Re: 2.6.18-rc5-mm1

From: Andrew Morton
Date: Fri Sep 01 2006 - 21:28:03 EST

On Sat, 02 Sep 2006 03:00:47 +0200
Matthias Hentges <oe@xxxxxxxxxxx> wrote:

> 2.6.18-rc5-mm1 oopses on an Asus P5W DH Deluxe board, full dmesg
> attached.
> This did not happen in 2.6.18-rc4-mm3.
>
>
> BUG: unable to handle kernel NULL pointer dereference at virtual address
> 00000000
> printing eip:
> 00000000
> *pde = 00000000
> Oops: 0000 [#1]
> 4K_STACKS SMP
> last sysfs file:
> Modules linked in:
> CPU: 0
> EIP: 0060:[<00000000>] Not tainted VLI
> EFLAGS: 00010087 (2.6.18-rc5-mm1 #1)
> EIP is at rest_init+0x3feffd78/0x20
> eax: 000000da ebx: c04d5f78 ecx: c04d5f94 edx: c04d2f00
> esi: 000000da edi: 00000000 ebp: c04d2f00 esp: c0516ffc
> ds: 007b es: 007b ss: 0068
> Process swapper (pid: 0, ti=c0516000 task=c045c200 task.ti=c04d5000)
> Stack: c0105027
> Call Trace:
> [<c0105027>] do_IRQ+0x8a/0xac
> [<c01035a6>] common_interrupt+0x1a/0x20
> [<c0101a72>] mwait_idle_with_hints+0x36/0x3b
> [<c0101a83>] mwait_idle+0xc/0x1b
> [<c0101a26>] cpu_idle+0x5e/0x74
> [<c04db6fa>] start_kernel+0x363/0x36a
> =======================
> Code: Bad EIP value.
> EIP: [<00000000>] rest_init+0x3feffd78/0x20 SS:ESP 0068:c0516ffc
> <0>Kernel panic - not syncing: Fatal exception in interrupt
> BUG: warning at arch/i386/kernel/smp.c:547/smp_call_function()
> [<c010ca45>] smp_call_function+0x54/0xff
> [<c011a270>] printk+0x12/0x16
> [<c010cb03>] smp_send_stop+0x13/0x1c
> [<c0119480>] panic+0x49/0xd3
> [<c010410c>] die+0x273/0x28a
> [<c01126d4>] do_page_fault+0x40d/0x4db
> [<c01122c7>] do_page_fault+0x0/0x4db
> [<c03d1231>] error_code+0x39/0x40
> [<c013007b>] free_module+0x89/0xc3
> [<c0105027>] do_IRQ+0x8a/0xac
> [<c01035a6>] common_interrupt+0x1a/0x20
> [<c0101a72>] mwait_idle_with_hints+0x36/0x3b
> [<c0101a83>] mwait_idle+0xc/0x1b
> [<c0101a26>] cpu_idle+0x5e/0x74
> [<c04db6fa>] start_kernel+0x363/0x36a
> =======================

OK, thanks. That'll be acpi-mwait-c-state-fixes.patch. I've uploaded the
below revert patch to
ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.18-rc5/2.6.18-rc5-mm1/hot-fixes/


diff -puN arch/i386/kernel/acpi/cstate.c~revert-acpi-mwait-c-state-fixes arch/i386/kernel/acpi/cstate.c
--- a/arch/i386/kernel/acpi/cstate.c~revert-acpi-mwait-c-state-fixes
+++ a/arch/i386/kernel/acpi/cstate.c
@@ -10,7 +10,6 @@
#include <linux/module.h>
#include <linux/init.h>
#include <linux/acpi.h>
-#include <linux/cpu.h>

