From fde0312d01b60a3fd5dc56e69a9613defbbc7097 Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Sun, 19 Jul 2009 00:09:56 +0900 Subject: x86: Remove unused patch_espfix_desc() patch_espfix_desc() is not used after commit dc4c2a0aed3b09f6e255bd5c3faa50fe6e0b2ded Signed-off-by: Akinobu Mita LKML-Reference: <20090718150955.GB11294@localhost.localdomain> Signed-off-by: Ingo Molnar --- arch/x86/include/asm/traps.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'arch/x86/include/asm') diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h index bfd74c032fca..4da91ad69e0d 100644 --- a/arch/x86/include/asm/traps.h +++ b/arch/x86/include/asm/traps.h @@ -81,9 +81,7 @@ extern int panic_on_unrecovered_nmi; void math_error(void __user *); void math_emulate(struct math_emu_info *); -#ifdef CONFIG_X86_32 -unsigned long patch_espfix_desc(unsigned long, unsigned long); -#else +#ifndef CONFIG_X86_32 asmlinkage void smp_thermal_interrupt(void); asmlinkage void mce_threshold_interrupt(void); #endif -- cgit From 57594742a2b545f8f114cda34f15650be8ae976d Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Sun, 19 Jul 2009 00:11:06 +0900 Subject: x86: Introduce set_desc_base() and set_desc_limit() Rename set_base()/set_limit to set_desc_base()/set_desc_limit() and rewrite them in C. These are naturally introduced by the idea of get_desc_base()/get_desc_limit(). The conversion actually found the bug in apm_32.c: bad_bios_desc is written at run-time, but it is defined const variable. Signed-off-by: Akinobu Mita LKML-Reference: <20090718151105.GC11294@localhost.localdomain> Signed-off-by: Ingo Molnar --- arch/x86/include/asm/desc.h | 13 +++++++++++++ arch/x86/include/asm/stackprotector.h | 4 +--- arch/x86/include/asm/system.h | 27 --------------------------- 3 files changed, 14 insertions(+), 30 deletions(-) (limited to 'arch/x86/include/asm') diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h index c993e9e0fed4..e8de2f6f5ca5 100644 --- a/arch/x86/include/asm/desc.h +++ b/arch/x86/include/asm/desc.h @@ -291,11 +291,24 @@ static inline unsigned long get_desc_base(const struct desc_struct *desc) return desc->base0 | ((desc->base1) << 16) | ((desc->base2) << 24); } +static inline void set_desc_base(struct desc_struct *desc, unsigned long base) +{ + desc->base0 = base & 0xffff; + desc->base1 = (base >> 16) & 0xff; + desc->base2 = (base >> 24) & 0xff; +} + static inline unsigned long get_desc_limit(const struct desc_struct *desc) { return desc->limit0 | (desc->limit << 16); } +static inline void set_desc_limit(struct desc_struct *desc, unsigned long limit) +{ + desc->limit0 = limit & 0xffff; + desc->limit = (limit >> 16) & 0xf; +} + static inline void _set_gate(int gate, unsigned type, void *addr, unsigned dpl, unsigned ist, unsigned seg) { diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h index c2d742c6e15f..cdc5e0b126a7 100644 --- a/arch/x86/include/asm/stackprotector.h +++ b/arch/x86/include/asm/stackprotector.h @@ -90,9 +90,7 @@ static inline void setup_stack_canary_segment(int cpu) struct desc_struct desc; desc = gdt_table[GDT_ENTRY_STACK_CANARY]; - desc.base0 = canary & 0xffff; - desc.base1 = (canary >> 16) & 0xff; - desc.base2 = (canary >> 24) & 0xff; + set_desc_base(&desc, canary); write_gdt_entry(gdt_table, GDT_ENTRY_STACK_CANARY, &desc, DESCTYPE_S); #endif } diff --git a/arch/x86/include/asm/system.h b/arch/x86/include/asm/system.h index 643c59b4bc6e..75c49c782e20 100644 --- a/arch/x86/include/asm/system.h +++ b/arch/x86/include/asm/system.h @@ -150,33 +150,6 @@ do { \ #endif #ifdef __KERNEL__ -#define _set_base(addr, base) do { unsigned long __pr; \ -__asm__ __volatile__ ("movw %%dx,%1\n\t" \ - "rorl $16,%%edx\n\t" \ - "movb %%dl,%2\n\t" \ - "movb %%dh,%3" \ - :"=&d" (__pr) \ - :"m" (*((addr)+2)), \ - "m" (*((addr)+4)), \ - "m" (*((addr)+7)), \ - "0" (base) \ - ); } while (0) - -#define _set_limit(addr, limit) do { unsigned long __lr; \ -__asm__ __volatile__ ("movw %%dx,%1\n\t" \ - "rorl $16,%%edx\n\t" \ - "movb %2,%%dh\n\t" \ - "andb $0xf0,%%dh\n\t" \ - "orb %%dh,%%dl\n\t" \ - "movb %%dl,%2" \ - :"=&d" (__lr) \ - :"m" (*(addr)), \ - "m" (*((addr)+6)), \ - "0" (limit) \ - ); } while (0) - -#define set_base(ldt, base) _set_base(((char *)&(ldt)) , (base)) -#define set_limit(ldt, limit) _set_limit(((char *)&(ldt)) , ((limit)-1)) extern void native_load_gs_index(unsigned); -- cgit From 1e5de18278e6862f4198412b5059a03770fa816a Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Sun, 19 Jul 2009 00:12:20 +0900 Subject: x86: Introduce GDT_ENTRY_INIT() GDT_ENTRY_INIT is static initializer of desc_struct. We already have similar macro GDT_ENTRY() but it's static initializer for u64 and it cannot be used for desc_struct. Signed-off-by: Akinobu Mita LKML-Reference: <20090718151219.GD11294@localhost.localdomain> Signed-off-by: Ingo Molnar --- arch/x86/include/asm/desc_defs.h | 6 ++++++ arch/x86/include/asm/lguest.h | 5 +++-- arch/x86/include/asm/stackprotector.h | 2 +- 3 files changed, 10 insertions(+), 3 deletions(-) (limited to 'arch/x86/include/asm') diff --git a/arch/x86/include/asm/desc_defs.h b/arch/x86/include/asm/desc_defs.h index a6adefa28b94..9d6684849fd9 100644 --- a/arch/x86/include/asm/desc_defs.h +++ b/arch/x86/include/asm/desc_defs.h @@ -34,6 +34,12 @@ struct desc_struct { }; } __attribute__((packed)); +#define GDT_ENTRY_INIT(flags, base, limit) { { { \ + .a = ((limit) & 0xffff) | (((base) & 0xffff) << 16), \ + .b = (((base) & 0xff0000) >> 16) | (((flags) & 0xf0ff) << 8) | \ + ((limit) & 0xf0000) | ((base) & 0xff000000), \ + } } } + enum { GATE_INTERRUPT = 0xE, GATE_TRAP = 0xF, diff --git a/arch/x86/include/asm/lguest.h b/arch/x86/include/asm/lguest.h index 313389cd50d2..94cd69858b14 100644 --- a/arch/x86/include/asm/lguest.h +++ b/arch/x86/include/asm/lguest.h @@ -91,8 +91,9 @@ static inline void lguest_set_ts(void) } /* Full 4G segment descriptors, suitable for CS and DS. */ -#define FULL_EXEC_SEGMENT ((struct desc_struct){ { {0x0000ffff, 0x00cf9b00} } }) -#define FULL_SEGMENT ((struct desc_struct){ { {0x0000ffff, 0x00cf9300} } }) +#define FULL_EXEC_SEGMENT \ + ((struct desc_struct)GDT_ENTRY_INIT(0xc09b, 0, 0xfffff)) +#define FULL_SEGMENT ((struct desc_struct)GDT_ENTRY_INIT(0xc093, 0, 0xfffff)) #endif /* __ASSEMBLY__ */ diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h index cdc5e0b126a7..44efdff3975d 100644 --- a/arch/x86/include/asm/stackprotector.h +++ b/arch/x86/include/asm/stackprotector.h @@ -48,7 +48,7 @@ * head_32 for boot CPU and setup_per_cpu_areas() for others. */ #define GDT_STACK_CANARY_INIT \ - [GDT_ENTRY_STACK_CANARY] = { { { 0x00000018, 0x00409000 } } }, + [GDT_ENTRY_STACK_CANARY] = GDT_ENTRY_INIT(0x4090, 0, 0x18), /* * Initialize the stackprotector canary value. -- cgit From 8b5a10fc6fd02289ea03480f93382b1a99006142 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Wed, 19 Aug 2009 08:40:48 +0100 Subject: x86: properly annotate alternatives.c Some of the NOPs tables aren't used on 64-bits, quite some code and data is needed post-init for module loading only, and a couple of functions aren't used outside that file (i.e. can be static, and don't need to be exported). The change to __INITDATA/__INITRODATA is needed to avoid an assembler warning. Signed-off-by: Jan Beulich LKML-Reference: <4A8BC8A00200007800010823@vpn.id2.novell.com> Acked-by: Sam Ravnborg Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/alternative.h | 7 ------- 1 file changed, 7 deletions(-) (limited to 'arch/x86/include/asm') diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index 1a37bcdc8606..c240efc74e00 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -73,8 +73,6 @@ static inline void alternatives_smp_module_del(struct module *mod) {} static inline void alternatives_smp_switch(int smp) {} #endif /* CONFIG_SMP */ -const unsigned char *const *find_nop_table(void); - /* alternative assembly primitive: */ #define ALTERNATIVE(oldinstr, newinstr, feature) \ \ @@ -144,8 +142,6 @@ static inline void apply_paravirt(struct paravirt_patch_site *start, #define __parainstructions_end NULL #endif -extern void add_nops(void *insns, unsigned int len); - /* * Clear and restore the kernel write-protection flag on the local CPU. * Allows the kernel to edit read-only pages. @@ -161,10 +157,7 @@ extern void add_nops(void *insns, unsigned int len); * Intel's errata. * On the local CPU you need to be protected again NMI or MCE handlers seeing an * inconsistent instruction while you patch. - * The _early version expects the memory to already be RW. */ - extern void *text_poke(void *addr, const void *opcode, size_t len); -extern void *text_poke_early(void *addr, const void *opcode, size_t len); #endif /* _ASM_X86_ALTERNATIVE_H */ -- cgit From ab94fcf528d127fcb490175512a8910f37e5b346 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Tue, 25 Aug 2009 16:47:16 -0700 Subject: x86: allow "=rm" in native_save_fl() This is a partial revert of f1f029c7bfbf4ee1918b90a431ab823bed812504. "=rm" is allowed in this context, because "pop" is explicitly defined to adjust the stack pointer *before* it evaluates its effective address, if it has one. Thus, we do end up writing to the correct address even if we use an on-stack memory argument. The original reporter for f1f029c7bfbf4ee1918b90a431ab823bed812504 was apparently using a broken x86 simulator. [ Impact: performance ] Signed-off-by: H. Peter Anvin Cc: Gabe Black --- arch/x86/include/asm/irqflags.h | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'arch/x86/include/asm') diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h index c6ccbe7e81ad..9e2b952f810a 100644 --- a/arch/x86/include/asm/irqflags.h +++ b/arch/x86/include/asm/irqflags.h @@ -13,14 +13,13 @@ static inline unsigned long native_save_fl(void) unsigned long flags; /* - * Note: this needs to be "=r" not "=rm", because we have the - * stack offset from what gcc expects at the time the "pop" is - * executed, and so a memory reference with respect to the stack - * would end up using the wrong address. + * "=rm" is safe here, because "pop" adjusts the stack before + * it evaluates its effective address -- this is part of the + * documented behavior of the "pop" instruction. */ asm volatile("# __raw_save_flags\n\t" "pushf ; pop %0" - : "=r" (flags) + : "=rm" (flags) : /* no input */ : "memory"); -- cgit From 1ea0d14e480c245683927eecc03a70faf06e80c8 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Thu, 3 Sep 2009 12:27:15 -0700 Subject: x86/i386: Make sure stack-protector segment base is cache aligned The Intel Optimization Reference Guide says: In Intel Atom microarchitecture, the address generation unit assumes that the segment base will be 0 by default. Non-zero segment base will cause load and store operations to experience a delay. - If the segment base isn't aligned to a cache line boundary, the max throughput of memory operations is reduced to one [e]very 9 cycles. [...] Assembly/Compiler Coding Rule 15. (H impact, ML generality) For Intel Atom processors, use segments with base set to 0 whenever possible; avoid non-zero segment base address that is not aligned to cache line