Commit-ID: aa37c51b9421d66f7931c5fdcb9ce80c450974be Gitweb: https://git.kernel.org/tip/aa37c51b9421d66f7931c5fdcb9ce80c450974be Author: Dave Hansen <[email protected]> AuthorDate: Fri, 28 Sep 2018 09:02:23 -0700 Committer: Peter Zijlstra <[email protected]> CommitDate: Tue, 9 Oct 2018 16:51:15 +0200
x86/mm: Break out user address space handling The last patch broke out kernel address space handing into its own helper. Now, do the same for user address space handling. Cc: [email protected] Cc: Jann Horn <[email protected]> Cc: Sean Christopherson <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Andy Lutomirski <[email protected]> Signed-off-by: Dave Hansen <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Link: http://lkml.kernel.org/r/[email protected] --- arch/x86/mm/fault.c | 47 ++++++++++++++++++++++++++++------------------- 1 file changed, 28 insertions(+), 19 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index c7e32f453852..0d1f5d39fc63 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -966,6 +966,7 @@ bad_area_access_error(struct pt_regs *regs, unsigned long error_code, __bad_area(regs, error_code, address, vma, SEGV_ACCERR); } +/* Handle faults in the kernel portion of the address space */ static void do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address, u32 *pkey, unsigned int fault) @@ -1254,14 +1255,11 @@ do_kern_addr_fault(struct pt_regs *regs, unsigned long hw_error_code, } NOKPROBE_SYMBOL(do_kern_addr_fault); -/* - * This routine handles page faults. It determines the address, - * and the problem, and then passes it off to one of the appropriate - * routines. - */ -static noinline void -__do_page_fault(struct pt_regs *regs, unsigned long hw_error_code, - unsigned long address) +/* Handle faults in the user portion of the address space */ +static inline +void do_user_addr_fault(struct pt_regs *regs, + unsigned long hw_error_code, + unsigned long address) { unsigned long sw_error_code; struct vm_area_struct *vma; @@ -1274,17 +1272,6 @@ __do_page_fault(struct pt_regs *regs, unsigned long hw_error_code, tsk = current; mm = tsk->mm; - prefetchw(&mm->mmap_sem); - - if (unlikely(kmmio_fault(regs, address))) - return; - - /* Was the fault on kernel-controlled part of the address space? */ - if (unlikely(fault_in_kernel_space(address))) { - do_kern_addr_fault(regs, hw_error_code, address); - return; - } - /* kprobes don't want to hook the spurious faults: */ if (unlikely(kprobes_fault(regs))) return; @@ -1488,6 +1475,28 @@ good_area: check_v8086_mode(regs, address, tsk); } +NOKPROBE_SYMBOL(do_user_addr_fault); + +/* + * This routine handles page faults. It determines the address, + * and the problem, and then passes it off to one of the appropriate + * routines. + */ +static noinline void +__do_page_fault(struct pt_regs *regs, unsigned long hw_error_code, + unsigned long address) +{ + prefetchw(¤t->mm->mmap_sem); + + if (unlikely(kmmio_fault(regs, address))) + return; + + /* Was the fault on kernel-controlled part of the address space? */ + if (unlikely(fault_in_kernel_space(address))) + do_kern_addr_fault(regs, hw_error_code, address); + else + do_user_addr_fault(regs, hw_error_code, address); +} NOKPROBE_SYMBOL(__do_page_fault); static nokprobe_inline void