#include <acpi/processor.h>
#include <asm/acpi.h>
@@ -42,124 +41,5 @@ void acpi_processor_power_init_bm_check(
flags->bm_check = 1;
}
}
-EXPORT_SYMBOL(acpi_processor_power_init_bm_check);
-
-/* The code below handles cstate entry with monitor-mwait pair on Intel*/
-
-struct cstate_entry_s {
- struct {
- unsigned int eax;
- unsigned int ecx;
- } states[ACPI_PROCESSOR_MAX_POWER];
-};
-static struct cstate_entry_s *cpu_cstate_entry; /* per CPU ptr */
-
-static short mwait_supported[ACPI_PROCESSOR_MAX_POWER];
-
-#define MWAIT_SUBSTATE_MASK (0xf)
-#define MWAIT_SUBSTATE_SIZE (4)
-
-#define CPUID_MWAIT_LEAF (5)
-#define CPUID5_ECX_EXTENSIONS_SUPPORTED (0x1)
-#define CPUID5_ECX_INTERRUPT_BREAK (0x2)
-
-#define MWAIT_ECX_INTERRUPT_BREAK (0x1)
-
-#define NATIVE_CSTATE_BEYOND_HALT (2)
-
-int acpi_processor_ffh_cstate_probe(unsigned int cpu,
- struct acpi_processor_cx *cx, struct acpi_power_register *reg)
-{
- struct cstate_entry_s *percpu_entry;
- struct cpuinfo_x86 *c = cpu_data + cpu;
-
- cpumask_t saved_mask;
- int retval;
- unsigned int eax, ebx, ecx, edx;
- unsigned int edx_part;
- unsigned int cstate_type; /* C-state type and not ACPI C-state type */
- unsigned int num_cstate_subtype;
-
- if (!cpu_cstate_entry || c->cpuid_level < CPUID_MWAIT_LEAF )
- return -1;
-
- if (reg->bit_offset != NATIVE_CSTATE_BEYOND_HALT)
- return -1;
-
- percpu_entry = per_cpu_ptr(cpu_cstate_entry, cpu);
- percpu_entry->states[cx->index].eax = 0;
- percpu_entry->states[cx->index].ecx = 0;
-
- /* Make sure we are running on right CPU */
- saved_mask = current->cpus_allowed;
- retval = set_cpus_allowed(current, cpumask_of_cpu(cpu));
- if (retval)
- return -1;
-
- cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &edx);
-
- /* Check whether this particular cx_type (in CST) is supported or not */
- cstate_type = (cx->address >> MWAIT_SUBSTATE_SIZE) + 1;
- edx_part = edx >> (cstate_type * MWAIT_SUBSTATE_SIZE);
- num_cstate_subtype = edx_part & MWAIT_SUBSTATE_MASK;
-
- retval = 0;
- if (num_cstate_subtype < (cx->address & MWAIT_SUBSTATE_MASK)) {
- retval = -1;
- goto out;
- }

- /* mwait ecx extensions INTERRUPT_BREAK should be supported for C2/C3 */
- if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||
- !(ecx & CPUID5_ECX_INTERRUPT_BREAK)) {
- retval = -1;
- goto out;
- }
- percpu_entry->states[cx->index].ecx = MWAIT_ECX_INTERRUPT_BREAK;
-
- /* Use the hint in CST */
- percpu_entry->states[cx->index].eax = cx->address;
-
- if (!mwait_supported[cstate_type]) {
- mwait_supported[cstate_type] = 1;
- printk(KERN_DEBUG "Monitor-Mwait will be used to enter C-%d "
- "state\n", cx->type);
- }
-
-out:
- set_cpus_allowed(current, saved_mask);
- return retval;
-}
-EXPORT_SYMBOL_GPL(acpi_processor_ffh_cstate_probe);
-
-void acpi_processor_ffh_cstate_enter(struct acpi_processor_cx *cx)
-{
- unsigned int cpu = smp_processor_id();
- struct cstate_entry_s *percpu_entry;
-
- percpu_entry = per_cpu_ptr(cpu_cstate_entry, cpu);
- mwait_idle_with_hints(percpu_entry->states[cx->index].eax,
- percpu_entry->states[cx->index].ecx);
-}
-EXPORT_SYMBOL_GPL(acpi_processor_ffh_cstate_enter);
-
-static int __init ffh_cstate_init(void)
-{
- struct cpuinfo_x86 *c = &boot_cpu_data;
- if (c->x86_vendor != X86_VENDOR_INTEL)
- return -1;
-
- cpu_cstate_entry = alloc_percpu(struct cstate_entry_s);
- return 0;
-}
-
-static void __exit ffh_cstate_exit(void)
-{
- if (cpu_cstate_entry) {
- free_percpu(cpu_cstate_entry);
- cpu_cstate_entry = NULL;
- }
-}
-
-arch_initcall(ffh_cstate_init);
-__exitcall(ffh_cstate_exit);
+EXPORT_SYMBOL(acpi_processor_power_init_bm_check);
diff -puN arch/i386/kernel/process.c~revert-acpi-mwait-c-state-fixes arch/i386/kernel/process.c
--- a/arch/i386/kernel/process.c~revert-acpi-mwait-c-state-fixes
+++ a/arch/i386/kernel/process.c
@@ -236,28 +236,20 @@ EXPORT_SYMBOL_GPL(cpu_idle_wait);
* We execute MONITOR against need_resched and enter optimized wait state
* through MWAIT. Whenever someone changes need_resched, we would be woken
* up from MWAIT (without an IPI).
- *
- * New with Core Duo processors, MWAIT can take some hints based on CPU
- * capability.
*/
-void mwait_idle_with_hints(unsigned long eax, unsigned long ecx)
+static void mwait_idle(void)
{
- if (!need_resched()) {
+ local_irq_enable();
+
+ while (!need_resched()) {
__monitor((void *)&current_thread_info()->flags, 0, 0);
smp_mb();
- if (!need_resched())
- __mwait(eax, ecx);
+ if (need_resched())
+ break;
+ __mwait(0, 0);
}
}

