Linus,
Please pull the latest x86-apic-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-apic-for-linus
# HEAD: ea7bdc65bca8cf837a63e0ff7b75daed83222511 x86/apic: Plug racy xAPIC
access of CPU hotplug code
An xAPIC CPU hotplug race fix, plus cleanups and minor fixes.
Thanks,
Ingo
------------------>
David Rientjes (4):
x86/apic: Only use default_wait_for_init_deassert()
x86/apic: Switch wait_for_init_deassert() to a bool flag
x86/apic: Remove unused function prototypes
x86/apic: Always define nox2apic and define it as initdata
Jan Kiszka (1):
x86/apic: Plug racy xAPIC access of CPU hotplug code
arch/x86/include/asm/apic.h | 14 +-------------
arch/x86/kernel/apic/apic.c | 13 ++++++++++---
arch/x86/kernel/apic/apic_flat_64.c | 4 ++--
arch/x86/kernel/apic/apic_noop.c | 3 +--
arch/x86/kernel/apic/apic_numachip.c | 2 +-
arch/x86/kernel/apic/bigsmp_32.c | 3 +--
arch/x86/kernel/apic/es7000_32.c | 12 ++----------
arch/x86/kernel/apic/numaq_32.c | 3 +--
arch/x86/kernel/apic/probe_32.c | 3 +--
arch/x86/kernel/apic/summit_32.c | 3 +--
arch/x86/kernel/apic/x2apic_cluster.c | 2 +-
arch/x86/kernel/apic/x2apic_phys.c | 2 +-
arch/x86/kernel/apic/x2apic_uv_x.c | 2 +-
arch/x86/kernel/smpboot.c | 16 ++++++++++++----
14 files changed, 36 insertions(+), 46 deletions(-)
diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index 1d2091a..19b0eba 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -93,9 +93,6 @@ static inline int is_vsmp_box(void)
return 0;
}
#endif
-extern void xapic_wait_icr_idle(void);
-extern u32 safe_xapic_wait_icr_idle(void);
-extern void xapic_icr_write(u32, u32);
extern int setup_profiling_timer(unsigned int);
static inline void native_apic_mem_write(u32 reg, u32 v)
@@ -184,7 +181,6 @@ extern int x2apic_phys;
extern int x2apic_preenabled;
extern void check_x2apic(void);
extern void enable_x2apic(void);
-extern void x2apic_icr_write(u32 low, u32 id);
static inline int x2apic_enabled(void)
{
u64 msr;
@@ -221,7 +217,6 @@ static inline void x2apic_force_phys(void)
{
}
-#define nox2apic 0
#define x2apic_preenabled 0
#define x2apic_supported() 0
#endif
@@ -351,7 +346,7 @@ struct apic {
int trampoline_phys_low;
int trampoline_phys_high;
- void (*wait_for_init_deassert)(atomic_t *deassert);
+ bool wait_for_init_deassert;
void (*smp_callin_clear_local_apic)(void);
void (*inquire_remote_apic)(int apicid);
@@ -517,13 +512,6 @@ extern int default_cpu_present_to_apicid(int mps_cpu);
extern int default_check_phys_apicid_present(int phys_apicid);
#endif
-static inline void default_wait_for_init_deassert(atomic_t *deassert)
-{
- while (!atomic_read(deassert))
- cpu_relax();
- return;
-}
-
extern void generic_bigsmp_probe(void);
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 7f26c9a..53e2053 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -133,6 +133,10 @@ static inline void imcr_apic_to_pic(void)
* +1=force-enable
*/
static int force_enable_local_apic __initdata;
+
+/* Control whether x2APIC mode is enabled or not */
+static bool nox2apic __initdata;
+
/*
* APIC command line parameters
*/
@@ -162,8 +166,7 @@ int x2apic_mode;
/* x2apic enabled before OS handover */
int x2apic_preenabled;
static int x2apic_disabled;
-static int nox2apic;
-static __init int setup_nox2apic(char *str)
+static int __init setup_nox2apic(char *str)
{
if (x2apic_enabled()) {
int apicid = native_apic_msr_read(APIC_ID);
@@ -178,7 +181,7 @@ static __init int setup_nox2apic(char *str)
} else
setup_clear_cpu_cap(X86_FEATURE_X2APIC);
- nox2apic = 1;
+ nox2apic = true;
return 0;
}
@@ -283,8 +286,12 @@ u32 native_safe_apic_wait_icr_idle(void)
void native_apic_icr_write(u32 low, u32 id)
{
+ unsigned long flags;
+
+ local_irq_save(flags);
apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
apic_write(APIC_ICR, low);
+ local_irq_restore(flags);
}
u64 native_apic_icr_read(void)
diff --git a/arch/x86/kernel/apic/apic_flat_64.c
b/arch/x86/kernel/apic/apic_flat_64.c
index 2c621a6..7c1b294 100644
--- a/arch/x86/kernel/apic/apic_flat_64.c
