From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Bjorn Helgaas <bhelgaas@google.com>
Cc: Yinghai Lu <yinghai@kernel.org>,
"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
Gu Zheng <guz.fnst@cn.fujitsu.com>,
Guo Chao <yan@linux.vnet.ibm.com>,
"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Mika Westerberg <mika.westerberg@linux.intel.com>,
Myron Stowe <myron.stowe@gmail.com>,
Benjamin Herrenschmidt <benh@au1.ibm.com>,
linux-scsi@vger.kernel.org, Matthew Garrett <mjg59@srcf.ucam.org>,
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: [PATCH 5/9] PCI / hotplug: Use global PCI rescan-remove locking
Date: Fri, 10 Jan 2014 15:26:12 +0100 [thread overview]
Message-ID: <1423879.kOD1JObQxJ@vostro.rjw.lan> (raw)
In-Reply-To: <20440867.YaQfKrcfsQ@vostro.rjw.lan>
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Multiple race conditions are possible between PCI hotplug and the
generic PCI bus rescan and device removal that can be triggered via
sysfs.
To avoid those race conditions make PCI hotplug use global PCI
rescan-remove locking.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/pci/hotplug/cpci_hotplug_pci.c | 14 ++++++++++++--
drivers/pci/hotplug/cpqphp_pci.c | 8 +++++++-
drivers/pci/hotplug/ibmphp_core.c | 13 +++++++++++--
drivers/pci/hotplug/pciehp_pci.c | 17 +++++++++++++----
drivers/pci/hotplug/rpadlpar_core.c | 19 ++++++++++++++-----
drivers/pci/hotplug/rpaphp_core.c | 4 ++++
drivers/pci/hotplug/s390_pci_hpc.c | 4 +++-
drivers/pci/hotplug/sgi_hotplug.c | 5 +++++
drivers/pci/hotplug/shpchp_pci.c | 18 ++++++++++++++----
9 files changed, 83 insertions(+), 19 deletions(-)
Index: linux-pm/drivers/pci/hotplug/rpadlpar_core.c
===================================================================
--- linux-pm.orig/drivers/pci/hotplug/rpadlpar_core.c
+++ linux-pm/drivers/pci/hotplug/rpadlpar_core.c
@@ -354,10 +354,15 @@ int dlpar_remove_pci_slot(char *drc_name
{
struct pci_bus *bus;
struct slot *slot;
+ int ret = 0;
+
+ pci_lock_rescan_remove();
bus = pcibios_find_pci_bus(dn);
- if (!bus)
- return -EINVAL;
+ if (!bus) {
+ ret = -EINVAL;
+ goto out;
+ }
pr_debug("PCI: Removing PCI slot below EADS bridge %s\n",
bus->self ? pci_name(bus->self) : "<!PHB!>");
@@ -371,7 +376,8 @@ int dlpar_remove_pci_slot(char *drc_name
printk(KERN_ERR
"%s: unable to remove hotplug slot %s\n",
__func__, drc_name);
- return -EIO;
+ ret = -EIO;
+ goto out;
}
}
@@ -382,7 +388,8 @@ int dlpar_remove_pci_slot(char *drc_name
if (pcibios_unmap_io_space(bus)) {
printk(KERN_ERR "%s: failed to unmap bus range\n",
__func__);
- return -ERANGE;
+ ret = -ERANGE;
+ goto out;
}
/* Remove the EADS bridge device itself */
@@ -390,7 +397,9 @@ int dlpar_remove_pci_slot(char *drc_name
pr_debug("PCI: Now removing bridge device %s\n", pci_name(bus->self));
pci_stop_and_remove_bus_device(bus->self);
- return 0;
+ out:
