diff options
Diffstat (limited to 'arch/powerpc/kexec/crash.c')
| -rw-r--r-- | arch/powerpc/kexec/crash.c | 86 |
1 files changed, 53 insertions, 33 deletions
diff --git a/arch/powerpc/kexec/crash.c b/arch/powerpc/kexec/crash.c index d488311efab1..ef5c2d25ec39 100644 --- a/arch/powerpc/kexec/crash.c +++ b/arch/powerpc/kexec/crash.c @@ -20,10 +20,10 @@ #include <asm/processor.h> #include <asm/machdep.h> #include <asm/kexec.h> -#include <asm/prom.h> #include <asm/smp.h> #include <asm/setjmp.h> #include <asm/debug.h> +#include <asm/interrupt.h> /* * The primary CPU waits a while for all secondary CPUs to enter. This is to @@ -40,6 +40,14 @@ #define REAL_MODE_TIMEOUT 10000 static int time_to_dump; + +/* + * In case of system reset, secondary CPUs enter crash_kexec_secondary with out + * having to send an IPI explicitly. So, indicate if the crash is via + * system reset to avoid sending another IPI. + */ +static int is_via_system_reset; + /* * crash_wake_offline should be set to 1 by platforms that intend to wake * up offline cpus prior to jumping to a kdump kernel. Currently powernv @@ -101,11 +109,11 @@ void crash_ipi_callback(struct pt_regs *regs) /* NOTREACHED */ } -static void crash_kexec_prepare_cpus(int cpu) +static void crash_kexec_prepare_cpus(void) { unsigned int msecs; - unsigned int ncpus = num_online_cpus() - 1;/* Excluding the panic cpu */ - int tries = 0; + volatile unsigned int ncpus = num_online_cpus() - 1;/* Excluding the panic cpu */ + volatile int tries = 0; int (*old_handler)(struct pt_regs *regs); printk(KERN_EMERG "Sending IPI to other CPUs\n"); @@ -113,7 +121,15 @@ static void crash_kexec_prepare_cpus(int cpu) if (crash_wake_offline) ncpus = num_present_cpus() - 1; - crash_send_ipi(crash_ipi_callback); + /* + * If we came in via system reset, secondaries enter via crash_kexec_secondary(). + * So, wait a while for the secondary CPUs to enter for that case. + * Else, send IPI to all other CPUs. + */ + if (is_via_system_reset) + mdelay(PRIMARY_TIMEOUT); + else + crash_send_ipi(crash_ipi_callback); smp_wmb(); again: @@ -202,7 +218,7 @@ void crash_kexec_secondary(struct pt_regs *regs) #else /* ! CONFIG_SMP */ -static void crash_kexec_prepare_cpus(int cpu) +static void crash_kexec_prepare_cpus(void) { /* * move the secondaries to us so that we can copy @@ -224,7 +240,7 @@ void crash_kexec_secondary(struct pt_regs *regs) /* wait for all the CPUs to hit real mode but timeout if they don't come in */ #if defined(CONFIG_SMP) && defined(CONFIG_PPC64) -static void __maybe_unused crash_kexec_wait_realmode(int cpu) +noinstr static void __maybe_unused crash_kexec_wait_realmode(int cpu) { unsigned int msecs; int i; @@ -248,6 +264,32 @@ static void __maybe_unused crash_kexec_wait_realmode(int cpu) static inline void crash_kexec_wait_realmode(int cpu) {} #endif /* CONFIG_SMP && CONFIG_PPC64 */ +void crash_kexec_prepare(void) +{ + /* Avoid hardlocking with irresponsive CPU holding logbuf_lock */ + printk_deferred_enter(); + + /* + * This function is only called after the system + * has panicked or is otherwise in a critical state. + * The minimum amount of code to allow a kexec'd kernel + * to run successfully needs to happen here. + * + * In practice this means stopping other cpus in + * an SMP system. + * The kernel is broken so disable interrupts. + */ + hard_irq_disable(); + + /* + * Make a note of crashing cpu. Will be used in machine_kexec + * such that another IPI will not be sent. + */ + crashing_cpu = smp_processor_id(); + + crash_kexec_prepare_cpus(); +} + /* * Register a function to be called on shutdown. Only use this if you * can't reset your device in the second kernel. @@ -308,35 +350,13 @@ EXPORT_SYMBOL(crash_shutdown_unregister); void default_machine_crash_shutdown(struct pt_regs *regs) { - unsigned int i; + volatile unsigned int i; int (*old_handler)(struct pt_regs *regs); - /* - * This function is only called after the system - * has panicked or is otherwise in a critical state. - * The minimum amount of code to allow a kexec'd kernel - * to run successfully needs to happen here. - * - * In practice this means stopping other cpus in - * an SMP system. - * The kernel is broken so disable interrupts. - */ - hard_irq_disable(); - - /* - * Make a note of crashing cpu. Will be used in machine_kexec - * such that another IPI will not be sent. - */ - crashing_cpu = smp_processor_id(); - - /* - * If we came in via system reset, wait a while for the secondary - * CPUs to enter. - */ - if (TRAP(regs) == 0x100) - mdelay(PRIMARY_TIMEOUT); + if (TRAP(regs) == INTERRUPT_SYSTEM_RESET) + is_via_system_reset = 1; - crash_kexec_prepare_cpus(crashing_cpu); + crash_smp_send_stop(); crash_save_cpu(regs, crashing_cpu); |