From 692174b97d5b871f4b0f648b1fb17aa37b955876 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 2 May 2007 19:27:09 +0200 Subject: [PATCH] i386: Initialize esp0 properly all the time Whenever we schedule, __switch_to calls load_esp0 which does: tss->esp0 = thread->esp0; This is never initialized for the initial thread (ie "swapper"), so when we're scheduling that, we end up setting esp0 to 0. This is fine: the swapper never leaves ring 0, so this field is never used. lguest, however, gets upset that we're trying to used an unmapped page as our kernel stack. Rather than work around it there, let's initialize it. Signed-off-by: Rusty Russell Signed-off-by: Andi Kleen Cc: Andi Kleen Signed-off-by: Andrew Morton --- include/asm-i386/processor.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/asm-i386/processor.h') diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h index 11bf899de8aa..01ae0ffcf236 100644 --- a/include/asm-i386/processor.h +++ b/include/asm-i386/processor.h @@ -421,6 +421,7 @@ struct thread_struct { }; #define INIT_THREAD { \ + .esp0 = sizeof(init_stack) + (long)&init_stack, \ .vm86_info = NULL, \ .sysenter_cs = __KERNEL_CS, \ .io_bitmap_ptr = NULL, \ -- cgit v1.2.2 From ae1ee11be77f51cedb6c569887dddc70c163ab6d Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 2 May 2007 19:27:10 +0200 Subject: [PATCH] i386: Use per-cpu variables for GDT, PDA Allocating PDA and GDT at boot is a pain. Using simple per-cpu variables adds happiness (although we need the GDT page-aligned for Xen, which we do in a followup patch). [akpm@linux-foundation.org: build fix] Signed-off-by: Rusty Russell Signed-off-by: Andi Kleen Cc: Andi Kleen Signed-off-by: Andrew Morton --- include/asm-i386/processor.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/asm-i386/processor.h') diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h index 01ae0ffcf236..cd940befef53 100644 --- a/include/asm-i386/processor.h +++ b/include/asm-i386/processor.h @@ -743,7 +743,7 @@ extern unsigned long boot_option_idle_override; extern void enable_sep_cpu(void); extern int sysenter_setup(void); -extern int init_gdt(int cpu, struct task_struct *idle); +extern void init_gdt(int cpu, struct task_struct *idle); extern void cpu_set_gdt(int); extern void secondary_cpu_init(void); -- cgit v1.2.2 From bf50467204b435421d8de33ad080fa46c6f3d50b Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 2 May 2007 19:27:10 +0200 Subject: [PATCH] i386: Use per-cpu GDT immediately upon boot Now we are no longer dynamically allocating the GDT, we don't need the "cpu_gdt_table" at all: we can switch straight from "boot_gdt_table" to the per-cpu GDT. This means initializing the cpu_gdt array in C. The boot CPU uses the per-cpu var directly, then in smp_prepare_cpus() it switches to the per-cpu copy just allocated. For secondary CPUs, the early_gdt_descr is set to point directly to their per-cpu copy. For UP the code is very simple: it keeps using the "per-cpu" GDT as per SMP, but we never have to move. Signed-off-by: Rusty Russell Signed-off-by: Andi Kleen Cc: Andi Kleen Signed-off-by: Andrew Morton --- include/asm-i386/processor.