-/* Default MONITOR/MWAIT with no hints, used for default C1 state */
-static void mwait_idle(void)
-{
- local_irq_enable();
- while (!need_resched())
- mwait_idle_with_hints(0, 0);
-}
-
void __devinit select_idle_routine(const struct cpuinfo_x86 *c)
{
if (cpu_has(c, X86_FEATURE_MWAIT)) {
diff -puN arch/x86_64/kernel/process.c~revert-acpi-mwait-c-state-fixes arch/x86_64/kernel/process.c
--- a/arch/x86_64/kernel/process.c~revert-acpi-mwait-c-state-fixes
+++ a/arch/x86_64/kernel/process.c
@@ -235,28 +235,20 @@ void cpu_idle (void)
* We execute MONITOR against need_resched and enter optimized wait state
* through MWAIT. Whenever someone changes need_resched, we would be woken
* up from MWAIT (without an IPI).
- *
- * New with Core Duo processors, MWAIT can take some hints based on CPU
- * capability.
*/
-void mwait_idle_with_hints(unsigned long eax, unsigned long ecx)
+static void mwait_idle(void)
{
- if (!need_resched()) {
+ local_irq_enable();
+
+ while (!need_resched()) {
__monitor((void *)&current_thread_info()->flags, 0, 0);
smp_mb();
- if (!need_resched())
- __mwait(eax, ecx);
+ if (need_resched())
+ break;
+ __mwait(0, 0);
}
}

-/* Default MONITOR/MWAIT with no hints, used for default C1 state */
-static void mwait_idle(void)
-{
- local_irq_enable();
- while (!need_resched())
- mwait_idle_with_hints(0,0);
-}
-
void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
{
static int printed;
diff -puN drivers/acpi/processor_idle.c~revert-acpi-mwait-c-state-fixes drivers/acpi/processor_idle.c
--- a/drivers/acpi/processor_idle.c~revert-acpi-mwait-c-state-fixes
+++ a/drivers/acpi/processor_idle.c
@@ -219,23 +219,6 @@ static void acpi_safe_halt(void)

static atomic_t c3_cpu_count;

-/* Common C-state entry for C2, C3, .. */
-static void acpi_cstate_enter(struct acpi_processor_cx *cstate)
-{
- if (cstate->space_id == ACPI_CSTATE_FFH) {
- /* Call into architectural FFH based C-state */
- acpi_processor_ffh_cstate_enter(cstate);
- } else {
- int unused;
- /* IO port based C-state */
- inb(cstate->address);
- /* Dummy wait op - must do something useless after P_LVL2 read
- because chipsets cannot guarantee that STPCLK# signal
- gets asserted in time to freeze execution properly. */
- unused = inl(acpi_fadt.xpm_tmr_blk.address);
- }
-}
-
static void acpi_processor_idle(void)
{
struct acpi_processor *pr = NULL;
@@ -378,7 +361,11 @@ static void acpi_processor_idle(void)
/* Get start time (ticks) */
t1 = inl(acpi_fadt.xpm_tmr_blk.address);
/* Invoke C2 */
- acpi_cstate_enter(cx);
+ inb(cx->address);
+ /* Dummy wait op - must do something useless after P_LVL2 read
+ because chipsets cannot guarantee that STPCLK# signal
+ gets asserted in time to freeze execution properly. */
+ t2 = inl(acpi_fadt.xpm_tmr_blk.address);
/* Get end time (ticks) */
t2 = inl(acpi_fadt.xpm_tmr_blk.address);

