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Diffstat (limited to 'arch/x86/kernel/doublefault_32.c')
-rw-r--r--arch/x86/kernel/doublefault_32.c18
1 files changed, 5 insertions, 13 deletions
diff --git a/arch/x86/kernel/doublefault_32.c b/arch/x86/kernel/doublefault_32.c
index 3793646f0fb5..3b58d8703094 100644
--- a/arch/x86/kernel/doublefault_32.c
+++ b/arch/x86/kernel/doublefault_32.c
@@ -6,12 +6,10 @@
#include <linux/fs.h>
#include <linux/uaccess.h>
-#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/desc.h>
#include <asm/traps.h>
-extern void double_fault(void);
#define ptr_ok(x) ((x) > PAGE_OFFSET && (x) < PAGE_OFFSET + MAXMEM)
#define TSS(x) this_cpu_read(cpu_tss_rw.x86_tss.x)
@@ -22,7 +20,7 @@ static void set_df_gdt_entry(unsigned int cpu);
* Called by double_fault with CR0.TS and EFLAGS.NT cleared. The CPU thinks
* we're running the doublefault task. Cannot return.
*/
-asmlinkage notrace void __noreturn doublefault_shim(void)
+asmlinkage noinstr void __noreturn doublefault_shim(void)
{
unsigned long cr2;
struct pt_regs regs;
@@ -41,7 +39,7 @@ asmlinkage notrace void __noreturn doublefault_shim(void)
* Fill in pt_regs. A downside of doing this in C is that the unwinder
* won't see it (no ENCODE_FRAME_POINTER), so a nested stack dump
* won't successfully unwind to the source of the double fault.
- * The main dump from do_double_fault() is fine, though, since it
+ * The main dump from exc_double_fault() is fine, though, since it
* uses these regs directly.
*
* If anyone ever cares, this could be moved to asm.
@@ -71,7 +69,7 @@ asmlinkage notrace void __noreturn doublefault_shim(void)
regs.cx = TSS(cx);
regs.bx = TSS(bx);
- do_double_fault(&regs, 0, cr2);
+ exc_double_fault(&regs, 0, cr2);
/*
* x86_32 does not save the original CR3 anywhere on a task switch.
@@ -79,13 +77,9 @@ asmlinkage notrace void __noreturn doublefault_shim(void)
* some way to reconstruct CR3. We could make a credible guess based
* on cpu_tlbstate, but that would be racy and would not account for
* PTI.
- *
- * Instead, don't bother. We can return through
- * rewind_stack_do_exit() instead.
*/
panic("cannot return from double fault\n");
}
-NOKPROBE_SYMBOL(doublefault_shim);
DEFINE_PER_CPU_PAGE_ALIGNED(struct doublefault_stack, doublefault_stack) = {
.tss = {
@@ -96,16 +90,14 @@ DEFINE_PER_CPU_PAGE_ALIGNED(struct doublefault_stack, doublefault_stack) = {
.ldt = 0,
.io_bitmap_base = IO_BITMAP_OFFSET_INVALID,
- .ip = (unsigned long) double_fault,
+ .ip = (unsigned long) asm_exc_double_fault,
.flags = X86_EFLAGS_FIXED,
.es = __USER_DS,
.cs = __KERNEL_CS,
.ss = __KERNEL_DS,
.ds = __USER_DS,
.fs = __KERNEL_PERCPU,
-#ifndef CONFIG_X86_32_LAZY_GS
- .gs = __KERNEL_STACK_CANARY,
-#endif
+ .gs = 0,
.__cr3 = __pa_nodebug(swapper_pg_dir),
},