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/asm-i386/processor.h') diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h index cd940befef53..b25a2f5b5375 100644 --- a/include/asm-i386/processor.h +++ b/include/asm-i386/processor.h @@ -743,7 +743,6 @@ extern unsigned long boot_option_idle_override; extern void enable_sep_cpu(void); extern int sysenter_setup(void); -extern void init_gdt(int cpu, struct task_struct *idle); extern void cpu_set_gdt(int); extern void secondary_cpu_init(void); -- cgit v1.2.2 From d2cbcc49e2bfd6eaa44d7e4e5e5f171aaa5ec80d Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 2 May 2007 19:27:10 +0200 Subject: [PATCH] i386: clean up cpu_init() We now have cpu_init() and secondary_cpu_init() doing nothing but calling _cpu_init() with the same arguments. Rename _cpu_init() to cpu_init() and use it as a replcement for secondary_cpu_init(). Signed-off-by: Rusty Russell Signed-off-by: Andi Kleen Cc: Andi Kleen Signed-off-by: Andrew Morton --- include/asm-i386/processor.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/asm-i386/processor.h') diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h index b25a2f5b5375..80f7e8a1e878 100644 --- a/include/asm-i386/processor.h +++ b/include/asm-i386/processor.h @@ -744,6 +744,6 @@ extern void enable_sep_cpu(void); extern int sysenter_setup(void); extern void cpu_set_gdt(int); -extern void secondary_cpu_init(void); +extern void cpu_init(void); #endif /* __ASM_I386_PROCESSOR_H */ -- cgit v1.2.2 From 90a0a06aa81692028864c21f981905fda46b1208 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 2 May 2007 19:27:10 +0200 Subject: [PATCH] i386: rationalize paravirt wrappers paravirt.c used to implement native versions of all low-level functions. Far cleaner is to have the native versions exposed in the headers and as inline native_XXX, and if !CONFIG_PARAVIRT, then simply #define XXX native_XXX. There are several nice side effects: 1) write_dt_entry() now takes the correct "struct Xgt_desc_struct *" not "void *". 2) load_TLS is reintroduced to the for loop, not manually unrolled with a #error in case the bounds ever change. 3) Macros become inlines, with type checking. 4) Access to the native versions is trivial for KVM, lguest, Xen and others who might want it. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Rusty Russell Signed-off-by: Andi Kleen Cc: Andi Kleen Cc: Avi Kivity Signed-off-by: Andrew Morton --- include/asm-i386/processor.h | 94 ++++++++++++++++++++++++++++++++++---------- 1 file changed, 73 insertions(+), 21 deletions(-) (limited to 'include/asm-i386/processor.h') diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h index 80f7e8a1e878..96edfdfe32d1 100644 --- a/include/asm-i386/processor.h +++ b/include/asm-i386/processor.h @@ -147,7 +147,7 @@ static inline void detect_ht(struct cpuinfo_x86 *c) {} #define X86_EFLAGS_VIP 0x00100000 /* Virtual Interrupt Pending */ #define X86_EFLAGS_ID 0x00200000 /* CPUID detection flag */ -static inline fastcall void native_cpuid(unsigned int *eax, unsigned int *ebx, +static inline void native_cpuid(unsigned int *eax, unsigned int *ebx, unsigned int *ecx, unsigned int *edx) { /* ecx is often an input as well as an output. */ @@ -545,13 +545,7 @@ static inline void rep_nop(void) #define cpu_relax() rep_nop() -#ifdef CONFIG_PARAVIRT -#include -#else -#define paravirt_enabled() 0 -#define __cpuid native_cpuid - -static inline void load_esp0(struct tss_struct *tss, struct thread_struct *thread) +static inline void native_load_esp0(struct tss_struct *tss, struct thread_struct *thread) { tss->esp0 = thread->esp0; /* This can only happen when SEP is enabled, no need to test "SEP"arately */ @@ -561,24 +555,60 @@ static inline void load_esp0(struct tss_struct *tss, struct thread_struct *threa } } -/* - * These special macros can be used to get or set a debugging register - */ -#define get_debugreg(var, register) \ - __asm__("movl %%db" #register ", %0" \ - :"=r" (var)) -#define set_debugreg(value, register) \ - __asm__("movl %0,%%db" #register \ - : /* no output */ \ - :"r" (value)) -#define set_iopl_mask native_set_iopl_mask -#endif /* CONFIG_PARAVIRT */ +static inline unsigned long native_get_debugreg(int regno) +{ + unsigned long val = 0; /* Damn you, gcc! */ + + switch (regno) { + case 0: + asm("movl %%db0, %0" :"=r" (val)); break; + case 1: + asm("movl %%db1, %0" :"=r" (val)); break; + case 2: + asm("movl %%db2, %0" :"=r" (val)); break; + case 3: + asm("movl %%db3, %0" :"=r" (val)); break; + case 6: + asm("movl %%db6, %0" :"=r" (val)); break; + case 7: + asm("movl %%db7, %0" :"=r" (val)); break; + default: + BUG(); + } + return val; +} + +static inline void native_set_debugreg(int regno, unsigned long value) +{ + switch (regno) { + case 0: + asm("movl %0,%%db0" : /* no output */ :"r" (value)); + break; + case 1: + asm("movl %0,%%db1" : /* no output */ :"r" (value)); + break; + case 2: + asm("movl %0,%%db2" : /* no output */ :"r" (value)); + break; + case 3: + asm("movl %0,%%db3" : /* no output */ :"r" (value)); + break; + case 6: + asm("movl %0,%%db6" : /* no output */ :"r" (value)); + break; + case 7: + asm("movl %0,%%db7" : /* no output */ :"r" (value)); + break; + default: + BUG(); + } +} /* * Set IOPL bits in EFLAGS from given mask */ -static fastcall inline void native_set_iopl_mask(unsigned mask) +static inline void native_set_iopl_mask(unsigned mask) { unsigned int reg; __asm__ __volatile__ ("pushfl;" @@ -591,6 +621,28 @@ static fastcall inline void native_set_iopl_mask(unsigned mask) : "i" (~X86_EFLAGS_IOPL), "r" (mask)); } +#ifdef CONFIG_PARAVIRT +#include +#else +#define paravirt_enabled() 0 +#define __cpuid native_cpuid + +static inline void load_esp0(struct tss_struct *tss, struct thread_struct *thread) +{ + native_load_esp0(tss, thread); +} + +/* + * These special macros can be used to get or set a debugging register + */ +#define get_debugreg(var, register) \ + (var) = native_get_debugreg(register) +#define set_debugreg(value, register) \ + native_set_debugreg(register, value) + +#define set_iopl_mask native_set_iopl_mask +#endif /* CONFIG_PARAVIRT */ + /* * Generic CPUID function * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx -- cgit v1.2.2 From b4531e863dbd06b5d336afefdb37483b690dea59 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 2 May 2007 19:27:10 +0200 Subject: [PATCH] i386: Use X86_EFLAGS_IF in irqflags.h. Move X86_EFLAGS_IF et al out to a new header: processor-flags.h, so we can include it from irqflags.h and use it in raw_irqs_disabled_flags(). As a side-effect, we could now use these flags in .S files. Signed-off-by: Rusty Russell Signed-off-by: Andi Kleen --- include/asm-i386/processor.h | 22 +--------------------- 1 file changed, 1 insertion(+), 21 deletions(-) (limited to 'include/asm-i386/processor.h') diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h index 96edfdfe32d1..11838df88603 100644 --- a/include/asm-i386/processor.h +++ b/include/asm-i386/processor.h @@ -21,6 +21,7 @@ #include #include #include +#include /* flag for disabling the tsc */ extern int tsc_disable; @@ -126,27 +127,6 @@ extern void detect_ht(struct cpuinfo_x86 *c); static inline void detect_ht(struct cpuinfo_x86 *c) {} #endif -/* - * EFLAGS bits - */ -#define X86_EFLAGS_CF 0x00000001 /* Carry Flag */ -#define X86_EFLAGS_PF 0x00000004 /* Parity Flag */ -#define X86_EFLAGS_AF 0x00000010 /* Auxillary carry Flag */ -#define X86_EFLAGS_ZF 0x00000040 /* Zero Flag */ -#define X86_EFLAGS_SF 0x00000080 /* Sign Flag */ -#define X86_EFLAGS_TF 0x00000100 /* Trap Flag */ -#define X86_EFLAGS_IF 0x00000200 /* Interrupt Flag */ -#define X86_EFLAGS_DF 0x00000400 /* Direction Flag */ -#define X86_EFLAGS_OF 0x00000800 /* Overflow Flag */ -#define X86_EFLAGS_IOPL 0x00003000 /* IOPL mask */ -#define X86_EFLAGS_NT 0x00004000 /* Nested Task */ -#define X86_EFLAGS_RF 0x00010000 /* Resume Flag */ -#define X86_EFLAGS_VM 0x00020000 /* Virtual Mode */ -#define X86_EFLAGS_AC 0x00040000 /* Alignment Check */ -#define X86_EFLAGS_VIF 0x00080000 /* Virtual Interrupt Flag */ -#define X86_EFLAGS_VIP 0x00100000 /* Virtual Interrupt Pending */ -#define X86_EFLAGS_ID 0x00200000 /* CPUID detection flag */ - static inline void native_cpuid(unsigned int *eax, unsigned int *ebx, unsigned int *ecx, unsigned int *edx) { -- cgit v1.2.2 From a6c4e076ee4c1ea670e4faa55814e63dd08e3f29 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 2 May 2007 19:27:12 +0200 Subject: [PATCH] i386: clean up identify_cpu identify_cpu() is used to identify both the boot CPU and secondary CPUs, but it performs some actions which only apply to the boot CPU. Those functions are therefore really __init functions, but because they're called by identify_cpu(), they must be marked __cpuinit. This patch splits identify_cpu() into identify_boot_cpu() and identify_secondary_cpu(), and calls the appropriate init functions from each. Also, identify_boot_cpu() and all the functions it dominates are marked __init. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Andi Kleen --- include/asm-i386/processor.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/asm-i386/processor.h') diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h index 11838df88603..9d895cc2f312 100644 --- a/include/asm-i386/processor.h +++ b/include/asm-i386/processor.h @@ -116,7 +116,8 @@ extern char ignore_fpu_irq; void __init cpu_detect(struct cpuinfo_x86 *c); -extern void identify_cpu(struct cpuinfo_x86 *); +extern void identify_boot_cpu(void); +extern void identify_secondary_cpu(struct cpuinfo_x86 *); extern void print_cpu_info(struct cpuinfo_x86 *); extern unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c); extern unsigned short num_cache_leaves; -- cgit v1.2.2 From f039b754714a422959027cb18bb33760eb8153f0 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 2 May 2007 19:27:12 +0200 Subject: [PATCH] x86: Don't use MWAIT on AMD Family 10 It doesn't put the CPU into deeper sleep states, so it's better to use the standard idle loop to save power. But allow to reenable it anyways for benchmarking. I also removed the obsolete idle=halt on i386 Cc: andreas.herrmann@amd.com Signed-off-by: Andi Kleen --- include/asm-i386/processor.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/asm-i386/processor.h') diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h index 9d895cc2f312..882d3f8fbbac 100644 --- a/include/asm-i386/processor.h +++ b/include/asm-i386/processor.h @@ -779,4 +779,6 @@ extern int sysenter_setup(void); extern void cpu_set_gdt(int); extern void cpu_init(void); +extern int force_mwait; + #endif /* __ASM_I386_PROCESSOR_H */ -- cgit v1.2.2 From 4bc5aa91fb1e544ad37805520030a0d9fc6e11d3 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Wed, 2 May 2007 19:27:12 +0200 Subject: [PATCH] x86: Clean up x86 control register and MSR macros (corrected) This patch is based on Rusty's recent cleanup of the EFLAGS-related macros; it extends the same kind of cleanup to control registers and MSRs. It also unifies these between i386 and x86-64; at least with regards to