Commit e9016174 authored by Kefeng Wang's avatar Kefeng Wang Committed by Andrew Morton
Browse files

arm: mm: drop VM_FAULT_BADMAP/VM_FAULT_BADACCESS 

If bad map or access, directly set code to SEGV_MAPRR or SEGV_ACCERR, also
set fault to 0 and goto error handling, which make us to drop the arch's
special vm fault reason.

[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/20240411130925.73281-3-wangkefeng.wang@huawei.com


Signed-off-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Cc: Aishwarya TCV <aishwarya.tcv@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Cristian Marussi <cristian.marussi@arm.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent eebb5181

arch/arm/mm/fault.c

+15 −15
Original line number Diff line number Diff line
@@ -226,9 +226,6 @@ void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs) 
}



#ifdef CONFIG_MMU

#define VM_FAULT_BADMAP		((__force vm_fault_t)0x010000)

#define VM_FAULT_BADACCESS	((__force vm_fault_t)0x020000)



static inline bool is_permission_fault(unsigned int fsr)

{

	int fs = fsr_fs(fsr);
@@ -295,7 +292,8 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) 
	if (!(vma->vm_flags & vm_flags)) {

		vma_end_read(vma);

		count_vm_vma_lock_event(VMA_LOCK_SUCCESS);

		fault = VM_FAULT_BADACCESS;

		fault = 0;

		code = SEGV_ACCERR;

		goto bad_area;

	}

	fault = handle_mm_fault(vma, addr, flags | FAULT_FLAG_VMA_LOCK, regs);
@@ -321,7 +319,8 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) 
retry:

	vma = lock_mm_and_find_vma(mm, addr, regs);

	if (unlikely(!vma)) {

		fault = VM_FAULT_BADMAP;

		fault = 0;

		code = SEGV_MAPERR;

		goto bad_area;

	}
@@ -329,9 +328,13 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) 
	 * ok, we have a good vm_area for this memory access, check the

	 * permissions on the VMA allow for the fault which occurred.

	 */

	if (!(vma->vm_flags & vm_flags))

		fault = VM_FAULT_BADACCESS;

	else

	if (!(vma->vm_flags & vm_flags)) {

		mmap_read_unlock(mm);

		fault = 0;

		code = SEGV_ACCERR;

		goto bad_area;

	}



	fault = handle_mm_fault(vma, addr & PAGE_MASK, flags, regs);



	/* If we need to retry but a fatal signal is pending, handle the
@@ -358,12 +361,11 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) 
	mmap_read_unlock(mm);

done:



	/*

	 * Handle the "normal" case first - VM_FAULT_MAJOR

	 */

	if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP | VM_FAULT_BADACCESS))))

	/* Handle the "normal" case first */

	if (likely(!(fault & VM_FAULT_ERROR)))

		return 0;



	code = SEGV_MAPERR;

bad_area:

	/*

	 * If we are in kernel mode at this point, we
@@ -395,8 +397,6 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) 
		 * isn't in our memory map..

		 */

		sig = SIGSEGV;

		code = fault == VM_FAULT_BADACCESS ?

			SEGV_ACCERR : SEGV_MAPERR;

	}



	__do_user_fault(addr, fsr, sig, code, regs);