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-rw-r--r--Documentation/admin-guide/kernel-parameters.txt15
-rw-r--r--arch/x86/kernel/acpi/sleep.c4
-rw-r--r--drivers/acpi/sleep.c26
-rw-r--r--include/linux/acpi.h2
-rw-r--r--include/linux/suspend.h1
-rw-r--r--kernel/power/power.h1
-rw-r--r--kernel/power/swap.c16
7 files changed, 53 insertions, 12 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 9725c546a0d4..10e0a3a27516 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -225,14 +225,23 @@
For broken nForce2 BIOS resulting in XT-PIC timer.
acpi_sleep= [HW,ACPI] Sleep options
- Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig,
- old_ordering, nonvs, sci_force_enable, nobl }
+ Format: { s3_bios, s3_mode, s3_beep, s4_hwsig,
+ s4_nohwsig, old_ordering, nonvs,
+ sci_force_enable, nobl }
See Documentation/power/video.rst for information on
s3_bios and s3_mode.
s3_beep is for debugging; it makes the PC's speaker beep
as soon as the kernel's real-mode entry point is called.
+ s4_hwsig causes the kernel to check the ACPI hardware
+ signature during resume from hibernation, and gracefully
+ refuse to resume if it has changed. This complies with
+ the ACPI specification but not with reality, since
+ Windows does not do this and many laptops do change it
+ on docking. So the default behaviour is to allow resume
+ and simply warn when the signature changes, unless the
+ s4_hwsig option is enabled.
s4_nohwsig prevents ACPI hardware signature from being
- used during resume from hibernation.
+ used (or even warned about) during resume.
old_ordering causes the ACPI 1.0 ordering of the _PTS
control method, with respect to putting devices into
low power states, to be enforced (the ACPI 2.0 ordering
diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c
index 3f85fcae450c..1e97f944b47d 100644
--- a/arch/x86/kernel/acpi/sleep.c
+++ b/arch/x86/kernel/acpi/sleep.c
@@ -139,8 +139,10 @@ static int __init acpi_sleep_setup(char *str)
if (strncmp(str, "s3_beep", 7) == 0)
acpi_realmode_flags |= 4;
#ifdef CONFIG_HIBERNATION
+ if (strncmp(str, "s4_hwsig", 8) == 0)
+ acpi_check_s4_hw_signature(1);
if (strncmp(str, "s4_nohwsig", 10) == 0)
- acpi_no_s4_hw_signature();
+ acpi_check_s4_hw_signature(0);
#endif
if (strncmp(str, "nonvs", 5) == 0)
acpi_nvs_nosave();
diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index eaa47753b758..4dfbfc69db34 100644
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -877,11 +877,11 @@ static inline void acpi_sleep_syscore_init(void) {}
#ifdef CONFIG_HIBERNATION
static unsigned long s4_hardware_signature;
static struct acpi_table_facs *facs;
-static bool nosigcheck;
+static int sigcheck = -1; /* Default behaviour is just to warn */
-void __init acpi_no_s4_hw_signature(void)
+void __init acpi_check_s4_hw_signature(int check)
{
- nosigcheck = true;
+ sigcheck = check;
}
static int acpi_hibernation_begin(pm_message_t stage)
@@ -1009,12 +1009,28 @@ static void acpi_sleep_hibernate_setup(void)
hibernation_set_ops(old_suspend_ordering ?
&acpi_hibernation_ops_old : &acpi_hibernation_ops);
sleep_states[ACPI_STATE_S4] = 1;
- if (nosigcheck)
+ if (!sigcheck)
return;
acpi_get_table(ACPI_SIG_FACS, 1, (struct acpi_table_header **)&facs);
- if (facs)
+ if (facs) {
+ /*
+ * s4_hardware_signature is the local variable which is just
+ * used to warn about mismatch after we're attempting to
+ * resume (in violation of the ACPI specification.)
+ */
s4_hardware_signature = facs->hardware_signature;
+
+ if (sigcheck > 0) {
+ /*
+ * If we're actually obeying the ACPI specification
+ * then the signature is written out as part of the
+ * swsusp header, in order to allow the boot kernel
+ * to gracefully decline to resume.
+ */
+ swsusp_hardware_signature = facs->hardware_signature;
+ }
+ }
}
#else /* !CONFIG_HIBERNATION */
static inline void acpi_sleep_hibernate_setup(void) {}
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index b28f8790192a..6c0798db6bde 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -506,7 +506,7 @@ acpi_status acpi_release_memory(acpi_handle handle, struct resource *res,
int acpi_resources_are_enforced(void);
#ifdef CONFIG_HIBERNATION
-void __init acpi_no_s4_hw_signature(void);
+void __init acpi_check_s4_hw_signature(int check);
#endif
#ifdef CONFIG_PM_SLEEP
diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 8af13ba60c7e..5785d909c321 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -446,6 +446,7 @@ extern unsigned long get_safe_page(gfp_t gfp_mask);
extern asmlinkage int swsusp_arch_suspend(void);
extern asmlinkage int swsusp_arch_resume(void);
+extern u32 swsusp_hardware_signature;
extern void hibernation_set_ops(const struct platform_hibernation_ops *ops);
extern int hibernate(void);
extern bool system_entering_hibernation(void);
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 326f8d032eb5..b4f433943209 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -170,6 +170,7 @@ extern int swsusp_swap_in_use(void);
#define SF_PLATFORM_MODE 1
#define SF_NOCOMPRESS_MODE 2
#define SF_CRC32_MODE 4
+#define SF_HW_SIG 8
/* kernel/power/hibernate.c */
extern int swsusp_check(void);
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index ff326c2cb77b..ad10359030a4 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -36,6 +36,8 @@
#define HIBERNATE_SIG "S1SUSPEND"
+u32 swsusp_hardware_signature;
+
/*
* When reading an {un,}compressed image, we may restore pages in place,
* in which case some architectures need these pages cleaning before they
@@ -104,7 +106,8 @@ struct swap_map_handle {
struct swsusp_header {
char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int) -
- sizeof(u32)];
+ sizeof(u32) - sizeof(u32)];
+ u32 hw_sig;
u32 crc32;
sector_t image;
unsigned int flags; /* Flags to pass to the "boot" kernel */
@@ -312,7 +315,6 @@ static int hib_wait_io(struct hib_bio_batch *hb)
/*
* Saving part
*/
-
static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
{
int error;
@@ -324,6 +326,10 @@ static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
memcpy(swsusp_header->sig, HIBERNATE_SIG, 10);
swsusp_header->image = handle->first_sector;
+ if (swsusp_hardware_signature) {
+ swsusp_header->hw_sig = swsusp_hardware_signature;
+ flags |= SF_HW_SIG;
+ }
swsusp_header->flags = flags;
if (flags & SF_CRC32_MODE)
swsusp_header->crc32 = handle->crc32;
@@ -1537,6 +1543,12 @@ int swsusp_check(void)
} else {
error = -EINVAL;
}
+ if (!error && swsusp_header->flags & SF_HW_SIG &&
+ swsusp_header->hw_sig != swsusp_hardware_signature) {
+ pr_info("Suspend image hardware signature mismatch (%08x now %08x); aborting resume.\n",
+ swsusp_header->hw_sig, swsusp_hardware_signature);
+ error = -EINVAL;
+ }
put:
if (error)
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-04 03:38:44 +0000