+ pci_unlock_rescan_remove();
+ return ret;
}
/**
Index: linux-pm/drivers/pci/hotplug/cpci_hotplug_pci.c
===================================================================
--- linux-pm.orig/drivers/pci/hotplug/cpci_hotplug_pci.c
+++ linux-pm/drivers/pci/hotplug/cpci_hotplug_pci.c
@@ -254,9 +254,12 @@ int __ref cpci_configure_slot(struct slo
{
struct pci_dev *dev;
struct pci_bus *parent;
+ int ret = 0;
dbg("%s - enter", __func__);
+ pci_lock_rescan_remove();
+
if (slot->dev == NULL) {
dbg("pci_dev null, finding %02x:%02x:%x",
slot->bus->number, PCI_SLOT(slot->devfn), PCI_FUNC(slot->devfn));
@@ -277,7 +280,8 @@ int __ref cpci_configure_slot(struct slo
slot->dev = pci_get_slot(slot->bus, slot->devfn);
if (slot->dev == NULL) {
err("Could not find PCI device for slot %02x", slot->number);
- return -ENODEV;
+ ret = -ENODEV;
+ goto out;
}
}
parent = slot->dev->bus;
@@ -294,8 +298,10 @@ int __ref cpci_configure_slot(struct slo
pci_bus_add_devices(parent);
+ out:
+ pci_unlock_rescan_remove();
dbg("%s - exit", __func__);
- return 0;
+ return ret;
}
int cpci_unconfigure_slot(struct slot* slot)
@@ -308,6 +314,8 @@ int cpci_unconfigure_slot(struct slot* s
return -ENODEV;
}
+ pci_lock_rescan_remove();
+
list_for_each_entry_safe(dev, temp, &slot->bus->devices, bus_list) {
if (PCI_SLOT(dev->devfn) != PCI_SLOT(slot->devfn))
continue;
@@ -318,6 +326,8 @@ int cpci_unconfigure_slot(struct slot* s
pci_dev_put(slot->dev);
slot->dev = NULL;
+ pci_unlock_rescan_remove();
+
dbg("%s - exit", __func__);
return 0;
}
Index: linux-pm/drivers/pci/hotplug/pciehp_pci.c
===================================================================
--- linux-pm.orig/drivers/pci/hotplug/pciehp_pci.c
+++ linux-pm/drivers/pci/hotplug/pciehp_pci.c
@@ -39,22 +39,26 @@ int pciehp_configure_device(struct slot
struct pci_dev *dev;
struct pci_dev *bridge = p_slot->ctrl->pcie->port;
struct pci_bus *parent = bridge->subordinate;
- int num;
+ int num, ret = 0;
struct controller *ctrl = p_slot->ctrl;
+ pci_lock_rescan_remove();
+
dev = pci_get_slot(parent, PCI_DEVFN(0, 0));
if (dev) {
ctrl_err(ctrl, "Device %s already exists "
"at %04x:%02x:00, cannot hot-add\n", pci_name(dev),
pci_domain_nr(parent), parent->number);
pci_dev_put(dev);
- return -EINVAL;
+ ret = -EINVAL;
+ goto out;
}
num = pci_scan_slot(parent, PCI_DEVFN(0, 0));
if (num == 0) {
ctrl_err(ctrl, "No new device found\n");
- return -ENODEV;
+ ret = -ENODEV;
+ goto out;
}
list_for_each_entry(dev, &parent->devices, bus_list)
@@ -73,7 +77,9 @@ int pciehp_configure_device(struct slot
pci_bus_add_devices(parent);
- return 0;
+ out:
+ pci_unlock_rescan_remove();
+ return ret;
}
int pciehp_unconfigure_device(struct slot *p_slot)
@@ -92,6 +98,8 @@ int pciehp_unconfigure_device(struct slo
if (ret)
presence = 0;
+ pci_lock_rescan_remove();
+
/*
* Stopping an SR-IOV PF device removes all the associated VFs,