boundary at all cost. We can't avoid having a non-zero base for the stack-protector segment, but we can make it cache-aligned. Signed-off-by: Jeremy Fitzhardinge Cc: LKML-Reference: <4AA01893.6000507@goop.org> Signed-off-by: Ingo Molnar --- arch/x86/include/asm/processor.h | 12 +++++++++++- arch/x86/include/asm/stackprotector.h | 4 ++-- arch/x86/include/asm/system.h | 2 +- 3 files changed, 14 insertions(+), 4 deletions(-) (limited to 'arch/x86/include/asm') diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index c7768269b1cf..e597ecc8753c 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -403,7 +403,17 @@ extern unsigned long kernel_eflags; extern asmlinkage void ignore_sysret(void); #else /* X86_64 */ #ifdef CONFIG_CC_STACKPROTECTOR -DECLARE_PER_CPU(unsigned long, stack_canary); +/* + * Make sure stack canary segment base is cached-aligned: + * "For Intel Atom processors, avoid non zero segment base address + * that is not aligned to cache line boundary at all cost." + * (Optim Ref Manual Assembly/Compiler Coding Rule 15.) + */ +struct stack_canary { + char __pad[20]; /* canary at %gs:20 */ + unsigned long canary; +}; +DECLARE_PER_CPU(struct stack_canary, stack_canary) ____cacheline_aligned; #endif #endif /* X86_64 */ diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h index 44efdff3975d..157517763565 100644 --- a/arch/x86/include/asm/stackprotector.h +++ b/arch/x86/include/asm/stackprotector.h @@ -78,14 +78,14 @@ static __always_inline void boot_init_stack_canary(void) #ifdef CONFIG_X86_64 percpu_write(irq_stack_union.stack_canary, canary); #else - percpu_write(stack_canary, canary); + percpu_write(stack_canary.canary, canary); #endif } static inline void setup_stack_canary_segment(int cpu) { #ifdef CONFIG_X86_32 - unsigned long canary = (unsigned long)&per_cpu(stack_canary, cpu) - 20; + unsigned long canary = (unsigned long)&per_cpu(stack_canary, cpu); struct desc_struct *gdt_table = get_cpu_gdt_table(cpu); struct desc_struct desc; diff --git a/arch/x86/include/asm/system.h b/arch/x86/include/asm/system.h index 75c49c782e20..f08f97374892 100644 --- a/arch/x86/include/asm/system.h +++ b/arch/x86/include/asm/system.h @@ -31,7 +31,7 @@ void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p, "movl %P[task_canary](%[next]), %%ebx\n\t" \ "movl %%ebx, "__percpu_arg([stack_canary])"\n\t" #define __switch_canary_oparam \ - , [stack_canary] "=m" (per_cpu_var(stack_canary)) + , [stack_canary] "=m" (per_cpu_var(stack_canary.canary)) #define __switch_canary_iparam \ , [task_canary] "i" (offsetof(struct task_struct, stack_canary)) #else /* CC_STACKPROTECTOR */ -- cgit From 53f824520b6d84ca5b4a8fd71addc91dbf64357e Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Thu, 3 Sep 2009 14:31:44 -0700 Subject: x86/i386: Put aligned stack-canary in percpu shared_aligned section Pack aligned things together into a special section to minimize padding holes. Suggested-by: Eric Dumazet Signed-off-by: Jeremy Fitzhardinge Cc: Tejun Heo LKML-Reference: <4AA035C0.9070202@goop.org> [ queued up in tip:x86/asm because it depends on this commit: x86/i386: Make sure stack-protector segment base is cache aligned ] Signed-off-by: Ingo Molnar --- arch/x86/include/asm/processor.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/include/asm') diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index e597ecc8753c..ac7e79654f3a 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -413,7 +413,7 @@ struct stack_canary { char __pad[20]; /* canary at %gs:20 */ unsigned long canary; }; -DECLARE_PER_CPU(struct stack_canary, stack_canary) ____cacheline_aligned; +DECLARE_PER_CPU_ALIGNED(struct stack_canary, stack_canary); #endif #endif /* X86_64 */ -- cgit