redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

x86/entry: Rename SYSENTER_stack to CPU_ENTRY_AREA_entry_stack 

If the kernel oopses while on the trampoline stack, it will print
"<SYSENTER>" even if SYSENTER is not involved.  That is rather confusing.

The "SYSENTER" stack is used for a lot more than SYSENTER now.  Give it a
better string to display in stack dumps, and rename the kernel code to
match.

Also move the 32-bit code over to the new naming even though it still uses
the entry stack only for SYSENTER.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
hifive-unleashed-5.1
Dave Hansen 2017-12-04 17:25:07 -08:00 committed by Ingo Molnar
parent e8ffe96e59
commit 4fe2d8b11a
11 changed files with 44 additions and 38 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
arch/x86/entry/entry_32.S
View File

@ -942,9 +942,9 @@ ENTRY(debug)
/* Are we currently on the SYSENTER stack? */
movl PER_CPU_VAR(cpu_entry_area), %ecx
addl $CPU_ENTRY_AREA_SYSENTER_stack + SIZEOF_SYSENTER_stack, %ecx
subl %eax, %ecx /* ecx = (end of SYSENTER_stack) - esp */
cmpl $SIZEOF_SYSENTER_stack, %ecx
addl $CPU_ENTRY_AREA_entry_stack + SIZEOF_entry_stack, %ecx
subl %eax, %ecx /* ecx = (end of entry_stack) - esp */
cmpl $SIZEOF_entry_stack, %ecx
jb .Ldebug_from_sysenter_stack
TRACE_IRQS_OFF
@ -986,9 +986,9 @@ ENTRY(nmi)
/* Are we currently on the SYSENTER stack? */
movl PER_CPU_VAR(cpu_entry_area), %ecx
addl $CPU_ENTRY_AREA_SYSENTER_stack + SIZEOF_SYSENTER_stack, %ecx
subl %eax, %ecx /* ecx = (end of SYSENTER_stack) - esp */
cmpl $SIZEOF_SYSENTER_stack, %ecx
addl $CPU_ENTRY_AREA_entry_stack + SIZEOF_entry_stack, %ecx
subl %eax, %ecx /* ecx = (end of entry_stack) - esp */
cmpl $SIZEOF_entry_stack, %ecx
jb .Lnmi_from_sysenter_stack
/* Not on SYSENTER stack. */

4
arch/x86/entry/entry_64.S
View File

@ -154,8 +154,8 @@ END(native_usergs_sysret64)
_entry_trampoline - CPU_ENTRY_AREA_entry_trampoline(%rip)
/* The top word of the SYSENTER stack is hot and is usable as scratch space. */
#define RSP_SCRATCH CPU_ENTRY_AREA_SYSENTER_stack + \
SIZEOF_SYSENTER_stack - 8 + CPU_ENTRY_AREA
#define RSP_SCRATCH CPU_ENTRY_AREA_entry_stack + \
SIZEOF_entry_stack - 8 + CPU_ENTRY_AREA
ENTRY(entry_SYSCALL_64_trampoline)
UNWIND_HINT_EMPTY

8
arch/x86/include/asm/fixmap.h
View File

@ -56,10 +56,10 @@ struct cpu_entry_area {
char gdt[PAGE_SIZE];
/*
* The GDT is just below SYSENTER_stack and thus serves (on x86_64) as
* The GDT is just below entry_stack and thus serves (on x86_64) as
* a a read-only guard page.
*/
struct SYSENTER_stack_page SYSENTER_stack_page;
struct entry_stack_page entry_stack_page;
/*
* On x86_64, the TSS is mapped RO. On x86_32, it's mapped RW because
@ -250,9 +250,9 @@ static inline struct cpu_entry_area *get_cpu_entry_area(int cpu)
return (struct cpu_entry_area *)__fix_to_virt(__get_cpu_entry_area_page_index(cpu, 0));
}
static inline struct SYSENTER_stack *cpu_SYSENTER_stack(int cpu)
static inline struct entry_stack *cpu_entry_stack(int cpu)
{
return &get_cpu_entry_area(cpu)->SYSENTER_stack_page.stack;
return &get_cpu_entry_area(cpu)->entry_stack_page.stack;
}
#endif /* !__ASSEMBLY__ */

