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Commit 95648c0e authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull x86 fixes from Peter Anvin:
 "A small collection of minor fixes.  The FPU stuff is still pending, I
  fear.  I haven't heard anything from Suresh so I suspect I'm going to
  have to dig into the init specifics myself and fix up the patchset"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Ignore NMIs that come in during early boot
  x86, trace: Further robustify CR2 handling vs tracing
  x86, trace: Fix CR2 corruption when tracing page faults
  x86/efi: Quirk out SGI UV
parents 9579f10d 5fa10196

arch/x86/include/asm/efi.h

+1 −0
Original line number Diff line number Diff line
@@ -134,6 +134,7 @@ extern void efi_setup_page_tables(void); 
extern void __init old_map_region(efi_memory_desc_t *md);

extern void __init runtime_code_page_mkexec(void);

extern void __init efi_runtime_mkexec(void);

extern void __init efi_apply_memmap_quirks(void);



struct efi_setup_data {

	u64 fw_vendor;

arch/x86/kernel/head_32.S

+6 −1
Original line number Diff line number Diff line
@@ -544,6 +544,10 @@ ENDPROC(early_idt_handlers) 
	/* This is global to keep gas from relaxing the jumps */

ENTRY(early_idt_handler)

	cld



	cmpl $X86_TRAP_NMI,(%esp)

	je is_nmi		# Ignore NMI



	cmpl $2,%ss:early_recursion_flag

	je hlt_loop

	incl %ss:early_recursion_flag
@@ -594,8 +598,9 @@ ex_entry: 
	pop %edx

	pop %ecx

	pop %eax

	addl $8,%esp		/* drop vector number and error code */

	decl %ss:early_recursion_flag

is_nmi:

	addl $8,%esp		/* drop vector number and error code */

	iret

ENDPROC(early_idt_handler)

arch/x86/kernel/head_64.S

+5 −1
Original line number Diff line number Diff line
@@ -343,6 +343,9 @@ early_idt_handlers: 
ENTRY(early_idt_handler)

	cld



	cmpl $X86_TRAP_NMI,(%rsp)

	je is_nmi		# Ignore NMI



	cmpl $2,early_recursion_flag(%rip)

	jz  1f

	incl early_recursion_flag(%rip)
@@ -405,8 +408,9 @@ ENTRY(early_idt_handler) 
	popq %rdx

	popq %rcx

	popq %rax

	addq $16,%rsp		# drop vector number and error code

	decl early_recursion_flag(%rip)

is_nmi:

	addq $16,%rsp		# drop vector number and error code

	INTERRUPT_RETURN

ENDPROC(early_idt_handler)

arch/x86/kernel/setup.c

+2 −8
Original line number Diff line number Diff line
@@ -1239,14 +1239,8 @@ void __init setup_arch(char **cmdline_p) 
	register_refined_jiffies(CLOCK_TICK_RATE);



#ifdef CONFIG_EFI

	/* Once setup is done above, unmap the EFI memory map on

	 * mismatched firmware/kernel archtectures since there is no

	 * support for runtime services.

	 */

	if (efi_enabled(EFI_BOOT) && !efi_is_native()) {

		pr_info("efi: Setup done, disabling due to 32/64-bit mismatch\n");

		efi_unmap_memmap();

	}

	if (efi_enabled(EFI_BOOT))

		efi_apply_memmap_quirks();

#endif

}

arch/x86/mm/fault.c

+33 −14
Original line number Diff line number Diff line
@@ -1020,13 +1020,17 @@ static inline bool smap_violation(int error_code, struct pt_regs *regs) 
 * This routine handles page faults.  It determines the address,

 * and the problem, and then passes it off to one of the appropriate

 * routines.

 *

 * This function must have noinline because both callers

 * {,trace_}do_page_fault() have notrace on. Having this an actual function

 * guarantees there's a function trace entry.

 */

static void __kprobes

__do_page_fault(struct pt_regs *regs, unsigned long error_code)

static void __kprobes noinline

__do_page_fault(struct pt_regs *regs, unsigned long error_code,

		unsigned long address)

{

	struct vm_area_struct *vma;

	struct task_struct *tsk;

	unsigned long address;

	struct mm_struct *mm;

	int fault;

	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
@@ -1034,9 +1038,6 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code) 
	tsk = current;

	mm = tsk->mm;



	/* Get the faulting address: */

	address = read_cr2();



	/*

	 * Detect and handle instructions that would cause a page fault for

	 * both a tracked kernel page and a userspace page.
@@ -1248,32 +1249,50 @@ good_area: 
	up_read(&mm->mmap_sem);

}



dotraplinkage void __kprobes

dotraplinkage void __kprobes notrace

do_page_fault(struct pt_regs *regs, unsigned long error_code)

{

	unsigned long address = read_cr2(); /* Get the faulting address */

	enum ctx_state prev_state;



	/*

	 * We must have this function tagged with __kprobes, notrace and call

	 * read_cr2() before calling anything else. To avoid calling any kind

	 * of tracing machinery before we've observed the CR2 value.

	 *

	 * exception_{enter,exit}() contain all sorts of tracepoints.

	 */



	prev_state = exception_enter();

	__do_page_fault(regs, error_code);

	__do_page_fault(regs, error_code, address);

	exception_exit(prev_state);

}



static void trace_page_fault_entries(struct pt_regs *regs,

#ifdef CONFIG_TRACING

static void trace_page_fault_entries(unsigned long address, struct pt_regs *regs,

				     unsigned long error_code)

{

	if (user_mode(regs))

		trace_page_fault_user(read_cr2(), regs, error_code);

		trace_page_fault_user(address, regs, error_code);

	else

		trace_page_fault_kernel(read_cr2(), regs, error_code);

		trace_page_fault_kernel(address, regs, error_code);

}



dotraplinkage void __kprobes

dotraplinkage void __kprobes notrace

trace_do_page_fault(struct pt_regs *regs, unsigned long error_code)

{

	/*

	 * The exception_enter and tracepoint processing could

	 * trigger another page faults (user space callchain

	 * reading) and destroy the original cr2 value, so read

	 * the faulting address now.

	 */

	unsigned long address = read_cr2();

	enum ctx_state prev_state;



	prev_state = exception_enter();

	trace_page_fault_entries(regs, error_code);

	__do_page_fault(regs, error_code);

	trace_page_fault_entries(address, regs, error_code);

	__do_page_fault(regs, error_code, address);

	exception_exit(prev_state);

}

#endif /* CONFIG_TRACING */