forked from luck/tmp_suning_uos_patched
d368514c30
The FWNMI code uses a global buffer without any locks to read the RTAS error information. If two CPUs take a machine check at once then we will corrupt this buffer. Since most FWNMI rtas messages are not of the extended type, we can create a 64bit percpu buffer and use it where possible. If we do receive an extended RTAS log then we fall back to the old behaviour of using the global buffer. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
348 lines
10 KiB
C
348 lines
10 KiB
C
/*
|
|
* Copyright (C) 2001 Dave Engebretsen IBM Corporation
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*/
|
|
|
|
/* Change Activity:
|
|
* 2001/09/21 : engebret : Created with minimal EPOW and HW exception support.
|
|
* End Change Activity
|
|
*/
|
|
|
|
#include <linux/errno.h>
|
|
#include <linux/threads.h>
|
|
#include <linux/kernel_stat.h>
|
|
#include <linux/signal.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/ioport.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/timex.h>
|
|
#include <linux/init.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/random.h>
|
|
#include <linux/sysrq.h>
|
|
#include <linux/bitops.h>
|
|
|
|
#include <asm/uaccess.h>
|
|
#include <asm/system.h>
|
|
#include <asm/io.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/irq.h>
|
|
#include <asm/cache.h>
|
|
#include <asm/prom.h>
|
|
#include <asm/ptrace.h>
|
|
#include <asm/machdep.h>
|
|
#include <asm/rtas.h>
|
|
#include <asm/udbg.h>
|
|
#include <asm/firmware.h>
|
|
|
|
#include "pseries.h"
|
|
|
|
static unsigned char ras_log_buf[RTAS_ERROR_LOG_MAX];
|
|
static DEFINE_SPINLOCK(ras_log_buf_lock);
|
|
|
|
static char global_mce_data_buf[RTAS_ERROR_LOG_MAX];
|
|
static DEFINE_PER_CPU(__u64, mce_data_buf);
|
|
|
|
static int ras_get_sensor_state_token;
|
|
static int ras_check_exception_token;
|
|
|
|
#define EPOW_SENSOR_TOKEN 9
|
|
#define EPOW_SENSOR_INDEX 0
|
|
|
|
static irqreturn_t ras_epow_interrupt(int irq, void *dev_id);
|
|
static irqreturn_t ras_error_interrupt(int irq, void *dev_id);
|
|
|
|
|
|
/*
|
|
* Initialize handlers for the set of interrupts caused by hardware errors
|
|
* and power system events.
|
|
*/
|
|
static int __init init_ras_IRQ(void)
|
|
{
|
|
struct device_node *np;
|
|
|
|
ras_get_sensor_state_token = rtas_token("get-sensor-state");
|
|
ras_check_exception_token = rtas_token("check-exception");
|
|
|
|
/* Internal Errors */
|
|
np = of_find_node_by_path("/event-sources/internal-errors");
|
|
if (np != NULL) {
|
|
request_event_sources_irqs(np, ras_error_interrupt,
|
|
"RAS_ERROR");
|
|
of_node_put(np);
|
|
}
|
|
|
|
/* EPOW Events */
|
|
np = of_find_node_by_path("/event-sources/epow-events");
|
|
if (np != NULL) {
|
|
request_event_sources_irqs(np, ras_epow_interrupt, "RAS_EPOW");
|
|
of_node_put(np);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
__initcall(init_ras_IRQ);
|
|
|
|
/*
|
|
* Handle power subsystem events (EPOW).
|
|
*
|
|
* Presently we just log the event has occurred. This should be fixed
|
|
* to examine the type of power failure and take appropriate action where
|
|
* the time horizon permits something useful to be done.
|
|
*/
|
|
static irqreturn_t ras_epow_interrupt(int irq, void *dev_id)
|
|
{
|
|
int status = 0xdeadbeef;
|
|
int state = 0;
|
|
int critical;
|
|
|
|
status = rtas_call(ras_get_sensor_state_token, 2, 2, &state,
|
|
EPOW_SENSOR_TOKEN, EPOW_SENSOR_INDEX);
|
|
|
|
if (state > 3)
|
|
critical = 1; /* Time Critical */
|
|
else
|
|
critical = 0;
|
|
|
|
spin_lock(&ras_log_buf_lock);
|
|
|
|
status = rtas_call(ras_check_exception_token, 6, 1, NULL,
|
|
RTAS_VECTOR_EXTERNAL_INTERRUPT,
|
|
irq_map[irq].hwirq,
|
|
RTAS_EPOW_WARNING | RTAS_POWERMGM_EVENTS,
|
|
critical, __pa(&ras_log_buf),
|
|
rtas_get_error_log_max());
|
|
|
|
udbg_printf("EPOW <0x%lx 0x%x 0x%x>\n",
|
|
*((unsigned long *)&ras_log_buf), status, state);
|
|
printk(KERN_WARNING "EPOW <0x%lx 0x%x 0x%x>\n",
|
|
*((unsigned long *)&ras_log_buf), status, state);
|
|
|
|
/* format and print the extended information */
|
|
log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, 0);
|
|
|
|
spin_unlock(&ras_log_buf_lock);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/*
|
|
* Handle hardware error interrupts.
