Commit dde16072 authored by Peter Xu's avatar Peter Xu Committed by Linus Torvalds
Browse files

mm: introduce FAULT_FLAG_DEFAULT 



Although there're tons of arch-specific page fault handlers, most of them
are still sharing the same initial value of the page fault flags.  Say,
merely all of the page fault handlers would allow the fault to be retried,
and they also allow the fault to respond to SIGKILL.

Let's define a default value for the fault flags to replace those initial
page fault flags that were copied over.  With this, it'll be far easier to
introduce new fault flag that can be used by all the architectures instead
of touching all the archs.

Signed-off-by: default avatarPeter Xu <peterx@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Tested-by: default avatarBrian Geffon <bgeffon@google.com>
Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220160238.9694-1-peterx@redhat.com


Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent ef429ee7

arch/alpha/mm/fault.c

+1 −1
Original line number Diff line number Diff line
@@ -89,7 +89,7 @@ do_page_fault(unsigned long address, unsigned long mmcsr, 
	const struct exception_table_entry *fixup;

	int si_code = SEGV_MAPERR;

	vm_fault_t fault;

	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;

	unsigned int flags = FAULT_FLAG_DEFAULT;



	/* As of EV6, a load into $31/$f31 is a prefetch, and never faults

	   (or is suppressed by the PALcode).  Support that for older CPUs

arch/arc/mm/fault.c

+1 −1
Original line number Diff line number Diff line
@@ -100,7 +100,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs) 
	         (regs->ecr_cause == ECR_C_PROTV_INST_FETCH))

		exec = 1;



	flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;

	flags = FAULT_FLAG_DEFAULT;

	if (user_mode(regs))

		flags |= FAULT_FLAG_USER;

	if (write)

arch/arm/mm/fault.c

+1 −1
Original line number Diff line number Diff line
@@ -241,7 +241,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) 
	struct mm_struct *mm;

	int sig, code;

	vm_fault_t fault;

	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;

	unsigned int flags = FAULT_FLAG_DEFAULT;



	if (kprobe_page_fault(regs, fsr))

		return 0;

arch/arm64/mm/fault.c

+1 −1
Original line number Diff line number Diff line
@@ -446,7 +446,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr, 
	struct mm_struct *mm = current->mm;

	vm_fault_t fault, major = 0;

	unsigned long vm_flags = VM_READ | VM_WRITE | VM_EXEC;

	unsigned int mm_flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;

	unsigned int mm_flags = FAULT_FLAG_DEFAULT;



	if (kprobe_page_fault(regs, esr))

		return 0;

arch/hexagon/mm/vm_fault.c

+1 −1
Original line number Diff line number Diff line
@@ -41,7 +41,7 @@ void do_page_fault(unsigned long address, long cause, struct pt_regs *regs) 
	int si_code = SEGV_MAPERR;

	vm_fault_t fault;

	const struct exception_table_entry *fixup;

	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;

	unsigned int flags = FAULT_FLAG_DEFAULT;



	/*

	 * If we're in an interrupt or have no user context,

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