MSRs, the two had definitely gotten out of sync. Signed-off-by: H. Peter Anvin Signed-off-by: Andi Kleen --- include/asm-i386/processor.h | 35 ----------------------------------- 1 file changed, 35 deletions(-) (limited to 'include/asm-i386/processor.h') diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h index 882d3f8fbbac..77e263267aa6 100644 --- a/include/asm-i386/processor.h +++ b/include/asm-i386/processor.h @@ -142,21 +142,6 @@ static inline void native_cpuid(unsigned int *eax, unsigned int *ebx, #define load_cr3(pgdir) write_cr3(__pa(pgdir)) -/* - * Intel CPU features in CR4 - */ -#define X86_CR4_VME 0x0001 /* enable vm86 extensions */ -#define X86_CR4_PVI 0x0002 /* virtual interrupts flag enable */ -#define X86_CR4_TSD 0x0004 /* disable time stamp at ipl 3 */ -#define X86_CR4_DE 0x0008 /* enable debugging extensions */ -#define X86_CR4_PSE 0x0010 /* enable page size extensions */ -#define X86_CR4_PAE 0x0020 /* enable physical address extensions */ -#define X86_CR4_MCE 0x0040 /* Machine check enable */ -#define X86_CR4_PGE 0x0080 /* enable global pages */ -#define X86_CR4_PCE 0x0100 /* enable performance counters at ipl 3 */ -#define X86_CR4_OSFXSR 0x0200 /* enable fast FPU save and restore */ -#define X86_CR4_OSXMMEXCPT 0x0400 /* enable unmasked SSE exceptions */ - /* * Save the cr4 feature set we're using (ie * Pentium 4MB enable and PPro Global page @@ -183,26 +168,6 @@ static inline void clear_in_cr4 (unsigned long mask) write_cr4(cr4); } -/* - * NSC/Cyrix CPU configuration register indexes - */ - -#define CX86_PCR0 0x20 -#define CX86_GCR 0xb8 -#define CX86_CCR0 0xc0 -#define CX86_CCR1 0xc1 -#define CX86_CCR2 0xc2 -#define CX86_CCR3 0xc3 -#define CX86_CCR4 0xe8 -#define CX86_CCR5 0xe9 -#define CX86_CCR6 0xea -#define CX86_CCR7 0xeb -#define CX86_PCR1 0xf0 -#define CX86_DIR0 0xfe -#define CX86_DIR1 0xff -#define CX86_ARR_BASE 0xc4 -#define CX86_RCR_BASE 0xdc - /* * NSC/Cyrix CPU indexed register access macros */ -- cgit v1.2.2 From a75c54f933bd8db9f4a609bd128663c179b3e6a1 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 2 May 2007 19:27:13 +0200 Subject: [PATCH] i386: i386 separate hardware-defined TSS from Linux additions On Thu, 2007-03-29 at 13:16 +0200, Andi Kleen wrote: > Please clean it up properly with two structs. Not sure about this, now I've done it. Running it here. If you like it, I can do x86-64 as well. == lguest defines its own TSS struct because the "struct tss_struct" contains linux-specific additions. Andi asked me to split the struct in processor.h. Unfortunately it makes usage a little awkward. Signed-off-by: Rusty Russell Signed-off-by: Andi Kleen --- include/asm-i386/processor.h | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) (limited to 'include/asm-i386/processor.h') diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h index 77e263267aa6..922260474646 100644 --- a/include/asm-i386/processor.h +++ b/include/asm-i386/processor.h @@ -291,7 +291,8 @@ typedef struct { struct thread_struct; -struct tss_struct { +/* This is the TSS defined by the hardware. */ +struct i386_hw_tss { unsigned short back_link,__blh; unsigned long esp0; unsigned short ss0,__ss0h; @@ -315,6 +316,11 @@ struct tss_struct { unsigned short gs, __gsh; unsigned short ldt, __ldth; unsigned short trace, io_bitmap_base; +} __attribute__((packed)); + +struct tss_struct { + struct i386_hw_tss x86_tss; + /* * The extra 1 is there because the CPU will access an * additional byte beyond the end of the IO permission @@ -381,10 +387,12 @@ struct thread_struct { * be within