linux-pci.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Sergey Miroshnichenko <s.miroshnichenko@yadro.com>
To: <linux-pci@vger.kernel.org>, <linuxppc-dev@lists.ozlabs.org>
Cc: Bjorn Helgaas <helgaas@kernel.org>, <linux@yadro.com>,
	Sergey Miroshnichenko <s.miroshnichenko@yadro.com>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: [PATCH v6 30/30] Revert "powerpc/powernv/pci: Work around races in PCI bridge enabling"
Date: Thu, 24 Oct 2019 20:12:28 +0300	[thread overview]
Message-ID: <20191024171228.877974-31-s.miroshnichenko@yadro.com> (raw)
In-Reply-To: <20191024171228.877974-1-s.miroshnichenko@yadro.com>

This reverts commit db2173198b9513f7add8009f225afa1f1c79bcc6.

The root cause of this bug is fixed by the following two commits:

  1. "PCI: Fix race condition in pci_enable/disable_device()"
  2. "PCI: Enable bridge's I/O and MEM access for hotplugged devices"

The x86 is also affected by this bug if a PCIe bridge has been hotplugged
without pre-enabling by the BIOS.

CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Sergey Miroshnichenko <s.miroshnichenko@yadro.com>
---
 arch/powerpc/platforms/powernv/pci-ioda.c | 37 -----------------------
 1 file changed, 37 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 33d5ed8c258f..f12f3a49d3bb 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -3119,49 +3119,12 @@ static void pnv_pci_ioda_create_dbgfs(void)
 #endif /* CONFIG_DEBUG_FS */
 }
 
-static void pnv_pci_enable_bridge(struct pci_bus *bus)
-{
-	struct pci_dev *dev = bus->self;
-	struct pci_bus *child;
-
-	/* Empty bus ? bail */
-	if (list_empty(&bus->devices))
-		return;
-
-	/*
-	 * If there's a bridge associated with that bus enable it. This works
-	 * around races in the generic code if the enabling is done during
-	 * parallel probing. This can be removed once those races have been
-	 * fixed.
-	 */
-	if (dev) {
-		int rc = pci_enable_device(dev);
-		if (rc)
-			pci_err(dev, "Error enabling bridge (%d)\n", rc);
-		pci_set_master(dev);
-	}
-
-	/* Perform the same to child busses */
-	list_for_each_entry(child, &bus->children, node)
-		pnv_pci_enable_bridge(child);
-}
-
-static void pnv_pci_enable_bridges(void)
-{
-	struct pci_controller *hose;
-
-	list_for_each_entry(hose, &hose_list, list_node)
-		pnv_pci_enable_bridge(hose->bus);
-}
-
 static void pnv_pci_ioda_fixup(void)
 {
 	pnv_pci_ioda_setup_PEs();
 	pnv_pci_ioda_setup_iommu_api();
 	pnv_pci_ioda_create_dbgfs();
 
-	pnv_pci_enable_bridges();
-
 #ifdef CONFIG_EEH
 	pnv_eeh_post_init();
 #endif
-- 
2.23.0


      parent reply	other threads:[~2019-10-24 17:13 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-24 17:11 [PATCH v6 00/30] PCI: Allow BAR movement during hotplug Sergey Miroshnichenko
2019-10-24 17:11 ` [PATCH v6 01/30] PCI: Fix race condition in pci_enable/disable_device() Sergey Miroshnichenko
2019-10-25 14:33   ` Oxford Semiconductor Ltd OX16PCI954 - weird dmesg Carlo Pisani
2019-10-25 16:37     ` Bjorn Helgaas
2019-10-24 17:12 ` [PATCH v6 02/30] PCI: Enable bridge's I/O and MEM access for hotplugged devices Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 03/30] PCI: hotplug: Add a flag for the movable BARs feature Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 04/30] PCI: Define PCI-specific version of the release_child_resources() Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 05/30] PCI: hotplug: movable BARs: Fix reassigning the released bridge windows Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 06/30] PCI: hotplug: movable BARs: Recalculate all bridge windows during rescan Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 07/30] PCI: hotplug: movable BARs: Don't disable the released bridge windows Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 08/30] PCI: hotplug: movable BARs: Don't allow added devices to steal resources Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 09/30] PCI: Include fixed and immovable BARs into the bus size calculating Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 10/30] PCI: Prohibit assigning BARs and bridge windows to non-direct parents Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 11/30] PCI: hotplug: movable BARs: Try to assign unassigned resources only once Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 12/30] PCI: hotplug: movable BARs: Calculate immovable parts of bridge windows Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 13/30] PCI: hotplug: movable BARs: Compute limits for relocated " Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 14/30] PCI: Make sure bridge windows include their fixed BARs Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 15/30] PCI: Fix assigning the fixed prefetchable resources Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 16/30] PCI: hotplug: movable BARs: Assign fixed and immovable BARs before others Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 17/30] PCI: hotplug: movable BARs: Don't reserve IO/mem bus space Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 18/30] PCI: hotplug: Configure MPS for hot-added bridges during bus rescan Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 19/30] PCI: hotplug: movable BARs: Ignore the MEM BAR offsets from bootloader Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 20/30] powerpc/pci: Fix crash with enabled movable BARs Sergey Miroshnichenko
2019-10-25  1:22   ` Alexey Kardashevskiy
2019-10-24 17:12 ` [PATCH v6 21/30] powerpc/pci: Access PCI config space directly w/o pci_dn Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 22/30] powerpc/pci: Create pci_dn on demand Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 23/30] powerpc/pci: hotplug: Add support for movable BARs Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 24/30] powerpc/powernv/pci: Suppress an EEH error when reading an empty slot Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 25/30] PNP: Don't reserve BARs for PCI when enabled movable BARs Sergey Miroshnichenko
2019-10-27 17:40   ` kbuild test robot
2019-10-24 17:12 ` [PATCH v6 26/30] PCI: hotplug: movable BARs: Enable the feature by default Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 27/30] nvme-pci: Handle movable BARs Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 28/30] PCI/portdrv: Declare support of " Sergey Miroshnichenko
2019-10-24 17:12 ` [PATCH v6 29/30] PCI: pciehp: movable BARs: Trigger a domain rescan on hp events Sergey Miroshnichenko
2019-10-24 17:12 ` Sergey Miroshnichenko [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20191024171228.877974-31-s.miroshnichenko@yadro.com \
    --to=s.miroshnichenko@yadro.com \
    --cc=benh@kernel.crashing.org \
    --cc=helgaas@kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=linux@yadro.com \
    --cc=linuxppc-dev@lists.ozlabs.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).