@@ -414,7 +401,9 @@ static void acpi_processor_idle(void)
/* Get start time (ticks) */
t1 = inl(acpi_fadt.xpm_tmr_blk.address);
/* Invoke C3 */
- acpi_cstate_enter(cx);
+ inb(cx->address);
+ /* Dummy wait op (see above) */
+ t2 = inl(acpi_fadt.xpm_tmr_blk.address);
/* Get end time (ticks) */
t2 = inl(acpi_fadt.xpm_tmr_blk.address);
if (pr->flags.bm_check) {
@@ -639,16 +628,20 @@ static int acpi_processor_get_power_info
return 0;
}

-static int acpi_processor_get_power_info_default(struct acpi_processor *pr)
+static int acpi_processor_get_power_info_default_c1(struct acpi_processor *pr)
{
- if (!pr->power.states[ACPI_STATE_C1].valid) {
- /* set the first C-State to C1 */
- /* all processors need to support C1 */
- pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1;
- pr->power.states[ACPI_STATE_C1].valid = 1;
- }
- /* the C0 state only exists as a filler in our array */
+
+ /* Zero initialize all the C-states info. */
+ memset(pr->power.states, 0, sizeof(pr->power.states));
+
+ /* set the first C-State to C1 */
+ pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1;
+
+ /* the C0 state only exists as a filler in our array,
+ * and all processors need to support C1 */
pr->power.states[ACPI_STATE_C0].valid = 1;
+ pr->power.states[ACPI_STATE_C1].valid = 1;
+
return 0;
}

@@ -665,7 +658,12 @@ static int acpi_processor_get_power_info
if (nocst)
return -ENODEV;

- current_count = 0;
+ current_count = 1;
+
+ /* Zero initialize C2 onwards and prepare for fresh CST lookup */
+ for (i = 2; i < ACPI_PROCESSOR_MAX_POWER; i++)
+ memset(&(pr->power.states[i]), 0,
+ sizeof(struct acpi_processor_cx));

status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer);
if (ACPI_FAILURE(status)) {
@@ -720,39 +718,22 @@ static int acpi_processor_get_power_info
(reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE))
continue;

+ cx.address = (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) ?
+ 0 : reg->address;
+
/* There should be an easy way to extract an integer... */
obj = (union acpi_object *)&(element->package.elements[1]);
if (obj->type != ACPI_TYPE_INTEGER)
continue;

cx.type = obj->integer.value;
- /*
- * Some buggy BIOSes won't list C1 in _CST -
- * Let acpi_processor_get_power_info_default() handle them later
- */
- if (i == 1 && cx.type != ACPI_STATE_C1)
- current_count++;

- cx.address = reg->address;
- cx.index = current_count + 1;
+ if ((cx.type != ACPI_STATE_C1) &&
+ (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO))
+ continue;

- cx.space_id = ACPI_CSTATE_SYSTEMIO;
- if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
- if (acpi_processor_ffh_cstate_probe
- (pr->id, &cx, reg) == 0) {
- cx.space_id = ACPI_CSTATE_FFH;
- } else if (cx.type != ACPI_STATE_C1) {
- /*
- * C1 is a special case where FIXED_HARDWARE
- * can be handled in non-MWAIT way as well.
- * In that case, save this _CST entry info.
- * That is, we retain space_id of SYSTEM_IO for
- * halt based C1.
- * Otherwise, ignore this info and continue.
- */
- continue;
- }
- }
+ if ((cx.type < ACPI_STATE_C2) || (cx.type > ACPI_STATE_C3))
+ continue;

obj = (union acpi_object *)&(element->package.elements[2]);
if (obj->type != ACPI_TYPE_INTEGER)
@@ -957,18 +938,12 @@ static int acpi_processor_get_power_info
/* NOTE: the idle thread may not be running while calling
* this function */

- /* Zero initialize all the C-states info. */
- memset(pr->power.states, 0, sizeof(pr->power.states));
-
+ /* Adding C1 state */
+ acpi_processor_get_power_info_default_c1(pr);
result = acpi_processor_get_power_info_cst(pr);
if (result == -ENODEV)
acpi_processor_get_power_info_fadt(pr);

- if (result)
- return result;
-
- acpi_processor_get_power_info_default(pr);
-
pr->power.count = acpi_processor_power_verify(pr);