6
arch/x86/include/asm/processor.h
View File

@ -336,12 +336,12 @@ struct x86_hw_tss {
#define IO_BITMAP_OFFSET (offsetof(struct tss_struct, io_bitmap) - offsetof(struct tss_struct, x86_tss))
#define INVALID_IO_BITMAP_OFFSET 0x8000
struct SYSENTER_stack {
struct entry_stack {
unsigned long words[64];
};
struct SYSENTER_stack_page {
struct SYSENTER_stack stack;
struct entry_stack_page {
struct entry_stack stack;
} __aligned(PAGE_SIZE);
struct tss_struct {

4
arch/x86/include/asm/stacktrace.h
View File

@ -16,7 +16,7 @@ enum stack_type {
STACK_TYPE_TASK,
STACK_TYPE_IRQ,
STACK_TYPE_SOFTIRQ,
STACK_TYPE_SYSENTER,
STACK_TYPE_ENTRY,
STACK_TYPE_EXCEPTION,
STACK_TYPE_EXCEPTION_LAST = STACK_TYPE_EXCEPTION + N_EXCEPTION_STACKS-1,
};
@ -29,7 +29,7 @@ struct stack_info {
bool in_task_stack(unsigned long *stack, struct task_struct *task,
struct stack_info *info);
bool in_sysenter_stack(unsigned long *stack, struct stack_info *info);
bool in_entry_stack(unsigned long *stack, struct stack_info *info);
int get_stack_info(unsigned long *stack, struct task_struct *task,
struct stack_info *info, unsigned long *visit_mask);

4
arch/x86/kernel/asm-offsets.c
View File

@ -97,6 +97,6 @@ void common(void) {
/* Layout info for cpu_entry_area */
OFFSET(CPU_ENTRY_AREA_tss, cpu_entry_area, tss);
OFFSET(CPU_ENTRY_AREA_entry_trampoline, cpu_entry_area, entry_trampoline);
OFFSET(CPU_ENTRY_AREA_SYSENTER_stack, cpu_entry_area, SYSENTER_stack_page);
DEFINE(SIZEOF_SYSENTER_stack, sizeof(struct SYSENTER_stack));
OFFSET(CPU_ENTRY_AREA_entry_stack, cpu_entry_area, entry_stack_page);
DEFINE(SIZEOF_entry_stack, sizeof(struct entry_stack));
}

2
arch/x86/kernel/asm-offsets_32.c
View File

@ -48,7 +48,7 @@ void foo(void)
/* Offset from the sysenter stack to tss.sp0 */
DEFINE(TSS_sysenter_sp0, offsetof(struct cpu_entry_area, tss.x86_tss.sp0) -
offsetofend(struct cpu_entry_area, SYSENTER_stack_page.stack));
offsetofend(struct cpu_entry_area, entry_stack_page.stack));
#ifdef CONFIG_CC_STACKPROTECTOR
BLANK();

14
arch/x86/kernel/cpu/common.c
View File

@ -487,8 +487,8 @@ static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ]);
#endif
static DEFINE_PER_CPU_PAGE_ALIGNED(struct SYSENTER_stack_page,
SYSENTER_stack_storage);
static DEFINE_PER_CPU_PAGE_ALIGNED(struct entry_stack_page,
entry_stack_storage);
static void __init
set_percpu_fixmap_pages(int idx, void *ptr, int pages, pgprot_t prot)
@ -523,8 +523,8 @@ static void __init setup_cpu_entry_area(int cpu)
#endif
__set_fixmap(get_cpu_entry_area_index(cpu, gdt), get_cpu_gdt_paddr(cpu), gdt_prot);
set_percpu_fixmap_pages(get_cpu_entry_area_index(cpu, SYSENTER_stack_page),
per_cpu_ptr(&SYSENTER_stack_storage, cpu), 1,
set_percpu_fixmap_pages(get_cpu_entry_area_index(cpu, entry_stack_page),
per_cpu_ptr(&entry_stack_storage, cpu), 1,
PAGE_KERNEL);
/*
@ -1323,7 +1323,7 @@ void enable_sep_cpu(void)
tss->x86_tss.ss1 = __KERNEL_CS;
wrmsr(MSR_IA32_SYSENTER_CS, tss->x86_tss.ss1, 0);
wrmsr(MSR_IA32_SYSENTER_ESP, (unsigned long)(cpu_SYSENTER_stack(cpu) + 1), 0);
wrmsr(MSR_IA32_SYSENTER_ESP, (unsigned long)(cpu_entry_stack(cpu) + 1), 0);
wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long)entry_SYSENTER_32, 0);
put_cpu();
@ -1440,7 +1440,7 @@ void syscall_init(void)
* AMD doesn't allow SYSENTER in long mode (either 32- or 64-bit).
*/
wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS);
wrmsrl_safe(MSR_IA32_SYSENTER_ESP, (unsigned long)(cpu_SYSENTER_stack(cpu) + 1));
wrmsrl_safe(MSR_IA32_SYSENTER_ESP, (unsigned long)(cpu_entry_stack(cpu) + 1));
wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)entry_SYSENTER_compat);
#else
wrmsrl(MSR_CSTAR, (unsigned long)ignore_sysret);
@ -1655,7 +1655,7 @@ void cpu_init(void)
*/
set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss);
load_TR_desc();
load_sp0((unsigned long)(cpu_SYSENTER_stack(cpu) + 1));
load_sp0((unsigned long)(cpu_entry_stack(cpu) + 1));
load_mm_ldt(&init_mm);

