| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20250728-luo-pci-v1-5-955b078dd653@kernel.org>
Date: Mon, 28 Jul 2025 01:24:35 -0700
From: Chris Li <chrisl@...nel.org>
To: Bjorn Helgaas <bhelgaas@...gle.com>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
"Rafael J. Wysocki" <rafael@...nel.org>, Danilo Krummrich <dakr@...nel.org>,
Len Brown <lenb@...nel.org>
Cc: linux-kernel@...r.kernel.org, linux-pci@...r.kernel.org,
linux-acpi@...r.kernel.org, David Matlack <dmatlack@...gle.com>,
Pasha Tatashin <tatashin@...gle.com>, Jason Miu <jasonmiu@...gle.com>,
Vipin Sharma <vipinsh@...gle.com>, Saeed Mahameed <saeedm@...dia.com>,
Adithya Jayachandran <ajayachandra@...dia.com>,
Parav Pandit <parav@...dia.com>, William Tu <witu@...dia.com>,
Mike Rapoport <rppt@...nel.org>, Chris Li <chrisl@...nel.org>,
Jason Gunthorpe <jgg@...pe.ca>, Leon Romanovsky <leon@...nel.org>
Subject: [PATCH RFC 05/25] PCI/LUO: Restore state at PCI enumeration
Add a PCI device saved state member to indicate the device is requested
vs depended.
Restore the PCI subsystem saved state folio during PCI enumeration.
When a new PCI device is created, restore the per device state pointer
into the dev->lu.dev_state if the device is found in the saved
devices array, by matching the device path.
Also restore the dev->lu.requested or dev->lu.depended base on the saved
"requested" field. Add such devices to the "probed_devices" list.
Signed-off-by: Chris Li <chrisl@...nel.org>
---
drivers/pci/liveupdate.c | 54 ++++++++++++++++++++++++++++++++++++++++++
drivers/pci/pci.h | 6 +++++
drivers/pci/probe.c | 2 ++
include/linux/dev_liveupdate.h | 2 ++
4 files changed, 64 insertions(+)
diff --git a/drivers/pci/liveupdate.c b/drivers/pci/liveupdate.c
index bbff9b314f99185dfe8941b711cdf0db16b1ed8a..4d13071f5edd6520adb64003262f08d1f79e26c4 100644
--- a/drivers/pci/liveupdate.c
+++ b/drivers/pci/liveupdate.c
@@ -16,6 +16,7 @@
#define PCI_SUBSYSTEM_NAME "pci"
static LIST_HEAD(preserved_devices);
+static LIST_HEAD(probe_devices);
struct pci_dev_ser {
u32 path; /* domain + bus + slot + fn */
@@ -91,6 +92,7 @@ static int build_liveupdate_devices(struct list_head *head)
static void dev_cleanup_liveupdate(struct device *dev)
{
dev->lu.depended = 0;
+ dev->lu.dev_state = NULL;
list_del_init(&dev->lu.lu_next);
}
@@ -310,6 +312,58 @@ struct liveupdate_subsystem pci_liveupdate_ops = {
.name = PCI_SUBSYSTEM_NAME,
};
+static struct pci_ser *pci_state_get(void)
+{
+ static struct pci_ser *pci_state;
+ struct folio *folio;
+ phys_addr_t data = 0;
+ int ret;
+
+ if (pci_state)
+ return pci_state;
+
+ ret = liveupdate_get_subsystem_data(&pci_liveupdate_ops, &data);
+ if (ret || !data)
+ panic("PCI liveupdate: get subsystem data: [%llx] ret: %d", data, ret);
+
+ folio = kho_restore_folio(data);
+ if (!folio)
+ panic("PCI liveupdate: restore folio from %llx failed", data);
+
+ /* Cache the value for future callers. */
+ pci_state = folio_address(folio);
+ return pci_state;
+}
+
+static void pci_dev_do_restore(struct pci_dev *dev, struct pci_dev_ser *s)
+{
+ dev->dev.lu.dev_state = s;
+ if (s->requested)
+ dev->dev.lu.requested = 1;
+ else
+ dev->dev.lu.depended = 1;
+ pci_info(dev, "liveupdate restore [%s] data: [%llx]\n",
+ s->requested ? "requested" : "depended",
+ s->driver_data);
+ list_move_tail(&dev->dev.lu.lu_next, &probe_devices);
+}
+
+void pci_liveupdate_restore(struct pci_dev *dev)
+{
+ int path;
+ struct pci_dev_ser *s, *end;
+
+ if (!liveupdate_state_updated())
+ return;
+
+ path = pci_get_device_path(dev);
+ s = pci_state_get()->devs;
+ end = s + pci_state_get()->count;
+ for (; s < end; s++)
+ if (s->path == path)
+ return pci_dev_do_restore(dev, s);
+}
+
static int __init pci_liveupdate_init(void)
{
int ret;
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 12215ee72afb682b669c0e3a582b5379828e70c4..c9a7383753949994e031dc362920286a475fe2ab 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -1159,4 +1159,10 @@ static inline int pci_msix_write_tph_tag(struct pci_dev *pdev, unsigned int inde
(PCI_CONF1_ADDRESS(bus, dev, func, reg) | \
PCI_CONF1_EXT_REG(reg))
+#ifdef CONFIG_LIVEUPDATE
+void pci_liveupdate_restore(struct pci_dev *dev);
+#else
+static inline void pci_liveupdate_restore(struct pci_dev *dev) {}
+#endif
+
#endif /* DRIVERS_PCI_H */
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index dddd7ebc03d1a6e6ee456e0bf02ab9833a819509..a0605af1a699cd07b09897172803dcba1d2da9f9 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -2017,6 +2017,8 @@ int pci_setup_device(struct pci_dev *dev)
if (pci_early_dump)
early_dump_pci_device(dev);
+ pci_liveupdate_restore(dev);
+
/* Need to have dev->class ready */
dev->cfg_size = pci_cfg_space_size(dev);
diff --git a/include/linux/dev_liveupdate.h b/include/linux/dev_liveupdate.h
index fa664976f9f5e90b8a5a17cfbed8bd2fdc87b7a1..dc65e2b2d92c02bf15440b6745c62cd748721eef 100644
--- a/include/linux/dev_liveupdate.h
+++ b/include/linux/dev_liveupdate.h
@@ -19,6 +19,7 @@ struct device;
* @lu_next: List head for linking the device into live update
* related lists (e.g., a list of devices participating
* in a live update sequence).
+ * @dev_state: Set to the device state at restore.
* @requested: Set if a live update has been requested for this
* device (i.e. device will participate in live update).
* @depended: Set if the device participtate the live update due to
@@ -32,6 +33,7 @@ struct device;
*/
struct dev_liveupdate {
struct list_head lu_next;
+ void *dev_state;
bool requested:1;
bool depended:1;
bool visited:1;
--
2.50.1.487.gc89ff58d15-goog
Powered by blists - more mailing lists