* which will update the bus->devices list and confuse the
@@ -126,5 +134,6 @@ int pciehp_unconfigure_device(struct slo
pci_dev_put(dev);
}
+ pci_unlock_rescan_remove();
return rc;
}
Index: linux-pm/drivers/pci/hotplug/cpqphp_pci.c
===================================================================
--- linux-pm.orig/drivers/pci/hotplug/cpqphp_pci.c
+++ linux-pm/drivers/pci/hotplug/cpqphp_pci.c
@@ -86,6 +86,8 @@ int cpqhp_configure_device (struct contr
struct pci_bus *child;
int num;
+ pci_lock_rescan_remove();
+
if (func->pci_dev == NULL)
func->pci_dev = pci_get_bus_and_slot(func->bus,PCI_DEVFN(func->device, func->function));
@@ -100,7 +102,7 @@ int cpqhp_configure_device (struct contr
func->pci_dev = pci_get_bus_and_slot(func->bus, PCI_DEVFN(func->device, func->function));
if (func->pci_dev == NULL) {
dbg("ERROR: pci_dev still null\n");
- return 0;
+ goto out;
}
}
@@ -113,6 +115,8 @@ int cpqhp_configure_device (struct contr
pci_dev_put(func->pci_dev);
+ out:
+ pci_unlock_rescan_remove();
return 0;
}
@@ -123,6 +127,7 @@ int cpqhp_unconfigure_device(struct pci_
dbg("%s: bus/dev/func = %x/%x/%x\n", __func__, func->bus, func->device, func->function);
+ pci_lock_rescan_remove();
for (j=0; j<8 ; j++) {
struct pci_dev* temp = pci_get_bus_and_slot(func->bus, PCI_DEVFN(func->device, j));
if (temp) {
@@ -130,6 +135,7 @@ int cpqhp_unconfigure_device(struct pci_
pci_stop_and_remove_bus_device(temp);
}
}
+ pci_unlock_rescan_remove();
return 0;
}
Index: linux-pm/drivers/pci/hotplug/ibmphp_core.c
===================================================================
--- linux-pm.orig/drivers/pci/hotplug/ibmphp_core.c
+++ linux-pm/drivers/pci/hotplug/ibmphp_core.c
@@ -718,6 +718,8 @@ static void ibm_unconfigure_device(struc
func->device, func->function);
debug("func->device << 3 | 0x0 = %x\n", func->device << 3 | 0x0);
+ pci_lock_rescan_remove();
+
for (j = 0; j < 0x08; j++) {
temp = pci_get_bus_and_slot(func->busno, (func->device << 3) | j);
if (temp) {
@@ -725,7 +727,10 @@ static void ibm_unconfigure_device(struc
pci_dev_put(temp);
}
}
+
pci_dev_put(func->dev);
+
+ pci_unlock_rescan_remove();
}
/*
@@ -780,6 +785,8 @@ static int ibm_configure_device(struct p
int flag = 0; /* this is to make sure we don't double scan the bus,
for bridged devices primarily */
+ pci_lock_rescan_remove();
+
if (!(bus_structure_fixup(func->busno)))
flag = 1;
if (func->dev == NULL)
@@ -789,7 +796,7 @@ static int ibm_configure_device(struct p
if (func->dev == NULL) {
struct pci_bus *bus = pci_find_bus(0, func->busno);
if (!bus)
- return 0;
+ goto out;
num = pci_scan_slot(bus,
PCI_DEVFN(func->device, func->function));
@@ -800,7 +807,7 @@ static int ibm_configure_device(struct p
PCI_DEVFN(func->device, func->function));
if (func->dev == NULL) {
err("ERROR... : pci_dev still NULL\n");
- return 0;
+ goto out;
}
}