|
|
*
|
|
* RTAS check-exception is called to collect data on the exception. If
|
|
* the error is deemed recoverable, we log a warning and return.
|
|
* For nonrecoverable errors, an error is logged and we stop all processing
|
|
* as quickly as possible in order to prevent propagation of the failure.
|
|
*/
|
|
static irqreturn_t ras_error_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct rtas_error_log *rtas_elog;
|
|
int status = 0xdeadbeef;
|
|
int fatal;
|
|
|
|
spin_lock(&ras_log_buf_lock);
|
|
|
|
status = rtas_call(ras_check_exception_token, 6, 1, NULL,
|
|
RTAS_VECTOR_EXTERNAL_INTERRUPT,
|
|
irq_map[irq].hwirq,
|
|
RTAS_INTERNAL_ERROR, 1 /*Time Critical */,
|
|
__pa(&ras_log_buf),
|
|
rtas_get_error_log_max());
|
|
|
|
rtas_elog = (struct rtas_error_log *)ras_log_buf;
|
|
|
|
if ((status == 0) && (rtas_elog->severity >= RTAS_SEVERITY_ERROR_SYNC))
|
|
fatal = 1;
|
|
else
|
|
fatal = 0;
|
|
|
|
/* format and print the extended information */
|
|
log_error(ras_log_buf, ERR_TYPE_RTAS_LOG, fatal);
|
|
|
|
if (fatal) {
|
|
udbg_printf("Fatal HW Error <0x%lx 0x%x>\n",
|
|
*((unsigned long *)&ras_log_buf), status);
|
|
printk(KERN_EMERG "Error: Fatal hardware error <0x%lx 0x%x>\n",
|
|
*((unsigned long *)&ras_log_buf), status);
|
|
|
|
#ifndef DEBUG_RTAS_POWER_OFF
|
|
/* Don't actually power off when debugging so we can test
|
|
* without actually failing while injecting errors.
|
|
* Error data will not be logged to syslog.
|
|
*/
|
|
ppc_md.power_off();
|
|
#endif
|
|
} else {
|
|
udbg_printf("Recoverable HW Error <0x%lx 0x%x>\n",
|
|
*((unsigned long *)&ras_log_buf), status);
|
|
printk(KERN_WARNING
|
|
"Warning: Recoverable hardware error <0x%lx 0x%x>\n",
|
|
*((unsigned long *)&ras_log_buf), status);
|
|
}
|
|
|
|
spin_unlock(&ras_log_buf_lock);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/*
|
|
* Some versions of FWNMI place the buffer inside the 4kB page starting at
|
|
* 0x7000. Other versions place it inside the rtas buffer. We check both.
|
|
*/
|
|
#define VALID_FWNMI_BUFFER(A) \
|
|
((((A) >= 0x7000) && ((A) < 0x7ff0)) || \
|
|
(((A) >= rtas.base) && ((A) < (rtas.base + rtas.size - 16))))
|
|
|
|
/*
|
|
* Get the error information for errors coming through the
|
|
* FWNMI vectors. The pt_regs' r3 will be updated to reflect
|
|
* the actual r3 if possible, and a ptr to the error log entry
|
|
* will be returned if found.
|
|
*
|
|
* If the RTAS error is not of the extended type, then we put it in a per
|
|
* cpu 64bit buffer. If it is the extended type we use global_mce_data_buf.
|
|
*
|
|
* The global_mce_data_buf does not have any locks or protection around it,
|
|
* if a second machine check comes in, or a system reset is done
|
|
* before we have logged the error, then we will get corruption in the
|
|
* error log. This is preferable over holding off on calling
|
|
* ibm,nmi-interlock which would result in us checkstopping if a
|
|
* second machine check did come in.
