Commit 1e43c377 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'xtensa-20210329' of git://github.com/jcmvbkbc/linux-xtensa 

Pull xtensa fixes from Max Filippov:

 - fix build with separate exception vectors when they are placed too
   far from the rest of the kernel

 - fix uaccess-related livelock in do_page_fault.

* tag 'xtensa-20210329' of git://github.com/jcmvbkbc/linux-xtensa:
  xtensa: fix uaccess-related livelock in do_page_fault
  xtensa: move coprocessor_flush to the .text section
parents a5e13c6d 7b9acbb6

arch/xtensa/kernel/coprocessor.S

+33 −31
Original line number Diff line number Diff line
@@ -99,37 +99,6 @@ 
	LOAD_CP_REGS_TAB(6)

	LOAD_CP_REGS_TAB(7)



/*

 * coprocessor_flush(struct thread_info*, index)

 *                             a2        a3

 *

 * Save coprocessor registers for coprocessor 'index'.

 * The register values are saved to or loaded from the coprocessor area 

 * inside the task_info structure.

 *

 * Note that this function doesn't update the coprocessor_owner information!

 *

 */



ENTRY(coprocessor_flush)



	/* reserve 4 bytes on stack to save a0 */

	abi_entry(4)



	s32i	a0, a1, 0

	movi	a0, .Lsave_cp_regs_jump_table

	addx8	a3, a3, a0

	l32i	a4, a3, 4

	l32i	a3, a3, 0

	add	a2, a2, a4

	beqz	a3, 1f

	callx0	a3

1:	l32i	a0, a1, 0



	abi_ret(4)



ENDPROC(coprocessor_flush)



/*

 * Entry condition:

 *
@@ -245,6 +214,39 @@ ENTRY(fast_coprocessor) 


ENDPROC(fast_coprocessor)



	.text



/*

 * coprocessor_flush(struct thread_info*, index)

 *                             a2        a3

 *

 * Save coprocessor registers for coprocessor 'index'.

 * The register values are saved to or loaded from the coprocessor area

 * inside the task_info structure.

 *

 * Note that this function doesn't update the coprocessor_owner information!

 *

 */



ENTRY(coprocessor_flush)



	/* reserve 4 bytes on stack to save a0 */

	abi_entry(4)



	s32i	a0, a1, 0

	movi	a0, .Lsave_cp_regs_jump_table

	addx8	a3, a3, a0

	l32i	a4, a3, 4

	l32i	a3, a3, 0

	add	a2, a2, a4

	beqz	a3, 1f

	callx0	a3

1:	l32i	a0, a1, 0



	abi_ret(4)



ENDPROC(coprocessor_flush)



	.data



ENTRY(coprocessor_owner)

arch/xtensa/mm/fault.c

+4 −1
Original line number Diff line number Diff line
@@ -112,8 +112,11 @@ void do_page_fault(struct pt_regs *regs) 
	 */

	fault = handle_mm_fault(vma, address, flags, regs);



	if (fault_signal_pending(fault, regs))

	if (fault_signal_pending(fault, regs)) {

		if (!user_mode(regs))

			goto bad_page_fault;

		return;

	}



	if (unlikely(fault & VM_FAULT_ERROR)) {

		if (fault & VM_FAULT_OOM)