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authorRafael J. Wysocki <rjw@sisk.pl>2007-04-02 02:49:49 -0400
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-04-02 13:06:09 -0400
commit1d64b9cb1dc2a7cd521444e3d908adeccd026356 (patch)
tree31c6c7751b656e74b5ee05159c85154f710e8956 /arch
parent0c84ce268b69855919b6ac7edc8f11caf21e9c88 (diff)
[PATCH] Fix microcode-related suspend problem
Fix the regression resulting from the recent change of suspend code ordering that causes systems based on Intel x86 CPUs using the microcode driver to hang during the resume. The problem occurs since the microcode driver uses request_firmware() in its CPU hotplug notifier, which is called after tasks has been frozen and hangs. It can be fixed by telling the microcode driver to use the microcode stored in memory during the resume instead of trying to load it from disk. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Adrian Bunk <bunk@stusta.de> Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk> Cc: Pavel Machek <pavel@ucw.cz> Cc: Maxim <maximlevitsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch')
-rw-r--r--arch/i386/kernel/microcode.c71
1 files changed, 67 insertions, 4 deletions
diff --git a/arch/i386/kernel/microcode.c b/arch/i386/kernel/microcode.c
index b8f16633a6ec..cbe7ec8dbb9f 100644
--- a/arch/i386/kernel/microcode.c
+++ b/arch/i386/kernel/microcode.c
@@ -567,6 +567,53 @@ static int cpu_request_microcode(int cpu)
567 return error; 567 return error;
568} 568}
569 569
570static int apply_microcode_on_cpu(int cpu)
571{
572 struct cpuinfo_x86 *c = cpu_data + cpu;
573 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
574 cpumask_t old;
575 unsigned int val[2];
576 int err = 0;
577
578 if (!uci->mc)
579 return -EINVAL;
580
581 old = current->cpus_allowed;
582 set_cpus_allowed(current, cpumask_of_cpu(cpu));
583
584 /* Check if the microcode we have in memory matches the CPU */
585 if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
586 cpu_has(c, X86_FEATURE_IA64) || uci->sig != cpuid_eax(0x00000001))
587 err = -EINVAL;
588
589 if (!err && ((c->x86_model >= 5) || (c->x86 > 6))) {
590 /* get processor flags from MSR 0x17 */
591 rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
592 if (uci->pf != (1 << ((val[1] >> 18) & 7)))
593 err = -EINVAL;
594 }
595
596 if (!err) {
597 wrmsr(MSR_IA32_UCODE_REV, 0, 0);
598 /* see notes above for revision 1.07. Apparent chip bug */
599 sync_core();
600 /* get the current revision from MSR 0x8B */
601 rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
602 if (uci->rev != val[1])
603 err = -EINVAL;
604 }
605
606 if (!err)
607 apply_microcode(cpu);
608 else
609 printk(KERN_ERR "microcode: Could not apply microcode to CPU%d:"
610 " sig=0x%x, pf=0x%x, rev=0x%x\n",
611 cpu, uci->sig, uci->pf, uci->rev);
612
613 set_cpus_allowed(current, old);
614 return err;
615}
616
570static void microcode_init_cpu(int cpu) 617static void microcode_init_cpu(int cpu)
571{ 618{
572 cpumask_t old; 619 cpumask_t old;
@@ -577,7 +624,8 @@ static void microcode_init_cpu(int cpu)
577 set_cpus_allowed(current, cpumask_of_cpu(cpu)); 624 set_cpus_allowed(current, cpumask_of_cpu(cpu));
578 mutex_lock(&microcode_mutex); 625 mutex_lock(&microcode_mutex);
579 collect_cpu_info(cpu); 626 collect_cpu_info(cpu);
580 if (uci->valid && system_state == SYSTEM_RUNNING) 627 if (uci->valid && system_state == SYSTEM_RUNNING &&
628 !suspend_cpu_hotplug)
581 cpu_request_microcode(cpu); 629 cpu_request_microcode(cpu);
582 mutex_unlock(&microcode_mutex); 630 mutex_unlock(&microcode_mutex);
583 set_cpus_allowed(current, old); 631 set_cpus_allowed(current, old);
@@ -663,13 +711,24 @@ static int mc_sysdev_add(struct sys_device *sys_dev)
663 return 0; 711 return 0;
664 712
665 pr_debug("Microcode:CPU %d added\n", cpu); 713 pr_debug("Microcode:CPU %d added\n", cpu);
666 memset(uci, 0, sizeof(*uci)); 714 /* If suspend_cpu_hotplug is set, the system is resuming and we should
715 * use the data from before the suspend.
716 */
717 if (suspend_cpu_hotplug) {
718 err = apply_microcode_on_cpu(cpu);
719 if (err)
720 microcode_fini_cpu(cpu);
721 }
722 if (!uci->valid)
723 memset(uci, 0, sizeof(*uci));
667 724
668 err = sysfs_create_group(&sys_dev->kobj, &mc_attr_group); 725 err = sysfs_create_group(&sys_dev->kobj, &mc_attr_group);
669 if (err) 726 if (err)
670 return err; 727 return err;
671 728
672 microcode_init_cpu(cpu); 729 if (!uci->valid)
730 microcode_init_cpu(cpu);
731
673 return 0; 732 return 0;
674} 733}
675 734
@@ -680,7 +739,11 @@ static int mc_sysdev_remove(struct sys_device *sys_dev)
680 if (!cpu_online(cpu)) 739 if (!cpu_online(cpu))
681 return 0; 740 return 0;
682 pr_debug("Microcode:CPU %d removed\n", cpu); 741 pr_debug("Microcode:CPU %d removed\n", cpu);
683 microcode_fini_cpu(cpu); 742 /* If suspend_cpu_hotplug is set, the system is suspending and we should
743 * keep the microcode in memory for the resume.
744 */
745 if (!suspend_cpu_hotplug)
746 microcode_fini_cpu(cpu);
684 sysfs_remove_group(&sys_dev->kobj, &mc_attr_group); 747 sysfs_remove_group(&sys_dev->kobj, &mc_attr_group);
685 return 0; 748 return 0;
686} 749}