the limit. */ #define INIT_TSS { \ - .esp0 = sizeof(init_stack) + (long)&init_stack, \ - .ss0 = __KERNEL_DS, \ - .ss1 = __KERNEL_CS, \ - .io_bitmap_base = INVALID_IO_BITMAP_OFFSET, \ + .x86_tss = { \ + .esp0 = sizeof(init_stack) + (long)&init_stack, \ + .ss0 = __KERNEL_DS, \ + .ss1 = __KERNEL_CS, \ + .io_bitmap_base = INVALID_IO_BITMAP_OFFSET, \ + }, \ .io_bitmap = { [ 0 ... IO_BITMAP_LONGS] = ~0 }, \ } @@ -493,10 +501,10 @@ static inline void rep_nop(void) static inline void native_load_esp0(struct tss_struct *tss, struct thread_struct *thread) { - tss->esp0 = thread->esp0; + tss->x86_tss.esp0 = thread->esp0; /* This can only happen when SEP is enabled, no need to test "SEP"arately */ - if (unlikely(tss->ss1 != thread->sysenter_cs)) { - tss->ss1 = thread->sysenter_cs; + if (unlikely(tss->x86_tss.ss1 != thread->sysenter_cs)) { + tss->x86_tss.ss1 = thread->sysenter_cs; wrmsr(MSR_IA32_SYSENTER_CS, thread->sysenter_cs, 0); } } -- cgit v1.2.2 From 7c3576d261ce046789a7db14f43303f8120910c7 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 2 May 2007 19:27:16 +0200 Subject: [PATCH] i386: Convert PDA into the percpu section Currently x86 (similar to x84-64) has a special per-cpu structure called "i386_pda" which can be easily and efficiently referenced via the %fs register. An ELF section is more flexible than a structure, allowing any piece of code to use this area. Indeed, such a section already exists: the per-cpu area. So this patch: (1) Removes the PDA and uses per-cpu variables for each current member. (2) Replaces the __KERNEL_PDA segment with __KERNEL_PERCPU. (3) Creates a per-cpu mirror of __per_cpu_offset called this_cpu_off, which can be used to calculate addresses for this CPU's variables. (4) Simplifies startup, because %fs doesn't need to be loaded with a special segment at early boot; it can be deferred until the first percpu area is allocated (or never for UP). The result is less code and one less x86-specific concept. Signed-off-by: Rusty Russell Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Andi Kleen Cc: Andi Kleen --- include/asm-i386/processor.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/asm-i386/processor.h') diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h index 922260474646..ced2da8a0d65 100644 --- a/include/asm-i386/processor.h +++ b/include/asm-i386/processor.h @@ -377,7 +377,7 @@ struct thread_struct { .vm86_info = NULL, \ .sysenter_cs = __KERNEL_CS, \ .io_bitmap_ptr = NULL, \ - .fs = __KERNEL_PDA, \ + .fs = __KERNEL_PERCPU, \ } /* -- cgit v1.2.2 From c5413fbe894924ddb8aa474a4d4da52e7a6c7e0b Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 2 May 2007 19:27:16 +0200 Subject: [PATCH] i386: Fix UP gdt bugs Fixes two problems with the GDT when compiling for uniprocessor: - There's no percpu segment, so trying to load its selector into %fs fails. Use a null selector instead. - The real gdt needs to be loaded at some point. Do it in cpu_init(). Signed-off-by: Chris Wright Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Andi Kleen Cc: Rusty Russell --- include/asm-i386/processor.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/asm-i386/processor.h') diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h index ced2da8a0d65..70f3515c3db0 100644 --- a/include/asm-i386/processor.h +++ b/include/asm-i386/processor.h @@ -750,6 +750,7 @@ extern void enable_sep_cpu(void); extern int sysenter_setup(void); extern void cpu_set_gdt(int); +extern void switch_to_new_gdt(void); extern void cpu_init(void); extern int force_mwait; -- cgit v1.2.2