXrf (ORCPT ); Mon, 13 Sep 2021 19:47:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:35044 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230396AbhIMXr0 (ORCPT ); Mon, 13 Sep 2021 19:47:26 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8212161056; Mon, 13 Sep 2021 23:46:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631576769; bh=svwTodIvvUH1K7I0QXV/Fq8OZfMGRbpkLLRzATMEnjw=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=XAuVecKo1bG+oD8+ClPB40My9Pj9qGl95fnW8Uj+gFDXnPYwOqohKxNilK8nBa+98 KVBE6T1qbqdNDXPcPvK6FlvVj5xPCRgJHpIcIfhPcmHjXS4hkFgecI++gm43/R34RI JufosPHPUf8XI2EaLBmg5+HOwogRILhzptusK8SXyOPnZaqYnYsq2VF53ltnPVSLfk w9nBbmaRazSYAaiVgJm/3SrqOnfUmS2pYjwUtRpYjG/IrQdXsVcEzUmaa5BtLBlIbH U+fWITzQfzomzb6GREsqhi3Acv7UOEq6o9NjYFxamf+Qhal4pMPu0diA1qRCbg0utW Csv7J0LQd0Dcg== Date: Mon, 13 Sep 2021 18:46:08 -0500 From: Bjorn Helgaas To: Dave Jones , Linus Torvalds , Heiner Kallweit Cc: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org Subject: Re: Linux 5.15-rc1 Message-ID: <20210913234608.GA1381155@bjorn-Precision-5520> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210913141818.GA27911@codemonkey.org.uk> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 13, 2021 at 10:18:18AM -0400, Dave Jones wrote: > On Sun, Sep 12, 2021 at 04:58:27PM -0700, Linus Torvalds wrote: > > So 5.15 isn't shaping up to be a particularly large release, at least > > in number of commits. At only just over 10k non-merge commits, this is > > in fact the smallest rc1 we have had in the 5.x series. We're usually > > hovering in the 12-14k commit range. > > This release takes over two minutes longer to boot on one my > machines than 5.14. The time just seems to be unaccounted for, even > with initcall_debug > ... > [ 2.194093] pci 0000:01:00.0: calling quirk_f0_vpd_link+0x0/0x60 @ 1 > [ 2.194097] pci 0000:01:00.0: quirk_f0_vpd_link+0x0/0x60 took 0 usecs > [ 2.194100] pci 0000:01:00.0: [8086:10fb] type 00 class 0x020000 > [ 2.194109] pci 0000:01:00.0: reg 0x10: [mem 0xd0080000-0xd00fffff 64bit pref] > [ 2.194113] pci 0000:01:00.0: reg 0x18: [io 0xe020-0xe03f] > [ 2.194121] pci 0000:01:00.0: reg 0x20: [mem 0xd0104000-0xd0107fff 64bit pref] > [ 2.194126] pci 0000:01:00.0: reg 0x30: [mem 0xdfd80000-0xdfdfffff pref] > [ 2.194136] pci 0000:01:00.0: calling quirk_igfx_skip_te_disable+0x0/0x50 @ 1 > [ 2.194139] pci 0000:01:00.0: quirk_igfx_skip_te_disable+0x0/0x50 took 0 usecs > [ 2.194164] pci 0000:01:00.0: PME# supported from D0 D3hot D3cold > > * stall here for 86 seconds * > > [ 88.675114] pci 0000:01:00.0: reg 0x184: [mem 0x00000000-0x00003fff 64bit pref] > ... > 7bac54497c3e3b2ca37b7043f1fa78586540f10e is the first bad commit > commit 7bac54497c3e3b2ca37b7043f1fa78586540f10e > Author: Heiner Kallweit > Date: Sun Aug 8 19:22:52 2021 +0200 > > PCI/VPD: Determine VPD size in pci_vpd_init() > > Determine VPD size in pci_vpd_init(). > > Quirks set dev->vpd.len to a non-zero value, so they cause us to skip the > dynamic size calculation. Prerequisite is that we move the quirks from > FINAL to HEADER so they are run before pci_vpd_init(). > > Link: https://lore.kernel.org/r/cc4a6538-557a-294d-4f94-e6d1d3c91589@gmail.com > Signed-off-by: Heiner Kallweit > Signed-off-by: Bjorn Helgaas > > > Which unfortunately doesn't revert cleanly I can't test it reverted in > isolation. > > My guess is there's something quirky about the PCI bus on this machine > that causes stalls until we hit timeout, but I'm not sure where to begin > debugging this. Sorry for the inconvenience of this, and thank you very much for doing the bisection to track it down. We *could* revert 7bac54497c3e, but it'd be messy because a bunch of follow-up stuff depends on it. I propose something like the patch below. Would you mind trying it out? commit 4ede9949b93c ("PCI/VPD: Defer VPD sizing until first access") Author: Bjorn Helgaas Date: Mon Sep 13 16:13:26 2021 -0500 PCI/VPD: Defer VPD sizing until first access 