| 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: <20240529133446.28446-11-Jonathan.Cameron@huawei.com>
Date: Wed, 29 May 2024 14:34:37 +0100
From: Jonathan Cameron <Jonathan.Cameron@...wei.com>
To: Marc Zyngier <maz@...nel.org>, Will Deacon <will@...nel.org>, Catalin
Marinas <catalin.marinas@....com>, <linux-acpi@...r.kernel.org>,
<linux-arch@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
<linux-arm-kernel@...ts.infradead.org>, <linux-pm@...r.kernel.org>
CC: Mark Rutland <mark.rutland@....com>, Thomas Gleixner <tglx@...utronix.de>,
Peter Zijlstra <peterz@...radead.org>, <loongarch@...ts.linux.dev>,
<x86@...nel.org>, Russell King <linux@...linux.org.uk>, "Rafael J . Wysocki"
<rafael@...nel.org>, Miguel Luis <miguel.luis@...cle.com>, James Morse
<james.morse@....com>, Salil Mehta <salil.mehta@...wei.com>, Jean-Philippe
Brucker <jean-philippe@...aro.org>, Hanjun Guo <guohanjun@...wei.com>, Gavin
Shan <gshan@...hat.com>, Ingo Molnar <mingo@...hat.com>, Borislav Petkov
<bp@...en8.de>, Dave Hansen <dave.hansen@...ux.intel.com>,
<linuxarm@...wei.com>, <justin.he@....com>, <jianyong.wu@....com>
Subject: [PATCH v10 10/19] ACPI: Add post_eject to struct acpi_scan_handler for cpu hotplug
From: James Morse <james.morse@....com>
struct acpi_scan_handler has a detach callback that is used to remove
a driver when a bus is changed. When interacting with an eject-request,
the detach callback is called before _EJ0.
This means the ACPI processor driver can't use _STA to determine if a
CPU has been made not-present, or some of the other _STA bits have been
changed. acpi_processor_remove() needs to know the value of _STA after
_EJ0 has been called.
Add a post_eject callback to struct acpi_scan_handler. This is called
after acpi_scan_hot_remove() has successfully called _EJ0. Because
acpi_scan_check_and_detach() also clears the handler pointer,
it needs to be told if the caller will go on to call
acpi_bus_post_eject(), so that acpi_device_clear_enumerated()
and clearing the handler pointer can be deferred.
An extra flag is added to flags field introduced in the previous
patch to achieve this.
Signed-off-by: James Morse <james.morse@....com>
Reviewed-by: Gavin Shan <gshan@...hat.com>
Tested-by: Miguel Luis <miguel.luis@...cle.com>
Tested-by: Vishnu Pajjuri <vishnu@...amperecomputing.com>
Tested-by: Jianyong Wu <jianyong.wu@....com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
Reviewed-by: Hanjun Guo <guohanjun@...wei.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@...wei.com>
---
drivers/acpi/acpi_processor.c | 4 ++--
drivers/acpi/scan.c | 30 +++++++++++++++++++++++++++---
include/acpi/acpi_bus.h | 1 +
3 files changed, 30 insertions(+), 5 deletions(-)
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index f0b7a789f0a1..64e10bad8072 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -475,7 +475,7 @@ static int acpi_processor_add(struct acpi_device *device,
#ifdef CONFIG_ACPI_HOTPLUG_CPU
/* Removal */
-static void acpi_processor_remove(struct acpi_device *device)
+static void acpi_processor_post_eject(struct acpi_device *device)
{
struct acpi_processor *pr;
@@ -643,7 +643,7 @@ static struct acpi_scan_handler processor_handler = {
.ids = processor_device_ids,
.attach = acpi_processor_add,
#ifdef CONFIG_ACPI_HOTPLUG_CPU
- .detach = acpi_processor_remove,
+ .post_eject = acpi_processor_post_eject,
#endif
.hotplug = {
.enabled = true,
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 4d649ce5876f..0aa20623525a 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -244,6 +244,7 @@ static int acpi_scan_try_to_offline(struct acpi_device *device)
}
#define ACPI_SCAN_CHECK_FLAG_STATUS BIT(0)
+#define ACPI_SCAN_CHECK_FLAG_EJECT BIT(1)
static int acpi_scan_check_and_detach(struct acpi_device *adev, void *p)
{
@@ -272,8 +273,6 @@ static int acpi_scan_check_and_detach(struct acpi_device *adev, void *p)
if (handler) {
if (handler->detach)
handler->detach(adev);
-
- adev->handler = NULL;
} else {
device_release_driver(&adev->dev);
}
@@ -283,6 +282,28 @@ static int acpi_scan_check_and_detach(struct acpi_device *adev, void *p)
*/
acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
adev->flags.initialized = false;
+
+ /* For eject this is deferred to acpi_bus_post_eject() */
+ if (!(flags & ACPI_SCAN_CHECK_FLAG_EJECT)) {
+ adev->handler = NULL;
+ acpi_device_clear_enumerated(adev);
+ }
+ return 0;
+}
+
+static int acpi_bus_post_eject(struct acpi_device *adev, void *not_used)
+{
+ struct acpi_scan_handler *handler = adev->handler;
+
+ acpi_dev_for_each_child_reverse(adev, acpi_bus_post_eject, NULL);
+
+ if (handler) {
+ if (handler->post_eject)
+ handler->post_eject(adev);
+
+ adev->handler = NULL;
+ }
+
acpi_device_clear_enumerated(adev);
return 0;
@@ -300,6 +321,7 @@ static int acpi_scan_hot_remove(struct acpi_device *device)
acpi_handle handle = device->handle;
unsigned long long sta;
acpi_status status;
+ uintptr_t flags = ACPI_SCAN_CHECK_FLAG_EJECT;
if (device->handler && device->handler->hotplug.demand_offline) {
if (!acpi_scan_is_offline(device, true))
@@ -312,7 +334,7 @@ static int acpi_scan_hot_remove(struct acpi_device *device)
acpi_handle_debug(handle, "Ejecting\n");
- acpi_bus_trim(device);
+ acpi_scan_check_and_detach(device, (void *)flags);
acpi_evaluate_lck(handle, 0);
/*
@@ -335,6 +357,8 @@ static int acpi_scan_hot_remove(struct acpi_device *device)
} else if (sta & ACPI_STA_DEVICE_ENABLED) {
acpi_handle_warn(handle,
"Eject incomplete - status 0x%llx\n", sta);
+ } else {
+ acpi_bus_post_eject(device, NULL);
}
return 0;
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 1a4dfd7a1c4a..05ca49478537 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -134,6 +134,7 @@ struct acpi_scan_handler {
bool (*match)(const char *idstr, const struct acpi_device_id **matchid);
int (*attach)(struct acpi_device *dev, const struct acpi_device_id *id);
void (*detach)(struct acpi_device *dev);
+ void (*post_eject)(struct acpi_device *dev);
void (*bind)(struct device *phys_dev);
void (*unbind)(struct device *phys_dev);
struct acpi_hotplug_profile hotplug;
--
2.39.2
Powered by blists - more mailing lists