if (!(flag) && (func->dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)) {
@@ -810,6 +817,8 @@ static int ibm_configure_device(struct p
pci_bus_add_devices(child);
}
+ out:
+ pci_unlock_rescan_remove();
return 0;
}
Index: linux-pm/drivers/pci/hotplug/s390_pci_hpc.c
===================================================================
--- linux-pm.orig/drivers/pci/hotplug/s390_pci_hpc.c
+++ linux-pm/drivers/pci/hotplug/s390_pci_hpc.c
@@ -80,7 +80,9 @@ static int enable_slot(struct hotplug_sl
goto out_deconfigure;
pci_scan_slot(slot->zdev->bus, ZPCI_DEVFN);
+ pci_lock_rescan_remove();
pci_bus_add_devices(slot->zdev->bus);
+ pci_unlock_rescan_remove();
return rc;
@@ -98,7 +100,7 @@ static int disable_slot(struct hotplug_s
return -EIO;
if (slot->zdev->pdev)
- pci_stop_and_remove_bus_device(slot->zdev->pdev);
+ pci_stop_and_remove_bus_device_locked(slot->zdev->pdev);
rc = zpci_disable_device(slot->zdev);
if (rc)
Index: linux-pm/drivers/pci/hotplug/shpchp_pci.c
===================================================================
--- linux-pm.orig/drivers/pci/hotplug/shpchp_pci.c
+++ linux-pm/drivers/pci/hotplug/shpchp_pci.c
@@ -40,7 +40,9 @@ int __ref shpchp_configure_device(struct
struct controller *ctrl = p_slot->ctrl;
struct pci_dev *bridge = ctrl->pci_dev;
struct pci_bus *parent = bridge->subordinate;
- int num;
+ int num, ret = 0;
+
+ pci_lock_rescan_remove();
dev = pci_get_slot(parent, PCI_DEVFN(p_slot->device, 0));
if (dev) {
@@ -48,13 +50,15 @@ int __ref shpchp_configure_device(struct
"at %04x:%02x:%02x, cannot hot-add\n", pci_name(dev),
pci_domain_nr(parent), p_slot->bus, p_slot->device);
pci_dev_put(dev);
- return -EINVAL;
+ ret = -EINVAL;
+ goto out;
}
num = pci_scan_slot(parent, PCI_DEVFN(p_slot->device, 0));
if (num == 0) {
ctrl_err(ctrl, "No new device found\n");
- return -ENODEV;
+ ret = -ENODEV;
+ goto out;
}
list_for_each_entry(dev, &parent->devices, bus_list) {
@@ -75,7 +79,9 @@ int __ref shpchp_configure_device(struct
pci_bus_add_devices(parent);
- return 0;
+ out:
+ pci_unlock_rescan_remove();
+ return ret;
}
int shpchp_unconfigure_device(struct slot *p_slot)
@@ -89,6 +95,8 @@ int shpchp_unconfigure_device(struct slo
ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:%02x\n",
__func__, pci_domain_nr(parent), p_slot->bus, p_slot->device);
+ pci_lock_rescan_remove();
+
list_for_each_entry_safe(dev, temp, &parent->devices, bus_list) {
if (PCI_SLOT(dev->devfn) != p_slot->device)
continue;
@@ -108,6 +116,8 @@ int shpchp_unconfigure_device(struct slo
pci_stop_and_remove_bus_device(dev);
pci_dev_put(dev);
}
+
+ pci_unlock_rescan_remove();
return rc;
}
Index: linux-pm/drivers/pci/hotplug/sgi_hotplug.c
===================================================================
--- linux-pm.orig/drivers/pci/hotplug/sgi_hotplug.c
+++ linux-pm/drivers/pci/hotplug/sgi_hotplug.c
@@ -459,12 +459,15 @@ static int enable_slot(struct hotplug_sl
