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-rw-r--r--arch/i386/kernel/crash.c36
-rw-r--r--arch/i386/kernel/traps.c17
-rw-r--r--arch/ppc/kernel/machine_kexec.c2
-rw-r--r--arch/ppc64/kernel/machine_kexec.c2
-rw-r--r--arch/s390/kernel/crash.c2
-rw-r--r--arch/x86_64/kernel/crash.c2
-rw-r--r--drivers/char/sysrq.c2
-rw-r--r--include/linux/kexec.h8
-rw-r--r--include/linux/reboot.h3
-rw-r--r--kernel/kexec.c13
-rw-r--r--kernel/panic.c2
11 files changed, 66 insertions, 23 deletions
diff --git a/arch/i386/kernel/crash.c b/arch/i386/kernel/crash.c
index a021681d21f8..8bdb4b6af0ff 100644
--- a/arch/i386/kernel/crash.c
+++ b/arch/i386/kernel/crash.c
@@ -100,12 +100,31 @@ static void crash_get_current_regs(struct pt_regs *regs)
regs->eip = (unsigned long)current_text_addr();
}
-static void crash_save_self(void)
+/* CPU does not save ss and esp on stack if execution is already
+ * running in kernel mode at the time of NMI occurrence. This code
+ * fixes it.
+ */
+static void crash_setup_regs(struct pt_regs *newregs, struct pt_regs *oldregs)
+{
+ memcpy(newregs, oldregs, sizeof(*newregs));
+ newregs->esp = (unsigned long)&(oldregs->esp);
+ __asm__ __volatile__("xorl %eax, %eax;");
+ __asm__ __volatile__ ("movw %%ss, %%ax;" :"=a"(newregs->xss));
+}
+
+/* We may have saved_regs from where the error came from
+ * or it is NULL if via a direct panic().
+ */
+static void crash_save_self(struct pt_regs *saved_regs)
{
struct pt_regs regs;
int cpu;
cpu = smp_processor_id();
- crash_get_current_regs(&regs);
+
+ if (saved_regs)
+ crash_setup_regs(&regs, saved_regs);
+ else
+ crash_get_current_regs(&regs);
crash_save_this_cpu(&regs, cpu);
}
@@ -124,15 +143,8 @@ static int crash_nmi_callback(struct pt_regs *regs, int cpu)
return 1;
local_irq_disable();
- /* CPU does not save ss and esp on stack if execution is already
- * running in kernel mode at the time of NMI occurrence. This code
- * fixes it.
- */
if (!user_mode(regs)) {
- memcpy(&fixed_regs, regs, sizeof(*regs));
- fixed_regs.esp = (unsigned long)&(regs->esp);
- __asm__ __volatile__("xorl %eax, %eax;");
- __asm__ __volatile__ ("movw %%ss, %%ax;" :"=a"(fixed_regs.xss));
+ crash_setup_regs(&fixed_regs, regs);
regs = &fixed_regs;
}
crash_save_this_cpu(regs, cpu);
@@ -184,7 +196,7 @@ static void nmi_shootdown_cpus(void)
}
#endif
-void machine_crash_shutdown(void)
+void machine_crash_shutdown(struct pt_regs *regs)
{
/* This function is only called after the system
* has paniced or is otherwise in a critical state.
@@ -204,5 +216,5 @@ void machine_crash_shutdown(void)
#if defined(CONFIG_X86_IO_APIC)
disable_IO_APIC();
#endif
- crash_save_self();
+ crash_save_self(regs);
}
diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c
index 207ea8ba7169..e458463ebc05 100644
--- a/arch/i386/kernel/traps.c
+++ b/arch/i386/kernel/traps.c
@@ -27,6 +27,7 @@
#include <linux/ptrace.h>
#include <linux/utsname.h>
#include <linux/kprobes.h>
+#include <linux/kexec.h>
#ifdef CONFIG_EISA
#include <linux/ioport.h>
@@ -294,6 +295,9 @@ bug:
printk("Kernel BUG\n");
}
+/* This is gone through when something in the kernel
+ * has done something bad and is about to be terminated.
+*/
void die(const char * str, struct pt_regs * regs, long err)
{
static struct {
@@ -341,6 +345,10 @@ void die(const char * str, struct pt_regs * regs, long err)
bust_spinlocks(0);
die.lock_owner = -1;
spin_unlock_irq(&die.lock);
+
+ if (kexec_should_crash(current))
+ crash_kexec(regs);
+
if (in_interrupt())
panic("Fatal exception in interrupt");
@@ -570,6 +578,15 @@ void die_nmi (struct pt_regs *regs, const char *msg)
console_silent();
spin_unlock(&nmi_print_lock);
bust_spinlocks(0);
+
+ /* If we are in kernel we are probably nested up pretty bad
+ * and might aswell get out now while we still can.