+++ b/arch/x86/kernel/apic/apic_flat_64.c
@@ -198,7 +198,7 @@ static struct apic apic_flat = {
.trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW,
.trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH,
- .wait_for_init_deassert = NULL,
+ .wait_for_init_deassert = false,
.smp_callin_clear_local_apic = NULL,
.inquire_remote_apic = default_inquire_remote_apic,
@@ -314,7 +314,7 @@ static struct apic apic_physflat = {
.trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW,
.trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH,
- .wait_for_init_deassert = NULL,
+ .wait_for_init_deassert = false,
.smp_callin_clear_local_apic = NULL,
.inquire_remote_apic = default_inquire_remote_apic,
diff --git a/arch/x86/kernel/apic/apic_noop.c b/arch/x86/kernel/apic/apic_noop.c
index 191ce75..8c7c982 100644
--- a/arch/x86/kernel/apic/apic_noop.c
+++ b/arch/x86/kernel/apic/apic_noop.c
@@ -172,8 +172,7 @@ struct apic apic_noop = {
.trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW,
.trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH,
- .wait_for_init_deassert = NULL,
-
+ .wait_for_init_deassert = false,
.smp_callin_clear_local_apic = NULL,
.inquire_remote_apic = NULL,
diff --git a/arch/x86/kernel/apic/apic_numachip.c
b/arch/x86/kernel/apic/apic_numachip.c
index 3e67f9e..a5b45df 100644
--- a/arch/x86/kernel/apic/apic_numachip.c
+++ b/arch/x86/kernel/apic/apic_numachip.c
@@ -248,7 +248,7 @@ static const struct apic apic_numachip __refconst = {
.wakeup_secondary_cpu = numachip_wakeup_secondary,
.trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW,
.trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH,
- .wait_for_init_deassert = NULL,
+ .wait_for_init_deassert = false,
.smp_callin_clear_local_apic = NULL,
.inquire_remote_apic = NULL, /* REMRD not supported */
diff --git a/arch/x86/kernel/apic/bigsmp_32.c b/arch/x86/kernel/apic/bigsmp_32.c
index d50e364..e4840aa 100644
--- a/arch/x86/kernel/apic/bigsmp_32.c
+++ b/arch/x86/kernel/apic/bigsmp_32.c
@@ -199,8 +199,7 @@ static struct apic apic_bigsmp = {
.trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW,
.trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH,
- .wait_for_init_deassert = default_wait_for_init_deassert,
-
+ .wait_for_init_deassert = true,
.smp_callin_clear_local_apic = NULL,
.inquire_remote_apic = default_inquire_remote_apic,
diff --git a/arch/x86/kernel/apic/es7000_32.c b/arch/x86/kernel/apic/es7000_32.c
index c552247..6f8f8b3 100644
--- a/arch/x86/kernel/apic/es7000_32.c
+++ b/arch/x86/kernel/apic/es7000_32.c
@@ -394,12 +394,6 @@ static void es7000_enable_apic_mode(void)
WARN(1, "Command failed, status = %x\n", mip_status);
}
-static void es7000_wait_for_init_deassert(atomic_t *deassert)
-{
- while (!atomic_read(deassert))
- cpu_relax();
-}
-
static unsigned int es7000_get_apic_id(unsigned long x)
{
return (x >> 24) & 0xFF;
@@ -658,8 +652,7 @@ static struct apic __refdata apic_es7000_cluster = {
.trampoline_phys_low = 0x467,
.trampoline_phys_high = 0x469,
- .wait_for_init_deassert = NULL,
-
+ .wait_for_init_deassert = false,
/* Nothing to do for most platforms, since cleared by the INIT cycle: */
.smp_callin_clear_local_apic = NULL,
.inquire_remote_apic = default_inquire_remote_apic,
@@ -722,8 +715,7 @@ static struct apic __refdata apic_es7000 = {
.trampoline_phys_low = 0x467,
.trampoline_phys_high = 0x469,
- .wait_for_init_deassert = es7000_wait_for_init_deassert,
-
+ .wait_for_init_deassert = true,
/* Nothing to do for most platforms, since cleared by the INIT cycle: */
.smp_callin_clear_local_apic = NULL,
.inquire_remote_apic = default_inquire_remote_apic,
diff --git a/arch/x86/kernel/apic/numaq_32.c b/arch/x86/kernel/apic/numaq_32.c
index 1e42e8f..030ea1c 100644
--- a/arch/x86/kernel/apic/numaq_32.c
+++ b/arch/x86/kernel/apic/numaq_32.c
@@ -505,8 +505,7 @@ static struct apic __refdata apic_numaq = {
.trampoline_phys_high = NUMAQ_TRAMPOLINE_PHYS_HIGH,
/* We don't do anything here because we use NMI's to boot instead */