acpi_scan_lock_release();
}
+ pci_lock_rescan_remove();
+
/* Call the driver for the new device */
pci_bus_add_devices(slot->pci_bus);
/* Call the drivers for the new devices subordinate to PPB */
if (new_ppb)
pci_bus_add_devices(new_bus);
+ pci_unlock_rescan_remove();
mutex_unlock(&sn_hotplug_mutex);
if (rc == 0)
@@ -540,6 +543,7 @@ static int disable_slot(struct hotplug_s
acpi_scan_lock_release();
}
+ pci_lock_rescan_remove();
/* Free the SN resources assigned to the Linux device.*/
list_for_each_entry_safe(dev, temp, &slot->pci_bus->devices, bus_list) {
if (PCI_SLOT(dev->devfn) != slot->device_num + 1)
@@ -550,6 +554,7 @@ static int disable_slot(struct hotplug_s
pci_stop_and_remove_bus_device(dev);
pci_dev_put(dev);
}
+ pci_unlock_rescan_remove();
/* Remove the SSDT for the slot from the ACPI namespace */
if (SN_ACPI_BASE_SUPPORT() && ssdt_id) {
Index: linux-pm/drivers/pci/hotplug/rpaphp_core.c
===================================================================
--- linux-pm.orig/drivers/pci/hotplug/rpaphp_core.c
+++ linux-pm/drivers/pci/hotplug/rpaphp_core.c
@@ -398,7 +398,9 @@ static int enable_slot(struct hotplug_sl
return retval;
if (state == PRESENT) {
+ pci_lock_rescan_remove();
pcibios_add_pci_devices(slot->bus);
+ pci_unlock_rescan_remove();
slot->state = CONFIGURED;
} else if (state == EMPTY) {
slot->state = EMPTY;
@@ -418,7 +420,9 @@ static int disable_slot(struct hotplug_s
if (slot->state == NOT_CONFIGURED)
return -EINVAL;
+ pci_lock_rescan_remove();
pcibios_remove_pci_devices(slot->bus);
+ pci_unlock_rescan_remove();
vm_unmap_aliases();
slot->state = NOT_CONFIGURED;
next prev parent reply other threads:[~2014-01-10 14:18 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-26 1:28 [PATCH v2 00/10] PCI: Double removing fix and allocate 64bit mmio pref Yinghai Lu
2013-11-26 1:28 ` [PATCH v2 01/10] PCI: Use device_release_driver in pci_stop_root_bus Yinghai Lu
2013-11-27 1:09 ` Rafael J. Wysocki
2013-11-26 1:28 ` [PATCH v2 02/10] PCI: Move back pci_proc_attach_devices calling Yinghai Lu
2013-11-26 1:28 ` [PATCH v2 03/10] PCI: Move resources and bus_list releasing to pci_release_dev Yinghai Lu
2013-11-27 1:15 ` Rafael J. Wysocki
2013-11-27 2:15 ` Yinghai Lu
2013-11-26 1:28 ` [PATCH v2 04/10] PCI: Destroy pci dev only once Yinghai Lu
2013-11-26 3:38 ` Bjorn Helgaas
2013-11-26 19:34 ` Yinghai Lu
2013-11-26 20:13 ` Yinghai Lu
2013-11-27 1:24 ` Rafael J. Wysocki
2013-11-27 2:26 ` Yinghai Lu
2013-11-29 23:38 ` Rafael J. Wysocki
2013-11-29 23:45 ` Rafael J. Wysocki
2013-11-30 0:31 ` Rafael J. Wysocki
2013-11-30 21:37 ` Rafael J. Wysocki
2013-11-30 22:27 ` Yinghai Lu
2013-12-01 1:24 ` Rafael J. Wysocki
2013-12-02 1:29 ` Rafael J. Wysocki
2013-12-02 14:49 ` Rafael J. Wysocki
2013-12-05 22:40 ` Bjorn Helgaas
2013-12-06 1:21 ` Rafael J. Wysocki
2013-12-06 6:29 ` Yinghai Lu
