x86/mce/amd: Introduce deferred error interrupt handler

Deferred errors indicate error conditions that were not corrected, but
require no action from S/W (or action is optional).These errors provide
info about a latent UC MCE that can occur when a poisoned data is
consumed by the processor.

Processors that report these errors can be configured to generate APIC
interrupts to notify OS about the error.

Provide an interrupt handler in this patch so that OS can catch these
errors as and when they happen. Currently, we simply log the errors and
exit the handler as S/W action is not mandated.

Signed-off-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1430913538-1415-5-git-send-email-Aravind.Gopalakrishnan@amd.com
Signed-off-by: Borislav Petkov <bp@suse.de>

diff --git a/arch/x86/include/asm/entry_arch.h b/arch/x86/include/asm/entry_arch.h
index dc5fa661465f9a3fda9788c2f6caf9adc185a741..6da46dbaac8798d2d179b6ac3c7cbf32f32307ec 100644 (file)
--- a/arch/x86/include/asm/entry_arch.h
+++ b/arch/x86/include/asm/entry_arch.h
@@ -50,4 +50,7 @@ BUILD_INTERRUPT(thermal_interrupt,THERMAL_APIC_VECTOR)
 BUILD_INTERRUPT(threshold_interrupt,THRESHOLD_APIC_VECTOR)
 #endif
 
+#ifdef CONFIG_X86_MCE_AMD
+BUILD_INTERRUPT(deferred_error_interrupt, DEFERRED_ERROR_VECTOR)
+#endif
 #endif

diff --git a/arch/x86/include/asm/hardirq.h b/arch/x86/include/asm/hardirq.h
index 0f5fb6b6567e9c7e2856e86678189a82af0d853e..db9f536f482f5fcf58923e4b00e35aa2f7673267 100644 (file)
--- a/arch/x86/include/asm/hardirq.h
+++ b/arch/x86/include/asm/hardirq.h
@@ -33,6 +33,9 @@ typedef struct {
 #ifdef CONFIG_X86_MCE_THRESHOLD
        unsigned int irq_threshold_count;
 #endif
+#ifdef CONFIG_X86_MCE_AMD
+       unsigned int irq_deferred_error_count;
+#endif
 #if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
        unsigned int irq_hv_callback_count;
 #endif

diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h
index e9571ddabc4feb821ae04d47c9d6c3b509178344..f71e489d75379a0cab19161db3b5239bfc6245a0 100644 (file)
--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -73,6 +73,7 @@ extern asmlinkage void invalidate_interrupt31(void);
 extern asmlinkage void irq_move_cleanup_interrupt(void);
 extern asmlinkage void reboot_interrupt(void);
 extern asmlinkage void threshold_interrupt(void);
+extern asmlinkage void deferred_error_interrupt(void);
 
 extern asmlinkage void call_function_interrupt(void);
 extern asmlinkage void call_function_single_interrupt(void);
@@ -87,6 +88,7 @@ extern void trace_spurious_interrupt(void);
 extern void trace_thermal_interrupt(void);
 extern void trace_reschedule_interrupt(void);
 extern void trace_threshold_interrupt(void);
+extern void trace_deferred_error_interrupt(void);
 extern void trace_call_function_interrupt(void);
 extern void trace_call_function_single_interrupt(void);
 #define trace_irq_move_cleanup_interrupt  irq_move_cleanup_interrupt

diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h
index 666c89ec4bd7298c1114e7e220a3fee3ebe77bc8..026fc1e1599c03e7eb86b1fee65cb5cede917a35 100644 (file)
--- a/arch/x86/include/asm/irq_vectors.h
+++ b/arch/x86/include/asm/irq_vectors.h
@@ -113,6 +113,7 @@
 #define IRQ_WORK_VECTOR                        0xf6
 
 #define UV_BAU_MESSAGE                 0xf5
+#define DEFERRED_ERROR_VECTOR          0xf4
 
 /* Vector on which hypervisor callbacks will be delivered */
 #define HYPERVISOR_CALLBACK_VECTOR     0xf3

diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index 407ced642ac1fd7d0bc09fac39412f165b285235..6a3034a0a07217565c86af88e65b8768af11a518 100644 (file)
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -234,6 +234,9 @@ void do_machine_check(struct pt_regs *, long);
 extern void (*mce_threshold_vector)(void);
 extern void (*threshold_cpu_callback)(unsigned long action, unsigned int cpu);
 
+/* Deferred error interrupt handler */
+extern void (*deferred_error_int_vector)(void);
+
 /*
  * Thermal handler
  */

diff --git a/arch/x86/include/asm/trace/irq_vectors.h b/arch/x86/include/asm/trace/irq_vectors.h
index 4cab890007a7267ecc7ce148eaa1fdfbee4a49df..38a09a13a9bcdab24f0e2f08fd67f10cc25236dd 100644 (file)
--- a/arch/x86/include/asm/trace/irq_vectors.h
+++ b/arch/x86/include/asm/trace/irq_vectors.h
@@ -100,6 +100,12 @@ DEFINE_IRQ_VECTOR_EVENT(call_function_single);
  */
 DEFINE_IRQ_VECTOR_EVENT(threshold_apic);
 
