riscv/mm: Convert to using lock_mm_and_find_vma()

commit 7267ef7b0b77f4ed23b7b3c87d8eca7bd9c2d007 upstream.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[6.1: Kconfig context]
Signed-off-by: Samuel Mendoza-Jonas <samjonas@amazon.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index a85bbe2..6bf8dc0 100644 (file)
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -114,6 +114,7 @@ config RISCV
        select HAVE_RSEQ
        select IRQ_DOMAIN
        select IRQ_FORCED_THREADING
+       select LOCK_MM_AND_FIND_VMA
        select MODULES_USE_ELF_RELA if MODULES
        select MODULE_SECTIONS if MODULES
        select OF

diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index eb0774d..274bc6d 100644 (file)
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -83,13 +83,13 @@ static inline void mm_fault_error(struct pt_regs *regs, unsigned long addr, vm_f
        BUG();
 }
 
-static inline void bad_area(struct pt_regs *regs, struct mm_struct *mm, int code, unsigned long addr)
+static inline void
+bad_area_nosemaphore(struct pt_regs *regs, int code, unsigned long addr)
 {
        /*
         * Something tried to access memory that isn't in our memory map.
         * Fix it, but check if it's kernel or user first.
         */
-       mmap_read_unlock(mm);
        /* User mode accesses just cause a SIGSEGV */
        if (user_mode(regs)) {
                do_trap(regs, SIGSEGV, code, addr);
@@ -99,6 +99,15 @@ static inline void bad_area(struct pt_regs *regs, struct mm_struct *mm, int code
        no_context(regs, addr);
 }
 
+static inline void
+bad_area(struct pt_regs *regs, struct mm_struct *mm, int code,
+        unsigned long addr)
+{
+       mmap_read_unlock(mm);
+
+       bad_area_nosemaphore(regs, code, addr);
+}
+
 static inline void vmalloc_fault(struct pt_regs *regs, int code, unsigned long addr)
 {
        pgd_t *pgd, *pgd_k;
@@ -281,23 +290,10 @@ asmlinkage void do_page_fault(struct pt_regs *regs)
        else if (cause == EXC_INST_PAGE_FAULT)
                flags |= FAULT_FLAG_INSTRUCTION;
 retry:
-       mmap_read_lock(mm);
-       vma = find_vma(mm, addr);
+       vma = lock_mm_and_find_vma(mm, addr, regs);
        if (unlikely(!vma)) {
                tsk->thread.bad_cause = cause;
-               bad_area(regs, mm, code, addr);
-               return;
-       }
-       if (likely(vma->vm_start <= addr))
-               goto good_area;
-       if (unlikely(!(vma->vm_flags & VM_GROWSDOWN))) {
-               tsk->thread.bad_cause = cause;
-               bad_area(regs, mm, code, addr);
-               return;
-       }
-       if (unlikely(expand_stack(vma, addr))) {
-               tsk->thread.bad_cause = cause;
-               bad_area(regs, mm, code, addr);
+               bad_area_nosemaphore(regs, code, addr);
                return;
        }
 
@@ -305,7 +301,6 @@ retry:
         * Ok, we have a good vm_area for this memory access, so
         * we can handle it.
         */
-good_area:
        code = SEGV_ACCERR;
 
        if (unlikely(access_error(cause, vma))) {