7bac54497c3e ("PCI/VPD: Determine VPD size in pci_vpd_init()") reads VPD at enumeration-time to find the size. But this is quite slow, and we don't need the size until we actually need data from VPD. Dave reported a boot slowdown of more than two minutes [1]. Defer the VPD sizing until a driver or the user requests information from VPD. If devices are quirked because VPD is known not to work, clear the vpd.cap pointer so we don't access it at all. [1] https://lore.kernel.org/r/20210913141818.GA27911@codemonkey.org.uk/ Fixes: 7bac54497c3e ("PCI/VPD: Determine VPD size in pci_vpd_init()") Signed-off-by: Bjorn Helgaas diff --git a/drivers/pci/vpd.c b/drivers/pci/vpd.c index 25557b272a4f..ca823ceee10c 100644 --- a/drivers/pci/vpd.c +++ b/drivers/pci/vpd.c @@ -46,13 +46,12 @@ static struct pci_dev *pci_get_func0_dev(struct pci_dev *dev) } #define PCI_VPD_MAX_SIZE (PCI_VPD_ADDR_MASK + 1) -#define PCI_VPD_SZ_INVALID UINT_MAX /** * pci_vpd_size - determine actual size of Vital Product Data * @dev: pci device struct */ -static size_t pci_vpd_size(struct pci_dev *dev) +static void pci_vpd_size(struct pci_dev *dev) { size_t off = 0, size; unsigned char tag, header[1+2]; /* 1 byte tag, 2 bytes length */ @@ -71,7 +70,7 @@ static size_t pci_vpd_size(struct pci_dev *dev) if (pci_read_vpd(dev, off + 1, 2, &header[1]) != 2) { pci_warn(dev, "failed VPD read at offset %zu\n", off + 1); - return off ?: PCI_VPD_SZ_INVALID; + goto finish; } size = pci_vpd_lrdt_size(header); if (off + size > PCI_VPD_MAX_SIZE) @@ -87,16 +86,19 @@ static size_t pci_vpd_size(struct pci_dev *dev) off += PCI_VPD_SRDT_TAG_SIZE + size; if (tag == PCI_VPD_STIN_END) /* End tag descriptor */ - return off; + goto finish; } } - return off; + goto finish; error: pci_info(dev, "invalid VPD tag %#04x (size %zu) at offset %zu%s\n", header[0], size, off, off == 0 ? "; assume missing optional EEPROM" : ""); - return off ?: PCI_VPD_SZ_INVALID; +finish: + dev->vpd.len = off; + if (off == 0) + dev->vpd.cap = 0; /* No VPD at all */ } /* @@ -145,9 +147,6 @@ static ssize_t pci_vpd_read(struct pci_dev *dev, loff_t pos, size_t count, loff_t end = pos + count; u8 *buf = arg; - if (!vpd->cap) - return -ENODEV; - if (pos < 0) return -EINVAL; @@ -206,9 +205,6 @@ static ssize_t pci_vpd_write(struct pci_dev *dev, loff_t pos, size_t count, loff_t end = pos + count; int ret = 0; - if (!vpd->cap) - return -ENODEV; - if (pos < 0 || (pos & 3) || (count & 3)) return -EINVAL; @@ -244,12 +240,6 @@ void pci_vpd_init(struct pci_dev *dev) { dev->vpd.cap = pci_find_capability(dev, PCI_CAP_ID_VPD); mutex_init(&dev->vpd.lock); - - if (!dev->vpd.len) - dev->vpd.len = pci_vpd_size(dev); - - if (dev->vpd.len == PCI_VPD_SZ_INVALID) - dev->vpd.cap = 0; } static ssize_t vpd_read(struct file *filp, struct kobject *kobj, @@ -294,25 +284,29 @@ const struct attribute_group pci_dev_vpd_attr_group = { void *pci_vpd_alloc(struct pci_dev *dev, unsigned int *size) { - unsigned int len = dev->vpd.len; + struct pci_vpd *vpd = &dev->vpd; + unsigned int len; void *buf; int cnt; - if (!dev->vpd.cap) + if (!vpd->cap) return ERR_PTR(-ENODEV); buf = kmalloc(len, GFP_KERNEL); if (!buf) return ERR_PTR(-ENOMEM); - cnt = pci_read_vpd(dev, 0, len, buf); + if (vpd->len == 0) + pci_vpd_size(dev); + + cnt = pci_read_vpd(dev, 0, vpd->len, buf); if (cnt != len) { kfree(buf); return ERR_PTR(-EIO); } if (size) - *size = len; + *size = vpd->len; return buf; } @@ -374,6 +368,7 @@ static int pci_vpd_find_info_keyword(const u8 *buf, unsigned int off, */ ssize_t pci_read_vpd(struct pci_dev *dev, loff_t pos, size_t count, void *buf) { + struct pci_vpd *vpd; ssize_t ret; if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0) { @@ -381,11 +376,27 @@ ssize_t pci_read_vpd(struct pci_dev *dev, loff_t pos, size_t count, void *buf) if (!dev) return -ENODEV; + vpd = &dev->vpd; + if (!vpd->cap) { + pci_dev_put(dev); + return -ENODEV; + } + + if (vpd->len == 0) + pci_vpd_size(dev); + ret = pci_vpd_read(dev, pos, count, buf); pci_dev_put(dev); return ret; } + vpd = &dev->vpd; + if (!vpd->cap) + return -ENODEV; + + if (vpd->len == 0) + pci_vpd_size(dev); + return pci_vpd_read(dev, pos, count, buf); } EXPORT_SYMBOL(pci_read_vpd); @@ -399,6 +410,7 @@ EXPORT_SYMBOL(pci_read_vpd); */ ssize_t pci_write_vpd(struct pci_dev *dev, loff_t pos, size_t count, const void *buf) { + struct pci_vpd *vpd; ssize_t ret; if (dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0) { @@ -406,11 +418,26 @@ ssize_t pci_write_vpd(struct pci_dev *dev, loff_t pos, size_t count, const void if (!dev) return -ENODEV; + vpd = &dev->vpd; + if (!vpd->cap) { + pci_dev_put(dev); + return -ENODEV; + } + + if (vpd->len == 0) + pci_vpd_size(dev); + ret = pci_vpd_write(dev, pos, count, buf); pci_dev_put(dev); return ret; } + if (!vpd->cap) + return -ENODEV; + + if (vpd->len == 0) + pci_vpd_size(dev); + return pci_vpd_write(dev, pos, count, buf); } EXPORT_SYMBOL(pci_write_vpd); @@ -500,27 +527,27 @@ DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_INTEL, PCI_ANY_ID, */ static void quirk_blacklist_vpd(struct pci_dev *dev) { - dev->vpd.len = PCI_VPD_SZ_INVALID; + dev->vpd.cap = 0; pci_warn(dev, FW_BUG "disabling VPD access (can't determine size of non-standard VPD format)\n"); } -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LSI_LOGIC, 0x0060, quirk_blacklist_vpd); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LSI_LOGIC, 0x007c, quirk_blacklist_vpd); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LSI_LOGIC, 0x0413, quirk_blacklist_vpd); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LSI_LOGIC, 0x0078, quirk_blacklist_vpd); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LSI_LOGIC, 0x0079, quirk_blacklist_vpd); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LSI_LOGIC, 0x0073, quirk_blacklist_vpd); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LSI_LOGIC, 0x0071, quirk_blacklist_vpd); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LSI_LOGIC, 0x005b, quirk_blacklist_vpd); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LSI_LOGIC, 0x002f, quirk_blacklist_vpd); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LSI_LOGIC, 0x005d, quirk_blacklist_vpd); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_LSI_LOGIC, 0x005f, quirk_blacklist_vpd); -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATTANSIC, PCI_ANY_ID, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0060, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x007c, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0413, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0078, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0079, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0073, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0071, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x005b, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x002f, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x005d, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x005f, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATTANSIC, PCI_ANY_ID, quirk_blacklist_vpd); /* * The Amazon Annapurna Labs 0x0031 device id is reused for other non Root Port * device types, so the quirk is registered for the PCI_CLASS_BRIDGE_PCI class. */ -DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_VENDOR_ID_AMAZON_ANNAPURNA_LABS, 0x0031, - PCI_CLASS_BRIDGE_PCI, 8, quirk_blacklist_vpd); +DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_VENDOR_ID_AMAZON_ANNAPURNA_LABS, 0x0031, + PCI_CLASS_BRIDGE_PCI, 8, quirk_blacklist_vpd); static void quirk_chelsio_extend_vpd(struct pci_dev *dev) { @@ -545,7 +572,7 @@ static void quirk_chelsio_extend_vpd(struct pci_dev *dev) dev->vpd.len = 2048; } -DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CHELSIO, PCI_ANY_ID, - quirk_chelsio_extend_vpd); +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_CHELSIO, PCI_ANY_ID, + quirk_chelsio_extend_vpd); #endif