+ */
+ if (!user_mode(regs)) {
+ current->thread.trap_no = 2;
+ crash_kexec(regs);
+ }
+
do_exit(SIGSEGV);
}
diff --git a/arch/ppc/kernel/machine_kexec.c b/arch/ppc/kernel/machine_kexec.c
index 435ad9ea0a83..b82535357d6d 100644
--- a/arch/ppc/kernel/machine_kexec.c
+++ b/arch/ppc/kernel/machine_kexec.c
@@ -34,7 +34,7 @@ void machine_shutdown(void)
}
}
-void machine_crash_shutdown(void)
+void machine_crash_shutdown(struct pt_regs *regs)
{
if (ppc_md.machine_crash_shutdown) {
ppc_md.machine_crash_shutdown();
diff --git a/arch/ppc64/kernel/machine_kexec.c b/arch/ppc64/kernel/machine_kexec.c
index 217965d60a45..06b25b59c8a8 100644
--- a/arch/ppc64/kernel/machine_kexec.c
+++ b/arch/ppc64/kernel/machine_kexec.c
@@ -34,7 +34,7 @@ note_buf_t crash_notes[NR_CPUS];
* and if what it will achieve. Letting it be now to compile the code
* in generic kexec environment
*/
-void machine_crash_shutdown(void)
+void machine_crash_shutdown(struct pt_regs *regs)
{
/* do nothing right now */
/* smp_relase_cpus() if we want smp on panic kernel */
diff --git a/arch/s390/kernel/crash.c b/arch/s390/kernel/crash.c
index db38283c1f27..7bd169c58b0c 100644
--- a/arch/s390/kernel/crash.c
+++ b/arch/s390/kernel/crash.c
@@ -12,6 +12,6 @@
note_buf_t crash_notes[NR_CPUS];
-void machine_crash_shutdown(void)
+void machine_crash_shutdown(struct pt_regs *regs)
{
}
diff --git a/arch/x86_64/kernel/crash.c b/arch/x86_64/kernel/crash.c
index 6183bcb85257..d7fa4248501c 100644
--- a/arch/x86_64/kernel/crash.c
+++ b/arch/x86_64/kernel/crash.c
@@ -22,7 +22,7 @@
note_buf_t crash_notes[NR_CPUS];
-void machine_crash_shutdown(void)
+void machine_crash_shutdown(struct pt_regs *regs)
{
/* This function is only called after the system
* has paniced or is otherwise in a critical state.
diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c
index 53b2c8fab00e..af79805b5576 100644
--- a/drivers/char/sysrq.c
+++ b/drivers/char/sysrq.c
@@ -100,7 +100,7 @@ static struct sysrq_key_op sysrq_unraw_op = {
static void sysrq_handle_crashdump(int key, struct pt_regs *pt_regs,
struct tty_struct *tty)
{
- crash_kexec();
+ crash_kexec(pt_regs);
}
static struct sysrq_key_op sysrq_crashdump_op = {
.handler = sysrq_handle_crashdump,
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 0653a27c3d72..7383173a3a9c 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -99,7 +99,8 @@ extern asmlinkage long compat_sys_kexec_load(unsigned long entry,
unsigned long flags);
#endif
extern struct page *kimage_alloc_control_pages(struct kimage *image, unsigned int order);
-extern void crash_kexec(void);
+extern void crash_kexec(struct pt_regs *);
+int kexec_should_crash(struct task_struct *);
extern struct kimage *kexec_image;
#define KEXEC_ON_CRASH 0x00000001
@@ -123,6 +124,9 @@ extern struct kimage *kexec_image;
extern struct resource crashk_res;
#else /* !CONFIG_KEXEC */
-static inline void crash_kexec(void) { }
+struct pt_regs;
+struct task_struct;
+static inline void crash_kexec(struct pt_regs *regs) { }
+static inline int kexec_should_crash(struct task_struct *p) { return 0; }
#endif /* CONFIG_KEXEC */
#endif /* LINUX_KEXEC_H */
diff --git a/include/linux/reboot.h b/include/linux/reboot.h
index c5a05e16edb2..2d4dd23168dd 100644
--- a/include/linux/reboot.h
+++ b/include/linux/reboot.h
@@ -52,7 +52,8 @@ extern void machine_halt(void);
extern void machine_power_off(void);
extern void machine_shutdown(void);
-extern void machine_crash_shutdown(void);
+struct pt_regs;
+extern void machine_crash_shutdown(struct pt_regs *);
#endif
diff --git a/kernel/kexec.c b/kernel/kexec.c
index a0411b3bd54a..277f22afe74b 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -18,6 +18,8 @@
#include <linux/reboot.h>
#include <linux/syscalls.h>
#include <linux/ioport.h>
+#include <linux/hardirq.h>
+
#include <asm/page.h>
#include <asm/uaccess.h>
#include <asm/io.h>
@@ -32,6 +34,13 @@ struct resource crashk_res = {
.flags = IORESOURCE_BUSY | IORESOURCE_MEM
};
+int kexec_should_crash(struct task_struct *p)
+{
+ if (in_interrupt() || !p->pid || p->pid == 1 || panic_on_oops)
+ return 1;
+ return 0;
+}
+
/*
* When kexec transitions to the new kernel there is a one-to-one
* mapping between physical and virtual addresses. On processors
@@ -1010,7 +1019,7 @@ asmlinkage long compat_sys_kexec_load(unsigned long entry,
}
#endif
-void crash_kexec(void)
+void crash_kexec(struct pt_regs *regs)
{
struct kimage *image;
int locked;
@@ -1028,7 +1037,7 @@ void crash_kexec(void)
if (!locked) {
image = xchg(&kexec_crash_image, NULL);
if (image) {
- machine_crash_shutdown();
+ machine_crash_shutdown(regs);
machine_kexec(image);
}
xchg(&kexec_lock, 0);
diff --git a/kernel/panic.c b/kernel/panic.c
index 66f43d33cd80..74ba5f3e46c7 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -83,7 +83,7 @@ NORET_TYPE void panic(const char * fmt, ...)
* everything else.
* Do we want to call this before we try to display a message?
*/
- crash_kexec();
+ crash_kexec(NULL);
#ifdef CONFIG_SMP
/*
generated by cgit (git 2.34.1) at 2024-05-24 11:21:08 +0000