- .wait_for_init_deassert = NULL,
-
+ .wait_for_init_deassert = false,
.smp_callin_clear_local_apic = numaq_smp_callin_clear_local_apic,
.inquire_remote_apic = NULL,
diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c
index eb35ef9..cceb352 100644
--- a/arch/x86/kernel/apic/probe_32.c
+++ b/arch/x86/kernel/apic/probe_32.c
@@ -119,8 +119,7 @@ static struct apic apic_default = {
.trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW,
.trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH,
- .wait_for_init_deassert = default_wait_for_init_deassert,
-
+ .wait_for_init_deassert = true,
.smp_callin_clear_local_apic = NULL,
.inquire_remote_apic = default_inquire_remote_apic,
diff --git a/arch/x86/kernel/apic/summit_32.c b/arch/x86/kernel/apic/summit_32.c
index 00146f9..b656128 100644
--- a/arch/x86/kernel/apic/summit_32.c
+++ b/arch/x86/kernel/apic/summit_32.c
@@ -532,8 +532,7 @@ static struct apic apic_summit = {
.trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW,
.trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH,
- .wait_for_init_deassert = default_wait_for_init_deassert,
-
+ .wait_for_init_deassert = true,
.smp_callin_clear_local_apic = NULL,
.inquire_remote_apic = default_inquire_remote_apic,
diff --git a/arch/x86/kernel/apic/x2apic_cluster.c
b/arch/x86/kernel/apic/x2apic_cluster.c
index cac85ee..e66766b 100644
--- a/arch/x86/kernel/apic/x2apic_cluster.c
+++ b/arch/x86/kernel/apic/x2apic_cluster.c
@@ -279,7 +279,7 @@ static struct apic apic_x2apic_cluster = {
.trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW,
.trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH,
- .wait_for_init_deassert = NULL,
+ .wait_for_init_deassert = false,
.smp_callin_clear_local_apic = NULL,
.inquire_remote_apic = NULL,
diff --git a/arch/x86/kernel/apic/x2apic_phys.c
b/arch/x86/kernel/apic/x2apic_phys.c
index de231e3..6d600eb 100644
--- a/arch/x86/kernel/apic/x2apic_phys.c
+++ b/arch/x86/kernel/apic/x2apic_phys.c
@@ -133,7 +133,7 @@ static struct apic apic_x2apic_phys = {
.trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW,
.trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH,
- .wait_for_init_deassert = NULL,
+ .wait_for_init_deassert = false,
.smp_callin_clear_local_apic = NULL,
.inquire_remote_apic = NULL,
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c
b/arch/x86/kernel/apic/x2apic_uv_x.c
index d263b13..7834389 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -396,7 +396,7 @@ static struct apic __refdata apic_x2apic_uv_x = {
.wakeup_secondary_cpu = uv_wakeup_secondary,
.trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW,
.trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH,
- .wait_for_init_deassert = NULL,
+ .wait_for_init_deassert = false,
.smp_callin_clear_local_apic = NULL,
.inquire_remote_apic = NULL,
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index a32da80..60179ec 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -122,8 +122,9 @@ static void smp_callin(void)
* Since CPU0 is not wakened up by INIT, it doesn't wait for the IPI.
*/
cpuid = smp_processor_id();
- if (apic->wait_for_init_deassert && cpuid != 0)
- apic->wait_for_init_deassert(&init_deasserted);
+ if (apic->wait_for_init_deassert && cpuid)
+ while (!atomic_read(&init_deasserted))
+ cpu_relax();
/*
* (This works even if the APIC is not enabled.)
@@ -701,11 +702,15 @@ wakeup_cpu_via_init_nmi(int cpu, unsigned long start_ip,
int apicid,
int id;
int boot_error;
+ preempt_disable();
+
/*
* Wake up AP by INIT, INIT, STARTUP sequence.
*/
- if (cpu)
- return wakeup_secondary_cpu_via_init(apicid, start_ip);
+ if (cpu) {
+ boot_error = wakeup_secondary_cpu_via_init(apicid, start_ip);
+ goto out;
+ }
/*
* Wake up BSP by nmi.
@@ -725,6 +730,9 @@ wakeup_cpu_via_init_nmi(int cpu, unsigned long start_ip,
int apicid,
boot_error = wakeup_secondary_cpu_via_nmi(id, start_ip);
}
+out:
+ preempt_enable();
+
return boot_error;
}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