+/*
+ * deferred_error_apic - called when entering/exiting a deferred apic interrupt
+ * vector handler
+ */
+DEFINE_IRQ_VECTOR_EVENT(deferred_error_apic);
+
 /*
  * thermal_apic - called when entering/exiting a thermal apic interrupt
  * vector handler

diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h
index 4e49d7dff78e5f30ffb6353c37277eaf6ab264aa..c5380bea2a36aaa533fd8aa28c58ff2ee68a7dec 100644 (file)
--- a/arch/x86/include/asm/traps.h
+++ b/arch/x86/include/asm/traps.h
@@ -108,7 +108,8 @@ extern int panic_on_unrecovered_nmi;
 void math_emulate(struct math_emu_info *);
 #ifndef CONFIG_X86_32
 asmlinkage void smp_thermal_interrupt(void);
-asmlinkage void mce_threshold_interrupt(void);
+asmlinkage void smp_threshold_interrupt(void);
+asmlinkage void smp_deferred_error_interrupt(void);
 #endif
 
 extern enum ctx_state ist_enter(struct pt_regs *regs);

diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c
index 607075726e105971e1b7d22d9ce9b71d841fcd95..2e7ebe7e1e80af337b42a0078b9060998261e501 100644 (file)
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
@@ -12,6 +12,8 @@
  *     - added support for AMD Family 0x10 processors
  *  May 2012
  *     - major scrubbing
+ *  May 2015
+ *     - add support for deferred error interrupts (Aravind Gopalakrishnan)
  *
  *  All MC4_MISCi registers are shared between multi-cores
  */
@@ -32,6 +34,7 @@
 #include <asm/idle.h>
 #include <asm/mce.h>
 #include <asm/msr.h>
+#include <asm/trace/irq_vectors.h>
 
 #define NR_BLOCKS         9
 #define THRESHOLD_MAX     0xFFF
@@ -47,6 +50,13 @@
 #define MASK_BLKPTR_LO    0xFF000000
 #define MCG_XBLK_ADDR     0xC0000400
 
+/* Deferred error settings */
+#define MSR_CU_DEF_ERR         0xC0000410
+#define MASK_DEF_LVTOFF                0x000000F0
+#define MASK_DEF_INT_TYPE      0x00000006
+#define DEF_LVT_OFF            0x2
+#define DEF_INT_TYPE_APIC      0x2
+
 static const char * const th_names[] = {
        "load_store",
        "insn_fetch",
@@ -60,6 +70,13 @@ static DEFINE_PER_CPU(struct threshold_bank **, threshold_banks);
 static DEFINE_PER_CPU(unsigned char, bank_map);        /* see which banks are on */
 
 static void amd_threshold_interrupt(void);
+static void amd_deferred_error_interrupt(void);
+
+static void default_deferred_error_interrupt(void)
+{
+       pr_err("Unexpected deferred interrupt at vector %x\n", DEFERRED_ERROR_VECTOR);
+}
+void (*deferred_error_int_vector)(void) = default_deferred_error_interrupt;
 
 /*
  * CPU Initialization
@@ -205,6 +222,39 @@ static int setup_APIC_mce(int reserved, int new)
        return reserved;
 }
 
+static int setup_APIC_deferred_error(int reserved, int new)
+{
+       if (reserved < 0 && !setup_APIC_eilvt(new, DEFERRED_ERROR_VECTOR,
+                                             APIC_EILVT_MSG_FIX, 0))
+               return new;
+
+       return reserved;
+}
+
+static void deferred_error_interrupt_enable(struct cpuinfo_x86 *c)
+{
+       u32 low = 0, high = 0;
+       int def_offset = -1, def_new;
+
+       if (rdmsr_safe(MSR_CU_DEF_ERR, &low, &high))
+               return;
+
+       def_new = (low & MASK_DEF_LVTOFF) >> 4;
+       if (!(low & MASK_DEF_LVTOFF)) {
+               pr_err(FW_BUG "Your BIOS is not setting up LVT offset 0x2 for deferred error IRQs correctly.\n");
+               def_new = DEF_LVT_OFF;
+               low = (low & ~MASK_DEF_LVTOFF) | (DEF_LVT_OFF << 4);
+       }
+
+       def_offset = setup_APIC_deferred_error(def_offset, def_new);
+       if ((def_offset == def_new) &&
+           (deferred_error_int_vector != amd_deferred_error_interrupt))
+               deferred_error_int_vector = amd_deferred_error_interrupt;
+
+       low = (low & ~MASK_DEF_INT_TYPE) | DEF_INT_TYPE_APIC;
+       wrmsr(MSR_CU_DEF_ERR, low, high);
+}
+
 /* cpu init entry point, called from mce.c with preempt off */
 void mce_amd_feature_init(struct cpuinfo_x86 *c)
 {
@@ -262,6 +312,9 @@ init:
                        mce_threshold_block_init(&b, offset);
                }
        }
+
+       if (mce_flags.succor)
+               deferred_error_interrupt_enable(c);
 }
 
 static void __log_error(unsigned int bank, bool threshold_err, u64 misc)
@@ -288,6 +341,46 @@ static void __log_error(unsigned int bank, bool threshold_err, u64 misc)
        wrmsrl(MSR_IA32_MCx_STATUS(bank), 0);
 }
 