/*
diff -puN include/acpi/pdc_intel.h~revert-acpi-mwait-c-state-fixes include/acpi/pdc_intel.h
--- a/include/acpi/pdc_intel.h~revert-acpi-mwait-c-state-fixes
+++ a/include/acpi/pdc_intel.h
@@ -13,7 +13,6 @@
#define ACPI_PDC_SMP_C_SWCOORD (0x0040)
#define ACPI_PDC_SMP_T_SWCOORD (0x0080)
#define ACPI_PDC_C_C1_FFH (0x0100)
-#define ACPI_PDC_C_C2C3_FFH (0x0200)

#define ACPI_PDC_EST_CAPABILITY_SMP (ACPI_PDC_SMP_C1PT | \
ACPI_PDC_C_C1_HALT | \
@@ -24,10 +23,8 @@
ACPI_PDC_SMP_P_SWCOORD | \
ACPI_PDC_P_FFH)

-#define ACPI_PDC_C_CAPABILITY_SMP (ACPI_PDC_SMP_C2C3 | \
- ACPI_PDC_SMP_C1PT | \
- ACPI_PDC_C_C1_HALT | \
- ACPI_PDC_C_C1_FFH | \
- ACPI_PDC_C_C2C3_FFH)
+#define ACPI_PDC_C_CAPABILITY_SMP (ACPI_PDC_SMP_C2C3 | \
+ ACPI_PDC_SMP_C1PT | \
+ ACPI_PDC_C_C1_HALT)

#endif /* __PDC_INTEL_H__ */
diff -puN include/acpi/processor.h~revert-acpi-mwait-c-state-fixes include/acpi/processor.h
--- a/include/acpi/processor.h~revert-acpi-mwait-c-state-fixes
+++ a/include/acpi/processor.h
@@ -29,9 +29,6 @@
#define DOMAIN_COORD_TYPE_SW_ANY 0xfd
#define DOMAIN_COORD_TYPE_HW_ALL 0xfe

-#define ACPI_CSTATE_SYSTEMIO (0)
-#define ACPI_CSTATE_FFH (1)
-
/* Power Management */

struct acpi_processor_cx;
@@ -61,8 +58,6 @@ struct acpi_processor_cx {
u8 valid;
u8 type;
u32 address;
- u8 space_id;
- u8 index;
u32 latency;
u32 latency_ticks;
u32 power;
@@ -211,9 +206,6 @@ void arch_acpi_processor_init_pdc(struct
#ifdef ARCH_HAS_POWER_INIT
void acpi_processor_power_init_bm_check(struct acpi_processor_flags *flags,
unsigned int cpu);
-int acpi_processor_ffh_cstate_probe(unsigned int cpu,
- struct acpi_processor_cx *cx, struct acpi_power_register *reg);
-void acpi_processor_ffh_cstate_enter(struct acpi_processor_cx *cstate);
#else
static inline void acpi_processor_power_init_bm_check(struct
acpi_processor_flags
@@ -222,16 +214,6 @@ static inline void acpi_processor_power_
flags->bm_check = 1;
return;
}
-static inline int acpi_processor_ffh_cstate_probe(unsigned int cpu,
- struct acpi_processor_cx *cx, struct acpi_power_register *reg)
-{
- return -1;
-}
-static inline void acpi_processor_ffh_cstate_enter(
- struct acpi_processor_cx *cstate)
-{
- return;
-}
#endif

/* in processor_perflib.c */
diff -puN include/asm-i386/processor.h~revert-acpi-mwait-c-state-fixes include/asm-i386/processor.h
--- a/include/asm-i386/processor.h~revert-acpi-mwait-c-state-fixes
+++ a/include/asm-i386/processor.h
@@ -306,8 +306,6 @@ static inline void __mwait(unsigned long
: :"a" (eax), "c" (ecx));
}

-extern void mwait_idle_with_hints(unsigned long eax, unsigned long ecx);
-
/* from system description table in BIOS. Mostly for MCA use, but
others may find it useful. */
extern unsigned int machine_id;
diff -puN include/asm-x86_64/processor.h~revert-acpi-mwait-c-state-fixes include/asm-x86_64/processor.h
--- a/include/asm-x86_64/processor.h~revert-acpi-mwait-c-state-fixes
+++ a/include/asm-x86_64/processor.h
@@ -475,8 +475,6 @@ static inline void __mwait(unsigned long
: :"a" (eax), "c" (ecx));
}

-extern void mwait_idle_with_hints(unsigned long eax, unsigned long ecx);
-
#define stack_current() \
({ \
struct thread_info *ti; \
_


--
VGER BF report: H 0
-
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