2014-01-10 14:20 ` [PATCH 0/9] PCI: Eliminate race conditions between hotplug and sysfs rescan/remove (Was: Re: [PATCH v2 04/10] PCI: Destroy pci dev only once) Rafael J. Wysocki
2014-01-10 14:22 ` [PATCH 1/9] PCI: Global rescan-remove lock Rafael J. Wysocki
2014-01-10 14:23 ` [PATCH 2/9] ACPI / PCI: Use global PCI rescan-remove locking in PCI root hotplug Rafael J. Wysocki
2014-01-10 14:24 ` [PATCH 3/9] ACPI / hotplug / PCI: Use global PCI rescan-remove locking Rafael J. Wysocki
2014-01-10 14:25 ` [PATCH 4/9] PCMCIA / cardbus: " Rafael J. Wysocki
2014-01-10 14:26 ` Rafael J. Wysocki [this message]
2014-01-10 14:27 ` [PATCH 6/9] platform / x86: " Rafael J. Wysocki
2014-01-10 14:27 ` [PATCH 7/9] MPT / PCI: Use pci_stop_and_remove_bus_device_locked() Rafael J. Wysocki
2014-01-10 14:28 ` [PATCH 8/9] powerpc / eeh_driver: Use global PCI rescan-remove locking Rafael J. Wysocki
2014-01-15 13:36 ` [Update][PATCH " Rafael J. Wysocki
2014-01-15 17:38 ` Bjorn Helgaas
2014-01-10 14:29 ` [PATCH 9/9] Xen / PCI: " Rafael J. Wysocki
2014-01-15 18:02 ` [PATCH 0/9] PCI: Eliminate race conditions between hotplug and sysfs rescan/remove (Was: Re: [PATCH v2 04/10] PCI: Destroy pci dev only once) Bjorn Helgaas
2013-12-06 6:52 ` [PATCH v2 04/10] PCI: Destroy pci dev only once Yinghai Lu
2013-12-07 1:27 ` Rafael J. Wysocki
2013-12-08 3:31 ` Yinghai Lu
2013-12-08 3:50 ` Greg Kroah-Hartman
2013-12-09 15:24 ` Ethan Zhao
2013-12-09 19:08 ` Greg Kroah-Hartman
2013-12-10 7:43 ` Ethan Zhao
2014-01-13 1:03 ` [PATCH] PCI / remove: Check parent kobject in pci_destroy_dev() (was: Re: [PATCH v2 04/10] PCI: Destroy pci dev only once) Rafael J. Wysocki
2013-11-27 1:17 ` [PATCH v2 04/10] PCI: Destroy pci dev only once Rafael J. Wysocki
2013-11-26 1:28 ` [PATCH v2 05/10] PCI: pcibus address to resource converting take bus directly Yinghai Lu
2013-11-26 1:28 ` [PATCH v2 06/10] PCI: Add pcibios_bus_addr_to_res() Yinghai Lu
2013-11-26 1:28 ` [PATCH v2 07/10] PCI: Try to allocate mem64 above 4G at first Yinghai Lu
2013-11-26 4:15 ` Bjorn Helgaas
2013-11-26 20:14 ` Yinghai Lu
2013-11-26 1:28 ` [PATCH v2 08/10] PCI: Try best to allocate pref mmio 64bit above 4g Yinghai Lu
2013-11-26 4:17 ` Bjorn Helgaas
2013-11-26 6:59 ` Guo Chao
2013-11-26 17:53 ` Bjorn Helgaas
2013-11-26 22:00 ` Yinghai Lu
2013-11-26 22:01 ` Bjorn Helgaas
2013-11-27 0:33 ` Yinghai Lu
2013-11-26 1:28 ` [PATCH v2 09/10] PCI: Sort pci root bus resources list Yinghai Lu
2013-11-26 4:18 ` Bjorn Helgaas
2013-11-26 1:28 ` [PATCH v2 10/10] intel-gtt: Read 64bit for gmar_bus_addr Yinghai Lu
2013-11-26 3:46 ` Bjorn Helgaas
2013-11-26 19:35 ` Yinghai Lu
2013-12-11 18:48 ` Bjorn Helgaas
2013-12-11 19:58 ` Yinghai Lu
2013-12-21 0:27 ` Bjorn Helgaas
2013-12-21 1:19 ` Yinghai Lu
2013-12-21 18:50 ` Bjorn Helgaas
2013-12-23 22:33 ` Bjorn Helgaas
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