+static inline void __smp_deferred_error_interrupt(void)
+{
+       inc_irq_stat(irq_deferred_error_count);
+       deferred_error_int_vector();
+}
+
+asmlinkage __visible void smp_deferred_error_interrupt(void)
+{
+       entering_irq();
+       __smp_deferred_error_interrupt();
+       exiting_ack_irq();
+}
+
+asmlinkage __visible void smp_trace_deferred_error_interrupt(void)
+{
+       entering_irq();
+       trace_deferred_error_apic_entry(DEFERRED_ERROR_VECTOR);
+       __smp_deferred_error_interrupt();
+       trace_deferred_error_apic_exit(DEFERRED_ERROR_VECTOR);
+       exiting_ack_irq();
+}
+
+/* APIC interrupt handler for deferred errors */
+static void amd_deferred_error_interrupt(void)
+{
+       u64 status;
+       unsigned int bank;
+
+       for (bank = 0; bank < mca_cfg.banks; ++bank) {
+               rdmsrl(MSR_IA32_MCx_STATUS(bank), status);
+
+               if (!(status & MCI_STATUS_VAL) ||
+                   !(status & MCI_STATUS_DEFERRED))
+                       continue;
+
+               __log_error(bank, false, 0);
+               break;
+       }
+}
+
 /*
  * APIC Interrupt Handler
  */

diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 02c2eff7478da6b5180eaf639010f93112e333c1..12aea85fe738bf3fab7a58f670a2eb4ddbdb3ec6 100644 (file)
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -935,6 +935,11 @@ apicinterrupt THRESHOLD_APIC_VECTOR \
        threshold_interrupt smp_threshold_interrupt
 #endif
 
+#ifdef CONFIG_X86_MCE_AMD
+apicinterrupt DEFERRED_ERROR_VECTOR \
+       deferred_error_interrupt smp_deferred_error_interrupt
+#endif
+
 #ifdef CONFIG_X86_THERMAL_VECTOR
 apicinterrupt THERMAL_APIC_VECTOR \
        thermal_interrupt smp_thermal_interrupt

diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index e5952c22553241e2ceea5d5fd6f1f7b758cc960e..590ed6c1bf51d1a5d34b09fadf4167de39250de7 100644 (file)
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -116,6 +116,12 @@ int arch_show_interrupts(struct seq_file *p, int prec)
                seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
        seq_puts(p, "  Threshold APIC interrupts\n");
 #endif
+#ifdef CONFIG_X86_MCE_AMD
+       seq_printf(p, "%*s: ", prec, "DFR");
+       for_each_online_cpu(j)
+               seq_printf(p, "%10u ", irq_stats(j)->irq_deferred_error_count);
+       seq_puts(p, "  Deferred Error APIC interrupts\n");
+#endif
 #ifdef CONFIG_X86_MCE
        seq_printf(p, "%*s: ", prec, "MCE");
        for_each_online_cpu(j)

diff --git a/arch/x86/kernel/irqinit.c b/arch/x86/kernel/irqinit.c
index cd10a64372647c3579ba6717db49c6cd63c6353a..d7ec6e7b2b5b329f1533fabec5d1db685fab09fa 100644 (file)
--- a/arch/x86/kernel/irqinit.c
+++ b/arch/x86/kernel/irqinit.c
@@ -135,6 +135,10 @@ static void __init apic_intr_init(void)
        alloc_intr_gate(THRESHOLD_APIC_VECTOR, threshold_interrupt);
 #endif
 
+#ifdef CONFIG_X86_MCE_AMD
+       alloc_intr_gate(DEFERRED_ERROR_VECTOR, deferred_error_interrupt);
+#endif
+
 #ifdef CONFIG_X86_LOCAL_APIC
        /* self generated IPI for local APIC timer */
        alloc_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 324ab524768756b1987efbee11f06ce3ba24562b..68b1d5979a46011af4137ae341129b4edb292bcd 100644 (file)
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -827,6 +827,11 @@ asmlinkage __visible void __attribute__((weak)) smp_threshold_interrupt(void)
 {
 }
 
+asmlinkage __visible void __attribute__((weak))
+smp_deferred_error_interrupt(void)
+{
+}
+
 /*
  * 'math_state_restore()' saves the current math information in the
  * old math state array, and gets the new ones from the current task