|
|
*/
|
|
static struct rtas_error_log *fwnmi_get_errinfo(struct pt_regs *regs)
|
|
{
|
|
unsigned long *savep;
|
|
struct rtas_error_log *h, *errhdr = NULL;
|
|
|
|
if (!VALID_FWNMI_BUFFER(regs->gpr[3])) {
|
|
printk(KERN_ERR "FWNMI: corrupt r3\n");
|
|
return NULL;
|
|
}
|
|
|
|
savep = __va(regs->gpr[3]);
|
|
regs->gpr[3] = savep[0]; /* restore original r3 */
|
|
|
|
/* If it isn't an extended log we can use the per cpu 64bit buffer */
|
|
h = (struct rtas_error_log *)&savep[1];
|
|
if (!h->extended) {
|
|
memcpy(&__get_cpu_var(mce_data_buf), h, sizeof(__u64));
|
|
errhdr = (struct rtas_error_log *)&__get_cpu_var(mce_data_buf);
|
|
} else {
|
|
int len;
|
|
|
|
len = max_t(int, 8+h->extended_log_length, RTAS_ERROR_LOG_MAX);
|
|
memset(global_mce_data_buf, 0, RTAS_ERROR_LOG_MAX);
|
|
memcpy(global_mce_data_buf, h, len);
|
|
errhdr = (struct rtas_error_log *)global_mce_data_buf;
|
|
}
|
|
|
|
return errhdr;
|
|
}
|
|
|
|
/* Call this when done with the data returned by FWNMI_get_errinfo.
|
|
* It will release the saved data area for other CPUs in the
|
|
* partition to receive FWNMI errors.
|
|
*/
|
|
static void fwnmi_release_errinfo(void)
|
|
{
|
|
int ret = rtas_call(rtas_token("ibm,nmi-interlock"), 0, 1, NULL);
|
|
if (ret != 0)
|
|
printk(KERN_ERR "FWNMI: nmi-interlock failed: %d\n", ret);
|
|
}
|
|
|
|
int pSeries_system_reset_exception(struct pt_regs *regs)
|
|
{
|
|
if (fwnmi_active) {
|
|
struct rtas_error_log *errhdr = fwnmi_get_errinfo(regs);
|
|
if (errhdr) {
|
|
/* XXX Should look at FWNMI information */
|
|
}
|
|
fwnmi_release_errinfo();
|
|
}
|
|
return 0; /* need to perform reset */
|
|
}
|
|
|
|
/*
|
|
* See if we can recover from a machine check exception.
|
|
* This is only called on power4 (or above) and only via
|
|
* the Firmware Non-Maskable Interrupts (fwnmi) handler
|
|
* which provides the error analysis for us.
|
|
*
|
|
* Return 1 if corrected (or delivered a signal).
|
|
* Return 0 if there is nothing we can do.
|
|
*/
|
|
static int recover_mce(struct pt_regs *regs, struct rtas_error_log *err)
|
|
{
|
|
int recovered = 0;
|
|
|
|
if (!(regs->msr & MSR_RI)) {
|
|
/* If MSR_RI isn't set, we cannot recover */
|
|
recovered = 0;
|
|
|
|
} else if (err->disposition == RTAS_DISP_FULLY_RECOVERED) {
|
|
/* Platform corrected itself */
|
|
recovered = 1;
|
|
|
|
} else if (err->disposition == RTAS_DISP_LIMITED_RECOVERY) {
|
|
/* Platform corrected itself but could be degraded */
|
|
printk(KERN_ERR "MCE: limited recovery, system may "
|
|
"be degraded\n");
|
|
recovered = 1;
|
|
|
|
} else if (user_mode(regs) && !is_global_init(current) &&
|
|
err->severity == RTAS_SEVERITY_ERROR_SYNC) {
|
|
|
|
/*
|
|
* If we received a synchronous error when in userspace
|
|
* kill the task. Firmware may report details of the fail
|
|
* asynchronously, so we can't rely on the target and type
|
|
* fields being valid here.
|
|
*/
|
|
printk(KERN_ERR "MCE: uncorrectable error, killing task "
|
|
"%s:%d\n", current->comm, current->pid);
|
|
|
|
_exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
|
|
recovered = 1;
|
|
}
|
|
|
|
log_error((char *)err, ERR_TYPE_RTAS_LOG, 0);
|
|
|
|
return recovered;
|
|
}
|
|
|
|
/*
|
|
* Handle a machine check.
|
|
*
|
|
* Note that on Power 4 and beyond Firmware Non-Maskable Interrupts (fwnmi)
|
|
* should be present. If so the handler which called us tells us if the
|
|
* error was recovered (never true if RI=0).
|
|
*
|
|
* On hardware prior to Power 4 these exceptions were asynchronous which
|
|
* means we can't tell exactly where it occurred and so we can't recover.
|
|
*/
|
|
int pSeries_machine_check_exception(struct pt_regs *regs)
|
|
{
|
|
struct rtas_error_log *errp;
|
|
|
|
if (fwnmi_active) {
|
|
errp = fwnmi_get_errinfo(regs);
|
|
fwnmi_release_errinfo();
|
|
if (errp && recover_mce(regs, errp))
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|