10
arch/x86/kernel/dumpstack.c
View File

@ -43,9 +43,9 @@ bool in_task_stack(unsigned long *stack, struct task_struct *task,
return true;
}
bool in_sysenter_stack(unsigned long *stack, struct stack_info *info)
bool in_entry_stack(unsigned long *stack, struct stack_info *info)
{
struct SYSENTER_stack *ss = cpu_SYSENTER_stack(smp_processor_id());
struct entry_stack *ss = cpu_entry_stack(smp_processor_id());
void *begin = ss;
void *end = ss + 1;
@ -53,7 +53,7 @@ bool in_sysenter_stack(unsigned long *stack, struct stack_info *info)
if ((void *)stack < begin || (void *)stack >= end)
return false;
info->type = STACK_TYPE_SYSENTER;
info->type = STACK_TYPE_ENTRY;
info->begin = begin;
info->end = end;
info->next_sp = NULL;
@ -111,13 +111,13 @@ void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
* - task stack
* - interrupt stack
* - HW exception stacks (double fault, nmi, debug, mce)
* - SYSENTER stack
* - entry stack
*
* x86-32 can have up to four stacks:
* - task stack
* - softirq stack
* - hardirq stack
* - SYSENTER stack
* - entry stack
*/
for (regs = NULL; stack; stack = PTR_ALIGN(stack_info.next_sp, sizeof(long))) {
const char *stack_name;

6
arch/x86/kernel/dumpstack_32.c
View File

@ -26,8 +26,8 @@ const char *stack_type_name(enum stack_type type)
if (type == STACK_TYPE_SOFTIRQ)
return "SOFTIRQ";
if (type == STACK_TYPE_SYSENTER)
return "SYSENTER";
if (type == STACK_TYPE_ENTRY)
return "ENTRY_TRAMPOLINE";
return NULL;
}
@ -96,7 +96,7 @@ int get_stack_info(unsigned long *stack, struct task_struct *task,
if (task != current)
goto unknown;
if (in_sysenter_stack(stack, info))
if (in_entry_stack(stack, info))
goto recursion_check;
if (in_hardirq_stack(stack, info))

12
arch/x86/kernel/dumpstack_64.c
View File

@ -37,8 +37,14 @@ const char *stack_type_name(enum stack_type type)
if (type == STACK_TYPE_IRQ)
return "IRQ";
if (type == STACK_TYPE_SYSENTER)
return "SYSENTER";
if (type == STACK_TYPE_ENTRY) {
/*
* On 64-bit, we have a generic entry stack that we
* use for all the kernel entry points, including
* SYSENTER.
*/
return "ENTRY_TRAMPOLINE";
}
if (type >= STACK_TYPE_EXCEPTION && type <= STACK_TYPE_EXCEPTION_LAST)
return exception_stack_names[type - STACK_TYPE_EXCEPTION];
@ -118,7 +124,7 @@ int get_stack_info(unsigned long *stack, struct task_struct *task,
if (in_irq_stack(stack, info))
goto recursion_check;
if (in_sysenter_stack(stack, info))
if (in_entry_stack(stack, info))
goto recursion_check;
goto unknown;